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., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, 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 * Convertes 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 (GST_VALUE_HOLDS_STRUCTURE (&v) && 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): a compatible #GstPadTemplate, or NULL if none
777 * 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): the #GstPad, or NULL if one could not be found
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: a #GstPad, or %NULL if one could not be found or created.
897 gst_element_request_compatible_pad (GstElement * element,
898 GstPadTemplate * templ)
900 GstPadTemplate *templ_new;
903 g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
904 g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
906 /* FIXME: should really loop through the templates, testing each for
907 * compatibility and pad availability. */
908 templ_new = gst_element_get_compatible_pad_template (element, templ);
910 pad = gst_element_get_pad_from_template (element, templ_new);
912 /* This can happen for non-request pads. No need to unref. */
913 if (pad && GST_PAD_PEER (pad))
920 * Checks if the source pad and the sink pad can be linked.
921 * Both @srcpad and @sinkpad must be unlinked and have a parent.
924 gst_pad_check_link (GstPad * srcpad, GstPad * sinkpad)
926 /* FIXME This function is gross. It's almost a direct copy of
927 * gst_pad_link_filtered(). Any decent programmer would attempt
928 * to merge the two functions, which I will do some day. --ds
932 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
933 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
935 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
936 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
938 /* FIXME: shouldn't we convert this to g_return_val_if_fail? */
939 if (GST_PAD_PEER (srcpad) != NULL) {
940 GST_CAT_INFO (GST_CAT_PADS, "Source pad %s:%s has a peer, failed",
941 GST_DEBUG_PAD_NAME (srcpad));
944 if (GST_PAD_PEER (sinkpad) != NULL) {
945 GST_CAT_INFO (GST_CAT_PADS, "Sink pad %s:%s has a peer, failed",
946 GST_DEBUG_PAD_NAME (sinkpad));
949 if (!GST_PAD_IS_SRC (srcpad)) {
950 GST_CAT_INFO (GST_CAT_PADS, "Src pad %s:%s is not source pad, failed",
951 GST_DEBUG_PAD_NAME (srcpad));
954 if (!GST_PAD_IS_SINK (sinkpad)) {
955 GST_CAT_INFO (GST_CAT_PADS, "Sink pad %s:%s is not sink pad, failed",
956 GST_DEBUG_PAD_NAME (sinkpad));
959 if (GST_PAD_PARENT (srcpad) == NULL) {
960 GST_CAT_INFO (GST_CAT_PADS, "Src pad %s:%s has no parent, failed",
961 GST_DEBUG_PAD_NAME (srcpad));
964 if (GST_PAD_PARENT (sinkpad) == NULL) {
965 GST_CAT_INFO (GST_CAT_PADS, "Sink pad %s:%s has no parent, failed",
966 GST_DEBUG_PAD_NAME (srcpad));
974 * gst_element_get_compatible_pad:
975 * @element: (transfer none): a #GstElement in which the pad should be found.
976 * @pad: (transfer none): the #GstPad to find a compatible one for.
977 * @caps: (allow-none): the #GstCaps to use as a filter.
979 * Looks for an unlinked pad to which the given pad can link. It is not
980 * guaranteed that linking the pads will work, though it should work in most
983 * This function will first attempt to find a compatible unlinked ALWAYS pad,
984 * and if none can be found, it will request a compatible REQUEST pad by looking
985 * at the templates of @element.
987 * Returns: (transfer full): the #GstPad to which a link can be made, or %NULL
988 * if one cannot be found. gst_object_unref() after usage.
991 gst_element_get_compatible_pad (GstElement * element, GstPad * pad,
995 GstPadTemplate *templ;
997 GstPad *foundpad = NULL;
999 GValue padptr = { 0, };
1001 g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
1002 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1004 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1005 "finding pad in %s compatible with %s:%s",
1006 GST_ELEMENT_NAME (element), GST_DEBUG_PAD_NAME (pad));
1008 g_return_val_if_fail (GST_PAD_PEER (pad) == NULL, NULL);
1012 /* try to get an existing unlinked pad */
1013 if (GST_PAD_IS_SRC (pad)) {
1014 pads = gst_element_iterate_sink_pads (element);
1015 } else if (GST_PAD_IS_SINK (pad)) {
1016 pads = gst_element_iterate_src_pads (element);
1018 pads = gst_element_iterate_pads (element);
1022 switch (gst_iterator_next (pads, &padptr)) {
1023 case GST_ITERATOR_OK:
1030 current = g_value_get_object (&padptr);
1032 GST_CAT_LOG (GST_CAT_ELEMENT_PADS, "examining pad %s:%s",
1033 GST_DEBUG_PAD_NAME (current));
1035 if (GST_PAD_IS_SRC (current)) {
1042 peer = gst_pad_get_peer (current);
1044 if (peer == NULL && gst_pad_check_link (srcpad, sinkpad)) {
1045 GstCaps *temp, *intersection;
1046 gboolean compatible;
1048 /* Now check if the two pads' caps are compatible */
1049 temp = gst_pad_query_caps (pad, NULL);
1051 intersection = gst_caps_intersect (temp, caps);
1052 gst_caps_unref (temp);
1054 intersection = temp;
1057 temp = gst_pad_query_caps (current, NULL);
1058 compatible = gst_caps_can_intersect (temp, intersection);
1059 gst_caps_unref (temp);
1060 gst_caps_unref (intersection);
1063 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1064 "found existing unlinked compatible pad %s:%s",
1065 GST_DEBUG_PAD_NAME (current));
1066 gst_iterator_free (pads);
1068 current = gst_object_ref (current);
1069 g_value_unset (&padptr);
1073 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "incompatible pads");
1076 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1077 "already linked or cannot be linked (peer = %p)", peer);
1079 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "unreffing pads");
1081 g_value_reset (&padptr);
1083 gst_object_unref (peer);
1086 case GST_ITERATOR_DONE:
1089 case GST_ITERATOR_RESYNC:
1090 gst_iterator_resync (pads);
1092 case GST_ITERATOR_ERROR:
1093 g_assert_not_reached ();
1097 g_value_unset (&padptr);
1098 gst_iterator_free (pads);
1100 GST_CAT_DEBUG_OBJECT (GST_CAT_ELEMENT_PADS, element,
1101 "Could not find a compatible unlinked always pad to link to %s:%s, now checking request pads",
1102 GST_DEBUG_PAD_NAME (pad));
1104 /* try to create a new one */
1105 /* requesting is a little crazy, we need a template. Let's create one */
1106 /* FIXME: why not gst_pad_get_pad_template (pad); */
1107 templcaps = gst_pad_query_caps (pad, NULL);
1108 templ = gst_pad_template_new ((gchar *) GST_PAD_NAME (pad),
1109 GST_PAD_DIRECTION (pad), GST_PAD_ALWAYS, templcaps);
1110 gst_caps_unref (templcaps);
1112 foundpad = gst_element_request_compatible_pad (element, templ);
1113 gst_object_unref (templ);
1116 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1117 "found existing request pad %s:%s", GST_DEBUG_PAD_NAME (foundpad));
1121 GST_CAT_INFO_OBJECT (GST_CAT_ELEMENT_PADS, element,
1122 "Could not find a compatible pad to link to %s:%s",
1123 GST_DEBUG_PAD_NAME (pad));
1128 * gst_element_state_get_name:
1129 * @state: a #GstState to get the name of.
1131 * Gets a string representing the given state.
1133 * Returns: (transfer none): a string with the name of the state.
1136 gst_element_state_get_name (GstState state)
1139 case GST_STATE_VOID_PENDING:
1140 return "VOID_PENDING";
1141 case GST_STATE_NULL:
1143 case GST_STATE_READY:
1145 case GST_STATE_PLAYING:
1147 case GST_STATE_PAUSED:
1150 /* This is a memory leak */
1151 return g_strdup_printf ("UNKNOWN!(%d)", state);
1156 * gst_element_state_change_return_get_name:
1157 * @state_ret: a #GstStateChangeReturn to get the name of.
1159 * Gets a string representing the given state change result.
1161 * Returns: (transfer none): a string with the name of the state
1165 gst_element_state_change_return_get_name (GstStateChangeReturn state_ret)
1167 switch (state_ret) {
1168 case GST_STATE_CHANGE_FAILURE:
1170 case GST_STATE_CHANGE_SUCCESS:
1172 case GST_STATE_CHANGE_ASYNC:
1174 case GST_STATE_CHANGE_NO_PREROLL:
1175 return "NO PREROLL";
1177 /* This is a memory leak */
1178 return g_strdup_printf ("UNKNOWN!(%d)", state_ret);
1184 gst_element_factory_can_accept_all_caps_in_direction (GstElementFactory *
1185 factory, const GstCaps * caps, GstPadDirection direction)
1189 g_return_val_if_fail (factory != NULL, FALSE);
1190 g_return_val_if_fail (caps != NULL, FALSE);
1192 templates = factory->staticpadtemplates;
1195 GstStaticPadTemplate *template = (GstStaticPadTemplate *) templates->data;
1197 if (template->direction == direction) {
1198 GstCaps *templcaps = gst_static_caps_get (&template->static_caps);
1200 if (gst_caps_is_always_compatible (caps, templcaps)) {
1201 gst_caps_unref (templcaps);
1204 gst_caps_unref (templcaps);
1206 templates = g_list_next (templates);
1213 gst_element_factory_can_accept_any_caps_in_direction (GstElementFactory *
1214 factory, const GstCaps * caps, GstPadDirection direction)
1218 g_return_val_if_fail (factory != NULL, FALSE);
1219 g_return_val_if_fail (caps != NULL, FALSE);
1221 templates = factory->staticpadtemplates;
1224 GstStaticPadTemplate *template = (GstStaticPadTemplate *) templates->data;
1226 if (template->direction == direction) {
1227 GstCaps *templcaps = gst_static_caps_get (&template->static_caps);
1229 if (gst_caps_can_intersect (caps, templcaps)) {
1230 gst_caps_unref (templcaps);
1233 gst_caps_unref (templcaps);
1235 templates = g_list_next (templates);
1242 * gst_element_factory_can_sink_all_caps:
1243 * @factory: factory to query
1244 * @caps: the caps to check
1246 * Checks if the factory can sink all possible capabilities.
1248 * Returns: %TRUE if the caps are fully compatible.
