3 * Copyright (C) 2001-2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
4 * 2006 Edgard Lima <edgard.lima@indt.org.br>
6 * gstv4l2src.c: Video4Linux2 source element
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
25 * SECTION:element-v4l2src
27 * v4l2src can be used to capture video from v4l2 devices, like webcams and tv
31 * <title>Example launch lines</title>
33 * gst-launch-1.0 v4l2src ! xvimagesink
34 * ]| This pipeline shows the video captured from /dev/video0 tv card and for
37 * gst-launch-1.0 v4l2src ! jpegdec ! xvimagesink
38 * ]| This pipeline shows the video captured from a webcam that delivers jpeg
53 #include <gst/video/gstvideometa.h>
54 #include <gst/video/gstvideopool.h>
56 #include "gstv4l2src.h"
58 #include "gstv4l2colorbalance.h"
59 #include "gstv4l2tuner.h"
61 #include "gstv4l2xoverlay.h"
63 #include "gstv4l2vidorient.h"
65 #include "gst/gst-i18n-plugin.h"
67 GST_DEBUG_CATEGORY (v4l2src_debug);
68 #define GST_CAT_DEFAULT v4l2src_debug
70 #define DEFAULT_PROP_DEVICE "/dev/video0"
75 V4L2_STD_OBJECT_PROPS,
79 /* signals and args */
82 SIGNAL_PRE_SET_FORMAT,
86 static guint gst_v4l2_signals[LAST_SIGNAL] = { 0 };
88 GST_IMPLEMENT_V4L2_COLOR_BALANCE_METHODS (GstV4l2Src, gst_v4l2src);
89 GST_IMPLEMENT_V4L2_TUNER_METHODS (GstV4l2Src, gst_v4l2src);
91 GST_IMPLEMENT_V4L2_XOVERLAY_METHODS (GstV4l2Src, gst_v4l2src);
93 GST_IMPLEMENT_V4L2_VIDORIENT_METHODS (GstV4l2Src, gst_v4l2src);
95 static void gst_v4l2src_uri_handler_init (gpointer g_iface,
98 #define gst_v4l2src_parent_class parent_class
99 G_DEFINE_TYPE_WITH_CODE (GstV4l2Src, gst_v4l2src, GST_TYPE_PUSH_SRC,
100 G_IMPLEMENT_INTERFACE (GST_TYPE_URI_HANDLER, gst_v4l2src_uri_handler_init);
101 G_IMPLEMENT_INTERFACE (GST_TYPE_TUNER, gst_v4l2src_tuner_interface_init);
103 /* FIXME: does GstXOverlay for v4l2src make sense in a GStreamer context? */
104 G_IMPLEMENT_INTERFACE (GST_TYPE_X_OVERLAY,
105 gst_v4l2src_xoverlay_interface_init);
107 G_IMPLEMENT_INTERFACE (GST_TYPE_COLOR_BALANCE,
108 gst_v4l2src_color_balance_interface_init);
109 G_IMPLEMENT_INTERFACE (GST_TYPE_VIDEO_ORIENTATION,
110 gst_v4l2src_video_orientation_interface_init));
112 static void gst_v4l2src_dispose (GObject * object);
113 static void gst_v4l2src_finalize (GstV4l2Src * v4l2src);
115 /* element methods */
116 static GstStateChangeReturn gst_v4l2src_change_state (GstElement * element,
117 GstStateChange transition);
119 /* basesrc methods */
120 static gboolean gst_v4l2src_start (GstBaseSrc * src);
121 static gboolean gst_v4l2src_unlock (GstBaseSrc * src);
122 static gboolean gst_v4l2src_unlock_stop (GstBaseSrc * src);
123 static gboolean gst_v4l2src_stop (GstBaseSrc * src);
124 static gboolean gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps);
125 static GstCaps *gst_v4l2src_get_caps (GstBaseSrc * src, GstCaps * filter);
126 static gboolean gst_v4l2src_query (GstBaseSrc * bsrc, GstQuery * query);
127 static gboolean gst_v4l2src_decide_allocation (GstBaseSrc * src,
129 static GstFlowReturn gst_v4l2src_fill (GstPushSrc * src, GstBuffer * out);
130 static GstCaps *gst_v4l2src_fixate (GstBaseSrc * basesrc, GstCaps * caps);
131 static gboolean gst_v4l2src_event (GstBaseSrc * src, GstEvent * event);
132 static gboolean gst_v4l2src_negotiate (GstBaseSrc * basesrc);
134 static void gst_v4l2src_set_property (GObject * object, guint prop_id,
135 const GValue * value, GParamSpec * pspec);
136 static void gst_v4l2src_get_property (GObject * object, guint prop_id,
