2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
4 * 2002 Thomas Vander Stichele <thomas@apestaart.org>
6 * gstutils.c: Utility functions
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
26 * @short_description: Various utility functions
30 #include "gst_private.h"
34 #include "gstghostpad.h"
40 #include "gst-i18n-lib.h"
41 #include "glib-compat-private.h"
46 * @mem: a pointer to the memory to dump
47 * @size: the size of the memory block to dump
49 * Dumps the memory block into a hex representation. Useful for debugging.
52 gst_util_dump_mem (const guchar * mem, guint size)
55 GString *string = g_string_sized_new (50);
56 GString *chars = g_string_sized_new (18);
60 if (g_ascii_isprint (mem[i]))
61 g_string_append_c (chars, mem[i]);
63 g_string_append_c (chars, '.');
65 g_string_append_printf (string, "%02x ", mem[i]);
70 if (j == 16 || i == size) {
71 g_print ("%08x (%p): %-48.48s %-16.16s\n", i - j, mem + i - j,
72 string->str, chars->str);
73 g_string_set_size (string, 0);
74 g_string_set_size (chars, 0);
78 g_string_free (string, TRUE);
79 g_string_free (chars, TRUE);
84 * gst_util_set_value_from_string:
85 * @value: (out caller-allocates): the value to set
86 * @value_str: the string to get the value from
88 * Converts the string to the type of the value and
89 * sets the value with it.
91 * Note that this function is dangerous as it does not return any indication
92 * if the conversion worked or not.
95 gst_util_set_value_from_string (GValue * value, const gchar * value_str)
99 g_return_if_fail (value != NULL);
100 g_return_if_fail (value_str != NULL);
102 GST_CAT_DEBUG (GST_CAT_PARAMS, "parsing '%s' to type %s", value_str,
103 g_type_name (G_VALUE_TYPE (value)));
105 res = gst_value_deserialize (value, value_str);
106 if (!res && G_VALUE_TYPE (value) == G_TYPE_BOOLEAN) {
107 /* backwards compat, all booleans that fail to parse are false */
108 g_value_set_boolean (value, FALSE);
111 g_return_if_fail (res);
115 * gst_util_set_object_arg:
116 * @object: the object to set the argument of
117 * @name: the name of the argument to set
118 * @value: the string value to set
120 * Converts the string value to the type of the objects argument and
121 * sets the argument with it.
123 * Note that this function silently returns if @object has no property named
124 * @name or when @value cannot be converted to the type of the property.
127 gst_util_set_object_arg (GObject * object, const gchar * name,
134 g_return_if_fail (G_IS_OBJECT (object));
135 g_return_if_fail (name != NULL);
136 g_return_if_fail (value != NULL);
138 pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (object), name);
142 value_type = pspec->value_type;
144 GST_DEBUG ("pspec->flags is %d, pspec->value_type is %s",
145 pspec->flags, g_type_name (value_type));
147 if (!(pspec->flags & G_PARAM_WRITABLE))
150 g_value_init (&v, value_type);
152 /* special case for element <-> xml (de)serialisation */
153 if (value_type == GST_TYPE_STRUCTURE && strcmp (value, "NULL") == 0) {
154 g_value_set_boxed (&v, NULL);
158 if (!gst_value_deserialize (&v, value))
163 g_object_set_property (object, pspec->name, &v);
167 /* work around error C2520: conversion from unsigned __int64 to double
168 * not implemented, use signed __int64
170 * These are implemented as functions because on some platforms a 64bit int to
171 * double conversion is not defined/implemented.
175 gst_util_guint64_to_gdouble (guint64 value)
177 if (value & G_GINT64_CONSTANT (0x8000000000000000))
178 return (gdouble) ((gint64) value) + (gdouble) 18446744073709551616.;
180 return (gdouble) ((gint64) value);
184 gst_util_gdouble_to_guint64 (gdouble value)
186 if (value < (gdouble) 9223372036854775808.) /* 1 << 63 */
187 return ((guint64) ((gint64) value));
189 value -= (gdouble) 18446744073709551616.;
190 return ((guint64) ((gint64) value));
193 #ifndef HAVE_UINT128_T
194 /* convenience struct for getting high and low uint32 parts of
201 #if G_BYTE_ORDER == G_BIG_ENDIAN
209 #if defined (__x86_64__) && defined (__GNUC__)
211 gst_util_uint64_mul_uint64 (GstUInt64 * c1, GstUInt64 * c0, guint64 arg1,
214 __asm__ __volatile__ ("mulq %3":"=a" (c0->ll), "=d" (c1->ll)
215 :"a" (arg1), "g" (arg2)
218 #else /* defined (__x86_64__) */
219 /* multiply two 64-bit unsigned ints into a 128-bit unsigned int. the high
220 * and low 64 bits of the product are placed in c1 and c0 respectively.
221 * this operation cannot overflow. */
223 gst_util_uint64_mul_uint64 (GstUInt64 * c1, GstUInt64 * c0, guint64 arg1,
233 /* do 128 bits multiply
241 * -------------------
244 * "a0" is optimized away, result is stored directly in c0. "b1" is
245 * optimized away, result is stored directly in c1.
247 c0->ll = (guint64) v.l.low * n.l.low;
248 a1.ll = (guint64) v.l.low * n.l.high;
249 b0.ll = (guint64) v.l.high * n.l.low;
251 /* add the high word of a0 to the low words of a1 and b0 using c1 as
252 * scrach space to capture the carry. the low word of the result becomes
253 * the final high word of c0 */
254 c1->ll = (guint64) c0->l.high + a1.l.low + b0.l.low;
255 c0->l.high = c1->l.low;
257 /* add the carry from the result above (found in the high word of c1) and
258 * the high words of a1 and b0 to b1, the result is c1. */
259 c1->ll = (guint64) v.l.high * n.l.high + c1->l.high + a1.l.high + b0.l.high;
261 #endif /* defined (__x86_64__) */
263 #if defined (__x86_64__) && defined (__GNUC__)
264 static inline guint64
265 gst_util_div128_64 (GstUInt64 c1, GstUInt64 c0, guint64 denom)
269 __asm__ __volatile__ ("divq %3":"=a" (res)
270 :"d" (c1.ll), "a" (c0.ll), "g" (denom)
276 /* count leading zeros */
278 gst_util_clz (guint32 val)
282 s = val | (val >> 1);
286 s = ~(s | (s >> 16));
287 s = s - ((s >> 1) & 0x55555555);
288 s = (s & 0x33333333) + ((s >> 2) & 0x33333333);
289 s = (s + (s >> 4)) & 0x0f0f0f0f;
291 s = (s + (s >> 16)) & 0x3f;
296 /* based on Hacker's Delight p152 */
297 static inline guint64
298 gst_util_div128_64 (GstUInt64 c1, GstUInt64 c0, guint64 denom)
300 GstUInt64 q1, q0, rhat;
301 GstUInt64 v, cmp1, cmp2;
306 /* count number of leading zeroes, we know they must be in the high
307 * part of denom since denom > G_MAXUINT32. */
308 s = gst_util_clz (v.l.high);
311 /* normalize divisor and dividend */
313 c1.ll = (c1.ll << s) | (c0.l.high >> (32 - s));
317 q1.ll = c1.ll / v.l.high;
318 rhat.ll = c1.ll - q1.ll * v.l.high;
320 cmp1.l.high = rhat.l.low;
321 cmp1.l.low = c0.l.high;
322 cmp2.ll = q1.ll * v.l.low;
324 while (q1.l.high || cmp2.ll > cmp1.ll) {
329 cmp1.l.high = rhat.l.low;
332 c1.l.high = c1.l.low;
333 c1.l.low = c0.l.high;
334 c1.ll -= q1.ll * v.ll;
335 q0.ll = c1.ll / v.l.high;
336 rhat.ll = c1.ll - q0.ll * v.l.high;
338 cmp1.l.high = rhat.l.low;
339 cmp1.l.low = c0.l.low;
340 cmp2.ll = q0.ll * v.l.low;
342 while (q0.l.high || cmp2.ll > cmp1.ll) {
347 cmp1.l.high = rhat.l.low;
350 q0.l.high += q1.l.low;
354 #endif /* defined (__GNUC__) */
356 /* This always gives the correct result because:
357 * a) val <= G_MAXUINT64-1
358 * b) (c0,c1) <= G_MAXUINT64 * (G_MAXUINT64-1)
360 * (c0,c1) == G_MAXUINT64 * G_MAXUINT64 and denom < G_MAXUINT64
361 * (note: num==denom case is handled by short path)
362 * This means that (c0,c1) either has enough space for val
363 * or that the overall result will overflow anyway.
366 /* add correction with carry */
367 #define CORRECT(c0,c1,val) \
369 if (G_MAXUINT64 - c0.ll < val) { \
370 if (G_UNLIKELY (c1.ll == G_MAXUINT64)) \
372 return G_MAXUINT64; \
379 gst_util_uint64_scale_uint64_unchecked (guint64 val, guint64 num,
380 guint64 denom, guint64 correct)
384 /* compute 128-bit numerator product */
385 gst_util_uint64_mul_uint64 (&c1, &c0, val, num);
387 /* perform rounding correction */
388 CORRECT (c0, c1, correct);
390 /* high word as big as or bigger than denom --> overflow */
391 if (G_UNLIKELY (c1.ll >= denom))
394 /* compute quotient, fits in 64 bits */
395 return gst_util_div128_64 (c1, c0, denom);
399 #define GST_MAXUINT128 ((__uint128_t) -1)
401 gst_util_uint64_scale_uint64_unchecked (guint64 val, guint64 num,
402 guint64 denom, guint64 correct)
406 /* Calculate val * num */
407 tmp = ((__uint128_t) val) * ((__uint128_t) num);
409 /* overflow checks */
410 if (G_UNLIKELY (GST_MAXUINT128 - correct < tmp))
413 /* perform rounding correction */
416 /* Divide by denom */
419 /* if larger than G_MAXUINT64 --> overflow */
420 if (G_UNLIKELY (tmp > G_MAXUINT64))
423 /* compute quotient, fits in 64 bits */
424 return (guint64) tmp;
429 #if !defined (__x86_64__) && !defined (HAVE_UINT128_T)
431 gst_util_uint64_mul_uint32 (GstUInt64 * c1, GstUInt64 * c0, guint64 arg1,
438 c0->ll = (guint64) a.l.low * arg2;
439 c1->ll = (guint64) a.l.high * arg2 + c0->l.high;
443 /* divide a 96-bit unsigned int by a 32-bit unsigned int when we know the
444 * quotient fits into 64 bits. the high 64 bits and low 32 bits of the
445 * numerator are expected in c1 and c0 respectively. */
446 static inline guint64
447 gst_util_div96_32 (guint64 c1, guint64 c0, guint32 denom)
449 c0 += (c1 % denom) << 32;
450 return ((c1 / denom) << 32) + (c0 / denom);
453 static inline guint64
454 gst_util_uint64_scale_uint32_unchecked (guint64 val, guint32 num,
455 guint32 denom, guint32 correct)
459 /* compute 96-bit numerator product */
460 gst_util_uint64_mul_uint32 (&c1, &c0, val, num);
462 /* condition numerator based on rounding mode */
463 CORRECT (c0, c1, correct);
465 /* high 32 bits as big as or bigger than denom --> overflow */
466 if (G_UNLIKELY (c1.l.high >= denom))
469 /* compute quotient, fits in 64 bits */
470 return gst_util_div96_32 (c1.ll, c0.ll, denom);
474 /* the guts of the gst_util_uint64_scale() variants */
476 _gst_util_uint64_scale (guint64 val, guint64 num, guint64 denom,
479 g_return_val_if_fail (denom != 0, G_MAXUINT64);
481 if (G_UNLIKELY (num == 0))
484 if (G_UNLIKELY (num == denom))
487 /* on 64bits we always use a full 128bits multiply/division */
488 #if !defined (__x86_64__) && !defined (HAVE_UINT128_T)
489 /* denom is low --> try to use 96 bit muldiv */
490 if (G_LIKELY (denom <= G_MAXUINT32)) {
491 /* num is low --> use 96 bit muldiv */
492 if (G_LIKELY (num <= G_MAXUINT32))
493 return gst_util_uint64_scale_uint32_unchecked (val, (guint32) num,
494 (guint32) denom, correct);
496 /* num is high but val is low --> swap and use 96-bit muldiv */
497 if (G_LIKELY (val <= G_MAXUINT32))
498 return gst_util_uint64_scale_uint32_unchecked (num, (guint32) val,
499 (guint32) denom, correct);
501 #endif /* !defined (__x86_64__) && !defined (HAVE_UINT128_T) */
503 /* val is high and num is high --> use 128-bit muldiv */
504 return gst_util_uint64_scale_uint64_unchecked (val, num, denom, correct);
508 * gst_util_uint64_scale:
509 * @val: the number to scale
510 * @num: the numerator of the scale ratio
511 * @denom: the denominator of the scale ratio
513 * Scale @val by the rational number @num / @denom, avoiding overflows and
514 * underflows and without loss of precision.
516 * This function can potentially be very slow if val and num are both
517 * greater than G_MAXUINT32.
519 * Returns: @val * @num / @denom. In the case of an overflow, this
520 * function returns G_MAXUINT64. If the result is not exactly
521 * representable as an integer it is truncated. See also
522 * gst_util_uint64_scale_round(), gst_util_uint64_scale_ceil(),
523 * gst_util_uint64_scale_int(), gst_util_uint64_scale_int_round(),
524 * gst_util_uint64_scale_int_ceil().
527 gst_util_uint64_scale (guint64 val, guint64 num, guint64 denom)
529 return _gst_util_uint64_scale (val, num, denom, 0);
533 * gst_util_uint64_scale_round:
534 * @val: the number to scale
535 * @num: the numerator of the scale ratio
536 * @denom: the denominator of the scale ratio
538 * Scale @val by the rational number @num / @denom, avoiding overflows and
539 * underflows and without loss of precision.
541 * This function can potentially be very slow if val and num are both
542 * greater than G_MAXUINT32.