1251 gst_element_factory_can_sink_all_caps (GstElementFactory * factory,
1252 const GstCaps * caps)
1254 return gst_element_factory_can_accept_all_caps_in_direction (factory, caps,
1259 * gst_element_factory_can_src_all_caps:
1260 * @factory: factory to query
1261 * @caps: the caps to check
1263 * Checks if the factory can src all possible capabilities.
1265 * Returns: %TRUE if the caps are fully compatible.
1268 gst_element_factory_can_src_all_caps (GstElementFactory * factory,
1269 const GstCaps * caps)
1271 return gst_element_factory_can_accept_all_caps_in_direction (factory, caps,
1276 * gst_element_factory_can_sink_any_caps:
1277 * @factory: factory to query
1278 * @caps: the caps to check
1280 * Checks if the factory can sink any possible capability.
1282 * Returns: %TRUE if the caps have a common subset.
1285 gst_element_factory_can_sink_any_caps (GstElementFactory * factory,
1286 const GstCaps * caps)
1288 return gst_element_factory_can_accept_any_caps_in_direction (factory, caps,
1293 * gst_element_factory_can_src_any_caps:
1294 * @factory: factory to query
1295 * @caps: the caps to check
1297 * Checks if the factory can src any possible capability.
1299 * Returns: %TRUE if the caps have a common subset.
1302 gst_element_factory_can_src_any_caps (GstElementFactory * factory,
1303 const GstCaps * caps)
1305 return gst_element_factory_can_accept_any_caps_in_direction (factory, caps,
1309 /* if return val is true, *direct_child is a caller-owned ref on the direct
1310 * child of ancestor that is part of object's ancestry */
1312 object_has_ancestor (GstObject * object, GstObject * ancestor,
1313 GstObject ** direct_child)
1315 GstObject *child, *parent;
1318 *direct_child = NULL;
1320 child = gst_object_ref (object);
1321 parent = gst_object_get_parent (object);
1324 if (ancestor == parent) {
1326 *direct_child = child;
1328 gst_object_unref (child);
1329 gst_object_unref (parent);
1333 gst_object_unref (child);
1335 parent = gst_object_get_parent (parent);
1338 gst_object_unref (child);
1343 /* caller owns return */
1345 find_common_root (GstObject * o1, GstObject * o2)
1347 GstObject *top = o1;
1348 GstObject *kid1, *kid2;
1349 GstObject *root = NULL;
1351 while (GST_OBJECT_PARENT (top))
1352 top = GST_OBJECT_PARENT (top);
1354 /* the itsy-bitsy spider... */
1356 if (!object_has_ancestor (o2, top, &kid2))
1359 root = gst_object_ref (top);
1361 if (!object_has_ancestor (o1, kid2, &kid1)) {
1362 gst_object_unref (kid2);
1366 if (!object_has_ancestor (o2, kid1, &kid2)) {
1367 gst_object_unref (kid1);
1374 /* caller does not own return */
1376 ghost_up (GstElement * e, GstPad * pad)
1378 static gint ghost_pad_index = 0;
1383 GstObject *parent = GST_OBJECT_PARENT (e);
1385 name = g_strdup_printf ("ghost%d", ghost_pad_index++);
1386 gpad = gst_ghost_pad_new (name, pad);
1390 gst_element_get_state (e, ¤t, &next, 0);
1392 if (current > GST_STATE_READY || next == GST_STATE_PAUSED)
1393 gst_pad_set_active (gpad, TRUE);
1395 if (!gst_element_add_pad ((GstElement *) parent, gpad)) {
1396 g_warning ("Pad named %s already exists in element %s\n",
1397 GST_OBJECT_NAME (gpad), GST_OBJECT_NAME (parent));
1398 gst_object_unref ((GstObject *) gpad);
1399 GST_STATE_UNLOCK (e);
1402 GST_STATE_UNLOCK (e);
1408 remove_pad (gpointer ppad, gpointer unused)
1412 if (!gst_element_remove_pad ((GstElement *) GST_OBJECT_PARENT (pad), pad))
1413 g_warning ("Couldn't remove pad %s from element %s",
1414 GST_OBJECT_NAME (pad), GST_OBJECT_NAME (GST_OBJECT_PARENT (pad)));
1418 prepare_link_maybe_ghosting (GstPad ** src, GstPad ** sink,
1419 GSList ** pads_created)
1423 GSList *pads_created_local = NULL;
1425 g_assert (pads_created);
1427 e1 = GST_OBJECT_PARENT (*src);
1428 e2 = GST_OBJECT_PARENT (*sink);
1430 if (G_UNLIKELY (e1 == NULL)) {
1431 GST_WARNING ("Trying to ghost a pad that doesn't have a parent: %"
1432 GST_PTR_FORMAT, *src);
1435 if (G_UNLIKELY (e2 == NULL)) {
1436 GST_WARNING ("Trying to ghost a pad that doesn't have a parent: %"
1437 GST_PTR_FORMAT, *sink);
1441 if (GST_OBJECT_PARENT (e1) == GST_OBJECT_PARENT (e2)) {
1442 GST_CAT_INFO (GST_CAT_PADS, "%s and %s in same bin, no need for ghost pads",
1443 GST_OBJECT_NAME (e1), GST_OBJECT_NAME (e2));
1447 GST_CAT_INFO (GST_CAT_PADS, "%s and %s not in same bin, making ghost pads",
1448 GST_OBJECT_NAME (e1), GST_OBJECT_NAME (e2));
1450 /* we need to setup some ghost pads */
1451 root = find_common_root (e1, e2);
1453 g_warning ("Trying to connect elements that don't share a common "
1454 "ancestor: %s and %s", GST_ELEMENT_NAME (e1), GST_ELEMENT_NAME (e2));
1458 while (GST_OBJECT_PARENT (e1) != root) {
1459 *src = ghost_up ((GstElement *) e1, *src);
1462 e1 = GST_OBJECT_PARENT (*src);
1463 pads_created_local = g_slist_prepend (pads_created_local, *src);
1465 while (GST_OBJECT_PARENT (e2) != root) {
1466 *sink = ghost_up ((GstElement *) e2, *sink);
1469 e2 = GST_OBJECT_PARENT (*sink);
1470 pads_created_local = g_slist_prepend (pads_created_local, *sink);
1473 gst_object_unref (root);
1474 *pads_created = g_slist_concat (*pads_created, pads_created_local);
1478 gst_object_unref (root);
1479 g_slist_foreach (pads_created_local, remove_pad, NULL);
1480 g_slist_free (pads_created_local);
1485 pad_link_maybe_ghosting (GstPad * src, GstPad * sink, GstPadLinkCheck flags)
1487 GSList *pads_created = NULL;
1490 if (!prepare_link_maybe_ghosting (&src, &sink, &pads_created)) {
1493 ret = (gst_pad_link_full (src, sink, flags) == GST_PAD_LINK_OK);
1497 g_slist_foreach (pads_created, remove_pad, NULL);
1499 g_slist_free (pads_created);
1505 * gst_element_link_pads_full:
1506 * @src: a #GstElement containing the source pad.
1507 * @srcpadname: (allow-none): the name of the #GstPad in source element
1508 * or NULL for any pad.
1509 * @dest: (transfer none): the #GstElement containing the destination pad.
1510 * @destpadname: (allow-none): the name of the #GstPad in destination element,
1511 * or NULL for any pad.
1512 * @flags: the #GstPadLinkCheck to be performed when linking pads.
1514 * Links the two named pads of the source and destination elements.
1515 * Side effect is that if one of the pads has no parent, it becomes a
1516 * child of the parent of the other element. If they have different
1517 * parents, the link fails.
1519 * Calling gst_element_link_pads_full() with @flags == %GST_PAD_LINK_CHECK_DEFAULT
1520 * is the same as calling gst_element_link_pads() and the recommended way of
1521 * linking pads with safety checks applied.
1523 * This is a convenience function for gst_pad_link_full().
1525 * Returns: TRUE if the pads could be linked, FALSE otherwise.