137 GValue * value, GParamSpec * pspec);
140 gst_v4l2src_class_init (GstV4l2SrcClass * klass)
142 GObjectClass *gobject_class;
143 GstElementClass *element_class;
144 GstBaseSrcClass *basesrc_class;
145 GstPushSrcClass *pushsrc_class;
147 gobject_class = G_OBJECT_CLASS (klass);
148 element_class = GST_ELEMENT_CLASS (klass);
149 basesrc_class = GST_BASE_SRC_CLASS (klass);
150 pushsrc_class = GST_PUSH_SRC_CLASS (klass);
152 gobject_class->dispose = gst_v4l2src_dispose;
153 gobject_class->finalize = (GObjectFinalizeFunc) gst_v4l2src_finalize;
154 gobject_class->set_property = gst_v4l2src_set_property;
155 gobject_class->get_property = gst_v4l2src_get_property;
157 element_class->change_state = gst_v4l2src_change_state;
159 gst_v4l2_object_install_properties_helper (gobject_class,
160 DEFAULT_PROP_DEVICE);
163 * GstV4l2Src::prepare-format:
164 * @v4l2src: the v4l2src instance
165 * @fd: the file descriptor of the current device
166 * @caps: the caps of the format being set
168 * This signal gets emitted before calling the v4l2 VIDIOC_S_FMT ioctl
169 * (set format). This allows for any custom configuration of the device to
170 * happen prior to the format being set.
171 * This is mostly useful for UVC H264 encoding cameras which need the H264
172 * Probe & Commit to happen prior to the normal Probe & Commit.
176 gst_v4l2_signals[SIGNAL_PRE_SET_FORMAT] = g_signal_new ("prepare-format",
177 G_TYPE_FROM_CLASS (klass),
179 0, NULL, NULL, NULL, G_TYPE_NONE, 2, G_TYPE_INT, GST_TYPE_CAPS);
181 gst_element_class_set_static_metadata (element_class,
182 "Video (video4linux2) Source", "Source/Video",
183 "Reads frames from a Video4Linux2 device",
184 "Edgard Lima <edgard.lima@indt.org.br>, "
185 "Stefan Kost <ensonic@users.sf.net>");
187 gst_element_class_add_pad_template
189 gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
190 gst_v4l2_object_get_all_caps ()));
192 basesrc_class->get_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_get_caps);
193 basesrc_class->set_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_set_caps);
194 basesrc_class->start = GST_DEBUG_FUNCPTR (gst_v4l2src_start);
195 basesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock);
196 basesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock_stop);
197 basesrc_class->stop = GST_DEBUG_FUNCPTR (gst_v4l2src_stop);
198 basesrc_class->query = GST_DEBUG_FUNCPTR (gst_v4l2src_query);
199 basesrc_class->fixate = GST_DEBUG_FUNCPTR (gst_v4l2src_fixate);
200 basesrc_class->event = GST_DEBUG_FUNCPTR (gst_v4l2src_event);
201 basesrc_class->negotiate = GST_DEBUG_FUNCPTR (gst_v4l2src_negotiate);
202 basesrc_class->decide_allocation =
203 GST_DEBUG_FUNCPTR (gst_v4l2src_decide_allocation);
205 pushsrc_class->fill = GST_DEBUG_FUNCPTR (gst_v4l2src_fill);
207 klass->v4l2_class_devices = NULL;
209 GST_DEBUG_CATEGORY_INIT (v4l2src_debug, "v4l2src", 0, "V4L2 source element");
213 gst_v4l2src_init (GstV4l2Src * v4l2src)
215 /* fixme: give an update_fps_function */
216 v4l2src->v4l2object = gst_v4l2_object_new (GST_ELEMENT (v4l2src),
217 V4L2_BUF_TYPE_VIDEO_CAPTURE, DEFAULT_PROP_DEVICE,
218 gst_v4l2_get_input, gst_v4l2_set_input, NULL);
220 gst_base_src_set_format (GST_BASE_SRC (v4l2src), GST_FORMAT_TIME);
221 gst_base_src_set_live (GST_BASE_SRC (v4l2src), TRUE);
225 gst_v4l2src_dispose (GObject * object)
227 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
229 if (v4l2src->probed_caps) {
230 gst_caps_unref (v4l2src->probed_caps);