544 * Returns: @val * @num / @denom. In the case of an overflow, this
545 * function returns G_MAXUINT64. If the result is not exactly
546 * representable as an integer, it is rounded to the nearest integer
547 * (half-way cases are rounded up). See also gst_util_uint64_scale(),
548 * gst_util_uint64_scale_ceil(), gst_util_uint64_scale_int(),
549 * gst_util_uint64_scale_int_round(), gst_util_uint64_scale_int_ceil().
552 gst_util_uint64_scale_round (guint64 val, guint64 num, guint64 denom)
554 return _gst_util_uint64_scale (val, num, denom, denom >> 1);
558 * gst_util_uint64_scale_ceil:
559 * @val: the number to scale
560 * @num: the numerator of the scale ratio
561 * @denom: the denominator of the scale ratio
563 * Scale @val by the rational number @num / @denom, avoiding overflows and
564 * underflows and without loss of precision.
566 * This function can potentially be very slow if val and num are both
567 * greater than G_MAXUINT32.
569 * Returns: @val * @num / @denom. In the case of an overflow, this
570 * function returns G_MAXUINT64. If the result is not exactly
571 * representable as an integer, it is rounded up. See also
572 * gst_util_uint64_scale(), gst_util_uint64_scale_round(),
573 * gst_util_uint64_scale_int(), gst_util_uint64_scale_int_round(),
574 * gst_util_uint64_scale_int_ceil().
577 gst_util_uint64_scale_ceil (guint64 val, guint64 num, guint64 denom)
579 return _gst_util_uint64_scale (val, num, denom, denom - 1);
582 /* the guts of the gst_util_uint64_scale_int() variants */
584 _gst_util_uint64_scale_int (guint64 val, gint num, gint denom, gint correct)
586 g_return_val_if_fail (denom > 0, G_MAXUINT64);
587 g_return_val_if_fail (num >= 0, G_MAXUINT64);
589 if (G_UNLIKELY (num == 0))
592 if (G_UNLIKELY (num == denom))
595 if (val <= G_MAXUINT32) {
596 /* simple case. num and denom are not negative so casts are OK. when
597 * not truncating, the additions to the numerator cannot overflow
598 * because val*num <= G_MAXUINT32 * G_MAXINT32 < G_MAXUINT64 -
599 * G_MAXINT32, so there's room to add another gint32. */
600 val *= (guint64) num;
601 /* add rounding correction */
604 return val / (guint64) denom;
606 #if !defined (__x86_64__) && !defined (HAVE_UINT128_T)
607 /* num and denom are not negative so casts are OK */
608 return gst_util_uint64_scale_uint32_unchecked (val, (guint32) num,
609 (guint32) denom, (guint32) correct);
611 /* always use full 128bits scale */
612 return gst_util_uint64_scale_uint64_unchecked (val, num, denom, correct);
617 * gst_util_uint64_scale_int:
618 * @val: guint64 (such as a #GstClockTime) to scale.
619 * @num: numerator of the scale factor.
620 * @denom: denominator of the scale factor.
622 * Scale @val by the rational number @num / @denom, avoiding overflows and
623 * underflows and without loss of precision. @num must be non-negative and
624 * @denom must be positive.
626 * Returns: @val * @num / @denom. In the case of an overflow, this
627 * function returns G_MAXUINT64. If the result is not exactly
628 * representable as an integer, it is truncated. See also
629 * gst_util_uint64_scale_int_round(), gst_util_uint64_scale_int_ceil(),
630 * gst_util_uint64_scale(), gst_util_uint64_scale_round(),
631 * gst_util_uint64_scale_ceil().
634 gst_util_uint64_scale_int (guint64 val, gint num, gint denom)
636 return _gst_util_uint64_scale_int (val, num, denom, 0);
640 * gst_util_uint64_scale_int_round:
641 * @val: guint64 (such as a #GstClockTime) to scale.
642 * @num: numerator of the scale factor.
643 * @denom: denominator of the scale factor.
645 * Scale @val by the rational number @num / @denom, avoiding overflows and
646 * underflows and without loss of precision. @num must be non-negative and
647 * @denom must be positive.
649 * Returns: @val * @num / @denom. In the case of an overflow, this
650 * function returns G_MAXUINT64. If the result is not exactly
651 * representable as an integer, it is rounded to the nearest integer
652 * (half-way cases are rounded up). See also gst_util_uint64_scale_int(),
653 * gst_util_uint64_scale_int_ceil(), gst_util_uint64_scale(),
654 * gst_util_uint64_scale_round(), gst_util_uint64_scale_ceil().
657 gst_util_uint64_scale_int_round (guint64 val, gint num, gint denom)
659 /* we can use a shift to divide by 2 because denom is required to be
661 return _gst_util_uint64_scale_int (val, num, denom, denom >> 1);
665 * gst_util_uint64_scale_int_ceil:
666 * @val: guint64 (such as a #GstClockTime) to scale.
667 * @num: numerator of the scale factor.
668 * @denom: denominator of the scale factor.
670 * Scale @val by the rational number @num / @denom, avoiding overflows and
671 * underflows and without loss of precision. @num must be non-negative and
672 * @denom must be positive.
674 * Returns: @val * @num / @denom. In the case of an overflow, this
675 * function returns G_MAXUINT64. If the result is not exactly
676 * representable as an integer, it is rounded up. See also
677 * gst_util_uint64_scale_int(), gst_util_uint64_scale_int_round(),
678 * gst_util_uint64_scale(), gst_util_uint64_scale_round(),
679 * gst_util_uint64_scale_ceil().
682 gst_util_uint64_scale_int_ceil (guint64 val, gint num, gint denom)
684 return _gst_util_uint64_scale_int (val, num, denom, denom - 1);
688 * gst_util_seqnum_next:
690 * Return a constantly incrementing sequence number.
692 * This function is used internally to GStreamer to be able to determine which
693 * events and messages are "the same". For example, elements may set the seqnum
694 * on a segment-done message to be the same as that of the last seek event, to
695 * indicate that event and the message correspond to the same segment.
697 * Returns: A constantly incrementing 32-bit unsigned integer, which might
698 * overflow back to 0 at some point. Use gst_util_seqnum_compare() to make sure
699 * you handle wraparound correctly.
702 gst_util_seqnum_next (void)
704 static gint counter = 0;
705 return g_atomic_int_add (&counter, 1);
709 * gst_util_seqnum_compare:
710 * @s1: A sequence number.
711 * @s2: Another sequence number.
713 * Compare two sequence numbers, handling wraparound.
715 * The current implementation just returns (gint32)(@s1 - @s2).
717 * Returns: A negative number if @s1 is before @s2, 0 if they are equal, or a
718 * positive number if @s1 is after @s2.
721 gst_util_seqnum_compare (guint32 s1, guint32 s2)
723 return (gint32) (s1 - s2);
726 /* -----------------------------------------------------
728 * The following code will be moved out of the main
729 * gstreamer library someday.
735 * gst_element_create_all_pads:
736 * @element: (transfer none): a #GstElement to create pads for
738 * Creates a pad for each pad template that is always available.
739 * This function is only useful during object initialization of
740 * subclasses of #GstElement.
743 gst_element_create_all_pads (GstElement * element)
747 /* FIXME: lock element */
750 gst_element_class_get_pad_template_list (GST_ELEMENT_CLASS
751 (G_OBJECT_GET_CLASS (element)));
754 GstPadTemplate *padtempl = (GstPadTemplate *) padlist->data;
756 if (padtempl->presence == GST_PAD_ALWAYS) {
759 pad = gst_pad_new_from_template (padtempl, padtempl->name_template);
761 gst_element_add_pad (element, pad);
763 padlist = padlist->next;
768 * gst_element_get_compatible_pad_template:
769 * @element: (transfer none): a #GstElement to get a compatible pad template for
770 * @compattempl: (transfer none): the #GstPadTemplate to find a compatible
773 * Retrieves a pad template from @element that is compatible with @compattempl.
774 * Pads from compatible templates can be linked together.
776 * Returns: (transfer none) (nullable): a compatible #GstPadTemplate,
777 * or %NULL if none was found. No unreferencing is necessary.
780 gst_element_get_compatible_pad_template (GstElement * element,
781 GstPadTemplate * compattempl)
783 GstPadTemplate *newtempl = NULL;
785 GstElementClass *class;
788 g_return_val_if_fail (element != NULL, NULL);
789 g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
790 g_return_val_if_fail (compattempl != NULL, NULL);
792 class = GST_ELEMENT_GET_CLASS (element);
794 padlist = gst_element_class_get_pad_template_list (class);
796 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
797 "Looking for a suitable pad template in %s out of %d templates...",
798 GST_ELEMENT_NAME (element), g_list_length (padlist));
801 GstPadTemplate *padtempl = (GstPadTemplate *) padlist->data;
805 * Check direction (must be opposite)
808 GST_CAT_LOG (GST_CAT_CAPS,
809 "checking pad template %s", padtempl->name_template);
810 if (padtempl->direction != compattempl->direction) {
811 GST_CAT_DEBUG (GST_CAT_CAPS,
812 "compatible direction: found %s pad template \"%s\"",
813 padtempl->direction == GST_PAD_SRC ? "src" : "sink",
814 padtempl->name_template);
816 GST_CAT_DEBUG (GST_CAT_CAPS,
817 "intersecting %" GST_PTR_FORMAT, GST_PAD_TEMPLATE_CAPS (compattempl));
818 GST_CAT_DEBUG (GST_CAT_CAPS,
819 "..and %" GST_PTR_FORMAT, GST_PAD_TEMPLATE_CAPS (padtempl));
821 compatible = gst_caps_can_intersect (GST_PAD_TEMPLATE_CAPS (compattempl),
822 GST_PAD_TEMPLATE_CAPS (padtempl));
824 GST_CAT_DEBUG (GST_CAT_CAPS, "caps are %scompatible",
825 (compatible ? "" : "not "));
833 padlist = g_list_next (padlist);
836 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
837 "Returning new pad template %p", newtempl);
839 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "No compatible pad template found");
845 * gst_element_get_pad_from_template:
846 * @element: (transfer none): a #GstElement.
847 * @templ: (transfer none): a #GstPadTemplate belonging to @element.
849 * Gets a pad from @element described by @templ. If the presence of @templ is
850 * #GST_PAD_REQUEST, requests a new pad. Can return %NULL for #GST_PAD_SOMETIMES
853 * Returns: (transfer full) (nullable): the #GstPad, or %NULL if one
854 * could not be found or created.
857 gst_element_get_pad_from_template (GstElement * element, GstPadTemplate * templ)
860 GstPadPresence presence;
862 /* If this function is ever exported, we need check the validity of `element'
863 * and `templ', and to make sure the template actually belongs to the
866 presence = GST_PAD_TEMPLATE_PRESENCE (templ);
870 case GST_PAD_SOMETIMES:
871 ret = gst_element_get_static_pad (element, templ->name_template);
872 if (!ret && presence == GST_PAD_ALWAYS)
874 ("Element %s has an ALWAYS template %s, but no pad of the same name",
875 GST_OBJECT_NAME (element), templ->name_template);
878 case GST_PAD_REQUEST:
879 ret = gst_element_request_pad (element, templ, NULL, NULL);
887 * gst_element_request_compatible_pad:
888 * @element: a #GstElement.
889 * @templ: the #GstPadTemplate to which the new pad should be able to link.
891 * Requests a pad from @element. The returned pad should be unlinked and
892 * compatible with @templ. Might return an existing pad, or request a new one.
894 * Returns: (nullable): a #GstPad, or %NULL if one could not be found
898 gst_element_request_compatible_pad (GstElement * element,
899 GstPadTemplate * templ)
901 GstPadTemplate *templ_new;
904 g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
905 g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
907 /* FIXME: should really loop through the templates, testing each for
908 * compatibility and pad availability. */
909 templ_new = gst_element_get_compatible_pad_template (element, templ);
911 pad = gst_element_get_pad_from_template (element, templ_new);
913 /* This can happen for non-request pads. No need to unref. */
914 if (pad && GST_PAD_PEER (pad))
921 * Checks if the source pad and the sink pad can be linked.
922 * Both @srcpad and @sinkpad must be unlinked and have a parent.
925 gst_pad_check_link (GstPad * srcpad, GstPad * sinkpad)
928 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
929 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
931 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
932 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
934 if (GST_PAD_PEER (srcpad) != NULL) {
935 GST_CAT_INFO (GST_CAT_PADS, "Source pad %s:%s has a peer, failed",
936 GST_DEBUG_PAD_NAME (srcpad));
939 if (GST_PAD_PEER (sinkpad) != NULL) {
940 GST_CAT_INFO (GST_CAT_PADS, "Sink pad %s:%s has a peer, failed",
941 GST_DEBUG_PAD_NAME (sinkpad));
944 if (!GST_PAD_IS_SRC (srcpad)) {
945 GST_CAT_INFO (GST_CAT_PADS, "Src pad %s:%s is not source pad, failed",
946 GST_DEBUG_PAD_NAME (srcpad));
949 if (!GST_PAD_IS_SINK (sinkpad)) {
950 GST_CAT_INFO (GST_CAT_PADS, "Sink pad %s:%s is not sink pad, failed",
951 GST_DEBUG_PAD_NAME (sinkpad));
954 if (GST_PAD_PARENT (srcpad) == NULL) {
955 GST_CAT_INFO (GST_CAT_PADS, "Src pad %s:%s has no parent, failed",
956 GST_DEBUG_PAD_NAME (srcpad));
959 if (GST_PAD_PARENT (sinkpad) == NULL) {
960 GST_CAT_INFO (GST_CAT_PADS, "Sink pad %s:%s has no parent, failed",
961 GST_DEBUG_PAD_NAME (srcpad));
969 * gst_element_get_compatible_pad:
970 * @element: (transfer none): a #GstElement in which the pad should be found.
971 * @pad: (transfer none): the #GstPad to find a compatible one for.
972 * @caps: (allow-none): the #GstCaps to use as a filter.
974 * Looks for an unlinked pad to which the given pad can link. It is not
975 * guaranteed that linking the pads will work, though it should work in most
978 * This function will first attempt to find a compatible unlinked ALWAYS pad,
979 * and if none can be found, it will request a compatible REQUEST pad by looking
980 * at the templates of @element.