1528 gst_element_link_pads_full (GstElement * src, const gchar * srcpadname,
1529 GstElement * dest, const gchar * destpadname, GstPadLinkCheck flags)
1531 const GList *srcpads, *destpads, *srctempls, *desttempls, *l;
1532 GstPad *srcpad, *destpad;
1533 GstPadTemplate *srctempl, *desttempl;
1534 GstElementClass *srcclass, *destclass;
1537 g_return_val_if_fail (GST_IS_ELEMENT (src), FALSE);
1538 g_return_val_if_fail (GST_IS_ELEMENT (dest), FALSE);
1540 GST_CAT_INFO (GST_CAT_ELEMENT_PADS,
1541 "trying to link element %s:%s to element %s:%s", GST_ELEMENT_NAME (src),
1542 srcpadname ? srcpadname : "(any)", GST_ELEMENT_NAME (dest),
1543 destpadname ? destpadname : "(any)");
1547 /* name specified, look it up */
1548 if (!(srcpad = gst_element_get_static_pad (src, srcpadname)))
1549 srcpad = gst_element_get_request_pad (src, srcpadname);
1551 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no pad %s:%s",
1552 GST_ELEMENT_NAME (src), srcpadname);
1555 if (!(GST_PAD_DIRECTION (srcpad) == GST_PAD_SRC)) {
1556 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is no src pad",
1557 GST_DEBUG_PAD_NAME (srcpad));
1558 gst_object_unref (srcpad);
1561 if (GST_PAD_PEER (srcpad) != NULL) {
1562 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1563 "pad %s:%s is already linked to %s:%s", GST_DEBUG_PAD_NAME (srcpad),
1564 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
1565 gst_object_unref (srcpad);
1571 /* no name given, get the first available pad */
1572 GST_OBJECT_LOCK (src);
1573 srcpads = GST_ELEMENT_PADS (src);
1574 srcpad = srcpads ? GST_PAD_CAST (srcpads->data) : NULL;
1576 gst_object_ref (srcpad);
1577 GST_OBJECT_UNLOCK (src);
1580 /* get a destination pad */
1582 /* name specified, look it up */
1583 if (!(destpad = gst_element_get_static_pad (dest, destpadname)))
1584 destpad = gst_element_get_request_pad (dest, destpadname);
1586 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no pad %s:%s",
1587 GST_ELEMENT_NAME (dest), destpadname);
1590 if (!(GST_PAD_DIRECTION (destpad) == GST_PAD_SINK)) {
1591 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is no sink pad",
1592 GST_DEBUG_PAD_NAME (destpad));
1593 gst_object_unref (destpad);
1596 if (GST_PAD_PEER (destpad) != NULL) {
1597 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1598 "pad %s:%s is already linked to %s:%s",
1599 GST_DEBUG_PAD_NAME (destpad),
1600 GST_DEBUG_PAD_NAME (GST_PAD_PEER (destpad)));
1601 gst_object_unref (destpad);
1607 /* no name given, get the first available pad */
1608 GST_OBJECT_LOCK (dest);
1609 destpads = GST_ELEMENT_PADS (dest);
1610 destpad = destpads ? GST_PAD_CAST (destpads->data) : NULL;
1612 gst_object_ref (destpad);
1613 GST_OBJECT_UNLOCK (dest);
1616 if (srcpadname && destpadname) {
1619 /* two explicitly specified pads */
1620 result = pad_link_maybe_ghosting (srcpad, destpad, flags);
1622 gst_object_unref (srcpad);
1623 gst_object_unref (destpad);
1629 /* loop through the allowed pads in the source, trying to find a
1630 * compatible destination pad */
1631 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1632 "looping through allowed src and dest pads");
1634 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "trying src pad %s:%s",
1635 GST_DEBUG_PAD_NAME (srcpad));
1636 if ((GST_PAD_DIRECTION (srcpad) == GST_PAD_SRC) &&
1637 (GST_PAD_PEER (srcpad) == NULL)) {
1642 gst_object_ref (temp);
1644 temp = gst_element_get_compatible_pad (dest, srcpad, NULL);
1647 if (temp && pad_link_maybe_ghosting (srcpad, temp, flags)) {
1648 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "linked pad %s:%s to pad %s:%s",
1649 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (temp));
1651 gst_object_unref (destpad);
1652 gst_object_unref (srcpad);
1653 gst_object_unref (temp);
1658 gst_object_unref (temp);
1661 /* find a better way for this mess */
1663 srcpads = g_list_next (srcpads);
1665 gst_object_unref (srcpad);
1666 srcpad = GST_PAD_CAST (srcpads->data);
1667 gst_object_ref (srcpad);
1673 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s:%s to %s",
1674 GST_DEBUG_PAD_NAME (srcpad), GST_ELEMENT_NAME (dest));
1676 gst_object_unref (destpad);
1680 gst_object_unref (srcpad);
1684 /* loop through the existing pads in the destination */
1686 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "trying dest pad %s:%s",
1687 GST_DEBUG_PAD_NAME (destpad));
1688 if ((GST_PAD_DIRECTION (destpad) == GST_PAD_SINK) &&
1689 (GST_PAD_PEER (destpad) == NULL)) {
1690 GstPad *temp = gst_element_get_compatible_pad (src, destpad, NULL);
1692 if (temp && pad_link_maybe_ghosting (temp, destpad, flags)) {
1693 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "linked pad %s:%s to pad %s:%s",
1694 GST_DEBUG_PAD_NAME (temp), GST_DEBUG_PAD_NAME (destpad));
1695 gst_object_unref (temp);
1696 gst_object_unref (destpad);
1700 gst_object_unref (temp);
1704 destpads = g_list_next (destpads);
1706 gst_object_unref (destpad);
1707 destpad = GST_PAD_CAST (destpads->data);
1708 gst_object_ref (destpad);
1715 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s to %s:%s",
1716 GST_ELEMENT_NAME (src), GST_DEBUG_PAD_NAME (destpad));
1717 gst_object_unref (destpad);
1721 gst_object_unref (destpad);
1725 srcclass = GST_ELEMENT_GET_CLASS (src);
1726 destclass = GST_ELEMENT_GET_CLASS (dest);
1728 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1729 "we might have request pads on both sides, checking...");
1730 srctempls = gst_element_class_get_pad_template_list (srcclass);
1731 desttempls = gst_element_class_get_pad_template_list (destclass);
1733 if (srctempls && desttempls) {
1735 srctempl = (GstPadTemplate *) srctempls->data;
1736 if (srctempl->presence == GST_PAD_REQUEST) {
1737 for (l = desttempls; l; l = l->next) {
1738 desttempl = (GstPadTemplate *) l->data;
1739 if (desttempl->presence == GST_PAD_REQUEST &&
1740 desttempl->direction != srctempl->direction) {
1741 GstCaps *srccaps, *destcaps;
1743 srccaps = gst_pad_template_get_caps (srctempl);
1744 destcaps = gst_pad_template_get_caps (desttempl);
1745 if (gst_caps_is_always_compatible (srccaps, destcaps)) {
1747 gst_element_request_pad (src, srctempl,
1748 srctempl->name_template, NULL);
1750 gst_element_request_pad (dest, desttempl,
1751 desttempl->name_template, NULL);
1752 if (srcpad && destpad
1753 && pad_link_maybe_ghosting (srcpad, destpad, flags)) {
1754 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
1755 "linked pad %s:%s to pad %s:%s",
1756 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (destpad));
1757 gst_object_unref (srcpad);
1758 gst_object_unref (destpad);
1759 gst_caps_unref (srccaps);
1760 gst_caps_unref (destcaps);
1763 /* it failed, so we release the request pads */
1765 gst_element_release_request_pad (src, srcpad);
1767 gst_element_release_request_pad (dest, destpad);
1769 gst_caps_unref (srccaps);
1770 gst_caps_unref (destcaps);
1774 srctempls = srctempls->next;
1778 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s to %s",
1779 GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (dest));
1784 * gst_element_link_pads:
1785 * @src: a #GstElement containing the source pad.
1786 * @srcpadname: (allow-none): the name of the #GstPad in source element
1787 * or NULL for any pad.
1788 * @dest: (transfer none): the #GstElement containing the destination pad.
1789 * @destpadname: (allow-none): the name of the #GstPad in destination element,
1790 * or NULL for any pad.
1792 * Links the two named pads of the source and destination elements.
1793 * Side effect is that if one of the pads has no parent, it becomes a
1794 * child of the parent of the other element. If they have different
1795 * parents, the link fails.
1797 * Returns: TRUE if the pads could be linked, FALSE otherwise.
1800 gst_element_link_pads (GstElement * src, const gchar * srcpadname,
1801 GstElement * dest, const gchar * destpadname)
1803 return gst_element_link_pads_full (src, srcpadname, dest, destpadname,
1804 GST_PAD_LINK_CHECK_DEFAULT);
1808 * gst_element_link_pads_filtered:
1809 * @src: a #GstElement containing the source pad.
1810 * @srcpadname: (allow-none): the name of the #GstPad in source element
1811 * or NULL for any pad.
1812 * @dest: (transfer none): the #GstElement containing the destination pad.
1813 * @destpadname: (allow-none): the name of the #GstPad in destination element
1814 * or NULL for any pad.
1815 * @filter: (transfer none) (allow-none): the #GstCaps to filter the link,
1816 * or #NULL for no filter.
1818 * Links the two named pads of the source and destination elements. Side effect
1819 * is that if one of the pads has no parent, it becomes a child of the parent of
1820 * the other element. If they have different parents, the link fails. If @caps
1821 * is not #NULL, makes sure that the caps of the link is a subset of @caps.
1823 * Returns: TRUE if the pads could be linked, FALSE otherwise.
1826 gst_element_link_pads_filtered (GstElement * src, const gchar * srcpadname,
1827 GstElement * dest, const gchar * destpadname, GstCaps * filter)
1830 g_return_val_if_fail (GST_IS_ELEMENT (src), FALSE);
1831 g_return_val_if_fail (GST_IS_ELEMENT (dest), FALSE);
1832 g_return_val_if_fail (filter == NULL || GST_IS_CAPS (filter), FALSE);
1835 GstElement *capsfilter;
1837 GstState state, pending;
1840 capsfilter = gst_element_factory_make ("capsfilter", NULL);
1842 GST_ERROR ("Could not make a capsfilter");
1846 parent = gst_object_get_parent (GST_OBJECT (src));
1847 g_return_val_if_fail (GST_IS_BIN (parent), FALSE);
1849 gst_element_get_state (GST_ELEMENT_CAST (parent), &state, &pending, 0);
1851 if (!gst_bin_add (GST_BIN (parent), capsfilter)) {
1852 GST_ERROR ("Could not add capsfilter");
1853 gst_object_unref (capsfilter);
1854 gst_object_unref (parent);
1858 if (pending != GST_STATE_VOID_PENDING)
1861 gst_element_set_state (capsfilter, state);
1863 gst_object_unref (parent);
1865 g_object_set (capsfilter, "caps", filter, NULL);
1867 lr1 = gst_element_link_pads (src, srcpadname, capsfilter, "sink");
1868 lr2 = gst_element_link_pads (capsfilter, "src", dest, destpadname);
1873 GST_INFO ("Could not link pads: %s:%s - capsfilter:sink",
1874 GST_ELEMENT_NAME (src), srcpadname);
1876 GST_INFO ("Could not link pads: capsfilter:src - %s:%s",
1877 GST_ELEMENT_NAME (dest), destpadname);
1879 gst_element_set_state (capsfilter, GST_STATE_NULL);
1880 /* this will unlink and unref as appropriate */
1881 gst_bin_remove (GST_BIN (GST_OBJECT_PARENT (capsfilter)), capsfilter);
1885 if (gst_element_link_pads (src, srcpadname, dest, destpadname)) {
1888 GST_INFO ("Could not link pads: %s:%s - %s:%s", GST_ELEMENT_NAME (src),
1889 srcpadname, GST_ELEMENT_NAME (dest), destpadname);
1897 * @src: (transfer none): a #GstElement containing the source pad.
1898 * @dest: (transfer none): the #GstElement containing the destination pad.
1900 * Links @src to @dest. The link must be from source to
1901 * destination; the other direction will not be tried. The function looks for
1902 * existing pads that aren't linked yet. It will request new pads if necessary.
1903 * Such pads need to be released manually when unlinking.
1904 * If multiple links are possible, only one is established.
1906 * Make sure you have added your elements to a bin or pipeline with
1907 * gst_bin_add() before trying to link them.