233 G_OBJECT_CLASS (parent_class)->dispose (object);
238 gst_v4l2src_finalize (GstV4l2Src * v4l2src)
240 gst_v4l2_object_destroy (v4l2src->v4l2object);
242 G_OBJECT_CLASS (parent_class)->finalize ((GObject *) (v4l2src));
247 gst_v4l2src_set_property (GObject * object,
248 guint prop_id, const GValue * value, GParamSpec * pspec)
250 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
252 if (!gst_v4l2_object_set_property_helper (v4l2src->v4l2object,
253 prop_id, value, pspec)) {
256 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
263 gst_v4l2src_get_property (GObject * object,
264 guint prop_id, GValue * value, GParamSpec * pspec)
266 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
268 if (!gst_v4l2_object_get_property_helper (v4l2src->v4l2object,
269 prop_id, value, pspec)) {
272 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
278 /* this function is a bit of a last resort */
280 gst_v4l2src_fixate (GstBaseSrc * basesrc, GstCaps * caps)
282 GstStructure *structure;
285 GST_DEBUG_OBJECT (basesrc, "fixating caps %" GST_PTR_FORMAT, caps);
287 caps = gst_caps_make_writable (caps);
289 for (i = 0; i < gst_caps_get_size (caps); ++i) {
290 structure = gst_caps_get_structure (caps, i);
292 /* We are fixating to a resonable 320x200 resolution
293 and the maximum framerate resolution for that size */
294 gst_structure_fixate_field_nearest_int (structure, "width", 320);
295 gst_structure_fixate_field_nearest_int (structure, "height", 200);
296 gst_structure_fixate_field_nearest_fraction (structure, "framerate",
298 gst_structure_fixate_field (structure, "format");
301 GST_DEBUG_OBJECT (basesrc, "fixated caps %" GST_PTR_FORMAT, caps);
303 caps = GST_BASE_SRC_CLASS (parent_class)->fixate (basesrc, caps);
310 gst_v4l2src_event (GstBaseSrc * src, GstEvent * event)
312 GST_DEBUG_OBJECT (src, "handle event %" GST_PTR_FORMAT, event);
314 switch (GST_EVENT_TYPE (event)) {
315 case GST_EVENT_RECONFIGURE:
316 gst_pad_check_reconfigure (GST_BASE_SRC_PAD (src));
321 return GST_BASE_SRC_CLASS (parent_class)->event (src, event);
326 gst_v4l2src_negotiate (GstBaseSrc * basesrc)
329 GstCaps *caps = NULL;
330 GstCaps *peercaps = NULL;
331 gboolean result = FALSE;
333 /* first see what is possible on our source pad */
334 thiscaps = gst_pad_query_caps (GST_BASE_SRC_PAD (basesrc), NULL);
335 GST_DEBUG_OBJECT (basesrc, "caps of src: %" GST_PTR_FORMAT, thiscaps);
336 LOG_CAPS (basesrc, thiscaps);
338 /* nothing or anything is allowed, we're done */
339 if (thiscaps == NULL || gst_caps_is_any (thiscaps))
342 /* get the peer caps */
343 peercaps = gst_pad_peer_query_caps (GST_BASE_SRC_PAD (basesrc), thiscaps);
344 GST_DEBUG_OBJECT (basesrc, "caps of peer: %" GST_PTR_FORMAT, peercaps);
345 LOG_CAPS (basesrc, peercaps);
346 if (peercaps && !gst_caps_is_any (peercaps)) {
347 GstCaps *icaps = NULL;
350 /* Prefer the first caps we are compatible with that the peer proposed */
351 for (i = 0; i < gst_caps_get_size (peercaps); i++) {
352 /* get intersection */
353 GstCaps *ipcaps = gst_caps_copy_nth (peercaps, i);
355 GST_DEBUG_OBJECT (basesrc, "peer: %" GST_PTR_FORMAT, ipcaps);
356 LOG_CAPS (basesrc, ipcaps);
358 icaps = gst_caps_intersect (thiscaps, ipcaps);
359 gst_caps_unref (ipcaps);
361 if (!gst_caps_is_empty (icaps))
364 gst_caps_unref (icaps);
368 GST_DEBUG_OBJECT (basesrc, "intersect: %" GST_PTR_FORMAT, icaps);
369 LOG_CAPS (basesrc, icaps);
371 /* If there are multiple intersections pick the one with the smallest