982 * Returns: (transfer full) (nullable): the #GstPad to which a link
983 * can be made, or %NULL if one cannot be found. gst_object_unref()
987 gst_element_get_compatible_pad (GstElement * element, GstPad * pad,
991 GstPadTemplate *templ;
993 GstPad *foundpad = NULL;
995 GValue padptr = { 0, };
997 g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
998 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1000 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1001 "finding pad in %s compatible with %s:%s",
1002 GST_ELEMENT_NAME (element), GST_DEBUG_PAD_NAME (pad));
1004 g_return_val_if_fail (GST_PAD_PEER (pad) == NULL, NULL);
1008 /* try to get an existing unlinked pad */
1009 if (GST_PAD_IS_SRC (pad)) {
1010 pads = gst_element_iterate_sink_pads (element);
1011 } else if (GST_PAD_IS_SINK (pad)) {
1012 pads = gst_element_iterate_src_pads (element);
1014 pads = gst_element_iterate_pads (element);
1018 switch (gst_iterator_next (pads, &padptr)) {
1019 case GST_ITERATOR_OK:
1026 current = g_value_get_object (&padptr);
1028 GST_CAT_LOG (GST_CAT_ELEMENT_PADS, "examining pad %s:%s",
1029 GST_DEBUG_PAD_NAME (current));
1031 if (GST_PAD_IS_SRC (current)) {
1038 peer = gst_pad_get_peer (current);
1040 if (peer == NULL && gst_pad_check_link (srcpad, sinkpad)) {
1041 GstCaps *temp, *intersection;
1042 gboolean compatible;
1044 /* Now check if the two pads' caps are compatible */
1045 temp = gst_pad_query_caps (pad, NULL);
1047 intersection = gst_caps_intersect (temp, caps);
1048 gst_caps_unref (temp);
1050 intersection = temp;
1053 temp = gst_pad_query_caps (current, NULL);
1054 compatible = gst_caps_can_intersect (temp, intersection);
1055 gst_caps_unref (temp);
1056 gst_caps_unref (intersection);
1059 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1060 "found existing unlinked compatible pad %s:%s",
1061 GST_DEBUG_PAD_NAME (current));
1062 gst_iterator_free (pads);
1064 current = gst_object_ref (current);
1065 g_value_unset (&padptr);
1069 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "incompatible pads");
1072 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1073 "already linked or cannot be linked (peer = %p)", peer);
1075 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "unreffing pads");
1077 g_value_reset (&padptr);
1079 gst_object_unref (peer);
1082 case GST_ITERATOR_DONE:
1085 case GST_ITERATOR_RESYNC:
1086 gst_iterator_resync (pads);
1088 case GST_ITERATOR_ERROR:
1089 g_assert_not_reached ();
1093 g_value_unset (&padptr);
1094 gst_iterator_free (pads);
1096 GST_CAT_DEBUG_OBJECT (GST_CAT_ELEMENT_PADS, element,
1097 "Could not find a compatible unlinked always pad to link to %s:%s, now checking request pads",
1098 GST_DEBUG_PAD_NAME (pad));
1100 /* try to create a new one */
1101 /* requesting is a little crazy, we need a template. Let's create one */
1102 /* FIXME: why not gst_pad_get_pad_template (pad); */
1103 templcaps = gst_pad_query_caps (pad, NULL);
1104 templ = gst_pad_template_new ((gchar *) GST_PAD_NAME (pad),
1105 GST_PAD_DIRECTION (pad), GST_PAD_ALWAYS, templcaps);
1106 gst_caps_unref (templcaps);
1108 foundpad = gst_element_request_compatible_pad (element, templ);
1109 gst_object_unref (templ);
1112 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1113 "found existing request pad %s:%s", GST_DEBUG_PAD_NAME (foundpad));
1117 GST_CAT_INFO_OBJECT (GST_CAT_ELEMENT_PADS, element,
1118 "Could not find a compatible pad to link to %s:%s",
1119 GST_DEBUG_PAD_NAME (pad));
1124 * gst_element_state_get_name:
1125 * @state: a #GstState to get the name of.
1127 * Gets a string representing the given state.
1129 * Returns: (transfer none): a string with the name of the state.
1132 gst_element_state_get_name (GstState state)
1135 case GST_STATE_VOID_PENDING:
1136 return "VOID_PENDING";
1137 case GST_STATE_NULL:
1139 case GST_STATE_READY:
1141 case GST_STATE_PLAYING:
1143 case GST_STATE_PAUSED:
1146 /* This is a memory leak */
1147 return g_strdup_printf ("UNKNOWN!(%d)", state);
1152 * gst_element_state_change_return_get_name:
1153 * @state_ret: a #GstStateChangeReturn to get the name of.
1155 * Gets a string representing the given state change result.
1157 * Returns: (transfer none): a string with the name of the state
1161 gst_element_state_change_return_get_name (GstStateChangeReturn state_ret)
1163 switch (state_ret) {
1164 case GST_STATE_CHANGE_FAILURE:
1166 case GST_STATE_CHANGE_SUCCESS:
1168 case GST_STATE_CHANGE_ASYNC:
1170 case GST_STATE_CHANGE_NO_PREROLL:
1171 return "NO PREROLL";
1173 /* This is a memory leak */
1174 return g_strdup_printf ("UNKNOWN!(%d)", state_ret);
1180 gst_element_factory_can_accept_all_caps_in_direction (GstElementFactory *
1181 factory, const GstCaps * caps, GstPadDirection direction)
1185 g_return_val_if_fail (factory != NULL, FALSE);
1186 g_return_val_if_fail (caps != NULL, FALSE);
1188 templates = factory->staticpadtemplates;
1191 GstStaticPadTemplate *template = (GstStaticPadTemplate *) templates->data;
1193 if (template->direction == direction) {
1194 GstCaps *templcaps = gst_static_caps_get (&template->static_caps);
1196 if (gst_caps_is_always_compatible (caps, templcaps)) {
1197 gst_caps_unref (templcaps);
1200 gst_caps_unref (templcaps);
1202 templates = g_list_next (templates);
1209 gst_element_factory_can_accept_any_caps_in_direction (GstElementFactory *
1210 factory, const GstCaps * caps, GstPadDirection direction)
1214 g_return_val_if_fail (factory != NULL, FALSE);
1215 g_return_val_if_fail (caps != NULL, FALSE);
1217 templates = factory->staticpadtemplates;
1220 GstStaticPadTemplate *template = (GstStaticPadTemplate *) templates->data;
1222 if (template->direction == direction) {
1223 GstCaps *templcaps = gst_static_caps_get (&template->static_caps);
1225 if (gst_caps_can_intersect (caps, templcaps)) {
1226 gst_caps_unref (templcaps);
1229 gst_caps_unref (templcaps);
1231 templates = g_list_next (templates);
1238 * gst_element_factory_can_sink_all_caps:
1239 * @factory: factory to query
1240 * @caps: the caps to check
1242 * Checks if the factory can sink all possible capabilities.
1244 * Returns: %TRUE if the caps are fully compatible.
1247 gst_element_factory_can_sink_all_caps (GstElementFactory * factory,
1248 const GstCaps * caps)
1250 return gst_element_factory_can_accept_all_caps_in_direction (factory, caps,
1255 * gst_element_factory_can_src_all_caps:
1256 * @factory: factory to query
1257 * @caps: the caps to check
1259 * Checks if the factory can src all possible capabilities.
1261 * Returns: %TRUE if the caps are fully compatible.
1264 gst_element_factory_can_src_all_caps (GstElementFactory * factory,
1265 const GstCaps * caps)
1267 return gst_element_factory_can_accept_all_caps_in_direction (factory, caps,
1272 * gst_element_factory_can_sink_any_caps:
1273 * @factory: factory to query
1274 * @caps: the caps to check
1276 * Checks if the factory can sink any possible capability.
1278 * Returns: %TRUE if the caps have a common subset.
1281 gst_element_factory_can_sink_any_caps (GstElementFactory * factory,
1282 const GstCaps * caps)
1284 return gst_element_factory_can_accept_any_caps_in_direction (factory, caps,
1289 * gst_element_factory_can_src_any_caps:
1290 * @factory: factory to query
1291 * @caps: the caps to check
1293 * Checks if the factory can src any possible capability.
1295 * Returns: %TRUE if the caps have a common subset.
1298 gst_element_factory_can_src_any_caps (GstElementFactory * factory,
1299 const GstCaps * caps)
1301 return gst_element_factory_can_accept_any_caps_in_direction (factory, caps,
1305 /* if return val is true, *direct_child is a caller-owned ref on the direct
1306 * child of ancestor that is part of object's ancestry */
1308 object_has_ancestor (GstObject * object, GstObject * ancestor,
1309 GstObject ** direct_child)
1311 GstObject *child, *parent;
1314 *direct_child = NULL;
1316 child = gst_object_ref (object);
1317 parent = gst_object_get_parent (object);
1320 if (ancestor == parent) {
1322 *direct_child = child;
1324 gst_object_unref (child);
1325 gst_object_unref (parent);
1329 gst_object_unref (child);
1331 parent = gst_object_get_parent (parent);
1334 gst_object_unref (child);
1339 /* caller owns return */
1341 find_common_root (GstObject * o1, GstObject * o2)
1343 GstObject *top = o1;
1344 GstObject *kid1, *kid2;
1345 GstObject *root = NULL;
1347 while (GST_OBJECT_PARENT (top))
1348 top = GST_OBJECT_PARENT (top);
1350 /* the itsy-bitsy spider... */
1352 if (!object_has_ancestor (o2, top, &kid2))
1355 root = gst_object_ref (top);
1357 if (!object_has_ancestor (o1, kid2, &kid1)) {
1358 gst_object_unref (kid2);
1362 if (!object_has_ancestor (o2, kid1, &kid2)) {
1363 gst_object_unref (kid1);
1370 /* caller does not own return */
1372 ghost_up (GstElement * e, GstPad * pad)
1374 static gint ghost_pad_index = 0;
1379 GstObject *parent = GST_OBJECT_PARENT (e);
1381 name = g_strdup_printf ("ghost%d", ghost_pad_index++);
1382 gpad = gst_ghost_pad_new (name, pad);
1386 gst_element_get_state (e, ¤t, &next, 0);
1388 if (current > GST_STATE_READY || next == GST_STATE_PAUSED)
1389 gst_pad_set_active (gpad, TRUE);
1391 if (!gst_element_add_pad ((GstElement *) parent, gpad)) {
1392 g_warning ("Pad named %s already exists in element %s\n",
1393 GST_OBJECT_NAME (gpad), GST_OBJECT_NAME (parent));
1394 gst_object_unref ((GstObject *) gpad);
1395 GST_STATE_UNLOCK (e);
1398 GST_STATE_UNLOCK (e);
1404 remove_pad (gpointer ppad, gpointer unused)
1408 if (!gst_element_remove_pad ((GstElement *) GST_OBJECT_PARENT (pad), pad))
1409 g_warning ("Couldn't remove pad %s from element %s",
1410 GST_OBJECT_NAME (pad), GST_OBJECT_NAME (GST_OBJECT_PARENT (pad)));
1414 prepare_link_maybe_ghosting (GstPad ** src, GstPad ** sink,
1415 GSList ** pads_created)
1419 GSList *pads_created_local = NULL;
1421 g_assert (pads_created);
1423 e1 = GST_OBJECT_PARENT (*src);
1424 e2 = GST_OBJECT_PARENT (*sink);
1426 if (G_UNLIKELY (e1 == NULL)) {
1427 GST_WARNING ("Trying to ghost a pad that doesn't have a parent: %"
1428 GST_PTR_FORMAT, *src);
1431 if (G_UNLIKELY (e2 == NULL)) {
1432 GST_WARNING ("Trying to ghost a pad that doesn't have a parent: %"
1433 GST_PTR_FORMAT, *sink);
1437 if (GST_OBJECT_PARENT (e1) == GST_OBJECT_PARENT (e2)) {
1438 GST_CAT_INFO (GST_CAT_PADS, "%s and %s in same bin, no need for ghost pads",
1439 GST_OBJECT_NAME (e1), GST_OBJECT_NAME (e2));
1443 GST_CAT_INFO (GST_CAT_PADS, "%s and %s not in same bin, making ghost pads",
1444 GST_OBJECT_NAME (e1), GST_OBJECT_NAME (e2));
1446 /* we need to setup some ghost pads */
1447 root = find_common_root (e1, e2);
1449 if (GST_OBJECT_PARENT (e1) == NULL)
1450 g_warning ("Trying to link elements %s and %s that don't share a common "
1451 "ancestor: %s hasn't been added to a bin or pipeline, but %s is in %s",
1452 GST_ELEMENT_NAME (e1), GST_ELEMENT_NAME (e2),
1453 GST_ELEMENT_NAME (e1), GST_ELEMENT_NAME (e2),
1454 GST_ELEMENT_NAME (GST_OBJECT_PARENT (e2)));
1455 else if (GST_OBJECT_PARENT (e2) == NULL)
1456 g_warning ("Trying to link elements %s and %s that don't share a common "
1457 "ancestor: %s hasn't been added to a bin or pipeline, and %s is in %s",
1458 GST_ELEMENT_NAME (e1), GST_ELEMENT_NAME (e2),
1459 GST_ELEMENT_NAME (e2), GST_ELEMENT_NAME (e1),
1460 GST_ELEMENT_NAME (GST_OBJECT_PARENT (e1)));
1462 g_warning ("Trying to link elements %s and %s that don't share a common "
1463 "ancestor: %s is in %s, and %s is in %s",
1464 GST_ELEMENT_NAME (e1), GST_ELEMENT_NAME (e2),
1465 GST_ELEMENT_NAME (e1), GST_ELEMENT_NAME (GST_OBJECT_PARENT (e1)),
1466 GST_ELEMENT_NAME (e2), GST_ELEMENT_NAME (GST_OBJECT_PARENT (e2)));
1470 while (GST_OBJECT_PARENT (e1) != root) {
1471 *src = ghost_up ((GstElement *) e1, *src);
1474 e1 = GST_OBJECT_PARENT (*src);
1475 pads_created_local = g_slist_prepend (pads_created_local, *src);
1477 while (GST_OBJECT_PARENT (e2) != root) {
1478 *sink = ghost_up ((GstElement *) e2, *sink);
1481 e2 = GST_OBJECT_PARENT (*sink);
1482 pads_created_local = g_slist_prepend (pads_created_local, *sink);
1485 gst_object_unref (root);
1486 *pads_created = g_slist_concat (*pads_created, pads_created_local);
1490 gst_object_unref (root);
1491 g_slist_foreach (pads_created_local, remove_pad, NULL);
1492 g_slist_free (pads_created_local);
1497 pad_link_maybe_ghosting (GstPad * src, GstPad * sink, GstPadLinkCheck flags)
1499 GSList *pads_created = NULL;
1502 if (!prepare_link_maybe_ghosting (&src, &sink, &pads_created)) {
1505 ret = (gst_pad_link_full (src, sink, flags) == GST_PAD_LINK_OK);
1509 g_slist_foreach (pads_created, remove_pad, NULL);
1511 g_slist_free (pads_created);
1517 release_and_unref_pad (GstElement * element, GstPad * pad, gboolean requestpad)
1521 gst_element_release_request_pad (element, pad);
1522 gst_object_unref (pad);
1527 * gst_element_link_pads_full:
1528 * @src: a #GstElement containing the source pad.