1909 * Returns: TRUE if the elements could be linked, FALSE otherwise.
1912 gst_element_link (GstElement * src, GstElement * dest)
1914 return gst_element_link_pads (src, NULL, dest, NULL);
1918 * gst_element_link_many:
1919 * @element_1: (transfer none): the first #GstElement in the link chain.
1920 * @element_2: (transfer none): the second #GstElement in the link chain.
1921 * @...: the NULL-terminated list of elements to link in order.
1923 * Chain together a series of elements. Uses gst_element_link().
1924 * Make sure you have added your elements to a bin or pipeline with
1925 * gst_bin_add() before trying to link them.
1927 * Returns: TRUE on success, FALSE otherwise.
1930 gst_element_link_many (GstElement * element_1, GstElement * element_2, ...)
1932 gboolean res = TRUE;
1935 g_return_val_if_fail (GST_IS_ELEMENT (element_1), FALSE);
1936 g_return_val_if_fail (GST_IS_ELEMENT (element_2), FALSE);
1938 va_start (args, element_2);
1941 if (!gst_element_link (element_1, element_2)) {
1946 element_1 = element_2;
1947 element_2 = va_arg (args, GstElement *);
1956 * gst_element_link_filtered:
1957 * @src: a #GstElement containing the source pad.
1958 * @dest: (transfer none): the #GstElement containing the destination pad.
1959 * @filter: (transfer none) (allow-none): the #GstCaps to filter the link,
1960 * or #NULL for no filter.
1962 * Links @src to @dest using the given caps as filtercaps.
1963 * The link must be from source to
1964 * destination; the other direction will not be tried. The function looks for
1965 * existing pads that aren't linked yet. It will request new pads if necessary.
1966 * If multiple links are possible, only one is established.
1968 * Make sure you have added your elements to a bin or pipeline with
1969 * gst_bin_add() before trying to link them.
1971 * Returns: TRUE if the pads could be linked, FALSE otherwise.
1974 gst_element_link_filtered (GstElement * src, GstElement * dest,
1977 return gst_element_link_pads_filtered (src, NULL, dest, NULL, filter);
1981 * gst_element_unlink_pads:
1982 * @src: a (transfer none): #GstElement containing the source pad.
1983 * @srcpadname: the name of the #GstPad in source element.
1984 * @dest: (transfer none): a #GstElement containing the destination pad.
1985 * @destpadname: the name of the #GstPad in destination element.
1987 * Unlinks the two named pads of the source and destination elements.
1989 * This is a convenience function for gst_pad_unlink().
1992 gst_element_unlink_pads (GstElement * src, const gchar * srcpadname,
1993 GstElement * dest, const gchar * destpadname)
1995 GstPad *srcpad, *destpad;
1996 gboolean srcrequest, destrequest;
1998 srcrequest = destrequest = FALSE;
2000 g_return_if_fail (src != NULL);
2001 g_return_if_fail (GST_IS_ELEMENT (src));
2002 g_return_if_fail (srcpadname != NULL);
2003 g_return_if_fail (dest != NULL);
2004 g_return_if_fail (GST_IS_ELEMENT (dest));
2005 g_return_if_fail (destpadname != NULL);
2007 /* obtain the pads requested */
2008 if (!(srcpad = gst_element_get_static_pad (src, srcpadname)))
2009 if ((srcpad = gst_element_get_request_pad (src, srcpadname)))
2011 if (srcpad == NULL) {
2012 GST_WARNING_OBJECT (src, "source element has no pad \"%s\"", srcpadname);
2015 if (!(destpad = gst_element_get_static_pad (dest, destpadname)))
2016 if ((destpad = gst_element_get_request_pad (dest, destpadname)))
2018 if (destpad == NULL) {
2019 GST_WARNING_OBJECT (dest, "destination element has no pad \"%s\"",
2024 /* we're satisfied they can be unlinked, let's do it */
2025 gst_pad_unlink (srcpad, destpad);
2028 gst_element_release_request_pad (dest, destpad);
2029 gst_object_unref (destpad);
2033 gst_element_release_request_pad (src, srcpad);
2034 gst_object_unref (srcpad);
2038 * gst_element_unlink_many:
2039 * @element_1: (transfer none): the first #GstElement in the link chain.
2040 * @element_2: (transfer none): the second #GstElement in the link chain.
2041 * @...: the NULL-terminated list of elements to unlink in order.
2043 * Unlinks a series of elements. Uses gst_element_unlink().
2046 gst_element_unlink_many (GstElement * element_1, GstElement * element_2, ...)
2050 g_return_if_fail (element_1 != NULL && element_2 != NULL);
2051 g_return_if_fail (GST_IS_ELEMENT (element_1) && GST_IS_ELEMENT (element_2));
2053 va_start (args, element_2);
2056 gst_element_unlink (element_1, element_2);
2058 element_1 = element_2;
2059 element_2 = va_arg (args, GstElement *);
2066 * gst_element_unlink:
2067 * @src: (transfer none): the source #GstElement to unlink.
2068 * @dest: (transfer none): the sink #GstElement to unlink.
2070 * Unlinks all source pads of the source element with all sink pads
2071 * of the sink element to which they are linked.
2073 * If the link has been made using gst_element_link(), it could have created an
2074 * requestpad, which has to be released using gst_element_release_request_pad().
2077 gst_element_unlink (GstElement * src, GstElement * dest)
2080 gboolean done = FALSE;
2081 GValue data = { 0, };
2083 g_return_if_fail (GST_IS_ELEMENT (src));
2084 g_return_if_fail (GST_IS_ELEMENT (dest));
2086 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "unlinking \"%s\" and \"%s\"",
2087 GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (dest));
2089 pads = gst_element_iterate_pads (src);
2091 switch (gst_iterator_next (pads, &data)) {
2092 case GST_ITERATOR_OK:
2094 GstPad *pad = g_value_get_object (&data);
2096 if (GST_PAD_IS_SRC (pad)) {
2097 GstPad *peerpad = gst_pad_get_peer (pad);
2099 /* see if the pad is linked and is really a pad of dest */
2101 GstElement *peerelem;
2103 peerelem = gst_pad_get_parent_element (peerpad);
2105 if (peerelem == dest) {
2106 gst_pad_unlink (pad, peerpad);
2109 gst_object_unref (peerelem);
2111 gst_object_unref (peerpad);
2114 g_value_reset (&data);
2117 case GST_ITERATOR_RESYNC:
2118 gst_iterator_resync (pads);
2120 case GST_ITERATOR_DONE:
2124 g_assert_not_reached ();
2128 g_value_unset (&data);
2129 gst_iterator_free (pads);
2133 * gst_element_query_position:
2134 * @element: a #GstElement to invoke the position query on.
2135 * @format: the #GstFormat requested
2136 * @cur: (out) (allow-none): a location in which to store the current
2137 * position, or NULL.
2139 * Queries an element for the stream position. If one repeatedly calls this
2140 * function one can also create and reuse it in gst_element_query().
2142 * Returns: TRUE if the query could be performed.
2145 gst_element_query_position (GstElement * element, GstFormat format,
2151 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
2152 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2154 query = gst_query_new_position (format);
2155 ret = gst_element_query (element, query);
2158 gst_query_parse_position (query, NULL, cur);
2160 gst_query_unref (query);
2166 * gst_element_query_duration:
2167 * @element: a #GstElement to invoke the duration query on.
2168 * @format: the #GstFormat requested
2169 * @duration: (out): A location in which to store the total duration, or NULL.
2171 * Queries an element for the total stream duration.
2173 * Returns: TRUE if the query could be performed.
2176 gst_element_query_duration (GstElement * element, GstFormat format,
2182 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
2183 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2185 query = gst_query_new_duration (format);
2186 ret = gst_element_query (element, query);
2189 gst_query_parse_duration (query, NULL, duration);
2191 gst_query_unref (query);
2197 * gst_element_query_convert:
2198 * @element: a #GstElement to invoke the convert query on.
2199 * @src_format: (inout): a #GstFormat to convert from.
2200 * @src_val: a value to convert.
2201 * @dest_format: the #GstFormat to convert to.
2202 * @dest_val: (out): a pointer to the result.
2204 * Queries an element to convert @src_val in @src_format to @dest_format.
2206 * Returns: TRUE if the query could be performed.
2209 gst_element_query_convert (GstElement * element, GstFormat src_format,
2210 gint64 src_val, GstFormat dest_format, gint64 * dest_val)
2215 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
2216 g_return_val_if_fail (dest_format != GST_FORMAT_UNDEFINED, FALSE);
2217 g_return_val_if_fail (dest_val != NULL, FALSE);
2219 if (dest_format == src_format || src_val == -1) {
2220 *dest_val = src_val;
2224 query = gst_query_new_convert (src_format, src_val, dest_format);
2225 ret = gst_element_query (element, query);
2228 gst_query_parse_convert (query, NULL, NULL, NULL, dest_val);
2230 gst_query_unref (query);
2236 * gst_element_seek_simple:
2237 * @element: a #GstElement to seek on
2238 * @format: a #GstFormat to execute the seek in, such as #GST_FORMAT_TIME
2239 * @seek_flags: seek options; playback applications will usually want to use
2240 * GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_KEY_UNIT here
2241 * @seek_pos: position to seek to (relative to the start); if you are doing
2242 * a seek in #GST_FORMAT_TIME this value is in nanoseconds -
2243 * multiply with #GST_SECOND to convert seconds to nanoseconds or
2244 * with #GST_MSECOND to convert milliseconds to nanoseconds.
2246 * Simple API to perform a seek on the given element, meaning it just seeks
2247 * to the given position relative to the start of the stream. For more complex
2248 * operations like segment seeks (e.g. for looping) or changing the playback
2249 * rate or seeking relative to the last configured playback segment you should
2250 * use gst_element_seek().
2252 * In a completely prerolled PAUSED or PLAYING pipeline, seeking is always
2253 * guaranteed to return %TRUE on a seekable media type or %FALSE when the media
2254 * type is certainly not seekable (such as a live stream).
2256 * Some elements allow for seeking in the READY state, in this
2257 * case they will store the seek event and execute it when they are put to
2258 * PAUSED. If the element supports seek in READY, it will always return %TRUE when
2259 * it receives the event in the READY state.
