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., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, 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 v4l2src ! xvimagesink
34 * ]| This pipeline shows the video captured from /dev/video0 tv card and for
37 * gst-launch 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 PROP_DEF_ALWAYS_COPY TRUE
71 #define PROP_DEF_DECIMATE 1
73 #define DEFAULT_PROP_DEVICE "/dev/video0"
78 V4L2_STD_OBJECT_PROPS,
83 GST_IMPLEMENT_V4L2_COLOR_BALANCE_METHODS (GstV4l2Src, gst_v4l2src);
84 GST_IMPLEMENT_V4L2_TUNER_METHODS (GstV4l2Src, gst_v4l2src);
86 GST_IMPLEMENT_V4L2_XOVERLAY_METHODS (GstV4l2Src, gst_v4l2src);
88 GST_IMPLEMENT_V4L2_VIDORIENT_METHODS (GstV4l2Src, gst_v4l2src);
90 static void gst_v4l2src_uri_handler_init (gpointer g_iface,
93 #define gst_v4l2src_parent_class parent_class
94 G_DEFINE_TYPE_WITH_CODE (GstV4l2Src, gst_v4l2src, GST_TYPE_PUSH_SRC,
95 G_IMPLEMENT_INTERFACE (GST_TYPE_URI_HANDLER, gst_v4l2src_uri_handler_init);
96 G_IMPLEMENT_INTERFACE (GST_TYPE_TUNER, gst_v4l2src_tuner_interface_init);
98 /* FIXME: does GstXOverlay for v4l2src make sense in a GStreamer context? */
99 G_IMPLEMENT_INTERFACE (GST_TYPE_X_OVERLAY,
100 gst_v4l2src_xoverlay_interface_init);
102 G_IMPLEMENT_INTERFACE (GST_TYPE_COLOR_BALANCE,
103 gst_v4l2src_color_balance_interface_init);
104 G_IMPLEMENT_INTERFACE (GST_TYPE_VIDEO_ORIENTATION,
105 gst_v4l2src_video_orientation_interface_init));
107 static void gst_v4l2src_dispose (GObject * object);
108 static void gst_v4l2src_finalize (GstV4l2Src * v4l2src);
110 /* element methods */
111 static GstStateChangeReturn gst_v4l2src_change_state (GstElement * element,
112 GstStateChange transition);
114 /* basesrc methods */
115 static gboolean gst_v4l2src_start (GstBaseSrc * src);
116 static gboolean gst_v4l2src_unlock (GstBaseSrc * src);
117 static gboolean gst_v4l2src_unlock_stop (GstBaseSrc * src);
118 static gboolean gst_v4l2src_stop (GstBaseSrc * src);
119 static gboolean gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps);
120 static GstCaps *gst_v4l2src_get_caps (GstBaseSrc * src, GstCaps * filter);
121 static gboolean gst_v4l2src_query (GstBaseSrc * bsrc, GstQuery * query);
122 static gboolean gst_v4l2src_decide_allocation (GstBaseSrc * src,
124 static GstFlowReturn gst_v4l2src_fill (GstPushSrc * src, GstBuffer * out);
125 static GstCaps *gst_v4l2src_fixate (GstBaseSrc * basesrc, GstCaps * caps);
126 static gboolean gst_v4l2src_negotiate (GstBaseSrc * basesrc);
128 static void gst_v4l2src_set_property (GObject * object, guint prop_id,
129 const GValue * value, GParamSpec * pspec);
130 static void gst_v4l2src_get_property (GObject * object, guint prop_id,
131 GValue * value, GParamSpec * pspec);
134 gst_v4l2src_class_init (GstV4l2SrcClass * klass)
136 GObjectClass *gobject_class;
137 GstElementClass *element_class;
138 GstBaseSrcClass *basesrc_class;
139 GstPushSrcClass *pushsrc_class;
141 gobject_class = G_OBJECT_CLASS (klass);
142 element_class = GST_ELEMENT_CLASS (klass);
143 basesrc_class = GST_BASE_SRC_CLASS (klass);
144 pushsrc_class = GST_PUSH_SRC_CLASS (klass);
146 gobject_class->dispose = gst_v4l2src_dispose;
147 gobject_class->finalize = (GObjectFinalizeFunc) gst_v4l2src_finalize;
148 gobject_class->set_property = gst_v4l2src_set_property;