1529 * @srcpadname: (allow-none): the name of the #GstPad in source element
1530 * or %NULL for any pad.
1531 * @dest: (transfer none): the #GstElement containing the destination pad.
1532 * @destpadname: (allow-none): the name of the #GstPad in destination element,
1533 * or %NULL for any pad.
1534 * @flags: the #GstPadLinkCheck to be performed when linking pads.
1536 * Links the two named pads of the source and destination elements.
1537 * Side effect is that if one of the pads has no parent, it becomes a
1538 * child of the parent of the other element. If they have different
1539 * parents, the link fails.
1541 * Calling gst_element_link_pads_full() with @flags == %GST_PAD_LINK_CHECK_DEFAULT
1542 * is the same as calling gst_element_link_pads() and the recommended way of
1543 * linking pads with safety checks applied.
1545 * This is a convenience function for gst_pad_link_full().
1547 * Returns: %TRUE if the pads could be linked, %FALSE otherwise.
1550 gst_element_link_pads_full (GstElement * src, const gchar * srcpadname,
1551 GstElement * dest, const gchar * destpadname, GstPadLinkCheck flags)
1553 const GList *srcpads, *destpads, *srctempls, *desttempls, *l;
1554 GstPad *srcpad, *destpad;
1555 GstPadTemplate *srctempl, *desttempl;
1556 GstElementClass *srcclass, *destclass;
1557 gboolean srcrequest, destrequest;
1560 g_return_val_if_fail (GST_IS_ELEMENT (src), FALSE);
1561 g_return_val_if_fail (GST_IS_ELEMENT (dest), FALSE);
1563 GST_CAT_INFO (GST_CAT_ELEMENT_PADS,
1564 "trying to link element %s:%s to element %s:%s", GST_ELEMENT_NAME (src),
1565 srcpadname ? srcpadname : "(any)", GST_ELEMENT_NAME (dest),
1566 destpadname ? destpadname : "(any)");
1569 destrequest = FALSE;
1573 /* name specified, look it up */
1574 if (!(srcpad = gst_element_get_static_pad (src, srcpadname))) {
1575 if ((srcpad = gst_element_get_request_pad (src, srcpadname)))
1579 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no pad %s:%s",
1580 GST_ELEMENT_NAME (src), srcpadname);
1583 if (!(GST_PAD_DIRECTION (srcpad) == GST_PAD_SRC)) {
1584 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is no src pad",
1585 GST_DEBUG_PAD_NAME (srcpad));
1586 release_and_unref_pad (src, srcpad, srcrequest);
1589 if (GST_PAD_PEER (srcpad) != NULL) {
1590 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1591 "pad %s:%s is already linked to %s:%s", GST_DEBUG_PAD_NAME (srcpad),
1592 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
1593 /* already linked request pads look like static pads, so the request pad
1594 * was never requested a second time above, so no need to release it */
1595 gst_object_unref (srcpad);
1601 /* no name given, get the first available pad */
1602 GST_OBJECT_LOCK (src);
1603 srcpads = GST_ELEMENT_PADS (src);
1604 srcpad = srcpads ? GST_PAD_CAST (srcpads->data) : NULL;
1606 gst_object_ref (srcpad);
1607 GST_OBJECT_UNLOCK (src);
1610 /* get a destination pad */
1612 /* name specified, look it up */
1613 if (!(destpad = gst_element_get_static_pad (dest, destpadname))) {
1614 if ((destpad = gst_element_get_request_pad (dest, destpadname)))
1618 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no pad %s:%s",
1619 GST_ELEMENT_NAME (dest), destpadname);
1620 release_and_unref_pad (src, srcpad, srcrequest);
1623 if (!(GST_PAD_DIRECTION (destpad) == GST_PAD_SINK)) {
1624 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is no sink pad",
1625 GST_DEBUG_PAD_NAME (destpad));
1626 release_and_unref_pad (src, srcpad, srcrequest);
1627 release_and_unref_pad (dest, destpad, destrequest);
1630 if (GST_PAD_PEER (destpad) != NULL) {
1631 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1632 "pad %s:%s is already linked to %s:%s",
1633 GST_DEBUG_PAD_NAME (destpad),
1634 GST_DEBUG_PAD_NAME (GST_PAD_PEER (destpad)));
1635 release_and_unref_pad (src, srcpad, srcrequest);
1636 /* already linked request pads look like static pads, so the request pad
1637 * was never requested a second time above, so no need to release it */
1638 gst_object_unref (destpad);
1644 /* no name given, get the first available pad */
1645 GST_OBJECT_LOCK (dest);
1646 destpads = GST_ELEMENT_PADS (dest);
1647 destpad = destpads ? GST_PAD_CAST (destpads->data) : NULL;
1649 gst_object_ref (destpad);
1650 GST_OBJECT_UNLOCK (dest);
1653 if (srcpadname && destpadname) {
1656 /* two explicitly specified pads */
1657 result = pad_link_maybe_ghosting (srcpad, destpad, flags);
1660 gst_object_unref (srcpad);
1661 gst_object_unref (destpad);
1663 release_and_unref_pad (src, srcpad, srcrequest);
1664 release_and_unref_pad (dest, destpad, destrequest);
1670 /* loop through the allowed pads in the source, trying to find a
1671 * compatible destination pad */
1672 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1673 "looping through allowed src and dest pads");
1675 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "trying src pad %s:%s",
1676 GST_DEBUG_PAD_NAME (srcpad));
1677 if ((GST_PAD_DIRECTION (srcpad) == GST_PAD_SRC) &&
1678 (GST_PAD_PEER (srcpad) == NULL)) {
1679 gboolean temprequest = FALSE;
1684 gst_object_ref (temp);
1686 temp = gst_element_get_compatible_pad (dest, srcpad, NULL);
1687 if (temp && GST_PAD_PAD_TEMPLATE (temp)
1688 && GST_PAD_TEMPLATE_PRESENCE (GST_PAD_PAD_TEMPLATE (temp)) ==
1694 if (temp && pad_link_maybe_ghosting (srcpad, temp, flags)) {
1695 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "linked pad %s:%s to pad %s:%s",
1696 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (temp));
1698 gst_object_unref (destpad);
1699 gst_object_unref (srcpad);
1700 gst_object_unref (temp);
1706 gst_element_release_request_pad (dest, temp);
1707 gst_object_unref (temp);
1710 /* find a better way for this mess */
1712 srcpads = g_list_next (srcpads);
1714 gst_object_unref (srcpad);
1715 srcpad = GST_PAD_CAST (srcpads->data);
1716 gst_object_ref (srcpad);
1722 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s:%s to %s",
1723 GST_DEBUG_PAD_NAME (srcpad), GST_ELEMENT_NAME (dest));
1724 /* no need to release any request pad as both src- and destpadname must be
1725 * set to end up here, but this case has already been taken care of above */
1727 gst_object_unref (destpad);
1731 release_and_unref_pad (src, srcpad, srcrequest);
1736 /* loop through the existing pads in the destination */
1738 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "trying dest pad %s:%s",
1739 GST_DEBUG_PAD_NAME (destpad));
1740 if ((GST_PAD_DIRECTION (destpad) == GST_PAD_SINK) &&
1741 (GST_PAD_PEER (destpad) == NULL)) {
1742 GstPad *temp = gst_element_get_compatible_pad (src, destpad, NULL);
1743 gboolean temprequest = FALSE;
1745 if (temp && GST_PAD_PAD_TEMPLATE (temp)
1746 && GST_PAD_TEMPLATE_PRESENCE (GST_PAD_PAD_TEMPLATE (temp)) ==
1751 if (temp && pad_link_maybe_ghosting (temp, destpad, flags)) {
1752 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "linked pad %s:%s to pad %s:%s",
1753 GST_DEBUG_PAD_NAME (temp), GST_DEBUG_PAD_NAME (destpad));
1754 gst_object_unref (temp);
1755 gst_object_unref (destpad);
1759 release_and_unref_pad (src, temp, temprequest);
1762 destpads = g_list_next (destpads);
1764 gst_object_unref (destpad);
1765 destpad = GST_PAD_CAST (destpads->data);
1766 gst_object_ref (destpad);
1773 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s to %s:%s",
1774 GST_ELEMENT_NAME (src), GST_DEBUG_PAD_NAME (destpad));
1775 release_and_unref_pad (dest, destpad, destrequest);
1778 /* no need to release any request pad as the case of unset destpatname and
1779 * destpad being a requst pad has already been taken care of when looking
1780 * though the destination pads above */
1782 gst_object_unref (destpad);
1787 srcclass = GST_ELEMENT_GET_CLASS (src);
1788 destclass = GST_ELEMENT_GET_CLASS (dest);
1790 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1791 "we might have request pads on both sides, checking...");
1792 srctempls = gst_element_class_get_pad_template_list (srcclass);
1793 desttempls = gst_element_class_get_pad_template_list (destclass);
1795 if (srctempls && desttempls) {
1797 srctempl = (GstPadTemplate *) srctempls->data;
1798 if (srctempl->presence == GST_PAD_REQUEST) {
1799 for (l = desttempls; l; l = l->next) {
1800 desttempl = (GstPadTemplate *) l->data;
1801 if (desttempl->presence == GST_PAD_REQUEST &&
1802 desttempl->direction != srctempl->direction) {
1803 GstCaps *srccaps, *destcaps;
1805 srccaps = gst_pad_template_get_caps (srctempl);
1806 destcaps = gst_pad_template_get_caps (desttempl);
1807 if (gst_caps_is_always_compatible (srccaps, destcaps)) {
1809 gst_element_request_pad (src, srctempl,
1810 srctempl->name_template, NULL);
1812 gst_element_request_pad (dest, desttempl,
1813 desttempl->name_template, NULL);
1814 if (srcpad && destpad
1815 && pad_link_maybe_ghosting (srcpad, destpad, flags)) {
1816 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1817 "linked pad %s:%s to pad %s:%s",
1818 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (destpad));
1819 gst_object_unref (srcpad);
1820 gst_object_unref (destpad);
1821 gst_caps_unref (srccaps);
1822 gst_caps_unref (destcaps);
1825 /* it failed, so we release the request pads */
1827 gst_element_release_request_pad (src, srcpad);
1828 gst_object_unref (srcpad);
1831 gst_element_release_request_pad (dest, destpad);
1832 gst_object_unref (destpad);
1835 gst_caps_unref (srccaps);
1836 gst_caps_unref (destcaps);
1840 srctempls = srctempls->next;
1844 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s to %s",
1845 GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (dest));
1850 * gst_element_link_pads:
1851 * @src: a #GstElement containing the source pad.
1852 * @srcpadname: (allow-none): the name of the #GstPad in source element
1853 * or %NULL for any pad.
1854 * @dest: (transfer none): the #GstElement containing the destination pad.
1855 * @destpadname: (allow-none): the name of the #GstPad in destination element,
1856 * or %NULL for any pad.
1858 * Links the two named pads of the source and destination elements.
1859 * Side effect is that if one of the pads has no parent, it becomes a
1860 * child of the parent of the other element. If they have different
1861 * parents, the link fails.
1863 * Returns: %TRUE if the pads could be linked, %FALSE otherwise.
1866 gst_element_link_pads (GstElement * src, const gchar * srcpadname,
1867 GstElement * dest, const gchar * destpadname)
1869 return gst_element_link_pads_full (src, srcpadname, dest, destpadname,
1870 GST_PAD_LINK_CHECK_DEFAULT);
1874 * gst_element_link_pads_filtered:
1875 * @src: a #GstElement containing the source pad.
1876 * @srcpadname: (allow-none): the name of the #GstPad in source element
1877 * or %NULL for any pad.
1878 * @dest: (transfer none): the #GstElement containing the destination pad.
1879 * @destpadname: (allow-none): the name of the #GstPad in destination element
1880 * or %NULL for any pad.
1881 * @filter: (transfer none) (allow-none): the #GstCaps to filter the link,
1882 * or %NULL for no filter.
1884 * Links the two named pads of the source and destination elements. Side effect
1885 * is that if one of the pads has no parent, it becomes a child of the parent of
1886 * the other element. If they have different parents, the link fails. If @caps
1887 * is not %NULL, makes sure that the caps of the link is a subset of @caps.
1889 * Returns: %TRUE if the pads could be linked, %FALSE otherwise.