2261 * Returns: %TRUE if the seek operation succeeded. Flushing seeks will trigger a
2262 * preroll, which will emit %GST_MESSAGE_ASYNC_DONE.
2265 gst_element_seek_simple (GstElement * element, GstFormat format,
2266 GstSeekFlags seek_flags, gint64 seek_pos)
2268 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
2269 g_return_val_if_fail (seek_pos >= 0, FALSE);
2271 return gst_element_seek (element, 1.0, format, seek_flags,
2272 GST_SEEK_TYPE_SET, seek_pos, GST_SEEK_TYPE_NONE, 0);
2276 * gst_pad_use_fixed_caps:
2277 * @pad: the pad to use
2279 * A helper function you can use that sets the FIXED_CAPS flag
2280 * This way the default CAPS query will always return the negotiated caps
2281 * or in case the pad is not negotiated, the padtemplate caps.
2283 * The negotiated caps are the caps of the last CAPS event that passed on the
2284 * pad. Use this function on a pad that, once it negotiated to a CAPS, cannot
2285 * be renegotiated to something else.
2288 gst_pad_use_fixed_caps (GstPad * pad)
2290 GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_FIXED_CAPS);
2294 * gst_pad_get_parent_element:
2297 * Gets the parent of @pad, cast to a #GstElement. If a @pad has no parent or
2298 * its parent is not an element, return NULL.
2300 * Returns: (transfer full): the parent of the pad. The caller has a
2301 * reference on the parent, so unref when you're finished with it.
2306 gst_pad_get_parent_element (GstPad * pad)
2310 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2312 p = gst_object_get_parent (GST_OBJECT_CAST (pad));
2314 if (p && !GST_IS_ELEMENT (p)) {
2315 gst_object_unref (p);
2318 return GST_ELEMENT_CAST (p);
2322 * gst_object_default_error:
2323 * @source: the #GstObject that initiated the error.
2324 * @error: (in): the GError.
2325 * @debug: (in) (allow-none): an additional debug information string, or NULL
2327 * A default error function that uses g_printerr() to display the error message
2328 * and the optional debug sting..
2330 * The default handler will simply print the error string using g_print.
2333 gst_object_default_error (GstObject * source, const GError * error,
2334 const gchar * debug)
2336 gchar *name = gst_object_get_path_string (source);
2338 g_printerr (_("ERROR: from element %s: %s\n"), name, error->message);
2340 g_printerr (_("Additional debug info:\n%s\n"), debug);
2348 * @element_1: (transfer full): the #GstElement element to add to the bin
2349 * @...: (transfer full): additional elements to add to the bin
2351 * Adds a NULL-terminated list of elements to a bin. This function is
2352 * equivalent to calling gst_bin_add() for each member of the list. The return
2353 * value of each gst_bin_add() is ignored.
2356 gst_bin_add_many (GstBin * bin, GstElement * element_1, ...)
2360 g_return_if_fail (GST_IS_BIN (bin));
2361 g_return_if_fail (GST_IS_ELEMENT (element_1));
2363 va_start (args, element_1);
2366 gst_bin_add (bin, element_1);
2368 element_1 = va_arg (args, GstElement *);
2375 * gst_bin_remove_many:
2377 * @element_1: (transfer none): the first #GstElement to remove from the bin
2378 * @...: (transfer none): NULL-terminated list of elements to remove from the bin
2380 * Remove a list of elements from a bin. This function is equivalent
2381 * to calling gst_bin_remove() with each member of the list.
2384 gst_bin_remove_many (GstBin * bin, GstElement * element_1, ...)
2388 g_return_if_fail (GST_IS_BIN (bin));
2389 g_return_if_fail (GST_IS_ELEMENT (element_1));
2391 va_start (args, element_1);
2394 gst_bin_remove (bin, element_1);
2396 element_1 = va_arg (args, GstElement *);
2406 } QueryAcceptCapsData;
2409 query_accept_caps_func (GstPad * pad, QueryAcceptCapsData * data)
2411 if (G_LIKELY (gst_pad_peer_query (pad, data->query))) {
2414 gst_query_parse_accept_caps_result (data->query, &result);
2415 data->ret &= result;
2421 * gst_pad_proxy_query_accept_caps:
2422 * @pad: a #GstPad to proxy.
2423 * @query: an ACCEPT_CAPS #GstQuery.
2425 * Calls gst_pad_accept_caps() for all internally linked pads of @pad and
2426 * returns the intersection of the results.
2428 * This function is useful as a default accept caps query function for an element
2429 * that can handle any stream format, but requires caps that are acceptable for
2432 * Returns: TRUE if @query could be executed
2435 gst_pad_proxy_query_accept_caps (GstPad * pad, GstQuery * query)
2437 QueryAcceptCapsData data;
2439 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2440 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2441 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ACCEPT_CAPS, FALSE);
2443 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2444 "proxying accept caps query for %s:%s", GST_DEBUG_PAD_NAME (pad));
2447 /* value to hold the return, by default it holds TRUE */
2450 gst_pad_forward (pad, (GstPadForwardFunction) query_accept_caps_func, &data);
2451 gst_query_set_accept_caps_result (query, data.ret);
2463 query_caps_func (GstPad * pad, QueryCapsData * data)
2465 gboolean empty = FALSE;
2467 if (G_LIKELY (gst_pad_peer_query (pad, data->query))) {
2468 GstCaps *peercaps, *intersection;
2470 gst_query_parse_caps_result (data->query, &peercaps);
2471 GST_DEBUG_OBJECT (pad, "intersect with result %" GST_PTR_FORMAT, peercaps);
2472 intersection = gst_caps_intersect (data->ret, peercaps);
2473 GST_DEBUG_OBJECT (pad, "intersected %" GST_PTR_FORMAT, intersection);
2475 gst_caps_unref (data->ret);
2476 data->ret = intersection;
2478 /* stop when empty */
2479 empty = gst_caps_is_empty (intersection);
2485 * gst_pad_proxy_query_caps:
2486 * @pad: a #GstPad to proxy.
2487 * @query: a CAPS #GstQuery.
2489 * Calls gst_pad_query_caps() for all internally linked pads fof @pad and returns
2490 * the intersection of the results.
2492 * This function is useful as a default caps query function for an element
2493 * that can handle any stream format, but requires all its pads to have
2494 * the same caps. Two such elements are tee and adder.
2496 * Returns: TRUE if @query could be executed
2499 gst_pad_proxy_query_caps (GstPad * pad, GstQuery * query)
2501 GstCaps *filter, *templ, *result;
2504 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2505 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2506 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CAPS, FALSE);
2508 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "proxying caps query for %s:%s",
2509 GST_DEBUG_PAD_NAME (pad));
2513 /* value to hold the return, by default it holds the filter or ANY */
2514 gst_query_parse_caps (query, &filter);
2515 data.ret = filter ? gst_caps_ref (filter) : gst_caps_new_any ();
2517 gst_pad_forward (pad, (GstPadForwardFunction) query_caps_func, &data);
2519 templ = gst_pad_get_pad_template_caps (pad);
2520 result = gst_caps_intersect (data.ret, templ);
2521 gst_caps_unref (data.ret);
2522 gst_caps_unref (templ);
2524 gst_query_set_caps_result (query, result);
2525 gst_caps_unref (result);
2531 * gst_pad_query_position:
2532 * @pad: a #GstPad to invoke the position query on.
2533 * @format: the #GstFormat requested
2534 * @cur: (out): A location in which to store the current position, or NULL.
2536 * Queries a pad for the stream position.
2538 * Returns: TRUE if the query could be performed.
2541 gst_pad_query_position (GstPad * pad, GstFormat format, gint64 * cur)
2546 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2547 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2549 query = gst_query_new_position (format);
2550 if ((ret = gst_pad_query (pad, query)))
2551 gst_query_parse_position (query, NULL, cur);
2552 gst_query_unref (query);
2558 * gst_pad_peer_query_position:
2559 * @pad: a #GstPad on whose peer to invoke the position query on.
2560 * Must be a sink pad.
2561 * @format: the #GstFormat requested
2562 * @cur: (out) (allow-none): a location in which to store the current
2563 * position, or NULL.
2565 * Queries the peer of a given sink pad for the stream position.
2567 * Returns: TRUE if the query could be performed.
2570 gst_pad_peer_query_position (GstPad * pad, GstFormat format, gint64 * cur)
2573 gboolean ret = FALSE;
2575 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2576 g_return_val_if_fail (GST_PAD_IS_SINK (pad), FALSE);
2577 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2579 query = gst_query_new_position (format);
2580 if ((ret = gst_pad_peer_query (pad, query)))
2581 gst_query_parse_position (query, NULL, cur);
2582 gst_query_unref (query);
2588 * gst_pad_query_duration:
2589 * @pad: a #GstPad to invoke the duration query on.
2590 * @format: the #GstFormat requested
2591 * @duration: (out) (allow-none): a location in which to store the total
2592 * duration, or NULL.
2594 * Queries a pad for the total stream duration.
2596 * Returns: TRUE if the query could be performed.
2599 gst_pad_query_duration (GstPad * pad, GstFormat format, gint64 * duration)
2604 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2605 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2607 query = gst_query_new_duration (format);
2608 if ((ret = gst_pad_query (pad, query)))
2609 gst_query_parse_duration (query, NULL, duration);
2610 gst_query_unref (query);
2616 * gst_pad_peer_query_duration:
2617 * @pad: a #GstPad on whose peer pad to invoke the duration query on.
2618 * Must be a sink pad.
2619 * @format: the #GstFormat requested
2620 * @duration: (out) (allow-none): a location in which to store the total
2621 * duration, or NULL.
2623 * Queries the peer pad of a given sink pad for the total stream duration.
2625 * Returns: TRUE if the query could be performed.
2628 gst_pad_peer_query_duration (GstPad * pad, GstFormat format, gint64 * duration)
2631 gboolean ret = FALSE;
2633 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2634 g_return_val_if_fail (GST_PAD_IS_SINK (pad), FALSE);
2635 g_return_val_if_fail (format != GST_FORMAT_UNDEFINED, FALSE);
2637 query = gst_query_new_duration (format);
2638 if ((ret = gst_pad_peer_query (pad, query)))
2639 gst_query_parse_duration (query, NULL, duration);
2640 gst_query_unref (query);
2646 * gst_pad_query_convert:
2647 * @pad: a #GstPad to invoke the convert query on.