149 gobject_class->get_property = gst_v4l2src_get_property;
151 element_class->change_state = gst_v4l2src_change_state;
153 gst_v4l2_object_install_properties_helper (gobject_class,
154 DEFAULT_PROP_DEVICE);
155 g_object_class_install_property (gobject_class, PROP_ALWAYS_COPY,
156 g_param_spec_boolean ("always-copy", "Always Copy",
157 "If the buffer will or not be used directly from mmap",
158 PROP_DEF_ALWAYS_COPY, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
160 * GstV4l2Src:decimate
162 * Only use every nth frame
166 g_object_class_install_property (gobject_class, PROP_DECIMATE,
167 g_param_spec_int ("decimate", "Decimate",
168 "Only use every nth frame", 1, G_MAXINT,
169 PROP_DEF_DECIMATE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
171 gst_element_class_set_details_simple (element_class,
172 "Video (video4linux2) Source", "Source/Video",
173 "Reads frames from a Video4Linux2 device",
174 "Edgard Lima <edgard.lima@indt.org.br>, "
175 "Stefan Kost <ensonic@users.sf.net>");
177 gst_element_class_add_pad_template
179 gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
180 gst_v4l2_object_get_all_caps ()));
182 basesrc_class->get_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_get_caps);
183 basesrc_class->set_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_set_caps);
184 basesrc_class->start = GST_DEBUG_FUNCPTR (gst_v4l2src_start);
185 basesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock);
186 basesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock_stop);
187 basesrc_class->stop = GST_DEBUG_FUNCPTR (gst_v4l2src_stop);
188 basesrc_class->query = GST_DEBUG_FUNCPTR (gst_v4l2src_query);
189 basesrc_class->fixate = GST_DEBUG_FUNCPTR (gst_v4l2src_fixate);
190 basesrc_class->negotiate = GST_DEBUG_FUNCPTR (gst_v4l2src_negotiate);
191 basesrc_class->decide_allocation =
192 GST_DEBUG_FUNCPTR (gst_v4l2src_decide_allocation);
194 pushsrc_class->fill = GST_DEBUG_FUNCPTR (gst_v4l2src_fill);
196 klass->v4l2_class_devices = NULL;
198 GST_DEBUG_CATEGORY_INIT (v4l2src_debug, "v4l2src", 0, "V4L2 source element");
202 gst_v4l2src_init (GstV4l2Src * v4l2src)
204 /* fixme: give an update_fps_function */
205 v4l2src->v4l2object = gst_v4l2_object_new (GST_ELEMENT (v4l2src),
206 V4L2_BUF_TYPE_VIDEO_CAPTURE, DEFAULT_PROP_DEVICE,
207 gst_v4l2_get_input, gst_v4l2_set_input, NULL);
209 v4l2src->v4l2object->always_copy = PROP_DEF_ALWAYS_COPY;
210 v4l2src->decimate = PROP_DEF_DECIMATE;
212 gst_base_src_set_format (GST_BASE_SRC (v4l2src), GST_FORMAT_TIME);
213 gst_base_src_set_live (GST_BASE_SRC (v4l2src), TRUE);
217 gst_v4l2src_dispose (GObject * object)
219 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
221 if (v4l2src->probed_caps) {
222 gst_caps_unref (v4l2src->probed_caps);
225 G_OBJECT_CLASS (parent_class)->dispose (object);
230 gst_v4l2src_finalize (GstV4l2Src * v4l2src)
232 gst_v4l2_object_destroy (v4l2src->v4l2object);
234 G_OBJECT_CLASS (parent_class)->finalize ((GObject *) (v4l2src));
239 gst_v4l2src_set_property (GObject * object,
240 guint prop_id, const GValue * value, GParamSpec * pspec)
242 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
244 if (!gst_v4l2_object_set_property_helper (v4l2src->v4l2object,
245 prop_id, value, pspec)) {
247 case PROP_ALWAYS_COPY:
248 v4l2src->v4l2object->always_copy = g_value_get_boolean (value);