372 * resolution strictly bigger then the first peer caps */
373 if (gst_caps_get_size (icaps) > 1) {
374 GstStructure *s = gst_caps_get_structure (peercaps, 0);
377 int width = G_MAXINT, height = G_MAXINT;
379 if (gst_structure_get_int (s, "width", &twidth)
380 && gst_structure_get_int (s, "height", &theight)) {
382 /* Walk the structure backwards to get the first entry of the
383 * smallest resolution bigger (or equal to) the preferred resolution)
385 for (i = gst_caps_get_size (icaps) - 1; i >= 0; i--) {
386 GstStructure *is = gst_caps_get_structure (icaps, i);
389 if (gst_structure_get_int (is, "width", &w)
390 && gst_structure_get_int (is, "height", &h)) {
391 if (w >= twidth && w <= width && h >= theight && h <= height) {
400 caps = gst_caps_copy_nth (icaps, best);
401 gst_caps_unref (icaps);
406 gst_caps_unref (thiscaps);
408 /* no peer or peer have ANY caps, work with our own caps then */
412 gst_caps_unref (peercaps);
414 caps = gst_caps_truncate (caps);
417 if (!gst_caps_is_empty (caps)) {
418 caps = gst_v4l2src_fixate (basesrc, caps);
419 GST_DEBUG_OBJECT (basesrc, "fixated to: %" GST_PTR_FORMAT, caps);
420 LOG_CAPS (basesrc, caps);
422 if (gst_caps_is_any (caps)) {
423 /* hmm, still anything, so element can do anything and
424 * nego is not needed */
426 } else if (gst_caps_is_fixed (caps)) {
427 /* yay, fixed caps, use those then */
428 result = gst_base_src_set_caps (basesrc, caps);
431 gst_caps_unref (caps);
437 GST_DEBUG_OBJECT (basesrc, "no negotiation needed");
439 gst_caps_unref (thiscaps);
445 gst_v4l2src_get_caps (GstBaseSrc * src, GstCaps * filter)
453 v4l2src = GST_V4L2SRC (src);
454 obj = v4l2src->v4l2object;
456 if (!GST_V4L2_IS_OPEN (obj)) {
457 return gst_pad_get_pad_template_caps (GST_BASE_SRC_PAD (v4l2src));
460 if (v4l2src->probed_caps)
461 return gst_caps_ref (v4l2src->probed_caps);
463 formats = gst_v4l2_object_get_format_list (obj);
465 ret = gst_caps_new_empty ();
467 for (walk = formats; walk; walk = walk->next) {
468 struct v4l2_fmtdesc *format;
469 GstStructure *template;
471 format = (struct v4l2_fmtdesc *) walk->data;
473 template = gst_v4l2_object_v4l2fourcc_to_structure (format->pixelformat);
479 gst_v4l2_object_probe_caps_for_format (obj,
480 format->pixelformat, template);
482 gst_caps_append (ret, tmp);
484 gst_structure_free (template);
486 GST_DEBUG_OBJECT (v4l2src, "unknown format %u", format->pixelformat);
490 v4l2src->probed_caps = gst_caps_ref (ret);
492 GST_INFO_OBJECT (v4l2src, "probed caps: %" GST_PTR_FORMAT, ret);
498 gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps)
503 v4l2src = GST_V4L2SRC (src);
504 obj = v4l2src->v4l2object;
506 /* make sure we stop capturing and dealloc buffers */
507 if (!gst_v4l2_object_stop (obj))
510 g_signal_emit (v4l2src, gst_v4l2_signals[SIGNAL_PRE_SET_FORMAT], 0,
511 v4l2src->v4l2object->video_fd, caps);
513 if (!gst_v4l2_object_set_format (obj, caps))
514 /* error already posted */
521 gst_v4l2src_decide_allocation (GstBaseSrc * bsrc, GstQuery * query)
526 guint size, min, max;
529 src = GST_V4L2SRC (bsrc);
530 obj = src->v4l2object;
532 if (gst_query_get_n_allocation_pools (query) > 0) {
533 gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);
542 GST_DEBUG_OBJECT (src, "allocation: size:%u min:%u max:%u pool:%"
543 GST_PTR_FORMAT, size, min, max, pool);
546 /* if there is a min-buffers suggestion, use it. We add 1 because we need 1