1892 gst_element_link_pads_filtered (GstElement * src, const gchar * srcpadname,
1893 GstElement * dest, const gchar * destpadname, GstCaps * filter)
1896 g_return_val_if_fail (GST_IS_ELEMENT (src), FALSE);
1897 g_return_val_if_fail (GST_IS_ELEMENT (dest), FALSE);
1898 g_return_val_if_fail (filter == NULL || GST_IS_CAPS (filter), FALSE);
1901 GstElement *capsfilter;
1903 GstState state, pending;
1906 capsfilter = gst_element_factory_make ("capsfilter", NULL);
1908 GST_ERROR ("Could not make a capsfilter");
1912 parent = gst_object_get_parent (GST_OBJECT (src));
1913 g_return_val_if_fail (GST_IS_BIN (parent), FALSE);
1915 gst_element_get_state (GST_ELEMENT_CAST (parent), &state, &pending, 0);
1917 if (!gst_bin_add (GST_BIN (parent), capsfilter)) {
1918 GST_ERROR ("Could not add capsfilter");
1919 gst_object_unref (capsfilter);
1920 gst_object_unref (parent);
1924 if (pending != GST_STATE_VOID_PENDING)
1927 gst_element_set_state (capsfilter, state);
1929 gst_object_unref (parent);
1931 g_object_set (capsfilter, "caps", filter, NULL);
1933 lr1 = gst_element_link_pads (src, srcpadname, capsfilter, "sink");
1934 lr2 = gst_element_link_pads (capsfilter, "src", dest, destpadname);
1939 GST_INFO ("Could not link pads: %s:%s - capsfilter:sink",
1940 GST_ELEMENT_NAME (src), srcpadname);
1942 GST_INFO ("Could not link pads: capsfilter:src - %s:%s",
1943 GST_ELEMENT_NAME (dest), destpadname);
1945 gst_element_set_state (capsfilter, GST_STATE_NULL);
1946 /* this will unlink and unref as appropriate */
1947 gst_bin_remove (GST_BIN (GST_OBJECT_PARENT (capsfilter)), capsfilter);
1951 if (gst_element_link_pads (src, srcpadname, dest, destpadname)) {
1954 GST_INFO ("Could not link pads: %s:%s - %s:%s", GST_ELEMENT_NAME (src),
1955 srcpadname, GST_ELEMENT_NAME (dest), destpadname);
1963 * @src: (transfer none): a #GstElement containing the source pad.
1964 * @dest: (transfer none): the #GstElement containing the destination pad.
1966 * Links @src to @dest. The link must be from source to
1967 * destination; the other direction will not be tried. The function looks for
1968 * existing pads that aren't linked yet. It will request new pads if necessary.
1969 * Such pads need to be released manually when unlinking.
1970 * If multiple links are possible, only one is established.
1972 * Make sure you have added your elements to a bin or pipeline with
1973 * gst_bin_add() before trying to link them.
1975 * Returns: %TRUE if the elements could be linked, %FALSE otherwise.
1978 gst_element_link (GstElement * src, GstElement * dest)
1980 return gst_element_link_pads (src, NULL, dest, NULL);
1984 * gst_element_link_many:
1985 * @element_1: (transfer none): the first #GstElement in the link chain.
1986 * @element_2: (transfer none): the second #GstElement in the link chain.
1987 * @...: the %NULL-terminated list of elements to link in order.
1989 * Chain together a series of elements. Uses gst_element_link().
1990 * Make sure you have added your elements to a bin or pipeline with
1991 * gst_bin_add() before trying to link them.
1993 * Returns: %TRUE on success, %FALSE otherwise.
1996 gst_element_link_many (GstElement * element_1, GstElement * element_2, ...)
1998 gboolean res = TRUE;
2001 g_return_val_if_fail (GST_IS_ELEMENT (element_1), FALSE);
2002 g_return_val_if_fail (GST_IS_ELEMENT (element_2), FALSE);
2004 va_start (args, element_2);
2007 if (!gst_element_link (element_1, element_2)) {
2012 element_1 = element_2;
2013 element_2 = va_arg (args, GstElement *);
2022 * gst_element_link_filtered:
2023 * @src: a #GstElement containing the source pad.
2024 * @dest: (transfer none): the #GstElement containing the destination pad.
2025 * @filter: (transfer none) (allow-none): the #GstCaps to filter the link,
2026 * or %NULL for no filter.
2028 * Links @src to @dest using the given caps as filtercaps.
2029 * The link must be from source to
2030 * destination; the other direction will not be tried. The function looks for
2031 * existing pads that aren't linked yet. It will request new pads if necessary.
2032 * If multiple links are possible, only one is established.
2034 * Make sure you have added your elements to a bin or pipeline with
2035 * gst_bin_add() before trying to link them.
2037 * Returns: %TRUE if the pads could be linked, %FALSE otherwise.
2040 gst_element_link_filtered (GstElement * src, GstElement * dest,
2043 return gst_element_link_pads_filtered (src, NULL, dest, NULL, filter);
2047 * gst_element_unlink_pads:
2048 * @src: a (transfer none): #GstElement containing the source pad.
2049 * @srcpadname: the name of the #GstPad in source element.
2050 * @dest: (transfer none): a #GstElement containing the destination pad.
2051 * @destpadname: the name of the #GstPad in destination element.
2053 * Unlinks the two named pads of the source and destination elements.
2055 * This is a convenience function for gst_pad_unlink().
2058 gst_element_unlink_pads (GstElement * src, const gchar * srcpadname,
2059 GstElement * dest, const gchar * destpadname)
2061 GstPad *srcpad, *destpad;
2062 gboolean srcrequest, destrequest;
2064 srcrequest = destrequest = FALSE;
2066 g_return_if_fail (src != NULL);
2067 g_return_if_fail (GST_IS_ELEMENT (src));
2068 g_return_if_fail (srcpadname != NULL);
2069 g_return_if_fail (dest != NULL);
2070 g_return_if_fail (GST_IS_ELEMENT (dest));
2071 g_return_if_fail (destpadname != NULL);
2073 /* obtain the pads requested */
2074 if (!(srcpad = gst_element_get_static_pad (src, srcpadname)))
2075 if ((srcpad = gst_element_get_request_pad (src, srcpadname)))
2077 if (srcpad == NULL) {
2078 GST_WARNING_OBJECT (src, "source element has no pad \"%s\"", srcpadname);
2081 if (!(destpad = gst_element_get_static_pad (dest, destpadname)))
2082 if ((destpad = gst_element_get_request_pad (dest, destpadname)))
2084 if (destpad == NULL) {
2085 GST_WARNING_OBJECT (dest, "destination element has no pad \"%s\"",
2090 /* we're satisfied they can be unlinked, let's do it */
2091 gst_pad_unlink (srcpad, destpad);
2094 gst_element_release_request_pad (dest, destpad);
2095 gst_object_unref (destpad);
2099 gst_element_release_request_pad (src, srcpad);
2100 gst_object_unref (srcpad);
2104 * gst_element_unlink_many:
2105 * @element_1: (transfer none): the first #GstElement in the link chain.
2106 * @element_2: (transfer none): the second #GstElement in the link chain.
2107 * @...: the %NULL-terminated list of elements to unlink in order.
2109 * Unlinks a series of elements. Uses gst_element_unlink().
2112 gst_element_unlink_many (GstElement * element_1, GstElement * element_2, ...)
2116 g_return_if_fail (element_1 != NULL && element_2 != NULL);
2117 g_return_if_fail (GST_IS_ELEMENT (element_1) && GST_IS_ELEMENT (element_2));
2119 va_start (args, element_2);
2122 gst_element_unlink (element_1, element_2);
2124 element_1 = element_2;
2125 element_2 = va_arg (args, GstElement *);
2132 * gst_element_unlink:
2133 * @src: (transfer none): the source #GstElement to unlink.
2134 * @dest: (transfer none): the sink #GstElement to unlink.
2136 * Unlinks all source pads of the source element with all sink pads
2137 * of the sink element to which they are linked.
2139 * If the link has been made using gst_element_link(), it could have created an
2140 * requestpad, which has to be released using gst_element_release_request_pad().
2143 gst_element_unlink (GstElement * src, GstElement * dest)
2146 gboolean done = FALSE;
2147 GValue data = { 0, };
2149 g_return_if_fail (GST_IS_ELEMENT (src));
2150 g_return_if_fail (GST_IS_ELEMENT (dest));
2152 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "unlinking \"%s\" and \"%s\"",
2153 GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (dest));
2155 pads = gst_element_iterate_pads (src);
2157 switch (gst_iterator_next (pads, &data)) {
2158 case GST_ITERATOR_OK:
2160 GstPad *pad = g_value_get_object (&data);
2162 if (GST_PAD_IS_SRC (pad)) {
2163 GstPad *peerpad = gst_pad_get_peer (pad);
2165 /* see if the pad is linked and is really a pad of dest */
2167 GstElement *peerelem;
2169 peerelem = gst_pad_get_parent_element (peerpad);
2171 if (peerelem == dest) {
2172 gst_pad_unlink (pad, peerpad);
2175 gst_object_unref (peerelem);
2177 gst_object_unref (peerpad);
2180 g_value_reset (&data);
2183 case GST_ITERATOR_RESYNC:
2184 gst_iterator_resync (pads);
2186 case GST_ITERATOR_DONE:
2190 g_assert_not_reached ();
2194 g_value_unset (&data);
2195 gst_iterator_free (pads);
2199 * gst_element_query_position:
2200 * @element: a #GstElement to invoke the position query on.
2201 * @format: the #GstFormat requested
2202 * @cur: (out) (allow-none): a location in which to store the current
2203 * position, or %NULL.
2205 * Queries an element (usually top-level pipeline or playbin element) for the
2206 * stream position in nanoseconds. This will be a value between 0 and the
2207 * stream duration (if the stream duration is known). This query will usually
2208 * only work once the pipeline is prerolled (i.e. reached PAUSED or PLAYING
2209 * state). The application will receive an ASYNC_DONE message on the pipeline
2210 * bus when that is the case.
2212 * If one repeatedly calls this function one can also create a query and reuse
2213 * it in gst_element_query().
2215 * Returns: %TRUE if the query could be performed.
2218 gst_element_query_position (GstElement * element, GstFormat format,
2224 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
2225 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2227 query = gst_query_new_position (format);
2228 ret = gst_element_query (element, query);
2231 gst_query_parse_position (query, NULL, cur);
2233 gst_query_unref (query);
2239 * gst_element_query_duration:
2240 * @element: a #GstElement to invoke the duration query on.
2241 * @format: the #GstFormat requested
2242 * @duration: (out) (allow-none): A location in which to store the total duration, or %NULL.
2244 * Queries an element (usually top-level pipeline or playbin element) for the
2245 * total stream duration in nanoseconds. This query will only work once the
2246 * pipeline is prerolled (i.e. reached PAUSED or PLAYING state). The application
2247 * will receive an ASYNC_DONE message on the pipeline bus when that is the case.
2249 * If the duration changes for some reason, you will get a DURATION_CHANGED
2250 * message on the pipeline bus, in which case you should re-query the duration
2251 * using this function.
2253 * Returns: %TRUE if the query could be performed.
2256 gst_element_query_duration (GstElement * element, GstFormat format,
2262 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
2263 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2265 query = gst_query_new_duration (format);
2266 ret = gst_element_query (element, query);
2269 gst_query_parse_duration (query, NULL, duration);
2271 gst_query_unref (query);
2277 * gst_element_query_convert:
2278 * @element: a #GstElement to invoke the convert query on.
2279 * @src_format: (inout): a #GstFormat to convert from.
2280 * @src_val: a value to convert.
2281 * @dest_format: the #GstFormat to convert to.
2282 * @dest_val: (out): a pointer to the result.
2284 * Queries an element to convert @src_val in @src_format to @dest_format.
2286 * Returns: %TRUE if the query could be performed.
2289 gst_element_query_convert (GstElement * element, GstFormat src_format,
2290 gint64 src_val, GstFormat dest_format, gint64 * dest_val)
2295 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
2296 g_return_val_if_fail (dest_format != GST_FORMAT_UNDEFINED, FALSE);
2297 g_return_val_if_fail (dest_val != NULL, FALSE);
2299 if (dest_format == src_format || src_val == -1) {
2300 *dest_val = src_val;
2304 query = gst_query_new_convert (src_format, src_val, dest_format);
2305 ret = gst_element_query (element, query);
2308 gst_query_parse_convert (query, NULL, NULL, NULL, dest_val);
2310 gst_query_unref (query);
2316 * gst_element_seek_simple:
2317 * @element: a #GstElement to seek on
2318 * @format: a #GstFormat to execute the seek in, such as #GST_FORMAT_TIME
2319 * @seek_flags: seek options; playback applications will usually want to use
2320 * GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_KEY_UNIT here
2321 * @seek_pos: position to seek to (relative to the start); if you are doing
2322 * a seek in #GST_FORMAT_TIME this value is in nanoseconds -
2323 * multiply with #GST_SECOND to convert seconds to nanoseconds or
2324 * with #GST_MSECOND to convert milliseconds to nanoseconds.
2326 * Simple API to perform a seek on the given element, meaning it just seeks
2327 * to the given position relative to the start of the stream. For more complex
2328 * operations like segment seeks (e.g. for looping) or changing the playback
2329 * rate or seeking relative to the last configured playback segment you should
2330 * use gst_element_seek().
2332 * In a completely prerolled PAUSED or PLAYING pipeline, seeking is always
2333 * guaranteed to return %TRUE on a seekable media type or %FALSE when the media
2334 * type is certainly not seekable (such as a live stream).
2336 * Some elements allow for seeking in the READY state, in this
2337 * case they will store the seek event and execute it when they are put to
2338 * PAUSED. If the element supports seek in READY, it will always return %TRUE when
2339 * it receives the event in the READY state.
2341 * Returns: %TRUE if the seek operation succeeded. Flushing seeks will trigger a
2342 * preroll, which will emit %GST_MESSAGE_ASYNC_DONE.
2345 gst_element_seek_simple (GstElement * element, GstFormat format,
2346 GstSeekFlags seek_flags, gint64 seek_pos)
2348 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
2349 g_return_val_if_fail (seek_pos >= 0, FALSE);
2351 return gst_element_seek (element, 1.0, format, seek_flags,
2352 GST_SEEK_TYPE_SET, seek_pos, GST_SEEK_TYPE_NONE, 0);
2356 * gst_pad_use_fixed_caps:
2357 * @pad: the pad to use
2359 * A helper function you can use that sets the FIXED_CAPS flag
2360 * This way the default CAPS query will always return the negotiated caps
2361 * or in case the pad is not negotiated, the padtemplate caps.
2363 * The negotiated caps are the caps of the last CAPS event that passed on the
2364 * pad. Use this function on a pad that, once it negotiated to a CAPS, cannot
2365 * be renegotiated to something else.
