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 * @fourcc: the fourcc of the format being set
167 * @width: The width of the video
168 * @height: The height of the video
170 * This signal gets emitted before calling the v4l2 VIDIOC_S_FMT ioctl
171 * (set format). This allows for any custom configuration of the device to
172 * happen prior to the format being set.
173 * This is mostly useful for UVC H264 encoding cameras which need the H264
174 * Probe & Commit to happen prior to the normal Probe & Commit.
178 gst_v4l2_signals[SIGNAL_PRE_SET_FORMAT] = g_signal_new ("prepare-format",
179 G_TYPE_FROM_CLASS (klass),
183 NULL, G_TYPE_NONE, 4, G_TYPE_INT, G_TYPE_UINT, G_TYPE_UINT, G_TYPE_UINT);
185 gst_element_class_set_static_metadata (element_class,
186 "Video (video4linux2) Source", "Source/Video",
187 "Reads frames from a Video4Linux2 device",
188 "Edgard Lima <edgard.lima@indt.org.br>, "
189 "Stefan Kost <ensonic@users.sf.net>");
191 gst_element_class_add_pad_template
193 gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
194 gst_v4l2_object_get_all_caps ()));
196 basesrc_class->get_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_get_caps);
197 basesrc_class->set_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_set_caps);
198 basesrc_class->start = GST_DEBUG_FUNCPTR (gst_v4l2src_start);
199 basesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock);
200 basesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock_stop);
201 basesrc_class->stop = GST_DEBUG_FUNCPTR (gst_v4l2src_stop);
202 basesrc_class->query = GST_DEBUG_FUNCPTR (gst_v4l2src_query);
203 basesrc_class->fixate = GST_DEBUG_FUNCPTR (gst_v4l2src_fixate);
204 basesrc_class->event = GST_DEBUG_FUNCPTR (gst_v4l2src_event);
205 basesrc_class->negotiate = GST_DEBUG_FUNCPTR (gst_v4l2src_negotiate);
206 basesrc_class->decide_allocation =
207 GST_DEBUG_FUNCPTR (gst_v4l2src_decide_allocation);
209 pushsrc_class->fill = GST_DEBUG_FUNCPTR (gst_v4l2src_fill);
211 klass->v4l2_class_devices = NULL;
213 GST_DEBUG_CATEGORY_INIT (v4l2src_debug, "v4l2src", 0, "V4L2 source element");
217 gst_v4l2src_init (GstV4l2Src * v4l2src)
219 /* fixme: give an update_fps_function */
220 v4l2src->v4l2object = gst_v4l2_object_new (GST_ELEMENT (v4l2src),
221 V4L2_BUF_TYPE_VIDEO_CAPTURE, DEFAULT_PROP_DEVICE,
222 gst_v4l2_get_input, gst_v4l2_set_input, NULL);
224 gst_base_src_set_format (GST_BASE_SRC (v4l2src), GST_FORMAT_TIME);
225 gst_base_src_set_live (GST_BASE_SRC (v4l2src), TRUE);
229 gst_v4l2src_dispose (GObject * object)
231 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
233 if (v4l2src->probed_caps) {
234 gst_caps_unref (v4l2src->probed_caps);
237 G_OBJECT_CLASS (parent_class)->dispose (object);
242 gst_v4l2src_finalize (GstV4l2Src * v4l2src)
244 gst_v4l2_object_destroy (v4l2src->v4l2object);
246 G_OBJECT_CLASS (parent_class)->finalize ((GObject *) (v4l2src));
251 gst_v4l2src_set_property (GObject * object,
252 guint prop_id, const GValue * value, GParamSpec * pspec)
254 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
256 if (!gst_v4l2_object_set_property_helper (v4l2src->v4l2object,
257 prop_id, value, pspec)) {
260 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
267 gst_v4l2src_get_property (GObject * object,
268 guint prop_id, GValue * value, GParamSpec * pspec)
270 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
272 if (!gst_v4l2_object_get_property_helper (v4l2src->v4l2object,
273 prop_id, value, pspec)) {
276 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
282 /* this function is a bit of a last resort */
284 gst_v4l2src_fixate (GstBaseSrc * basesrc, GstCaps * caps)
286 GstStructure *structure;