547 * buffer extra to capture while the other two buffers are downstream */
557 /* no downstream pool, use our own then */
558 GST_DEBUG_OBJECT (src,
559 "read/write mode: no downstream pool, using our own");
560 pool = GST_BUFFER_POOL_CAST (obj->pool);
561 size = obj->sizeimage;
563 /* in READ/WRITE mode, prefer a downstream pool because our own pool
564 * doesn't help much, we have to write to it as well */
565 GST_DEBUG_OBJECT (src, "read/write mode: using downstream pool");
566 /* use the bigest size, when we use our own pool we can't really do any
567 * other size than what the hardware gives us but for downstream pools
569 size = MAX (size, obj->sizeimage);
572 case GST_V4L2_IO_MMAP:
573 case GST_V4L2_IO_USERPTR:
574 /* in streaming mode, prefer our own pool */
575 pool = GST_BUFFER_POOL_CAST (obj->pool);
576 size = obj->sizeimage;
577 GST_DEBUG_OBJECT (src,
578 "streaming mode: using our own pool %" GST_PTR_FORMAT, pool);
580 case GST_V4L2_IO_AUTO:
582 GST_WARNING_OBJECT (src, "unhandled mode");
587 GstStructure *config;
590 config = gst_buffer_pool_get_config (pool);
591 gst_buffer_pool_config_get_params (config, &caps, NULL, NULL, NULL);
592 gst_buffer_pool_config_set_params (config, caps, size, min, max);
594 /* if downstream supports video metadata, add this to the pool config */
595 if (gst_query_find_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL)) {
596 GST_DEBUG_OBJECT (pool, "activate Video Meta");
597 gst_buffer_pool_config_add_option (config,
598 GST_BUFFER_POOL_OPTION_VIDEO_META);
601 gst_buffer_pool_set_config (pool, config);
605 gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
607 gst_query_add_allocation_pool (query, pool, size, min, max);
609 return GST_BASE_SRC_CLASS (parent_class)->decide_allocation (bsrc, query);
613 gst_v4l2src_query (GstBaseSrc * bsrc, GstQuery * query)
617 gboolean res = FALSE;
619 src = GST_V4L2SRC (bsrc);
620 obj = src->v4l2object;
622 switch (GST_QUERY_TYPE (query)) {
623 case GST_QUERY_LATENCY:{
624 GstClockTime min_latency, max_latency;
625 guint32 fps_n, fps_d;
626 guint num_buffers = 0;
628 /* device must be open */
629 if (!GST_V4L2_IS_OPEN (obj)) {
630 GST_WARNING_OBJECT (src,
631 "Can't give latency since device isn't open !");
635 fps_n = GST_V4L2_FPS_N (obj);
636 fps_d = GST_V4L2_FPS_D (obj);
638 /* we must have a framerate */
639 if (fps_n <= 0 || fps_d <= 0) {
640 GST_WARNING_OBJECT (src,
641 "Can't give latency since framerate isn't fixated !");
645 /* min latency is the time to capture one frame */
646 min_latency = gst_util_uint64_scale_int (GST_SECOND, fps_d, fps_n);
648 /* max latency is total duration of the frame buffer */
649 if (obj->pool != NULL)
650 num_buffers = GST_V4L2_BUFFER_POOL_CAST (obj->pool)->num_buffers;
652 if (num_buffers == 0)
655 max_latency = num_buffers * min_latency;
657 GST_DEBUG_OBJECT (bsrc,
658 "report latency min %" GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
659 GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));
661 /* we are always live, the min latency is 1 frame and the max latency is
662 * the complete buffer of frames. */
663 gst_query_set_latency (query, TRUE, min_latency, max_latency);
669 res = GST_BASE_SRC_CLASS (parent_class)->query (bsrc, query);
678 /* start and stop are not symmetric -- start will open the device, but not start
679 * capture. it's setcaps that will start capture, which is called via basesrc's
680 * negotiate method. stop will both stop capture and close the device.
