3 * Copyright (C) 2009 Texas Instruments, Inc - http://www.ti.com/
5 * Description: V4L2 sink element
6 * Created on: Jul 2, 2009
7 * Author: Rob Clark <rob@ti.com>
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Library General Public
11 * License as published by the Free Software Foundation; either
12 * version 2 of the License, or (at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Library General Public License for more details.
19 * You should have received a copy of the GNU Library General Public
20 * License along with this library; if not, write to the
21 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
22 * Boston, MA 02111-1307, USA.
26 * SECTION:element-v4l2sink
28 * v4l2sink can be used to display video to v4l2 devices (screen overlays
29 * provided by the graphics hardware, tv-out, etc)
32 * <title>Example launch lines</title>
34 * gst-launch videotestsrc ! v4l2sink device=/dev/video1
35 * ]| This pipeline displays a test pattern on /dev/video1
45 #include "gstv4l2colorbalance.h"
47 #include "gstv4l2xoverlay.h"
49 #include "gstv4l2vidorient.h"
51 #include "gstv4l2sink.h"
52 #include "gst/gst-i18n-plugin.h"
56 GST_DEBUG_CATEGORY (v4l2sink_debug);
57 #define GST_CAT_DEFAULT v4l2sink_debug
59 #define PROP_DEF_QUEUE_SIZE 12
60 #define PROP_DEF_MIN_QUEUED_BUFS 1
61 #define DEFAULT_PROP_DEVICE "/dev/video1"
66 V4L2_STD_OBJECT_PROPS,
80 GST_IMPLEMENT_V4L2_PROBE_METHODS (GstV4l2SinkClass, gst_v4l2sink);
81 GST_IMPLEMENT_V4L2_COLOR_BALANCE_METHODS (GstV4l2Sink, gst_v4l2sink);
83 GST_IMPLEMENT_V4L2_XOVERLAY_METHODS (GstV4l2Sink, gst_v4l2sink);
85 GST_IMPLEMENT_V4L2_VIDORIENT_METHODS (GstV4l2Sink, gst_v4l2sink);
88 gst_v4l2sink_iface_supported (GstImplementsInterface * iface, GType iface_type)
90 GstV4l2Object *v4l2object = GST_V4L2SINK (iface)->v4l2object;
93 g_assert (iface_type == GST_TYPE_X_OVERLAY ||
94 iface_type == GST_TYPE_COLOR_BALANCE ||
95 iface_type == GST_TYPE_VIDEO_ORIENTATION);
97 g_assert (iface_type == GST_TYPE_COLOR_BALANCE ||
98 iface_type == GST_TYPE_VIDEO_ORIENTATION);
101 if (v4l2object->video_fd == -1)
105 if (iface_type == GST_TYPE_X_OVERLAY && !GST_V4L2_IS_OVERLAY (v4l2object))
113 gst_v4l2sink_interface_init (GstImplementsInterfaceClass * klass)
116 * default virtual functions
118 klass->supported = gst_v4l2sink_iface_supported;
122 gst_v4l2sink_init_interfaces (GType type)
124 static const GInterfaceInfo v4l2iface_info = {
125 (GInterfaceInitFunc) gst_v4l2sink_interface_init,
130 static const GInterfaceInfo v4l2_xoverlay_info = {
131 (GInterfaceInitFunc) gst_v4l2sink_xoverlay_interface_init,
136 static const GInterfaceInfo v4l2_colorbalance_info = {
137 (GInterfaceInitFunc) gst_v4l2sink_color_balance_interface_init,
141 static const GInterfaceInfo v4l2_videoorientation_info = {
142 (GInterfaceInitFunc) gst_v4l2sink_video_orientation_interface_init,
146 static const GInterfaceInfo v4l2_propertyprobe_info = {
147 (GInterfaceInitFunc) gst_v4l2sink_property_probe_interface_init,
152 g_type_add_interface_static (type,
153 GST_TYPE_IMPLEMENTS_INTERFACE, &v4l2iface_info);
155 g_type_add_interface_static (type, GST_TYPE_X_OVERLAY, &v4l2_xoverlay_info);
157 g_type_add_interface_static (type,
158 GST_TYPE_COLOR_BALANCE, &v4l2_colorbalance_info);
159 g_type_add_interface_static (type,
160 GST_TYPE_VIDEO_ORIENTATION, &v4l2_videoorientation_info);
161 g_type_add_interface_static (type, GST_TYPE_PROPERTY_PROBE,
162 &v4l2_propertyprobe_info);
166 GST_BOILERPLATE_FULL (GstV4l2Sink, gst_v4l2sink, GstVideoSink,
167 GST_TYPE_VIDEO_SINK, gst_v4l2sink_init_interfaces);
170 static void gst_v4l2sink_dispose (GObject * object);
171 static void gst_v4l2sink_finalize (GstV4l2Sink * v4l2sink);
173 /* GObject methods: */
174 static void gst_v4l2sink_set_property (GObject * object, guint prop_id,
175 const GValue * value, GParamSpec * pspec);