289 GST_DEBUG_OBJECT (basesrc, "fixating caps %" GST_PTR_FORMAT, caps);
291 caps = gst_caps_make_writable (caps);
293 for (i = 0; i < gst_caps_get_size (caps); ++i) {
294 structure = gst_caps_get_structure (caps, i);
296 /* We are fixating to a resonable 320x200 resolution
297 and the maximum framerate resolution for that size */
298 gst_structure_fixate_field_nearest_int (structure, "width", 320);
299 gst_structure_fixate_field_nearest_int (structure, "height", 200);
300 gst_structure_fixate_field_nearest_fraction (structure, "framerate",
302 gst_structure_fixate_field (structure, "format");
305 GST_DEBUG_OBJECT (basesrc, "fixated caps %" GST_PTR_FORMAT, caps);
307 caps = GST_BASE_SRC_CLASS (parent_class)->fixate (basesrc, caps);
314 gst_v4l2src_event (GstBaseSrc * src, GstEvent * event)
316 GST_DEBUG_OBJECT (src, "handle event %" GST_PTR_FORMAT, event);
318 switch (GST_EVENT_TYPE (event)) {
319 case GST_EVENT_RECONFIGURE:
320 gst_pad_check_reconfigure (GST_BASE_SRC_PAD (src));
325 return GST_BASE_SRC_CLASS (parent_class)->event (src, event);
330 gst_v4l2src_negotiate (GstBaseSrc * basesrc)
333 GstCaps *caps = NULL;
334 GstCaps *peercaps = NULL;
335 gboolean result = FALSE;
337 /* first see what is possible on our source pad */
338 thiscaps = gst_pad_query_caps (GST_BASE_SRC_PAD (basesrc), NULL);
339 GST_DEBUG_OBJECT (basesrc, "caps of src: %" GST_PTR_FORMAT, thiscaps);
340 LOG_CAPS (basesrc, thiscaps);
342 /* nothing or anything is allowed, we're done */
343 if (thiscaps == NULL || gst_caps_is_any (thiscaps))
346 /* get the peer caps */
347 peercaps = gst_pad_peer_query_caps (GST_BASE_SRC_PAD (basesrc), thiscaps);
348 GST_DEBUG_OBJECT (basesrc, "caps of peer: %" GST_PTR_FORMAT, peercaps);
349 LOG_CAPS (basesrc, peercaps);
350 if (peercaps && !gst_caps_is_any (peercaps)) {
351 GstCaps *icaps = NULL;
354 /* Prefer the first caps we are compatible with that the peer proposed */
355 for (i = 0; i < gst_caps_get_size (peercaps); i++) {
356 /* get intersection */
357 GstCaps *ipcaps = gst_caps_copy_nth (peercaps, i);
359 GST_DEBUG_OBJECT (basesrc, "peer: %" GST_PTR_FORMAT, ipcaps);
360 LOG_CAPS (basesrc, ipcaps);
362 icaps = gst_caps_intersect (thiscaps, ipcaps);
363 gst_caps_unref (ipcaps);
365 if (!gst_caps_is_empty (icaps))
368 gst_caps_unref (icaps);
372 GST_DEBUG_OBJECT (basesrc, "intersect: %" GST_PTR_FORMAT, icaps);
373 LOG_CAPS (basesrc, icaps);
375 /* If there are multiple intersections pick the one with the smallest
376 * resolution strictly bigger then the first peer caps */
377 if (gst_caps_get_size (icaps) > 1) {
378 GstStructure *s = gst_caps_get_structure (peercaps, 0);
381 int width = G_MAXINT, height = G_MAXINT;
383 if (gst_structure_get_int (s, "width", &twidth)
384 && gst_structure_get_int (s, "height", &theight)) {
386 /* Walk the structure backwards to get the first entry of the
387 * smallest resolution bigger (or equal to) the preferred resolution)
389 for (i = gst_caps_get_size (icaps) - 1; i >= 0; i--) {
390 GstStructure *is = gst_caps_get_structure (icaps, i);
393 if (gst_structure_get_int (is, "width", &w)
394 && gst_structure_get_int (is, "height", &h)) {
395 if (w >= twidth && w <= width && h >= theight && h <= height) {
404 caps = gst_caps_copy_nth (icaps, best);
405 gst_caps_unref (icaps);
410 gst_caps_unref (thiscaps);
412 /* no peer or peer have ANY caps, work with our own caps then */
416 gst_caps_unref (peercaps);
418 caps = gst_caps_truncate (caps);
421 if (!gst_caps_is_empty (caps)) {
422 caps = gst_v4l2src_fixate (basesrc, caps);
423 GST_DEBUG_OBJECT (basesrc, "fixated to: %" GST_PTR_FORMAT, caps);
424 LOG_CAPS (basesrc, caps);
426 if (gst_caps_is_any (caps)) {
427 /* hmm, still anything, so element can do anything and