683 gst_v4l2src_start (GstBaseSrc * src)
685 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
689 /* activate settings for first frame */
690 v4l2src->ctrl_time = 0;
691 gst_object_sync_values (GST_OBJECT (src), v4l2src->ctrl_time);
697 gst_v4l2src_unlock (GstBaseSrc * src)
699 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
700 return gst_v4l2_object_unlock (v4l2src->v4l2object);
704 gst_v4l2src_unlock_stop (GstBaseSrc * src)
706 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
707 return gst_v4l2_object_unlock_stop (v4l2src->v4l2object);
711 gst_v4l2src_stop (GstBaseSrc * src)
713 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
714 GstV4l2Object *obj = v4l2src->v4l2object;
716 if (GST_V4L2_IS_ACTIVE (obj)) {
717 if (!gst_v4l2_object_stop (obj))
723 static GstStateChangeReturn
724 gst_v4l2src_change_state (GstElement * element, GstStateChange transition)
726 GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
727 GstV4l2Src *v4l2src = GST_V4L2SRC (element);
728 GstV4l2Object *obj = v4l2src->v4l2object;
730 switch (transition) {
731 case GST_STATE_CHANGE_NULL_TO_READY:
732 /* open the device */
733 if (!gst_v4l2_object_open (obj))
734 return GST_STATE_CHANGE_FAILURE;
740 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
742 switch (transition) {
743 case GST_STATE_CHANGE_READY_TO_NULL:
744 /* close the device */
745 if (!gst_v4l2_object_close (obj))
746 return GST_STATE_CHANGE_FAILURE;
748 if (v4l2src->probed_caps) {
749 gst_caps_unref (v4l2src->probed_caps);
750 v4l2src->probed_caps = NULL;
761 gst_v4l2src_fill (GstPushSrc * src, GstBuffer * buf)
763 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
764 GstV4l2Object *obj = v4l2src->v4l2object;
767 GstClockTime abs_time, base_time, timestamp, duration;
771 gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL_CAST (obj->pool), buf);
773 if (G_UNLIKELY (ret != GST_FLOW_OK))
777 timestamp = GST_BUFFER_TIMESTAMP (buf);
778 duration = obj->duration;
780 /* timestamps, LOCK to get clock and base time. */
781 /* FIXME: element clock and base_time is rarely changing */
782 GST_OBJECT_LOCK (v4l2src);
783 if ((clock = GST_ELEMENT_CLOCK (v4l2src))) {
784 /* we have a clock, get base time and ref clock */
785 base_time = GST_ELEMENT (v4l2src)->base_time;
786 gst_object_ref (clock);
788 /* no clock, can't set timestamps */
789 base_time = GST_CLOCK_TIME_NONE;
791 GST_OBJECT_UNLOCK (v4l2src);
793 /* sample pipeline clock */
795 abs_time = gst_clock_get_time (clock);
796 gst_object_unref (clock);
798 abs_time = GST_CLOCK_TIME_NONE;
801 if (timestamp != GST_CLOCK_TIME_NONE) {
805 /* v4l2 specs say to use the system time although many drivers switched to
806 * the more desirable monotonic time. We first try to use the monotonic time
807 * and see how that goes */