2648 * @src_format: a #GstFormat to convert from.
2649 * @src_val: a value to convert.
2650 * @dest_format: the #GstFormat to convert to.
2651 * @dest_val: (out): a pointer to the result.
2653 * Queries a pad to convert @src_val in @src_format to @dest_format.
2655 * Returns: TRUE if the query could be performed.
2658 gst_pad_query_convert (GstPad * pad, GstFormat src_format, gint64 src_val,
2659 GstFormat dest_format, gint64 * dest_val)
2664 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2665 g_return_val_if_fail (dest_format != GST_FORMAT_UNDEFINED, FALSE);
2666 g_return_val_if_fail (dest_val != NULL, FALSE);
2668 if (dest_format == src_format || src_val == -1) {
2669 *dest_val = src_val;
2673 query = gst_query_new_convert (src_format, src_val, dest_format);
2674 if ((ret = gst_pad_query (pad, query)))
2675 gst_query_parse_convert (query, NULL, NULL, NULL, dest_val);
2676 gst_query_unref (query);
2682 * gst_pad_peer_query_convert:
2683 * @pad: a #GstPad, on whose peer pad to invoke the convert query on.
2684 * Must be a sink pad.
2685 * @src_format: a #GstFormat to convert from.
2686 * @src_val: a value to convert.
2687 * @dest_format: the #GstFormat to convert to.
2688 * @dest_val: (out): a pointer to the result.
2690 * Queries the peer pad of a given sink pad to convert @src_val in @src_format
2693 * Returns: TRUE if the query could be performed.
2696 gst_pad_peer_query_convert (GstPad * pad, GstFormat src_format, gint64 src_val,
2697 GstFormat dest_format, gint64 * dest_val)
2700 gboolean ret = FALSE;
2702 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2703 g_return_val_if_fail (GST_PAD_IS_SINK (pad), FALSE);
2704 g_return_val_if_fail (dest_format != GST_FORMAT_UNDEFINED, FALSE);
2705 g_return_val_if_fail (dest_val != NULL, FALSE);
2707 query = gst_query_new_convert (src_format, src_val, dest_format);
2708 if ((ret = gst_pad_peer_query (pad, query)))
2709 gst_query_parse_convert (query, NULL, NULL, NULL, dest_val);
2710 gst_query_unref (query);
2716 * gst_pad_query_caps:
2717 * @pad: a #GstPad to get the capabilities of.
2718 * @filter: (allow-none): suggested #GstCaps, or NULL
2720 * Gets the capabilities this pad can produce or consume.
2721 * Note that this method doesn't necessarily return the caps set by
2722 * gst_pad_set_caps() - use gst_pad_get_current_caps() for that instead.
2723 * gst_pad_query_caps returns all possible caps a pad can operate with, using
2724 * the pad's CAPS query function, If the query fails, this function will return
2725 * @filter, if not #NULL, otherwise ANY.
2727 * When called on sinkpads @filter contains the caps that
2728 * upstream could produce in the order preferred by upstream. When
2729 * called on srcpads @filter contains the caps accepted by
2730 * downstream in the preffered order. @filter might be %NULL but
2731 * if it is not %NULL the returned caps will be a subset of @filter.
2733 * Note that this function does not return writable #GstCaps, use
2734 * gst_caps_make_writable() before modifying the caps.
2736 * Returns: (transfer full): the caps of the pad with incremented ref-count.
2739 gst_pad_query_caps (GstPad * pad, GstCaps * filter)
2741 GstCaps *result = NULL;
2744 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2745 g_return_val_if_fail (filter == NULL || GST_IS_CAPS (filter), NULL);
2747 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2748 "get pad caps with filter %" GST_PTR_FORMAT, filter);
2750 query = gst_query_new_caps (filter);
2751 if (gst_pad_query (pad, query)) {
2752 gst_query_parse_caps_result (query, &result);
2753 gst_caps_ref (result);
2754 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2755 "query returned %" GST_PTR_FORMAT, result);
2756 } else if (filter) {
2757 result = gst_caps_ref (filter);
2759 result = gst_caps_new_any ();
2761 gst_query_unref (query);
2767 * gst_pad_peer_query_caps:
2768 * @pad: a #GstPad to get the capabilities of.
2769 * @filter: (allow-none): a #GstCaps filter, or NULL.
2771 * Gets the capabilities of the peer connected to this pad. Similar to
2772 * gst_pad_query_caps().
2774 * When called on srcpads @filter contains the caps that
2775 * upstream could produce in the order preferred by upstream. When
2776 * called on sinkpads @filter contains the caps accepted by
2777 * downstream in the preffered order. @filter might be %NULL but
2778 * if it is not %NULL the returned caps will be a subset of @filter.
2780 * Returns: the caps of the peer pad with incremented ref-count. When there is
2781 * no peer pad, this function returns @filter or, when @filter is %NULL, ANY
2785 gst_pad_peer_query_caps (GstPad * pad, GstCaps * filter)
2787 GstCaps *result = NULL;
2790 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2791 g_return_val_if_fail (filter == NULL || GST_IS_CAPS (filter), NULL);
2793 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2794 "get pad peer caps with filter %" GST_PTR_FORMAT, filter);
2796 query = gst_query_new_caps (filter);
2797 if (gst_pad_peer_query (pad, query)) {
2798 gst_query_parse_caps_result (query, &result);
2799 gst_caps_ref (result);
2800 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2801 "peer query returned %" GST_PTR_FORMAT, result);
2802 } else if (filter) {
2803 result = gst_caps_ref (filter);
2805 result = gst_caps_new_any ();
2807 gst_query_unref (query);
2813 * gst_pad_query_accept_caps:
2814 * @pad: a #GstPad to check
2815 * @caps: a #GstCaps to check on the pad
2817 * Check if the given pad accepts the caps.
2819 * Returns: TRUE if the pad can accept the caps.
2822 gst_pad_query_accept_caps (GstPad * pad, GstCaps * caps)
2824 gboolean res = TRUE;
2827 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2828 g_return_val_if_fail (GST_IS_CAPS (caps), FALSE);
2830 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %"
2831 GST_PTR_FORMAT, caps);
2833 query = gst_query_new_accept_caps (caps);
2834 if (gst_pad_query (pad, query)) {
2835 gst_query_parse_accept_caps_result (query, &res);
2836 GST_DEBUG_OBJECT (pad, "query returned %d", res);
2838 gst_query_unref (query);
2844 * gst_pad_peer_query_accept_caps:
2845 * @pad: a #GstPad to check the peer of
2846 * @caps: a #GstCaps to check on the pad
2848 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2851 * Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
2854 gst_pad_peer_query_accept_caps (GstPad * pad, GstCaps * caps)
2856 gboolean res = TRUE;
2859 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2860 g_return_val_if_fail (GST_IS_CAPS (caps), FALSE);
2862 query = gst_query_new_accept_caps (caps);
2863 if (gst_pad_peer_query (pad, query)) {
2864 gst_query_parse_accept_caps_result (query, &res);
2865 GST_DEBUG_OBJECT (pad, "query returned %d", res);
2867 gst_query_unref (query);
2873 element_find_unlinked_pad (GstElement * element, GstPadDirection direction)
2876 GstPad *unlinked_pad = NULL;
2878 GValue data = { 0, };
2880 switch (direction) {
2882 iter = gst_element_iterate_src_pads (element);
2885 iter = gst_element_iterate_sink_pads (element);
2888 g_return_val_if_reached (NULL);
2893 switch (gst_iterator_next (iter, &data)) {
2894 case GST_ITERATOR_OK:{
2896 GstPad *pad = g_value_get_object (&data);
2898 GST_CAT_LOG (GST_CAT_ELEMENT_PADS, "examining pad %s:%s",
2899 GST_DEBUG_PAD_NAME (pad));
2901 peer = gst_pad_get_peer (pad);
2903 unlinked_pad = gst_object_ref (pad);
2905 GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS,
2906 "found existing unlinked pad %s:%s",
2907 GST_DEBUG_PAD_NAME (unlinked_pad));
2909 gst_object_unref (peer);
2911 g_value_reset (&data);
2914 case GST_ITERATOR_DONE:
2917 case GST_ITERATOR_RESYNC:
2918 gst_iterator_resync (iter);
2920 case GST_ITERATOR_ERROR:
2921 g_return_val_if_reached (NULL);
2925 g_value_unset (&data);
2926 gst_iterator_free (iter);
2928 return unlinked_pad;
2932 * gst_bin_find_unlinked_pad:
2933 * @bin: bin in which to look for elements with unlinked pads
2934 * @direction: whether to look for an unlinked source or sink pad
2936 * Recursively looks for elements with an unlinked pad of the given
2937 * direction within the specified bin and returns an unlinked pad
2938 * if one is found, or NULL otherwise. If a pad is found, the caller
2939 * owns a reference to it and should use gst_object_unref() on the
2940 * pad when it is not needed any longer.
2942 * Returns: (transfer full): unlinked pad of the given direction, or NULL.
2945 gst_bin_find_unlinked_pad (GstBin * bin, GstPadDirection direction)
2950 GValue data = { 0, };
2952 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2953 g_return_val_if_fail (direction != GST_PAD_UNKNOWN, NULL);
2956 iter = gst_bin_iterate_recurse (bin);
2958 switch (gst_iterator_next (iter, &data)) {
2959 case GST_ITERATOR_OK:{
2960 GstElement *element = g_value_get_object (&data);
2962 pad = element_find_unlinked_pad (element, direction);
2965 g_value_reset (&data);
2968 case GST_ITERATOR_DONE:
2971 case GST_ITERATOR_RESYNC:
2972 gst_iterator_resync (iter);
2974 case GST_ITERATOR_ERROR:
2975 g_return_val_if_reached (NULL);
2979 g_value_unset (&data);
2980 gst_iterator_free (iter);
2986 * gst_parse_bin_from_description:
2987 * @bin_description: command line describing the bin
2988 * @ghost_unlinked_pads: whether to automatically create ghost pads
2989 * for unlinked source or sink pads within the bin
2990 * @err: where to store the error message in case of an error, or NULL
2992 * This is a convenience wrapper around gst_parse_launch() to create a
2993 * #GstBin from a gst-launch-style pipeline description. See
2994 * gst_parse_launch() and the gst-launch man page for details about the
2995 * syntax. Ghost pads on the bin for unlinked source or sink pads
2996 * within the bin can automatically be created (but only a maximum of
2997 * one ghost pad for each direction will be created; if you expect
2998 * multiple unlinked source pads or multiple unlinked sink pads
2999 * and want them all ghosted, you will have to create the ghost pads
3002 * Returns: (transfer floating) (type Gst.Bin): a newly-created bin,
3003 * or %NULL if an error occurred.