428 * nego is not needed */
430 } else if (gst_caps_is_fixed (caps)) {
431 /* yay, fixed caps, use those then */
432 result = gst_base_src_set_caps (basesrc, caps);
435 gst_caps_unref (caps);
441 GST_DEBUG_OBJECT (basesrc, "no negotiation needed");
443 gst_caps_unref (thiscaps);
449 gst_v4l2src_get_caps (GstBaseSrc * src, GstCaps * filter)
457 v4l2src = GST_V4L2SRC (src);
458 obj = v4l2src->v4l2object;
460 if (!GST_V4L2_IS_OPEN (obj)) {
461 return gst_pad_get_pad_template_caps (GST_BASE_SRC_PAD (v4l2src));
464 if (v4l2src->probed_caps)
465 return gst_caps_ref (v4l2src->probed_caps);
467 formats = gst_v4l2_object_get_format_list (obj);
469 ret = gst_caps_new_empty ();
471 for (walk = formats; walk; walk = walk->next) {
472 struct v4l2_fmtdesc *format;
473 GstStructure *template;
475 format = (struct v4l2_fmtdesc *) walk->data;
477 template = gst_v4l2_object_v4l2fourcc_to_structure (format->pixelformat);
483 gst_v4l2_object_probe_caps_for_format (obj,
484 format->pixelformat, template);
486 gst_caps_append (ret, tmp);
488 gst_structure_free (template);
490 GST_DEBUG_OBJECT (v4l2src, "unknown format %u", format->pixelformat);
494 v4l2src->probed_caps = gst_caps_ref (ret);
496 GST_INFO_OBJECT (v4l2src, "probed caps: %" GST_PTR_FORMAT, ret);
502 gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps)
507 v4l2src = GST_V4L2SRC (src);
508 obj = v4l2src->v4l2object;
510 /* make sure we stop capturing and dealloc buffers */
511 if (!gst_v4l2_object_stop (obj))
514 if (!gst_v4l2_object_set_format (obj, caps))
515 /* error already posted */
522 gst_v4l2src_decide_allocation (GstBaseSrc * bsrc, GstQuery * query)
527 guint size, min, max;
530 src = GST_V4L2SRC (bsrc);
531 obj = src->v4l2object;
533 if (gst_query_get_n_allocation_pools (query) > 0) {
534 gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);
543 GST_DEBUG_OBJECT (src, "allocation: size:%u min:%u max:%u pool:%"
544 GST_PTR_FORMAT, size, min, max, pool);
547 /* if there is a min-buffers suggestion, use it. We add 1 because we need 1
548 * buffer extra to capture while the other two buffers are downstream */
558 /* no downstream pool, use our own then */
559 GST_DEBUG_OBJECT (src,
560 "read/write mode: no downstream pool, using our own");
561 pool = GST_BUFFER_POOL_CAST (obj->pool);
562 size = obj->sizeimage;
564 /* in READ/WRITE mode, prefer a downstream pool because our own pool
565 * doesn't help much, we have to write to it as well */
566 GST_DEBUG_OBJECT (src, "read/write mode: using downstream pool");
567 /* use the bigest size, when we use our own pool we can't really do any
568 * other size than what the hardware gives us but for downstream pools
570 size = MAX (size, obj->sizeimage);
573 case GST_V4L2_IO_MMAP:
574 case GST_V4L2_IO_USERPTR:
575 /* in streaming mode, prefer our own pool */
576 pool = GST_BUFFER_POOL_CAST (obj->pool);
577 size = obj->sizeimage;
578 GST_DEBUG_OBJECT (src,
579 "streaming mode: using our own pool %" GST_PTR_FORMAT, pool);
581 case GST_V4L2_IO_AUTO:
583 GST_WARNING_OBJECT (src, "unhandled mode");
588 GstStructure *config;
591 config = gst_buffer_pool_get_config (pool);
592 gst_buffer_pool_config_get_params (config, &caps, NULL, NULL, NULL);
593 gst_buffer_pool_config_set_params (config, caps, size, min, max);
595 /* if downstream supports video metadata, add this to the pool config */
596 if (gst_query_find_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL)) {
597 GST_DEBUG_OBJECT (pool, "activate Video Meta");
598 gst_buffer_pool_config_add_option (config,
599 GST_BUFFER_POOL_OPTION_VIDEO_META);
602 gst_buffer_pool_set_config (pool, config);
606 gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
608 gst_query_add_allocation_pool (query, pool, size, min, max);