2368 gst_pad_use_fixed_caps (GstPad * pad)
2370 GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_FIXED_CAPS);
2374 * gst_pad_get_parent_element:
2377 * Gets the parent of @pad, cast to a #GstElement. If a @pad has no parent or
2378 * its parent is not an element, return %NULL.
2380 * Returns: (transfer full) (nullable): the parent of the pad. The
2381 * caller has a reference on the parent, so unref when you're finished
2387 gst_pad_get_parent_element (GstPad * pad)
2391 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2393 p = gst_object_get_parent (GST_OBJECT_CAST (pad));
2395 if (p && !GST_IS_ELEMENT (p)) {
2396 gst_object_unref (p);
2399 return GST_ELEMENT_CAST (p);
2403 * gst_object_default_error:
2404 * @source: the #GstObject that initiated the error.
2405 * @error: (in): the GError.
2406 * @debug: (in) (allow-none): an additional debug information string, or %NULL
2408 * A default error function that uses g_printerr() to display the error message
2409 * and the optional debug sting..
2411 * The default handler will simply print the error string using g_print.
2414 gst_object_default_error (GstObject * source, const GError * error,
2415 const gchar * debug)
2417 gchar *name = gst_object_get_path_string (source);
2419 g_printerr (_("ERROR: from element %s: %s\n"), name, error->message);
2421 g_printerr (_("Additional debug info:\n%s\n"), debug);
2429 * @element_1: (transfer full): the #GstElement element to add to the bin
2430 * @...: (transfer full): additional elements to add to the bin
2432 * Adds a %NULL-terminated list of elements to a bin. This function is
2433 * equivalent to calling gst_bin_add() for each member of the list. The return
2434 * value of each gst_bin_add() is ignored.
2437 gst_bin_add_many (GstBin * bin, GstElement * element_1, ...)
2441 g_return_if_fail (GST_IS_BIN (bin));
2442 g_return_if_fail (GST_IS_ELEMENT (element_1));
2444 va_start (args, element_1);
2447 gst_bin_add (bin, element_1);
2449 element_1 = va_arg (args, GstElement *);
2456 * gst_bin_remove_many:
2458 * @element_1: (transfer none): the first #GstElement to remove from the bin
2459 * @...: (transfer none): %NULL-terminated list of elements to remove from the bin
2461 * Remove a list of elements from a bin. This function is equivalent
2462 * to calling gst_bin_remove() with each member of the list.
2465 gst_bin_remove_many (GstBin * bin, GstElement * element_1, ...)
2469 g_return_if_fail (GST_IS_BIN (bin));
2470 g_return_if_fail (GST_IS_ELEMENT (element_1));
2472 va_start (args, element_1);
2475 gst_bin_remove (bin, element_1);
2477 element_1 = va_arg (args, GstElement *);
2487 } QueryAcceptCapsData;
2490 query_accept_caps_func (GstPad * pad, QueryAcceptCapsData * data)
2492 if (G_LIKELY (gst_pad_peer_query (pad, data->query))) {
2495 gst_query_parse_accept_caps_result (data->query, &result);
2496 data->ret &= result;
2502 * gst_pad_proxy_query_accept_caps:
2503 * @pad: a #GstPad to proxy.
2504 * @query: an ACCEPT_CAPS #GstQuery.
2506 * Checks if all internally linked pads of @pad accepts the caps in @query and
2507 * returns the intersection of the results.
2509 * This function is useful as a default accept caps query function for an element
2510 * that can handle any stream format, but requires caps that are acceptable for
2511 * all opposite pads.
2513 * Returns: %TRUE if @query could be executed
2516 gst_pad_proxy_query_accept_caps (GstPad * pad, GstQuery * query)
2518 QueryAcceptCapsData data;
2520 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2521 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2522 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ACCEPT_CAPS, FALSE);
2524 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2525 "proxying accept caps query for %s:%s", GST_DEBUG_PAD_NAME (pad));
2528 /* value to hold the return, by default it holds TRUE */
2529 /* FIXME: TRUE is wrong when there are no pads */
2532 gst_pad_forward (pad, (GstPadForwardFunction) query_accept_caps_func, &data);
2533 gst_query_set_accept_caps_result (query, data.ret);
2535 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "proxying accept caps query: %d",
2548 query_caps_func (GstPad * pad, QueryCapsData * data)
2550 gboolean empty = FALSE;
2552 if (G_LIKELY (gst_pad_peer_query (pad, data->query))) {
2553 GstCaps *peercaps, *intersection;
2555 gst_query_parse_caps_result (data->query, &peercaps);
2556 GST_DEBUG_OBJECT (pad, "intersect with result %" GST_PTR_FORMAT, peercaps);
2557 intersection = gst_caps_intersect (data->ret, peercaps);
2558 GST_DEBUG_OBJECT (pad, "intersected %" GST_PTR_FORMAT, intersection);
2560 gst_caps_unref (data->ret);
2561 data->ret = intersection;
2563 /* stop when empty */
2564 empty = gst_caps_is_empty (intersection);
2570 * gst_pad_proxy_query_caps:
2571 * @pad: a #GstPad to proxy.
2572 * @query: a CAPS #GstQuery.
2574 * Calls gst_pad_query_caps() for all internally linked pads of @pad and returns
2575 * the intersection of the results.
2577 * This function is useful as a default caps query function for an element
2578 * that can handle any stream format, but requires all its pads to have
2579 * the same caps. Two such elements are tee and adder.
2581 * Returns: %TRUE if @query could be executed
2584 gst_pad_proxy_query_caps (GstPad * pad, GstQuery * query)
2586 GstCaps *filter, *templ, *result;
2589 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2590 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2591 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CAPS, FALSE);
2593 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "proxying caps query for %s:%s",
2594 GST_DEBUG_PAD_NAME (pad));
2598 /* value to hold the return, by default it holds the filter or ANY */
2599 gst_query_parse_caps (query, &filter);
2600 data.ret = filter ? gst_caps_ref (filter) : gst_caps_new_any ();
2602 gst_pad_forward (pad, (GstPadForwardFunction) query_caps_func, &data);
2604 templ = gst_pad_get_pad_template_caps (pad);
2605 result = gst_caps_intersect (data.ret, templ);
2606 gst_caps_unref (data.ret);
2607 gst_caps_unref (templ);
2609 gst_query_set_caps_result (query, result);
2610 gst_caps_unref (result);
2612 /* FIXME: return something depending on the processing */
2617 * gst_pad_query_position:
2618 * @pad: a #GstPad to invoke the position query on.
2619 * @format: the #GstFormat requested
2620 * @cur: (out) (allow-none): A location in which to store the current position, or %NULL.
2622 * Queries a pad for the stream position.
2624 * Returns: %TRUE if the query could be performed.
2627 gst_pad_query_position (GstPad * pad, GstFormat format, gint64 * cur)
2632 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2633 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2635 query = gst_query_new_position (format);
2636 if ((ret = gst_pad_query (pad, query)))
2637 gst_query_parse_position (query, NULL, cur);
2638 gst_query_unref (query);
2644 * gst_pad_peer_query_position:
2645 * @pad: a #GstPad on whose peer to invoke the position query on.
2646 * Must be a sink pad.
2647 * @format: the #GstFormat requested
2648 * @cur: (out) (allow-none): a location in which to store the current
2649 * position, or %NULL.
2651 * Queries the peer of a given sink pad for the stream position.
2653 * Returns: %TRUE if the query could be performed.
2656 gst_pad_peer_query_position (GstPad * pad, GstFormat format, gint64 * cur)
2659 gboolean ret = FALSE;
2661 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2662 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2664 query = gst_query_new_position (format);
2665 if ((ret = gst_pad_peer_query (pad, query)))
2666 gst_query_parse_position (query, NULL, cur);
2667 gst_query_unref (query);
2673 * gst_pad_query_duration:
2674 * @pad: a #GstPad to invoke the duration query on.
2675 * @format: the #GstFormat requested
2676 * @duration: (out) (allow-none): a location in which to store the total
2677 * duration, or %NULL.
2679 * Queries a pad for the total stream duration.
2681 * Returns: %TRUE if the query could be performed.
2684 gst_pad_query_duration (GstPad * pad, GstFormat format, gint64 * duration)
2689 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2690 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2692 query = gst_query_new_duration (format);
2693 if ((ret = gst_pad_query (pad, query)))
2694 gst_query_parse_duration (query, NULL, duration);
2695 gst_query_unref (query);
2701 * gst_pad_peer_query_duration:
2702 * @pad: a #GstPad on whose peer pad to invoke the duration query on.
2703 * Must be a sink pad.
2704 * @format: the #GstFormat requested
2705 * @duration: (out) (allow-none): a location in which to store the total
2706 * duration, or %NULL.
2708 * Queries the peer pad of a given sink pad for the total stream duration.
2710 * Returns: %TRUE if the query could be performed.
2713 gst_pad_peer_query_duration (GstPad * pad, GstFormat format, gint64 * duration)
2716 gboolean ret = FALSE;
2718 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2719 g_return_val_if_fail (GST_PAD_IS_SINK (pad), FALSE);
2720 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2722 query = gst_query_new_duration (format);
2723 if ((ret = gst_pad_peer_query (pad, query)))
2724 gst_query_parse_duration (query, NULL, duration);
2725 gst_query_unref (query);
2731 * gst_pad_query_convert:
2732 * @pad: a #GstPad to invoke the convert query on.
2733 * @src_format: a #GstFormat to convert from.
2734 * @src_val: a value to convert.
2735 * @dest_format: the #GstFormat to convert to.
2736 * @dest_val: (out): a pointer to the result.
2738 * Queries a pad to convert @src_val in @src_format to @dest_format.
2740 * Returns: %TRUE if the query could be performed.
2743 gst_pad_query_convert (GstPad * pad, GstFormat src_format, gint64 src_val,
2744 GstFormat dest_format, gint64 * dest_val)
2749 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2750 g_return_val_if_fail (dest_format != GST_FORMAT_UNDEFINED, FALSE);
2751 g_return_val_if_fail (dest_val != NULL, FALSE);
2753 if (dest_format == src_format || src_val == -1) {
2754 *dest_val = src_val;
2758 query = gst_query_new_convert (src_format, src_val, dest_format);
2759 if ((ret = gst_pad_query (pad, query)))
2760 gst_query_parse_convert (query, NULL, NULL, NULL, dest_val);
2761 gst_query_unref (query);
2767 * gst_pad_peer_query_convert:
2768 * @pad: a #GstPad, on whose peer pad to invoke the convert query on.
2769 * Must be a sink pad.
2770 * @src_format: a #GstFormat to convert from.
2771 * @src_val: a value to convert.
2772 * @dest_format: the #GstFormat to convert to.
2773 * @dest_val: (out): a pointer to the result.
2775 * Queries the peer pad of a given sink pad to convert @src_val in @src_format
2778 * Returns: %TRUE if the query could be performed.
2781 gst_pad_peer_query_convert (GstPad * pad, GstFormat src_format, gint64 src_val,
2782 GstFormat dest_format, gint64 * dest_val)
2785 gboolean ret = FALSE;
2787 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2788 g_return_val_if_fail (GST_PAD_IS_SINK (pad), FALSE);
2789 g_return_val_if_fail (dest_format != GST_FORMAT_UNDEFINED, FALSE);
2790 g_return_val_if_fail (dest_val != NULL, FALSE);
2792 query = gst_query_new_convert (src_format, src_val, dest_format);
2793 if ((ret = gst_pad_peer_query (pad, query)))
2794 gst_query_parse_convert (query, NULL, NULL, NULL, dest_val);
2795 gst_query_unref (query);
2801 * gst_pad_query_caps:
2802 * @pad: a #GstPad to get the capabilities of.
2803 * @filter: (allow-none): suggested #GstCaps, or %NULL
2805 * Gets the capabilities this pad can produce or consume.
2806 * Note that this method doesn't necessarily return the caps set by sending a
2807 * gst_event_new_caps() - use gst_pad_get_current_caps() for that instead.
2808 * gst_pad_query_caps returns all possible caps a pad can operate with, using
2809 * the pad's CAPS query function, If the query fails, this function will return
2810 * @filter, if not %NULL, otherwise ANY.
2812 * When called on sinkpads @filter contains the caps that
2813 * upstream could produce in the order preferred by upstream. When
2814 * called on srcpads @filter contains the caps accepted by
2815 * downstream in the preferred order. @filter might be %NULL but
2816 * if it is not %NULL the returned caps will be a subset of @filter.
2818 * Note that this function does not return writable #GstCaps, use
2819 * gst_caps_make_writable() before modifying the caps.
2821 * Returns: (transfer full): the caps of the pad with incremented ref-count.
2824 gst_pad_query_caps (GstPad * pad, GstCaps * filter)
2826 GstCaps *result = NULL;
2829 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2830 g_return_val_if_fail (filter == NULL || GST_IS_CAPS (filter), NULL);
2832 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2833 "get pad caps with filter %" GST_PTR_FORMAT, filter);
2835 query = gst_query_new_caps (filter);
2836 if (gst_pad_query (pad, query)) {
2837 gst_query_parse_caps_result (query, &result);
2838 gst_caps_ref (result);
2839 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2840 "query returned %" GST_PTR_FORMAT, result);
2841 } else if (filter) {
2842 result = gst_caps_ref (filter);
2844 result = gst_caps_new_any ();
2846 gst_query_unref (query);
2852 * gst_pad_peer_query_caps:
2853 * @pad: a #GstPad to get the capabilities of.
2854 * @filter: (allow-none): a #GstCaps filter, or %NULL.
2856 * Gets the capabilities of the peer connected to this pad. Similar to
2857 * gst_pad_query_caps().
2859 * When called on srcpads @filter contains the caps that
2860 * upstream could produce in the order preferred by upstream. When
2861 * called on sinkpads @filter contains the caps accepted by
2862 * downstream in the preferred order. @filter might be %NULL but
2863 * if it is not %NULL the returned caps will be a subset of @filter.