251 v4l2src->decimate = g_value_get_int (value);
254 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
261 gst_v4l2src_get_property (GObject * object,
262 guint prop_id, GValue * value, GParamSpec * pspec)
264 GstV4l2Src *v4l2src = GST_V4L2SRC (object);
266 if (!gst_v4l2_object_get_property_helper (v4l2src->v4l2object,
267 prop_id, value, pspec)) {
269 case PROP_ALWAYS_COPY:
270 g_value_set_boolean (value, v4l2src->v4l2object->always_copy);
273 g_value_set_int (value, v4l2src->decimate);
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_negotiate (GstBaseSrc * basesrc)
317 GstCaps *caps = NULL;
318 GstCaps *peercaps = NULL;
319 gboolean result = FALSE;
321 /* first see what is possible on our source pad */
322 thiscaps = gst_pad_query_caps (GST_BASE_SRC_PAD (basesrc), NULL);
323 GST_DEBUG_OBJECT (basesrc, "caps of src: %" GST_PTR_FORMAT, thiscaps);
324 LOG_CAPS (basesrc, thiscaps);
326 /* nothing or anything is allowed, we're done */
327 if (thiscaps == NULL || gst_caps_is_any (thiscaps))
330 /* get the peer caps */
331 peercaps = gst_pad_peer_query_caps (GST_BASE_SRC_PAD (basesrc), thiscaps);
332 GST_DEBUG_OBJECT (basesrc, "caps of peer: %" GST_PTR_FORMAT, peercaps);
333 LOG_CAPS (basesrc, peercaps);
334 if (peercaps && !gst_caps_is_any (peercaps)) {
335 GstCaps *icaps = NULL;
338 /* Prefer the first caps we are compatible with that the peer proposed */
339 for (i = 0; i < gst_caps_get_size (peercaps); i++) {
340 /* get intersection */
341 GstCaps *ipcaps = gst_caps_copy_nth (peercaps, i);
343 GST_DEBUG_OBJECT (basesrc, "peer: %" GST_PTR_FORMAT, ipcaps);
344 LOG_CAPS (basesrc, ipcaps);
346 icaps = gst_caps_intersect (thiscaps, ipcaps);
347 gst_caps_unref (ipcaps);
349 if (!gst_caps_is_empty (icaps))
352 gst_caps_unref (icaps);
356 GST_DEBUG_OBJECT (basesrc, "intersect: %" GST_PTR_FORMAT, icaps);
357 LOG_CAPS (basesrc, icaps);
359 /* If there are multiple intersections pick the one with the smallest
360 * resolution strictly bigger then the first peer caps */
361 if (gst_caps_get_size (icaps) > 1) {
362 GstStructure *s = gst_caps_get_structure (peercaps, 0);
365 int width = G_MAXINT, height = G_MAXINT;
367 if (gst_structure_get_int (s, "width", &twidth)
368 && gst_structure_get_int (s, "height", &theight)) {
370 /* Walk the structure backwards to get the first entry of the
371 * smallest resolution bigger (or equal to) the preferred resolution)
373 for (i = gst_caps_get_size (icaps) - 1; i >= 0; i--) {
374 GstStructure *is = gst_caps_get_structure (icaps, i);
377 if (gst_structure_get_int (is, "width", &w)
378 && gst_structure_get_int (is, "height", &h)) {
379 if (w >= twidth && w <= width && h >= theight && h <= height) {
388 caps = gst_caps_copy_nth (icaps, best);
389 gst_caps_unref (icaps);
394 gst_caps_unref (thiscaps);
396 /* no peer or peer have ANY caps, work with our own caps then */
400 gst_caps_unref (peercaps);
402 caps = gst_caps_truncate (caps);
405 if (!gst_caps_is_empty (caps)) {
406 caps = gst_v4l2src_fixate (basesrc, caps);
407 GST_DEBUG_OBJECT (basesrc, "fixated to: %" GST_PTR_FORMAT, caps);
408 LOG_CAPS (basesrc, caps);
410 if (gst_caps_is_any (caps)) {
411 /* hmm, still anything, so element can do anything and
412 * nego is not needed */
414 } else if (gst_caps_is_fixed (caps)) {
415 /* yay, fixed caps, use those then */