610 return GST_BASE_SRC_CLASS (parent_class)->decide_allocation (bsrc, query);
614 gst_v4l2src_query (GstBaseSrc * bsrc, GstQuery * query)
618 gboolean res = FALSE;
620 src = GST_V4L2SRC (bsrc);
621 obj = src->v4l2object;
623 switch (GST_QUERY_TYPE (query)) {
624 case GST_QUERY_LATENCY:{
625 GstClockTime min_latency, max_latency;
626 guint32 fps_n, fps_d;
627 guint num_buffers = 0;
629 /* device must be open */
630 if (!GST_V4L2_IS_OPEN (obj)) {
631 GST_WARNING_OBJECT (src,
632 "Can't give latency since device isn't open !");
636 fps_n = GST_V4L2_FPS_N (obj);
637 fps_d = GST_V4L2_FPS_D (obj);
639 /* we must have a framerate */
640 if (fps_n <= 0 || fps_d <= 0) {
641 GST_WARNING_OBJECT (src,
642 "Can't give latency since framerate isn't fixated !");
646 /* min latency is the time to capture one frame */
647 min_latency = gst_util_uint64_scale_int (GST_SECOND, fps_d, fps_n);
649 /* max latency is total duration of the frame buffer */
650 if (obj->pool != NULL)
651 num_buffers = GST_V4L2_BUFFER_POOL_CAST (obj->pool)->num_buffers;
653 if (num_buffers == 0)
656 max_latency = num_buffers * min_latency;
658 GST_DEBUG_OBJECT (bsrc,
659 "report latency min %" GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
660 GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));
662 /* we are always live, the min latency is 1 frame and the max latency is
663 * the complete buffer of frames. */
664 gst_query_set_latency (query, TRUE, min_latency, max_latency);
670 res = GST_BASE_SRC_CLASS (parent_class)->query (bsrc, query);
679 /* start and stop are not symmetric -- start will open the device, but not start
680 * capture. it's setcaps that will start capture, which is called via basesrc's
681 * negotiate method. stop will both stop capture and close the device.
684 gst_v4l2src_start (GstBaseSrc * src)
686 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
690 /* activate settings for first frame */
691 v4l2src->ctrl_time = 0;
692 gst_object_sync_values (GST_OBJECT (src), v4l2src->ctrl_time);
698 gst_v4l2src_unlock (GstBaseSrc * src)
700 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
701 return gst_v4l2_object_unlock (v4l2src->v4l2object);
705 gst_v4l2src_unlock_stop (GstBaseSrc * src)
707 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
708 return gst_v4l2_object_unlock_stop (v4l2src->v4l2object);
712 gst_v4l2src_stop (GstBaseSrc * src)
714 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
715 GstV4l2Object *obj = v4l2src->v4l2object;
717 if (GST_V4L2_IS_ACTIVE (obj)) {
718 if (!gst_v4l2_object_stop (obj))
724 static GstStateChangeReturn
725 gst_v4l2src_change_state (GstElement * element, GstStateChange transition)
727 GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
728 GstV4l2Src *v4l2src = GST_V4L2SRC (element);
729 GstV4l2Object *obj = v4l2src->v4l2object;
731 switch (transition) {
732 case GST_STATE_CHANGE_NULL_TO_READY:
733 /* open the device */
734 if (!gst_v4l2_object_open (obj))
735 return GST_STATE_CHANGE_FAILURE;
741 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
743 switch (transition) {
744 case GST_STATE_CHANGE_READY_TO_NULL:
745 /* close the device */
746 if (!gst_v4l2_object_close (obj))
747 return GST_STATE_CHANGE_FAILURE;
749 if (v4l2src->probed_caps) {
750 gst_caps_unref (v4l2src->probed_caps);
751 v4l2src->probed_caps = NULL;
762 gst_v4l2src_fill (GstPushSrc * src, GstBuffer * buf)
764 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
765 GstV4l2Object *obj = v4l2src->v4l2object;
768 GstClockTime abs_time, base_time, timestamp, duration;
772 gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL_CAST (obj->pool), buf);
774 if (G_UNLIKELY (ret != GST_FLOW_OK))