176 static void gst_v4l2sink_get_property (GObject * object, guint prop_id,
177 GValue * value, GParamSpec * pspec);
180 /* GstElement methods: */
181 static GstStateChangeReturn gst_v4l2sink_change_state (GstElement * element,
182 GstStateChange transition);
184 /* GstBaseSink methods: */
185 static GstCaps *gst_v4l2sink_get_caps (GstBaseSink * bsink);
186 static gboolean gst_v4l2sink_set_caps (GstBaseSink * bsink, GstCaps * caps);
187 static GstFlowReturn gst_v4l2sink_buffer_alloc (GstBaseSink * bsink,
188 guint64 offset, guint size, GstCaps * caps, GstBuffer ** buf);
189 static GstFlowReturn gst_v4l2sink_show_frame (GstBaseSink * bsink,
194 gst_v4l2sink_base_init (gpointer g_class)
196 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
197 GstV4l2SinkClass *gstv4l2sink_class = GST_V4L2SINK_CLASS (g_class);
199 gstv4l2sink_class->v4l2_class_devices = NULL;
201 GST_DEBUG_CATEGORY_INIT (v4l2sink_debug, "v4l2sink", 0, "V4L2 sink element");
203 gst_element_class_set_details_simple (gstelement_class,
204 "Video (video4linux2) Sink", "Sink/Video",
205 "Displays frames on a video4linux2 device", "Rob Clark <rob@ti.com>,");
207 gst_element_class_add_pad_template
209 gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
210 gst_v4l2_object_get_all_caps ()));
214 gst_v4l2sink_class_init (GstV4l2SinkClass * klass)
216 GObjectClass *gobject_class;
217 GstElementClass *element_class;
218 GstBaseSinkClass *basesink_class;
220 gobject_class = G_OBJECT_CLASS (klass);
221 element_class = GST_ELEMENT_CLASS (klass);
222 basesink_class = GST_BASE_SINK_CLASS (klass);
224 gobject_class->dispose = gst_v4l2sink_dispose;
225 gobject_class->finalize = (GObjectFinalizeFunc) gst_v4l2sink_finalize;
226 gobject_class->set_property = gst_v4l2sink_set_property;
227 gobject_class->get_property = gst_v4l2sink_get_property;
229 element_class->change_state = gst_v4l2sink_change_state;
231 gst_v4l2_object_install_properties_helper (gobject_class,
232 DEFAULT_PROP_DEVICE);
233 g_object_class_install_property (gobject_class, PROP_QUEUE_SIZE,
234 g_param_spec_uint ("queue-size", "Queue size",
235 "Number of buffers to be enqueud in the driver in streaming mode",
236 GST_V4L2_MIN_BUFFERS, GST_V4L2_MAX_BUFFERS, PROP_DEF_QUEUE_SIZE,
237 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
238 g_object_class_install_property (gobject_class, PROP_MIN_QUEUED_BUFS,
239 g_param_spec_uint ("min-queued-bufs", "Minimum queued bufs",
240 "Minimum number of queued bufs; v4l2sink won't dqbuf if the driver "
241 "doesn't have more than this number (which normally you shouldn't change)",
242 0, GST_V4L2_MAX_BUFFERS, PROP_DEF_MIN_QUEUED_BUFS,
243 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
244 g_object_class_install_property (gobject_class, PROP_OVERLAY_TOP,
245 g_param_spec_int ("overlay-top", "Overlay top",
246 "The topmost (y) coordinate of the video overlay; top left corner of screen is 0,0",
247 G_MININT, G_MAXINT, 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
248 g_object_class_install_property (gobject_class, PROP_OVERLAY_LEFT,
249 g_param_spec_int ("overlay-left", "Overlay left",
250 "The leftmost (x) coordinate of the video overlay; top left corner of screen is 0,0",
251 G_MININT, G_MAXINT, 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
252 g_object_class_install_property (gobject_class, PROP_OVERLAY_WIDTH,
253 g_param_spec_uint ("overlay-width", "Overlay width",
254 "The width of the video overlay; default is equal to negotiated image width",
255 0, G_MAXUINT, 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
256 g_object_class_install_property (gobject_class, PROP_OVERLAY_HEIGHT,
257 g_param_spec_uint ("overlay-height", "Overlay height",
258 "The height of the video overlay; default is equal to negotiated image height",
259 0, G_MAXUINT, 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