416 result = gst_base_src_set_caps (basesrc, caps);
419 gst_caps_unref (caps);
425 GST_DEBUG_OBJECT (basesrc, "no negotiation needed");
427 gst_caps_unref (thiscaps);
433 gst_v4l2src_get_caps (GstBaseSrc * src, GstCaps * filter)
441 v4l2src = GST_V4L2SRC (src);
442 obj = v4l2src->v4l2object;
444 if (!GST_V4L2_IS_OPEN (obj)) {
447 gst_caps_copy (gst_pad_get_pad_template_caps (GST_BASE_SRC_PAD
451 if (v4l2src->probed_caps)
452 return gst_caps_ref (v4l2src->probed_caps);
454 formats = gst_v4l2_object_get_format_list (obj);
456 ret = gst_caps_new_empty ();
458 for (walk = formats; walk; walk = walk->next) {
459 struct v4l2_fmtdesc *format;
460 GstStructure *template;
462 format = (struct v4l2_fmtdesc *) walk->data;
464 template = gst_v4l2_object_v4l2fourcc_to_structure (format->pixelformat);
470 gst_v4l2_object_probe_caps_for_format (obj,
471 format->pixelformat, template);
473 gst_caps_append (ret, tmp);
475 gst_structure_free (template);
477 GST_DEBUG_OBJECT (v4l2src, "unknown format %u", format->pixelformat);
481 v4l2src->probed_caps = gst_caps_ref (ret);
483 GST_INFO_OBJECT (v4l2src, "probed caps: %" GST_PTR_FORMAT, ret);
489 gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps)
494 v4l2src = GST_V4L2SRC (src);
495 obj = v4l2src->v4l2object;
497 /* make sure we stop capturing and dealloc buffers */
498 if (!gst_v4l2_object_stop (obj))
501 if (!gst_v4l2_object_set_format (obj, caps))
502 /* error already posted */
509 gst_v4l2src_decide_allocation (GstBaseSrc * bsrc, GstQuery * query)
514 guint size, min, max;
517 src = GST_V4L2SRC (bsrc);
518 obj = src->v4l2object;
520 if (gst_query_get_n_allocation_pools (query) > 0) {
521 gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);
530 GST_DEBUG_OBJECT (src, "allocation: size:%u min:%u max:%u pool:%"
531 GST_PTR_FORMAT, size, min, max, pool);
534 /* if there is a min-buffers suggestion, use it. We add 1 because we need 1
535 * buffer extra to capture while the other two buffers are downstream */
545 /* no downstream pool, use our own then */
546 GST_DEBUG_OBJECT (src,
547 "read/write mode: no downstream pool, using our own");
548 pool = GST_BUFFER_POOL_CAST (obj->pool);
549 size = obj->sizeimage;
551 /* in READ/WRITE mode, prefer a downstream pool because our own pool
552 * doesn't help much, we have to write to it as well */
553 GST_DEBUG_OBJECT (src, "read/write mode: using downstream pool");
554 /* use the bigest size, when we use our own pool we can't really do any
555 * other size than what the hardware gives us but for downstream pools
557 size = MAX (size, obj->sizeimage);
560 case GST_V4L2_IO_MMAP:
561 case GST_V4L2_IO_USERPTR:
562 /* in streaming mode, prefer our own pool */
563 pool = GST_BUFFER_POOL_CAST (obj->pool);
564 size = obj->sizeimage;
565 GST_DEBUG_OBJECT (src,
566 "streaming mode: using our own pool %" GST_PTR_FORMAT, pool);
568 case GST_V4L2_IO_AUTO:
570 GST_WARNING_OBJECT (src, "unhandled mode");
575 GstStructure *config;
578 config = gst_buffer_pool_get_config (pool);
579 gst_buffer_pool_config_get_params (config, &caps, NULL, NULL, NULL);
580 gst_buffer_pool_config_set_params (config, caps, size, min, max);
582 /* if downstream supports video metadata, add this to the pool config */
583 if (gst_query_has_allocation_meta (query, GST_VIDEO_META_API_TYPE))
584 gst_buffer_pool_config_add_option (config,