808 clock_gettime (CLOCK_MONOTONIC, &now);
809 gstnow = GST_TIMESPEC_TO_TIME (now);
811 if (gstnow < timestamp && (timestamp - gstnow) > (10 * GST_SECOND)) {
814 /* very large diff, fall back to system time */
815 g_get_current_time (&now);
816 gstnow = GST_TIMEVAL_TO_TIME (now);
819 if (gstnow > timestamp) {
820 delay = gstnow - timestamp;
825 GST_DEBUG_OBJECT (v4l2src, "ts: %" GST_TIME_FORMAT " now %" GST_TIME_FORMAT
826 " delay %" GST_TIME_FORMAT, GST_TIME_ARGS (timestamp),
827 GST_TIME_ARGS (gstnow), GST_TIME_ARGS (delay));
829 /* we assume 1 frame latency otherwise */
830 if (GST_CLOCK_TIME_IS_VALID (duration))
836 /* set buffer metadata */
837 GST_BUFFER_OFFSET (buf) = v4l2src->offset++;
838 GST_BUFFER_OFFSET_END (buf) = v4l2src->offset;
840 if (G_LIKELY (abs_time != GST_CLOCK_TIME_NONE)) {
841 /* the time now is the time of the clock minus the base time */
842 timestamp = abs_time - base_time;
844 /* adjust for delay in the device */
845 if (timestamp > delay)
850 timestamp = GST_CLOCK_TIME_NONE;
853 /* activate settings for next frame */
854 if (GST_CLOCK_TIME_IS_VALID (duration)) {
855 v4l2src->ctrl_time += duration;
857 /* this is not very good (as it should be the next timestamp),
858 * still good enough for linear fades (as long as it is not -1)
860 v4l2src->ctrl_time = timestamp;
862 gst_object_sync_values (GST_OBJECT (src), v4l2src->ctrl_time);
864 GST_INFO_OBJECT (src, "sync to %" GST_TIME_FORMAT " out ts %" GST_TIME_FORMAT,
865 GST_TIME_ARGS (v4l2src->ctrl_time), GST_TIME_ARGS (timestamp));
867 GST_BUFFER_TIMESTAMP (buf) = timestamp;
868 GST_BUFFER_DURATION (buf) = duration;
875 GST_DEBUG_OBJECT (src, "error processing buffer %d (%s)", ret,
876 gst_flow_get_name (ret));
882 /* GstURIHandler interface */
884 gst_v4l2src_uri_get_type (GType type)
889 static const gchar *const *
890 gst_v4l2src_uri_get_protocols (GType type)
892 static const gchar *protocols[] = { "v4l2", NULL };
898 gst_v4l2src_uri_get_uri (GstURIHandler * handler)
900 GstV4l2Src *v4l2src = GST_V4L2SRC (handler);
902 if (v4l2src->v4l2object->videodev != NULL) {
903 return g_strdup_printf ("v4l2://%s", v4l2src->v4l2object->videodev);
906 return g_strdup ("v4l2://");
910 gst_v4l2src_uri_set_uri (GstURIHandler * handler, const gchar * uri,
913 GstV4l2Src *v4l2src = GST_V4L2SRC (handler);
914 const gchar *device = DEFAULT_PROP_DEVICE;
916 if (strcmp (uri, "v4l2://") != 0) {
919 g_object_set (v4l2src, "device", device, NULL);
926 gst_v4l2src_uri_handler_init (gpointer g_iface, gpointer iface_data)
928 GstURIHandlerInterface *iface = (GstURIHandlerInterface *) g_iface;
930 iface->get_type = gst_v4l2src_uri_get_type;
931 iface->get_protocols = gst_v4l2src_uri_get_protocols;
932 iface->get_uri = gst_v4l2src_uri_get_uri;
933 iface->set_uri = gst_v4l2src_uri_set_uri;