3006 gst_parse_bin_from_description (const gchar * bin_description,
3007 gboolean ghost_unlinked_pads, GError ** err)
3009 return gst_parse_bin_from_description_full (bin_description,
3010 ghost_unlinked_pads, NULL, GST_PARSE_FLAG_NONE, err);
3014 * gst_parse_bin_from_description_full:
3015 * @bin_description: command line describing the bin
3016 * @ghost_unlinked_pads: whether to automatically create ghost pads
3017 * for unlinked source or sink pads within the bin
3018 * @context: (transfer none) (allow-none): a parse context allocated with
3019 * gst_parse_context_new(), or %NULL
3020 * @flags: parsing options, or #GST_PARSE_FLAG_NONE
3021 * @err: where to store the error message in case of an error, or NULL
3023 * This is a convenience wrapper around gst_parse_launch() to create a
3024 * #GstBin from a gst-launch-style pipeline description. See
3025 * gst_parse_launch() and the gst-launch man page for details about the
3026 * syntax. Ghost pads on the bin for unlinked source or sink pads
3027 * within the bin can automatically be created (but only a maximum of
3028 * one ghost pad for each direction will be created; if you expect
3029 * multiple unlinked source pads or multiple unlinked sink pads
3030 * and want them all ghosted, you will have to create the ghost pads
3033 * Returns: (transfer full) (type Gst.Bin): a newly-created bin, or
3034 * %NULL if an error occurred.
3037 gst_parse_bin_from_description_full (const gchar * bin_description,
3038 gboolean ghost_unlinked_pads, GstParseContext * context,
3039 GstParseFlags flags, GError ** err)
3041 #ifndef GST_DISABLE_PARSE
3046 g_return_val_if_fail (bin_description != NULL, NULL);
3047 g_return_val_if_fail (err == NULL || *err == NULL, NULL);
3049 GST_DEBUG ("Making bin from description '%s'", bin_description);
3051 /* parse the pipeline to a bin */
3052 desc = g_strdup_printf ("bin.( %s )", bin_description);
3053 bin = (GstBin *) gst_parse_launch_full (desc, context, flags, err);
3056 if (bin == NULL || (err && *err != NULL)) {
3058 gst_object_unref (bin);
3062 /* find pads and ghost them if necessary */
3063 if (ghost_unlinked_pads) {
3064 if ((pad = gst_bin_find_unlinked_pad (bin, GST_PAD_SRC))) {
3065 gst_element_add_pad (GST_ELEMENT (bin), gst_ghost_pad_new ("src", pad));
3066 gst_object_unref (pad);
3068 if ((pad = gst_bin_find_unlinked_pad (bin, GST_PAD_SINK))) {
3069 gst_element_add_pad (GST_ELEMENT (bin), gst_ghost_pad_new ("sink", pad));
3070 gst_object_unref (pad);
3074 return GST_ELEMENT (bin);
3078 GST_WARNING ("Disabled API called");
3080 msg = gst_error_get_message (GST_CORE_ERROR, GST_CORE_ERROR_DISABLED);
3081 g_set_error (err, GST_CORE_ERROR, GST_CORE_ERROR_DISABLED, "%s", msg);
3089 * gst_util_get_timestamp:
3091 * Get a timestamp as GstClockTime to be used for interval measurements.
3092 * The timestamp should not be interpreted in any other way.
3094 * Returns: the timestamp
3097 gst_util_get_timestamp (void)
3099 #if defined (HAVE_POSIX_TIMERS) && defined(HAVE_MONOTONIC_CLOCK)
3100 struct timespec now;
3102 clock_gettime (CLOCK_MONOTONIC, &now);
3103 return GST_TIMESPEC_TO_TIME (now);
3107 g_get_current_time (&now);
3108 return GST_TIMEVAL_TO_TIME (now);
3113 * gst_util_array_binary_search:
3114 * @array: the sorted input array
3115 * @num_elements: number of elements in the array
3116 * @element_size: size of every element in bytes
3117 * @search_func: (scope call): function to compare two elements, @search_data will always be passed as second argument
3118 * @mode: search mode that should be used
3119 * @search_data: element that should be found
3120 * @user_data: (closure): data to pass to @search_func
3122 * Searches inside @array for @search_data by using the comparison function
3123 * @search_func. @array must be sorted ascending.
3125 * As @search_data is always passed as second argument to @search_func it's
3126 * not required that @search_data has the same type as the array elements.
3128 * The complexity of this search function is O(log (num_elements)).
3130 * Returns: (transfer none): The address of the found element or %NULL if nothing was found
3133 gst_util_array_binary_search (gpointer array, guint num_elements,
3134 gsize element_size, GCompareDataFunc search_func, GstSearchMode mode,
3135 gconstpointer search_data, gpointer user_data)
3137 glong left = 0, right = num_elements - 1, m;
3139 guint8 *data = (guint8 *) array;
3141 g_return_val_if_fail (array != NULL, NULL);
3142 g_return_val_if_fail (element_size > 0, NULL);
3143 g_return_val_if_fail (search_func != NULL, NULL);
3145 /* 0. No elements => return NULL */
3146 if (num_elements == 0)
3149 /* 1. If search_data is before the 0th element return the 0th element */
3150 ret = search_func (data, search_data, user_data);
3151 if ((ret >= 0 && mode == GST_SEARCH_MODE_AFTER) || ret == 0)
3156 /* 2. If search_data is after the last element return the last element */
3158 search_func (data + (num_elements - 1) * element_size, search_data,
3160 if ((ret <= 0 && mode == GST_SEARCH_MODE_BEFORE) || ret == 0)
3161 return data + (num_elements - 1) * element_size;
3165 /* 3. else binary search */
3167 m = left + (right - left) / 2;
3169 ret = search_func (data + m * element_size, search_data, user_data);
3172 return data + m * element_size;
3173 } else if (ret < 0) {
3179 /* No exact match found */
3181 if (mode == GST_SEARCH_MODE_EXACT) {
3183 } else if (mode == GST_SEARCH_MODE_AFTER) {
3185 return (m < num_elements) ? data + (m + 1) * element_size : NULL;
3187 return data + m * element_size;
3190 return data + m * element_size;
3192 return (m > 0) ? data + (m - 1) * element_size : NULL;
3198 /* Finds the greatest common divisor.
3199 * Returns 1 if none other found.
3200 * This is Euclid's algorithm. */
3203 * gst_util_greatest_common_divisor:
3204 * @a: First value as #gint
3205 * @b: Second value as #gint
3207 * Calculates the greatest common divisor of @a
3210 * Returns: Greatest common divisor of @a and @b
3213 gst_util_greatest_common_divisor (gint a, gint b)
3226 * gst_util_greatest_common_divisor_int64:
3227 * @a: First value as #gint64
3228 * @b: Second value as #gint64
3230 * Calculates the greatest common divisor of @a
3233 * Returns: Greatest common divisor of @a and @b
3236 gst_util_greatest_common_divisor_int64 (gint64 a, gint64 b)
3250 * gst_util_fraction_to_double:
3251 * @src_n: Fraction numerator as #gint
3252 * @src_d: Fraction denominator #gint
3253 * @dest: (out): pointer to a #gdouble for the result
3255 * Transforms a fraction to a #gdouble.
3258 gst_util_fraction_to_double (gint src_n, gint src_d, gdouble * dest)
3260 g_return_if_fail (dest != NULL);
3261 g_return_if_fail (src_d != 0);
3263 *dest = ((gdouble) src_n) / ((gdouble) src_d);
3266 #define MAX_TERMS 30
3267 #define MIN_DIVISOR 1.0e-10
3268 #define MAX_ERROR 1.0e-20
3270 /* use continued fractions to transform a double into a fraction,
3271 * see http://mathforum.org/dr.math/faq/faq.fractions.html#decfrac.
3272 * This algorithm takes care of overflows.
3276 * gst_util_double_to_fraction:
3277 * @src: #gdouble to transform
3278 * @dest_n: (out): pointer to a #gint to hold the result numerator
3279 * @dest_d: (out): pointer to a #gint to hold the result denominator
3281 * Transforms a #gdouble to a fraction and simplifies
3285 gst_util_double_to_fraction (gdouble src, gint * dest_n, gint * dest_d)
3288 gdouble V, F; /* double being converted */
3289 gint N, D; /* will contain the result */
3290 gint A; /* current term in continued fraction */
3291 gint64 N1, D1; /* numerator, denominator of last approx */
3292 gint64 N2, D2; /* numerator, denominator of previous approx */
3295 gboolean negative = FALSE;
3297 g_return_if_fail (dest_n != NULL);
3298 g_return_if_fail (dest_d != NULL);
3300 /* initialize fraction being converted */
3308 /* initialize fractions with 1/0, 0/1 */
3316 for (i = 0; i < MAX_TERMS; i++) {
3318 A = (gint) F; /* no floor() needed, F is always >= 0 */
3319 /* get new divisor */
3322 /* calculate new fraction in temp */
3326 /* guard against overflow */
3327 if (N2 > G_MAXINT || D2 > G_MAXINT) {
3334 /* save last two fractions */
3340 /* quit if dividing by zero or close enough to target */
3341 if (F < MIN_DIVISOR || fabs (V - ((gdouble) N) / D) < MAX_ERROR) {
3345 /* Take reciprocal */
3348 /* fix for overflow */
3353 /* fix for negative */
3358 gcd = gst_util_greatest_common_divisor (N, D);
3370 * gst_util_fraction_multiply:
3371 * @a_n: Numerator of first value
3372 * @a_d: Denominator of first value
3373 * @b_n: Numerator of second value
3374 * @b_d: Denominator of second value
3375 * @res_n: (out): Pointer to #gint to hold the result numerator
3376 * @res_d: (out): Pointer to #gint to hold the result denominator
3378 * Multiplies the fractions @a_n/@a_d and @b_n/@b_d and stores
3379 * the result in @res_n and @res_d.