585 GST_BUFFER_POOL_OPTION_VIDEO_META);
587 gst_buffer_pool_set_config (pool, config);
591 gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
593 gst_query_add_allocation_pool (query, pool, size, min, max);
599 gst_v4l2src_query (GstBaseSrc * bsrc, GstQuery * query)
603 gboolean res = FALSE;
605 src = GST_V4L2SRC (bsrc);
606 obj = src->v4l2object;
608 switch (GST_QUERY_TYPE (query)) {
609 case GST_QUERY_LATENCY:{
610 GstClockTime min_latency, max_latency;
611 guint32 fps_n, fps_d;
614 /* device must be open */
615 if (!GST_V4L2_IS_OPEN (obj)) {
616 GST_WARNING_OBJECT (src,
617 "Can't give latency since device isn't open !");
621 fps_n = GST_V4L2_FPS_N (obj);
622 fps_d = GST_V4L2_FPS_D (obj);
624 /* we must have a framerate */
625 if (fps_n <= 0 || fps_d <= 0) {
626 GST_WARNING_OBJECT (src,
627 "Can't give latency since framerate isn't fixated !");
631 /* min latency is the time to capture one frame */
632 min_latency = gst_util_uint64_scale_int (GST_SECOND, fps_d, fps_n);
634 /* max latency is total duration of the frame buffer */
635 max_buffers = GST_V4L2_BUFFER_POOL_CAST (obj->pool)->max_buffers;
637 if (max_buffers == 0)
640 max_latency = max_buffers * min_latency;
642 GST_DEBUG_OBJECT (bsrc,
643 "report latency min %" GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
644 GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));
646 /* we are always live, the min latency is 1 frame and the max latency is
647 * the complete buffer of frames. */
648 gst_query_set_latency (query, TRUE, min_latency, max_latency);
654 res = GST_BASE_SRC_CLASS (parent_class)->query (bsrc, query);
663 /* start and stop are not symmetric -- start will open the device, but not start
664 * capture. it's setcaps that will start capture, which is called via basesrc's
665 * negotiate method. stop will both stop capture and close the device.
668 gst_v4l2src_start (GstBaseSrc * src)
670 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
674 /* activate settings for first frame */
675 v4l2src->ctrl_time = 0;
676 gst_object_sync_values (GST_OBJECT (src), v4l2src->ctrl_time);
682 gst_v4l2src_unlock (GstBaseSrc * src)
684 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
685 return gst_v4l2_object_unlock (v4l2src->v4l2object);
689 gst_v4l2src_unlock_stop (GstBaseSrc * src)
691 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
692 return gst_v4l2_object_unlock_stop (v4l2src->v4l2object);
696 gst_v4l2src_stop (GstBaseSrc * src)
698 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
699 GstV4l2Object *obj = v4l2src->v4l2object;
701 if (GST_V4L2_IS_ACTIVE (obj)) {
702 if (!gst_v4l2_object_stop (obj))
708 static GstStateChangeReturn
709 gst_v4l2src_change_state (GstElement * element, GstStateChange transition)
711 GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
712 GstV4l2Src *v4l2src = GST_V4L2SRC (element);
713 GstV4l2Object *obj = v4l2src->v4l2object;
715 switch (transition) {
716 case GST_STATE_CHANGE_NULL_TO_READY:
717 /* open the device */
718 if (!gst_v4l2_object_open (obj))
719 return GST_STATE_CHANGE_FAILURE;
725 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
727 switch (transition) {
728 case GST_STATE_CHANGE_READY_TO_NULL:
729 /* close the device */
730 if (!gst_v4l2_object_close (obj))
731 return GST_STATE_CHANGE_FAILURE;