2865 * Returns: the caps of the peer pad with incremented ref-count. When there is
2866 * no peer pad, this function returns @filter or, when @filter is %NULL, ANY
2870 gst_pad_peer_query_caps (GstPad * pad, GstCaps * filter)
2872 GstCaps *result = NULL;
2875 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2876 g_return_val_if_fail (filter == NULL || GST_IS_CAPS (filter), NULL);
2878 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2879 "get pad peer caps with filter %" GST_PTR_FORMAT, filter);
2881 query = gst_query_new_caps (filter);
2882 if (gst_pad_peer_query (pad, query)) {
2883 gst_query_parse_caps_result (query, &result);
2884 gst_caps_ref (result);
2885 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2886 "peer query returned %" GST_PTR_FORMAT, result);
2887 } else if (filter) {
2888 result = gst_caps_ref (filter);
2890 result = gst_caps_new_any ();
2892 gst_query_unref (query);
2898 * gst_pad_query_accept_caps:
2899 * @pad: a #GstPad to check
2900 * @caps: a #GstCaps to check on the pad
2902 * Check if the given pad accepts the caps.
2904 * Returns: %TRUE if the pad can accept the caps.
2907 gst_pad_query_accept_caps (GstPad * pad, GstCaps * caps)
2909 gboolean res = TRUE;
2912 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2913 g_return_val_if_fail (GST_IS_CAPS (caps), FALSE);
2915 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %"
2916 GST_PTR_FORMAT, caps);
2918 query = gst_query_new_accept_caps (caps);
2919 if (gst_pad_query (pad, query)) {
2920 gst_query_parse_accept_caps_result (query, &res);
2921 GST_DEBUG_OBJECT (pad, "query returned %d", res);
2923 gst_query_unref (query);
2929 * gst_pad_peer_query_accept_caps:
2930 * @pad: a #GstPad to check the peer of
2931 * @caps: a #GstCaps to check on the pad
2933 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2936 * Returns: %TRUE if the peer of @pad can accept the caps or @pad has no peer.
2939 gst_pad_peer_query_accept_caps (GstPad * pad, GstCaps * caps)
2941 gboolean res = TRUE;
2944 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2945 g_return_val_if_fail (GST_IS_CAPS (caps), FALSE);
2947 query = gst_query_new_accept_caps (caps);
2948 if (gst_pad_peer_query (pad, query)) {
2949 gst_query_parse_accept_caps_result (query, &res);
2950 GST_DEBUG_OBJECT (pad, "query returned %d", res);
2952 gst_query_unref (query);
2958 element_find_unlinked_pad (GstElement * element, GstPadDirection direction)
2961 GstPad *unlinked_pad = NULL;
2963 GValue data = { 0, };
2965 switch (direction) {
2967 iter = gst_element_iterate_src_pads (element);
2970 iter = gst_element_iterate_sink_pads (element);
2973 g_return_val_if_reached (NULL);
2978 switch (gst_iterator_next (iter, &data)) {
2979 case GST_ITERATOR_OK:{
2981 GstPad *pad = g_value_get_object (&data);
2983 GST_CAT_LOG (GST_CAT_ELEMENT_PADS, "examining pad %s:%s",
2984 GST_DEBUG_PAD_NAME (pad));
2986 peer = gst_pad_get_peer (pad);
2988 unlinked_pad = gst_object_ref (pad);
2990 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
2991 "found existing unlinked pad %s:%s",
2992 GST_DEBUG_PAD_NAME (unlinked_pad));
2994 gst_object_unref (peer);
2996 g_value_reset (&data);
2999 case GST_ITERATOR_DONE:
3002 case GST_ITERATOR_RESYNC:
3003 gst_iterator_resync (iter);
3005 case GST_ITERATOR_ERROR:
3006 g_return_val_if_reached (NULL);
3010 g_value_unset (&data);
3011 gst_iterator_free (iter);
3013 return unlinked_pad;
3017 * gst_bin_find_unlinked_pad:
3018 * @bin: bin in which to look for elements with unlinked pads
3019 * @direction: whether to look for an unlinked source or sink pad
3021 * Recursively looks for elements with an unlinked pad of the given
3022 * direction within the specified bin and returns an unlinked pad
3023 * if one is found, or %NULL otherwise. If a pad is found, the caller
3024 * owns a reference to it and should use gst_object_unref() on the
3025 * pad when it is not needed any longer.
3027 * Returns: (transfer full) (nullable): unlinked pad of the given
3031 gst_bin_find_unlinked_pad (GstBin * bin, GstPadDirection direction)
3036 GValue data = { 0, };
3038 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
3039 g_return_val_if_fail (direction != GST_PAD_UNKNOWN, NULL);
3042 iter = gst_bin_iterate_recurse (bin);
3044 switch (gst_iterator_next (iter, &data)) {
3045 case GST_ITERATOR_OK:{
3046 GstElement *element = g_value_get_object (&data);
3048 pad = element_find_unlinked_pad (element, direction);
3051 g_value_reset (&data);
3054 case GST_ITERATOR_DONE:
3057 case GST_ITERATOR_RESYNC:
3058 gst_iterator_resync (iter);
3060 case GST_ITERATOR_ERROR:
3061 g_return_val_if_reached (NULL);
3065 g_value_unset (&data);
3066 gst_iterator_free (iter);
3072 * gst_parse_bin_from_description:
3073 * @bin_description: command line describing the bin
3074 * @ghost_unlinked_pads: whether to automatically create ghost pads
3075 * for unlinked source or sink pads within the bin
3076 * @err: where to store the error message in case of an error, or %NULL
3078 * This is a convenience wrapper around gst_parse_launch() to create a
3079 * #GstBin from a gst-launch-style pipeline description. See
3080 * gst_parse_launch() and the gst-launch man page for details about the
3081 * syntax. Ghost pads on the bin for unlinked source or sink pads
3082 * within the bin can automatically be created (but only a maximum of
3083 * one ghost pad for each direction will be created; if you expect
3084 * multiple unlinked source pads or multiple unlinked sink pads
3085 * and want them all ghosted, you will have to create the ghost pads
3088 * Returns: (transfer floating) (type Gst.Bin) (nullable): a
3089 * newly-created bin, or %NULL if an error occurred.
3092 gst_parse_bin_from_description (const gchar * bin_description,
3093 gboolean ghost_unlinked_pads, GError ** err)
3095 return gst_parse_bin_from_description_full (bin_description,
3096 ghost_unlinked_pads, NULL, GST_PARSE_FLAG_NONE, err);
3100 * gst_parse_bin_from_description_full:
3101 * @bin_description: command line describing the bin
3102 * @ghost_unlinked_pads: whether to automatically create ghost pads
3103 * for unlinked source or sink pads within the bin
3104 * @context: (transfer none) (allow-none): a parse context allocated with
3105 * gst_parse_context_new(), or %NULL
3106 * @flags: parsing options, or #GST_PARSE_FLAG_NONE
3107 * @err: where to store the error message in case of an error, or %NULL
3109 * This is a convenience wrapper around gst_parse_launch() to create a
3110 * #GstBin from a gst-launch-style pipeline description. See
3111 * gst_parse_launch() and the gst-launch man page for details about the
3112 * syntax. Ghost pads on the bin for unlinked source or sink pads
3113 * within the bin can automatically be created (but only a maximum of
3114 * one ghost pad for each direction will be created; if you expect
3115 * multiple unlinked source pads or multiple unlinked sink pads
3116 * and want them all ghosted, you will have to create the ghost pads
3119 * Returns: (transfer floating) (type Gst.Element): a newly-created
3120 * element, which is guaranteed to be a bin unless
3121 * GST_FLAG_NO_SINGLE_ELEMENT_BINS was passed, or %NULL if an error
3125 gst_parse_bin_from_description_full (const gchar * bin_description,
3126 gboolean ghost_unlinked_pads, GstParseContext * context,
3127 GstParseFlags flags, GError ** err)
3129 #ifndef GST_DISABLE_PARSE
3131 GstElement *element;
3135 g_return_val_if_fail (bin_description != NULL, NULL);
3136 g_return_val_if_fail (err == NULL || *err == NULL, NULL);
3138 GST_DEBUG ("Making bin from description '%s'", bin_description);
3140 /* parse the pipeline to a bin */
3141 if (flags & GST_PARSE_FLAG_NO_SINGLE_ELEMENT_BINS) {
3142 element = gst_parse_launch_full (bin_description, context, flags, err);
3144 desc = g_strdup_printf ("bin.( %s )", bin_description);
3145 element = gst_parse_launch_full (desc, context, flags, err);
3149 if (element == NULL || (err && *err != NULL)) {
3151 gst_object_unref (element);
3155 if (GST_IS_BIN (element)) {
3156 bin = GST_BIN (element);
3161 /* find pads and ghost them if necessary */
3162 if (ghost_unlinked_pads) {
3163 if ((pad = gst_bin_find_unlinked_pad (bin, GST_PAD_SRC))) {
3164 gst_element_add_pad (GST_ELEMENT (bin), gst_ghost_pad_new ("src", pad));
3165 gst_object_unref (pad);
3167 if ((pad = gst_bin_find_unlinked_pad (bin, GST_PAD_SINK))) {
3168 gst_element_add_pad (GST_ELEMENT (bin), gst_ghost_pad_new ("sink", pad));
3169 gst_object_unref (pad);
3173 return GST_ELEMENT (bin);
3177 GST_WARNING ("Disabled API called");
3179 msg = gst_error_get_message (GST_CORE_ERROR, GST_CORE_ERROR_DISABLED);
3180 g_set_error (err, GST_CORE_ERROR, GST_CORE_ERROR_DISABLED, "%s", msg);
3188 * gst_util_get_timestamp:
3190 * Get a timestamp as GstClockTime to be used for interval measurements.
3191 * The timestamp should not be interpreted in any other way.
3193 * Returns: the timestamp
3196 gst_util_get_timestamp (void)
3198 #if defined (HAVE_POSIX_TIMERS) && defined(HAVE_MONOTONIC_CLOCK) &&\
3199 defined (HAVE_CLOCK_GETTIME)
3200 struct timespec now;
3202 clock_gettime (CLOCK_MONOTONIC, &now);
3203 return GST_TIMESPEC_TO_TIME (now);
3207 g_get_current_time (&now);
3208 return GST_TIMEVAL_TO_TIME (now);
3213 * gst_util_array_binary_search:
3214 * @array: the sorted input array
3215 * @num_elements: number of elements in the array
3216 * @element_size: size of every element in bytes
3217 * @search_func: (scope call): function to compare two elements, @search_data will always be passed as second argument
3218 * @mode: search mode that should be used
3219 * @search_data: element that should be found
3220 * @user_data: (closure): data to pass to @search_func
3222 * Searches inside @array for @search_data by using the comparison function
3223 * @search_func. @array must be sorted ascending.
3225 * As @search_data is always passed as second argument to @search_func it's
3226 * not required that @search_data has the same type as the array elements.
3228 * The complexity of this search function is O(log (num_elements)).
3230 * Returns: (transfer none) (nullable): The address of the found
3231 * element or %NULL if nothing was found
3234 gst_util_array_binary_search (gpointer array, guint num_elements,
3235 gsize element_size, GCompareDataFunc search_func, GstSearchMode mode,
3236 gconstpointer search_data, gpointer user_data)
3238 glong left = 0, right = num_elements - 1, m;
3240 guint8 *data = (guint8 *) array;
3242 g_return_val_if_fail (array != NULL, NULL);
3243 g_return_val_if_fail (element_size > 0, NULL);
3244 g_return_val_if_fail (search_func != NULL, NULL);
3246 /* 0. No elements => return NULL */
3247 if (num_elements == 0)
3250 /* 1. If search_data is before the 0th element return the 0th element */
3251 ret = search_func (data, search_data, user_data);
3252 if ((ret >= 0 && mode == GST_SEARCH_MODE_AFTER) || ret == 0)
3257 /* 2. If search_data is after the last element return the last element */
3259 search_func (data + (num_elements - 1) * element_size, search_data,
3261 if ((ret <= 0 && mode == GST_SEARCH_MODE_BEFORE) || ret == 0)
3262 return data + (num_elements - 1) * element_size;
3266 /* 3. else binary search */
3268 m = left + (right - left) / 2;
3270 ret = search_func (data + m * element_size, search_data, user_data);
3273 return data + m * element_size;
3274 } else if (ret < 0) {
3280 /* No exact match found */
3282 if (mode == GST_SEARCH_MODE_EXACT) {
3284 } else if (mode == GST_SEARCH_MODE_AFTER) {
3286 return (m < num_elements) ? data + (m + 1) * element_size : NULL;
3288 return data + m * element_size;
3291 return data + m * element_size;
3293 return (m > 0) ? data + (m - 1) * element_size : NULL;
3299 /* Finds the greatest common divisor.
3300 * Returns 1 if none other found.
3301 * This is Euclid's algorithm. */
3304 * gst_util_greatest_common_divisor:
3305 * @a: First value as #gint
3306 * @b: Second value as #gint
3308 * Calculates the greatest common divisor of @a
3311 * Returns: Greatest common divisor of @a and @b
3314 gst_util_greatest_common_divisor (gint a, gint b)
3327 * gst_util_greatest_common_divisor_int64:
3328 * @a: First value as #gint64
3329 * @b: Second value as #gint64
3331 * Calculates the greatest common divisor of @a
3334 * Returns: Greatest common divisor of @a and @b
3337 gst_util_greatest_common_divisor_int64 (gint64 a, gint64 b)
3351 * gst_util_fraction_to_double:
3352 * @src_n: Fraction numerator as #gint
3353 * @src_d: Fraction denominator #gint
3354 * @dest: (out): pointer to a #gdouble for the result
3356 * Transforms a fraction to a #gdouble.
3359 gst_util_fraction_to_double (gint src_n, gint src_d, gdouble * dest)
3361 g_return_if_fail (dest != NULL);
3362 g_return_if_fail (src_d != 0);
3364 *dest = ((gdouble) src_n) / ((gdouble) src_d);
3367 #define MAX_TERMS 30
3368 #define MIN_DIVISOR 1.0e-10
3369 #define MAX_ERROR 1.0e-20
3371 /* use continued fractions to transform a double into a fraction,
3372 * see http://mathforum.org/dr.math/faq/faq.fractions.html#decfrac.
3373 * This algorithm takes care of overflows.