778 timestamp = GST_BUFFER_TIMESTAMP (buf);
779 duration = obj->duration;
781 /* timestamps, LOCK to get clock and base time. */
782 /* FIXME: element clock and base_time is rarely changing */
783 GST_OBJECT_LOCK (v4l2src);
784 if ((clock = GST_ELEMENT_CLOCK (v4l2src))) {
785 /* we have a clock, get base time and ref clock */
786 base_time = GST_ELEMENT (v4l2src)->base_time;
787 gst_object_ref (clock);
789 /* no clock, can't set timestamps */
790 base_time = GST_CLOCK_TIME_NONE;
792 GST_OBJECT_UNLOCK (v4l2src);
794 /* sample pipeline clock */
796 abs_time = gst_clock_get_time (clock);
797 gst_object_unref (clock);
799 abs_time = GST_CLOCK_TIME_NONE;
802 if (timestamp != GST_CLOCK_TIME_NONE) {
806 /* v4l2 specs say to use the system time although many drivers switched to
807 * the more desirable monotonic time. We first try to use the monotonic time
808 * and see how that goes */
809 clock_gettime (CLOCK_MONOTONIC, &now);
810 gstnow = GST_TIMESPEC_TO_TIME (now);
812 if (gstnow < timestamp && (timestamp - gstnow) > (10 * GST_SECOND)) {
815 /* very large diff, fall back to system time */
816 g_get_current_time (&now);
817 gstnow = GST_TIMEVAL_TO_TIME (now);
820 if (gstnow > timestamp) {
821 delay = gstnow - timestamp;
826 GST_DEBUG_OBJECT (v4l2src, "ts: %" GST_TIME_FORMAT " now %" GST_TIME_FORMAT
827 " delay %" GST_TIME_FORMAT, GST_TIME_ARGS (timestamp),
828 GST_TIME_ARGS (gstnow), GST_TIME_ARGS (delay));
830 /* we assume 1 frame latency otherwise */
831 if (GST_CLOCK_TIME_IS_VALID (duration))
837 /* set buffer metadata */
838 GST_BUFFER_OFFSET (buf) = v4l2src->offset++;
839 GST_BUFFER_OFFSET_END (buf) = v4l2src->offset;
841 if (G_LIKELY (abs_time != GST_CLOCK_TIME_NONE)) {
842 /* the time now is the time of the clock minus the base time */
843 timestamp = abs_time - base_time;
845 /* adjust for delay in the device */
846 if (timestamp > delay)
851 timestamp = GST_CLOCK_TIME_NONE;
854 /* activate settings for next frame */
855 if (GST_CLOCK_TIME_IS_VALID (duration)) {
856 v4l2src->ctrl_time += duration;
858 /* this is not very good (as it should be the next timestamp),
859 * still good enough for linear fades (as long as it is not -1)
861 v4l2src->ctrl_time = timestamp;
863 gst_object_sync_values (GST_OBJECT (src), v4l2src->ctrl_time);
865 GST_INFO_OBJECT (src, "sync to %" GST_TIME_FORMAT " out ts %" GST_TIME_FORMAT,
866 GST_TIME_ARGS (v4l2src->ctrl_time), GST_TIME_ARGS (timestamp));
868 GST_BUFFER_TIMESTAMP (buf) = timestamp;
869 GST_BUFFER_DURATION (buf) = duration;
876 GST_DEBUG_OBJECT (src, "error processing buffer %d (%s)", ret,
877 gst_flow_get_name (ret));
883 /* GstURIHandler interface */
885 gst_v4l2src_uri_get_type (GType type)
890 static const gchar *const *
891 gst_v4l2src_uri_get_protocols (GType type)
893 static const gchar *protocols[] = { "v4l2", NULL };
899 gst_v4l2src_uri_get_uri (GstURIHandler * handler)
901 GstV4l2Src *v4l2src = GST_V4L2SRC (handler);
903 if (v4l2src->v4l2object->videodev != NULL) {
904 return g_strdup_printf ("v4l2://%s", v4l2src->v4l2object->videodev);
907 return g_strdup ("v4l2://");
911 gst_v4l2src_uri_set_uri (GstURIHandler * handler, const gchar * uri,
914 GstV4l2Src *v4l2src = GST_V4L2SRC (handler);
915 const gchar *device = DEFAULT_PROP_DEVICE;
917 if (strcmp (uri, "v4l2://") != 0) {
920 g_object_set (v4l2src, "device", device, NULL);
927 gst_v4l2src_uri_handler_init (gpointer g_iface, gpointer iface_data)
929 GstURIHandlerInterface *iface = (GstURIHandlerInterface *) g_iface;
931 iface->get_type = gst_v4l2src_uri_get_type;
932 iface->get_protocols = gst_v4l2src_uri_get_protocols;
933 iface->get_uri = gst_v4l2src_uri_get_uri;
934 iface->set_uri = gst_v4l2src_uri_set_uri;