733 if (v4l2src->probed_caps) {
734 gst_caps_unref (v4l2src->probed_caps);
735 v4l2src->probed_caps = NULL;
746 gst_v4l2src_fill (GstPushSrc * src, GstBuffer * buf)
748 GstV4l2Src *v4l2src = GST_V4L2SRC (src);
749 GstV4l2Object *obj = v4l2src->v4l2object;
752 GstClockTime timestamp, duration;
756 /* decimate, just capture and throw away frames */
757 for (i = 0; i < v4l2src->decimate - 1; i++) {
758 ret = gst_v4l2_buffer_pool_process (obj, buf);
759 if (ret != GST_FLOW_OK) {
762 gst_buffer_unref (*buf);
767 gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL_CAST (obj->pool), buf);
769 if (G_UNLIKELY (ret != GST_FLOW_OK))
772 /* set buffer metadata */
773 GST_BUFFER_OFFSET (buf) = v4l2src->offset++;
774 GST_BUFFER_OFFSET_END (buf) = v4l2src->offset;
776 /* timestamps, LOCK to get clock and base time. */
777 /* FIXME: element clock and base_time is rarely changing */
778 GST_OBJECT_LOCK (v4l2src);
779 if ((clock = GST_ELEMENT_CLOCK (v4l2src))) {
780 /* we have a clock, get base time and ref clock */
781 timestamp = GST_ELEMENT (v4l2src)->base_time;
782 gst_object_ref (clock);
784 /* no clock, can't set timestamps */
785 timestamp = GST_CLOCK_TIME_NONE;
787 GST_OBJECT_UNLOCK (v4l2src);
789 duration = obj->duration;
791 if (G_LIKELY (clock)) {
792 /* the time now is the time of the clock minus the base time */
793 timestamp = gst_clock_get_time (clock) - timestamp;
794 gst_object_unref (clock);
796 /* if we have a framerate adjust timestamp for frame latency */
797 if (GST_CLOCK_TIME_IS_VALID (duration)) {
798 if (timestamp > duration)
799 timestamp -= duration;
805 /* activate settings for next frame */
806 if (GST_CLOCK_TIME_IS_VALID (duration)) {
807 v4l2src->ctrl_time += duration;
809 /* this is not very good (as it should be the next timestamp),
810 * still good enough for linear fades (as long as it is not -1)
812 v4l2src->ctrl_time = timestamp;
814 gst_object_sync_values (GST_OBJECT (src), v4l2src->ctrl_time);
815 GST_INFO_OBJECT (src, "sync to %" GST_TIME_FORMAT,
816 GST_TIME_ARGS (v4l2src->ctrl_time));
818 /* FIXME: use the timestamp from the buffer itself! */
819 GST_BUFFER_TIMESTAMP (buf) = timestamp;
820 GST_BUFFER_DURATION (buf) = duration;
827 GST_ERROR_OBJECT (src, "error processing buffer");
833 /* GstURIHandler interface */
835 gst_v4l2src_uri_get_type (GType type)
840 static const gchar *const *
841 gst_v4l2src_uri_get_protocols (GType type)
843 static const gchar *protocols[] = { "v4l2", NULL };
849 gst_v4l2src_uri_get_uri (GstURIHandler * handler)
851 GstV4l2Src *v4l2src = GST_V4L2SRC (handler);
853 if (v4l2src->v4l2object->videodev != NULL) {
854 return g_strdup_printf ("v4l2://%s", v4l2src->v4l2object->videodev);
857 return g_strdup ("v4l2://");
861 gst_v4l2src_uri_set_uri (GstURIHandler * handler, const gchar * uri,
864 GstV4l2Src *v4l2src = GST_V4L2SRC (handler);
865 const gchar *device = DEFAULT_PROP_DEVICE;
867 if (strcmp (uri, "v4l2://") != 0) {
870 g_object_set (v4l2src, "device", device, NULL);
877 gst_v4l2src_uri_handler_init (gpointer g_iface, gpointer iface_data)
879 GstURIHandlerInterface *iface = (GstURIHandlerInterface *) g_iface;
881 iface->get_type = gst_v4l2src_uri_get_type;
882 iface->get_protocols = gst_v4l2src_uri_get_protocols;
883 iface->get_uri = gst_v4l2src_uri_get_uri;
884 iface->set_uri = gst_v4l2src_uri_set_uri;