3377 * gst_util_double_to_fraction:
3378 * @src: #gdouble to transform
3379 * @dest_n: (out): pointer to a #gint to hold the result numerator
3380 * @dest_d: (out): pointer to a #gint to hold the result denominator
3382 * Transforms a #gdouble to a fraction and simplifies
3386 gst_util_double_to_fraction (gdouble src, gint * dest_n, gint * dest_d)
3389 gdouble V, F; /* double being converted */
3390 gint N, D; /* will contain the result */
3391 gint A; /* current term in continued fraction */
3392 gint64 N1, D1; /* numerator, denominator of last approx */
3393 gint64 N2, D2; /* numerator, denominator of previous approx */
3396 gboolean negative = FALSE;
3398 g_return_if_fail (dest_n != NULL);
3399 g_return_if_fail (dest_d != NULL);
3401 /* initialize fraction being converted */
3409 /* initialize fractions with 1/0, 0/1 */
3417 for (i = 0; i < MAX_TERMS; i++) {
3419 A = (gint) F; /* no floor() needed, F is always >= 0 */
3420 /* get new divisor */
3423 /* calculate new fraction in temp */
3427 /* guard against overflow */
3428 if (N2 > G_MAXINT || D2 > G_MAXINT) {
3435 /* save last two fractions */
3441 /* quit if dividing by zero or close enough to target */
3442 if (F < MIN_DIVISOR || fabs (V - ((gdouble) N) / D) < MAX_ERROR) {
3446 /* Take reciprocal */
3449 /* fix for overflow */
3454 /* fix for negative */
3459 gcd = gst_util_greatest_common_divisor (N, D);
3471 * gst_util_fraction_multiply:
3472 * @a_n: Numerator of first value
3473 * @a_d: Denominator of first value
3474 * @b_n: Numerator of second value
3475 * @b_d: Denominator of second value
3476 * @res_n: (out): Pointer to #gint to hold the result numerator
3477 * @res_d: (out): Pointer to #gint to hold the result denominator
3479 * Multiplies the fractions @a_n/@a_d and @b_n/@b_d and stores
3480 * the result in @res_n and @res_d.
3482 * Returns: %FALSE on overflow, %TRUE otherwise.
3485 gst_util_fraction_multiply (gint a_n, gint a_d, gint b_n, gint b_d,
3486 gint * res_n, gint * res_d)
3490 g_return_val_if_fail (res_n != NULL, FALSE);
3491 g_return_val_if_fail (res_d != NULL, FALSE);
3492 g_return_val_if_fail (a_d != 0, FALSE);
3493 g_return_val_if_fail (b_d != 0, FALSE);
3495 /* early out if either is 0, as its gcd would be 0 */
3496 if (a_n == 0 || b_n == 0) {
3502 gcd = gst_util_greatest_common_divisor (a_n, a_d);
3506 gcd = gst_util_greatest_common_divisor (b_n, b_d);
3510 gcd = gst_util_greatest_common_divisor (a_n, b_d);
3514 gcd = gst_util_greatest_common_divisor (a_d, b_n);
3518 /* This would result in overflow */
3519 if (a_n != 0 && G_MAXINT / ABS (a_n) < ABS (b_n))
3521 if (G_MAXINT / ABS (a_d) < ABS (b_d))
3527 gcd = gst_util_greatest_common_divisor (*res_n, *res_d);
3535 * gst_util_fraction_add:
3536 * @a_n: Numerator of first value
3537 * @a_d: Denominator of first value
3538 * @b_n: Numerator of second value
3539 * @b_d: Denominator of second value
3540 * @res_n: (out): Pointer to #gint to hold the result numerator
3541 * @res_d: (out): Pointer to #gint to hold the result denominator
3543 * Adds the fractions @a_n/@a_d and @b_n/@b_d and stores
3544 * the result in @res_n and @res_d.
3546 * Returns: %FALSE on overflow, %TRUE otherwise.
3549 gst_util_fraction_add (gint a_n, gint a_d, gint b_n, gint b_d, gint * res_n,
3554 g_return_val_if_fail (res_n != NULL, FALSE);
3555 g_return_val_if_fail (res_d != NULL, FALSE);
3556 g_return_val_if_fail (a_d != 0, FALSE);
3557 g_return_val_if_fail (b_d != 0, FALSE);
3559 gcd = gst_util_greatest_common_divisor (a_n, a_d);
3563 gcd = gst_util_greatest_common_divisor (b_n, b_d);
3578 /* This would result in overflow */
3579 if (G_MAXINT / ABS (a_n) < ABS (b_n))
3581 if (G_MAXINT / ABS (a_d) < ABS (b_d))
3583 if (G_MAXINT / ABS (a_d) < ABS (b_d))
3586 *res_n = (a_n * b_d) + (a_d * b_n);
3589 gcd = gst_util_greatest_common_divisor (*res_n, *res_d);
3602 * gst_util_fraction_compare:
3603 * @a_n: Numerator of first value
3604 * @a_d: Denominator of first value
3605 * @b_n: Numerator of second value
3606 * @b_d: Denominator of second value
3608 * Compares the fractions @a_n/@a_d and @b_n/@b_d and returns
3609 * -1 if a < b, 0 if a = b and 1 if a > b.
3611 * Returns: -1 if a < b; 0 if a = b; 1 if a > b.
3614 gst_util_fraction_compare (gint a_n, gint a_d, gint b_n, gint b_d)
3620 g_return_val_if_fail (a_d != 0 && b_d != 0, 0);
3623 gcd = gst_util_greatest_common_divisor (a_n, a_d);
3627 gcd = gst_util_greatest_common_divisor (b_n, b_d);
3631 /* fractions are reduced when set, so we can quickly see if they're equal */
3632 if (a_n == b_n && a_d == b_d)
3635 /* extend to 64 bits */
3636 new_num_1 = ((gint64) a_n) * b_d;
3637 new_num_2 = ((gint64) b_n) * a_d;
3638 if (new_num_1 < new_num_2)
3640 if (new_num_1 > new_num_2)
3643 /* Should not happen because a_d and b_d are not 0 */
3644 g_return_val_if_reached (0);
3648 gst_pad_create_stream_id_internal (GstPad * pad, GstElement * parent,
3649 const gchar * stream_id)
3651 GstEvent *upstream_event;
3652 gchar *upstream_stream_id = NULL, *new_stream_id;
3655 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3656 g_return_val_if_fail (GST_PAD_IS_SRC (pad), NULL);
3657 g_return_val_if_fail (GST_IS_ELEMENT (parent), NULL);
3659 g_return_val_if_fail (parent->numsinkpads <= 1, NULL);
3661 /* If the element has multiple source pads it must
3662 * provide a stream-id for every source pad, otherwise
3663 * all source pads will have the same and are not
3664 * distinguishable */
3665 g_return_val_if_fail (parent->numsrcpads <= 1 || stream_id, NULL);
3667 /* First try to get the upstream stream-start stream-id from the sinkpad.
3668 * This will only work for non-source elements */
3669 sinkpad = gst_element_get_static_pad (parent, "sink");
3672 gst_pad_get_sticky_event (sinkpad, GST_EVENT_STREAM_START, 0);
3673 if (upstream_event) {
3676 gst_event_parse_stream_start (upstream_event, &tmp);
3678 upstream_stream_id = g_strdup (tmp);
3679 gst_event_unref (upstream_event);
3681 gst_object_unref (sinkpad);
3684 /* The only case where we don't have an upstream start-start event
3685 * here is for source elements */
3686 if (!upstream_stream_id) {
3690 /* Try to generate one from the URI query and
3691 * if it fails take a random number instead */
3692 query = gst_query_new_uri ();
3693 if (gst_element_query (parent, query)) {
3694 gst_query_parse_uri (query, &uri);
3700 /* And then generate an SHA256 sum of the URI */
3701 cs = g_checksum_new (G_CHECKSUM_SHA256);
3702 g_checksum_update (cs, (const guchar *) uri, strlen (uri));
3704 upstream_stream_id = g_strdup (g_checksum_get_string (cs));
3705 g_checksum_free (cs);
3707 /* Just get some random number if the URI query fails */
3708 GST_FIXME_OBJECT (pad, "Creating random stream-id, consider "
3709 "implementing a deterministic way of creating a stream-id");
3710 upstream_stream_id =
3711 g_strdup_printf ("%08x%08x%08x%08x", g_random_int (), g_random_int (),
3712 g_random_int (), g_random_int ());
3715 gst_query_unref (query);
3719 new_stream_id = g_strconcat (upstream_stream_id, "/", stream_id, NULL);
3721 new_stream_id = g_strdup (upstream_stream_id);
3724 g_free (upstream_stream_id);
3726 return new_stream_id;
3730 * gst_pad_create_stream_id_printf_valist:
3731 * @pad: A source #GstPad
3732 * @parent: Parent #GstElement of @pad
3733 * @stream_id: (allow-none): The stream-id
3734 * @var_args: parameters for the @stream_id format string
3736 * Creates a stream-id for the source #GstPad @pad by combining the
3737 * upstream information with the optional @stream_id of the stream
3738 * of @pad. @pad must have a parent #GstElement and which must have zero
3739 * or one sinkpad. @stream_id can only be %NULL if the parent element
3740 * of @pad has only a single source pad.
3742 * This function generates an unique stream-id by getting the upstream
3743 * stream-start event stream ID and appending @stream_id to it. If the
3744 * element has no sinkpad it will generate an upstream stream-id by
3745 * doing an URI query on the element and in the worst case just uses
3746 * a random number. Source elements that don't implement the URI
3747 * handler interface should ideally generate a unique, deterministic
3748 * stream-id manually instead.
3750 * Returns: A stream-id for @pad. g_free() after usage.
3753 gst_pad_create_stream_id_printf_valist (GstPad * pad, GstElement * parent,
3754 const gchar * stream_id, va_list var_args)
3756 gchar *expanded = NULL, *new_stream_id;
3759 expanded = g_strdup_vprintf (stream_id, var_args);
3761 new_stream_id = gst_pad_create_stream_id_internal (pad, parent, expanded);
3765 return new_stream_id;
3769 * gst_pad_create_stream_id_printf:
3770 * @pad: A source #GstPad
3771 * @parent: Parent #GstElement of @pad
3772 * @stream_id: (allow-none): The stream-id
3773 * @...: parameters for the @stream_id format string
3775 * Creates a stream-id for the source #GstPad @pad by combining the
3776 * upstream information with the optional @stream_id of the stream
3777 * of @pad. @pad must have a parent #GstElement and which must have zero
3778 * or one sinkpad. @stream_id can only be %NULL if the parent element
3779 * of @pad has only a single source pad.
3781 * This function generates an unique stream-id by getting the upstream
3782 * stream-start event stream ID and appending @stream_id to it. If the
3783 * element has no sinkpad it will generate an upstream stream-id by
3784 * doing an URI query on the element and in the worst case just uses
3785 * a random number. Source elements that don't implement the URI
3786 * handler interface should ideally generate a unique, deterministic
3787 * stream-id manually instead.
3789 * Returns: A stream-id for @pad. g_free() after usage.
3792 gst_pad_create_stream_id_printf (GstPad * pad, GstElement * parent,
3793 const gchar * stream_id, ...)
3796 gchar *new_stream_id;
3798 va_start (var_args, stream_id);
3800 gst_pad_create_stream_id_printf_valist (pad, parent, stream_id, var_args);
3803 return new_stream_id;
3807 * gst_pad_create_stream_id:
3808 * @pad: A source #GstPad
3809 * @parent: Parent #GstElement of @pad
3810 * @stream_id: (allow-none): The stream-id
3812 * Creates a stream-id for the source #GstPad @pad by combining the
3813 * upstream information with the optional @stream_id of the stream
3814 * of @pad. @pad must have a parent #GstElement and which must have zero
3815 * or one sinkpad. @stream_id can only be %NULL if the parent element
3816 * of @pad has only a single source pad.
3818 * This function generates an unique stream-id by getting the upstream
3819 * stream-start event stream ID and appending @stream_id to it. If the
3820 * element has no sinkpad it will generate an upstream stream-id by
3821 * doing an URI query on the element and in the worst case just uses
3822 * a random number. Source elements that don't implement the URI
3823 * handler interface should ideally generate a unique, deterministic
3824 * stream-id manually instead.
3826 * Since stream IDs are sorted alphabetically, any numbers in the
3827 * stream ID should be printed with a fixed number of characters,
3828 * preceded by 0's, such as by using the format \%03u instead of \%u.
3830 * Returns: A stream-id for @pad. g_free() after usage.
3833 gst_pad_create_stream_id (GstPad * pad, GstElement * parent,
3834 const gchar * stream_id)
3836 return gst_pad_create_stream_id_internal (pad, parent, stream_id);
3840 * gst_pad_get_stream_id:
3841 * @pad: A source #GstPad
3843 * Returns the current stream-id for the @pad, or %NULL if none has been
3844 * set yet, i.e. the pad has not received a stream-start event yet.
3846 * This is a convenience wrapper around gst_pad_get_sticky_event() and
3847 * gst_event_parse_stream_start().
3849 * The returned stream-id string should be treated as an opaque string, its
3850 * contents should not be interpreted.
3852 * Returns: (nullable): a newly-allocated copy of the stream-id for
3853 * @pad, or %NULL. g_free() the returned string when no longer
3859 gst_pad_get_stream_id (GstPad * pad)
3861 const gchar *stream_id = NULL;
3865 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3867 event = gst_pad_get_sticky_event (pad, GST_EVENT_STREAM_START, 0);
3868 if (event != NULL) {
3869 gst_event_parse_stream_start (event, &stream_id);
3870 ret = g_strdup (stream_id);
3871 gst_event_unref (event);
3872 GST_LOG_OBJECT (pad, "pad has stream-id '%s'", ret);
3874 GST_DEBUG_OBJECT (pad, "pad has not received a stream-start event yet");
3881 * gst_util_group_id_next:
3883 * Return a constantly incrementing group id.
3885 * This function is used to generate a new group-id for the
3886 * stream-start event.
3888 * Returns: A constantly incrementing unsigned integer, which might
3889 * overflow back to 0 at some point.
3892 gst_util_group_id_next (void)
3894 static gint counter = 0;
3895 return g_atomic_int_add (&counter, 1);