3381 * Returns: %FALSE on overflow, %TRUE otherwise.
3384 gst_util_fraction_multiply (gint a_n, gint a_d, gint b_n, gint b_d,
3385 gint * res_n, gint * res_d)
3389 g_return_val_if_fail (res_n != NULL, FALSE);
3390 g_return_val_if_fail (res_d != NULL, FALSE);
3391 g_return_val_if_fail (a_d != 0, FALSE);
3392 g_return_val_if_fail (b_d != 0, FALSE);
3394 gcd = gst_util_greatest_common_divisor (a_n, a_d);
3398 gcd = gst_util_greatest_common_divisor (b_n, b_d);
3402 gcd = gst_util_greatest_common_divisor (a_n, b_d);
3406 gcd = gst_util_greatest_common_divisor (a_d, b_n);
3410 /* This would result in overflow */
3411 if (a_n != 0 && G_MAXINT / ABS (a_n) < ABS (b_n))
3413 if (G_MAXINT / ABS (a_d) < ABS (b_d))
3419 gcd = gst_util_greatest_common_divisor (*res_n, *res_d);
3427 * gst_util_fraction_add:
3428 * @a_n: Numerator of first value
3429 * @a_d: Denominator of first value
3430 * @b_n: Numerator of second value
3431 * @b_d: Denominator of second value
3432 * @res_n: (out): Pointer to #gint to hold the result numerator
3433 * @res_d: (out): Pointer to #gint to hold the result denominator
3435 * Adds the fractions @a_n/@a_d and @b_n/@b_d and stores
3436 * the result in @res_n and @res_d.
3438 * Returns: %FALSE on overflow, %TRUE otherwise.
3441 gst_util_fraction_add (gint a_n, gint a_d, gint b_n, gint b_d, gint * res_n,
3446 g_return_val_if_fail (res_n != NULL, FALSE);
3447 g_return_val_if_fail (res_d != NULL, FALSE);
3448 g_return_val_if_fail (a_d != 0, FALSE);
3449 g_return_val_if_fail (b_d != 0, FALSE);
3451 gcd = gst_util_greatest_common_divisor (a_n, a_d);
3455 gcd = gst_util_greatest_common_divisor (b_n, b_d);
3470 /* This would result in overflow */
3471 if (G_MAXINT / ABS (a_n) < ABS (b_n))
3473 if (G_MAXINT / ABS (a_d) < ABS (b_d))
3475 if (G_MAXINT / ABS (a_d) < ABS (b_d))
3478 *res_n = (a_n * b_d) + (a_d * b_n);
3481 gcd = gst_util_greatest_common_divisor (*res_n, *res_d);
3494 * gst_util_fraction_compare:
3495 * @a_n: Numerator of first value
3496 * @a_d: Denominator of first value
3497 * @b_n: Numerator of second value
3498 * @b_d: Denominator of second value
3500 * Compares the fractions @a_n/@a_d and @b_n/@b_d and returns
3501 * -1 if a < b, 0 if a = b and 1 if a > b.
3503 * Returns: -1 if a < b; 0 if a = b; 1 if a > b.
3506 gst_util_fraction_compare (gint a_n, gint a_d, gint b_n, gint b_d)
3512 g_return_val_if_fail (a_d != 0 && b_d != 0, 0);
3515 gcd = gst_util_greatest_common_divisor (a_n, a_d);
3519 gcd = gst_util_greatest_common_divisor (b_n, b_d);
3523 /* fractions are reduced when set, so we can quickly see if they're equal */
3524 if (a_n == b_n && a_d == b_d)
3527 /* extend to 64 bits */
3528 new_num_1 = ((gint64) a_n) * b_d;
3529 new_num_2 = ((gint64) b_n) * a_d;
3530 if (new_num_1 < new_num_2)
3532 if (new_num_1 > new_num_2)
3535 /* Should not happen because a_d and b_d are not 0 */
3536 g_return_val_if_reached (0);
3540 * gst_pad_create_stream_id_printf_valist:
3541 * @pad: A source #GstPad
3542 * @parent: Parent #GstElement of @pad
3543 * @stream_id: (allow-none): The stream-id
3544 * @var_args: parameters for the @stream_id format string
3546 * Creates a stream-id for the source #GstPad @pad by combining the
3547 * upstream information with the optional @stream_id of the stream
3548 * of @pad. @pad must have a parent #GstElement and which must have zero
3549 * or one sinkpad. @stream_id can only be %NULL if the parent element
3550 * of @pad has only a single source pad.
3552 * This function generates an unique stream-id by getting the upstream
3553 * stream-start event stream ID and appending @stream_id to it. If the
3554 * element has no sinkpad it will generate an upstream stream-id by
3555 * doing an URI query on the element and in the worst case just uses
3556 * a random number. Source elements that don't implement the URI
3557 * handler interface should ideally generate a unique, deterministic
3558 * stream-id manually instead.
3560 * Returns: A stream-id for @pad. g_free() after usage.
3563 gst_pad_create_stream_id_printf_valist (GstPad * pad, GstElement * parent,
3564 const gchar * stream_id, va_list var_args)
3566 GstEvent *upstream_event;
3567 gchar *upstream_stream_id = NULL, *new_stream_id;
3570 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3571 g_return_val_if_fail (GST_PAD_IS_SRC (pad), NULL);
3572 g_return_val_if_fail (GST_IS_ELEMENT (parent), NULL);
3574 g_return_val_if_fail (parent->numsinkpads <= 1, NULL);
3576 /* If the element has multiple source pads it must
3577 * provide a stream-id for every source pad, otherwise
3578 * all source pads will have the same and are not
3579 * distinguishable */
3580 g_return_val_if_fail (parent->numsrcpads == 1 || stream_id, NULL);
3582 /* First try to get the upstream stream-start stream-id from the sinkpad.
3583 * This will only work for non-source elements */
3584 sinkpad = gst_element_get_static_pad (parent, "sink");
3587 gst_pad_get_sticky_event (sinkpad, GST_EVENT_STREAM_START, 0);
3588 if (upstream_event) {
3591 gst_event_parse_stream_start (upstream_event, &tmp);
3593 upstream_stream_id = g_strdup (tmp);
3594 gst_event_unref (upstream_event);
3596 gst_object_unref (sinkpad);
3599 /* The only case where we don't have an upstream start-start event
3600 * here is for source elements */
3601 if (!upstream_stream_id) {
3604 /* Try to generate one from the URI query and
3605 * if it fails take a random number instead */
3606 query = gst_query_new_uri ();
3607 if (gst_element_query (parent, query)) {
3611 gst_query_parse_uri (query, &uri);
3613 /* And then generate an SHA256 sum of the URI */
3614 cs = g_checksum_new (G_CHECKSUM_SHA256);
3615 g_checksum_update (cs, (const guchar *) uri, strlen (uri));
3617 upstream_stream_id = g_strdup (g_checksum_get_string (cs));
3618 g_checksum_free (cs);
3620 /* Just get some random number if the URI query fails */
3621 GST_WARNING_OBJECT (pad, "Creating random stream-id, consider "
3622 "implementing a deterministic way of creating a stream-id");
3623 upstream_stream_id =
3624 g_strdup_printf ("%08x%08x%08x%08x", g_random_int (), g_random_int (),
3625 g_random_int (), g_random_int ());
3628 gst_query_unref (query);
3632 gchar *expanded = g_strdup_vprintf (stream_id, var_args);
3633 new_stream_id = g_strconcat (upstream_stream_id, "/", expanded, NULL);
3636 new_stream_id = g_strdup (upstream_stream_id);
3639 g_free (upstream_stream_id);
3641 return new_stream_id;
3645 * gst_pad_create_stream_id_printf:
3646 * @pad: A source #GstPad
3647 * @parent: Parent #GstElement of @pad
3648 * @stream_id: (allow-none): The stream-id
3649 * @...: parameters for the @stream_id format string
3651 * Creates a stream-id for the source #GstPad @pad by combining the
3652 * upstream information with the optional @stream_id of the stream
3653 * of @pad. @pad must have a parent #GstElement and which must have zero
3654 * or one sinkpad. @stream_id can only be %NULL if the parent element
3655 * of @pad has only a single source pad.
3657 * This function generates an unique stream-id by getting the upstream
3658 * stream-start event stream ID and appending @stream_id to it. If the
3659 * element has no sinkpad it will generate an upstream stream-id by
3660 * doing an URI query on the element and in the worst case just uses
3661 * a random number. Source elements that don't implement the URI
3662 * handler interface should ideally generate a unique, deterministic
3663 * stream-id manually instead.
3665 * Returns: A stream-id for @pad. g_free() after usage.
3668 gst_pad_create_stream_id_printf (GstPad * pad, GstElement * parent,
3669 const gchar * stream_id, ...)
3672 gchar *new_stream_id;
3674 va_start (var_args, stream_id);
3676 gst_pad_create_stream_id_printf_valist (pad, parent, stream_id, var_args);
3679 return new_stream_id;
3683 * gst_pad_create_stream_id:
3684 * @pad: A source #GstPad
3685 * @parent: Parent #GstElement of @pad
3686 * @stream_id: (allow-none): The stream-id
3688 * Creates a stream-id for the source #GstPad @pad by combining the
3689 * upstream information with the optional @stream_id of the stream
3690 * of @pad. @pad must have a parent #GstElement and which must have zero
3691 * or one sinkpad. @stream_id can only be %NULL if the parent element
3692 * of @pad has only a single source pad.
3694 * This function generates an unique stream-id by getting the upstream
3695 * stream-start event stream ID and appending @stream_id to it. If the
3696 * element has no sinkpad it will generate an upstream stream-id by
3697 * doing an URI query on the element and in the worst case just uses
3698 * a random number. Source elements that don't implement the URI
3699 * handler interface should ideally generate a unique, deterministic
3700 * stream-id manually instead.
3702 * Returns: A stream-id for @pad. g_free() after usage.
3705 gst_pad_create_stream_id (GstPad * pad, GstElement * parent,
3706 const gchar * stream_id)
3708 return gst_pad_create_stream_id_printf (pad, parent, stream_id, NULL);