261 g_object_class_install_property (gobject_class, PROP_CROP_TOP,
262 g_param_spec_int ("crop-top", "Crop top",
263 "The topmost (y) coordinate of the video crop; top left corner of image is 0,0",
264 0x80000000, 0x7fffffff, 0, G_PARAM_READWRITE));
265 g_object_class_install_property (gobject_class, PROP_CROP_LEFT,
266 g_param_spec_int ("crop-left", "Crop left",
267 "The leftmost (x) coordinate of the video crop; top left corner of image is 0,0",
268 0x80000000, 0x7fffffff, 0, G_PARAM_READWRITE));
269 g_object_class_install_property (gobject_class, PROP_CROP_WIDTH,
270 g_param_spec_uint ("crop-width", "Crop width",
271 "The width of the video crop; default is equal to negotiated image width",
272 0, 0xffffffff, 0, G_PARAM_READWRITE));
273 g_object_class_install_property (gobject_class, PROP_CROP_HEIGHT,
274 g_param_spec_uint ("crop-height", "Crop height",
275 "The height of the video crop; default is equal to negotiated image height",
276 0, 0xffffffff, 0, G_PARAM_READWRITE));
278 basesink_class->get_caps = GST_DEBUG_FUNCPTR (gst_v4l2sink_get_caps);
279 basesink_class->set_caps = GST_DEBUG_FUNCPTR (gst_v4l2sink_set_caps);
280 basesink_class->buffer_alloc = GST_DEBUG_FUNCPTR (gst_v4l2sink_buffer_alloc);
281 basesink_class->render = GST_DEBUG_FUNCPTR (gst_v4l2sink_show_frame);
285 gst_v4l2sink_init (GstV4l2Sink * v4l2sink, GstV4l2SinkClass * klass)
287 v4l2sink->v4l2object = gst_v4l2_object_new (GST_ELEMENT (v4l2sink),
288 V4L2_BUF_TYPE_VIDEO_OUTPUT, DEFAULT_PROP_DEVICE,
289 gst_v4l2_get_output, gst_v4l2_set_output, NULL);
291 /* same default value for video output device as is used for
292 * v4l2src/capture is no good.. so lets set a saner default
293 * (which can be overridden by the one creating the v4l2sink
294 * after the constructor returns)
296 g_object_set (v4l2sink, "device", "/dev/video1", NULL);
298 /* number of buffers requested */
299 v4l2sink->num_buffers = PROP_DEF_QUEUE_SIZE;
300 v4l2sink->min_queued_bufs = PROP_DEF_MIN_QUEUED_BUFS;
302 v4l2sink->probed_caps = NULL;
303 v4l2sink->current_caps = NULL;
305 v4l2sink->overlay_fields_set = 0;
306 v4l2sink->crop_fields_set = 0;
312 gst_v4l2sink_dispose (GObject * object)
314 GstV4l2Sink *v4l2sink = GST_V4L2SINK (object);
316 if (v4l2sink->probed_caps) {
317 gst_caps_unref (v4l2sink->probed_caps);
320 if (v4l2sink->current_caps) {
321 gst_caps_unref (v4l2sink->current_caps);
324 G_OBJECT_CLASS (parent_class)->dispose (object);
329 gst_v4l2sink_finalize (GstV4l2Sink * v4l2sink)
331 gst_v4l2_object_destroy (v4l2sink->v4l2object);
333 G_OBJECT_CLASS (parent_class)->finalize ((GObject *) (v4l2sink));
343 STATE_PENDING_STREAMON,
348 * flags to indicate which overlay/crop properties the user has set (and
349 * therefore which ones should override the defaults from the driver)
354 RECT_LEFT_SET = 0x02,
355 RECT_WIDTH_SET = 0x04,
356 RECT_HEIGHT_SET = 0x08
360 gst_v4l2sink_sync_overlay_fields (GstV4l2Sink * v4l2sink)
362 if (!v4l2sink->overlay_fields_set)
365 if (GST_V4L2_IS_OPEN (v4l2sink->v4l2object)) {
367 gint fd = v4l2sink->v4l2object->video_fd;
368 struct v4l2_format format;
370 memset (&format, 0x00, sizeof (struct v4l2_format));
371 format.type = V4L2_BUF_TYPE_VIDEO_OVERLAY;
373 g_return_if_fail (v4l2_ioctl (fd, VIDIOC_G_FMT, &format) >= 0);
375 GST_DEBUG_OBJECT (v4l2sink,
376 "setting overlay: overlay_fields_set=0x%02x, top=%d, left=%d, width=%d, height=%d",
377 v4l2sink->overlay_fields_set,
378 v4l2sink->overlay.top, v4l2sink->overlay.left,
379 v4l2sink->overlay.width, v4l2sink->overlay.height);
381 if (v4l2sink->overlay_fields_set & RECT_TOP_SET)
382 format.fmt.win.w.top = v4l2sink->overlay.top;
383 if (v4l2sink->overlay_fields_set & RECT_LEFT_SET)
384 format.fmt.win.w.left = v4l2sink->overlay.left;
385 if (v4l2sink->overlay_fields_set & RECT_WIDTH_SET)
386 format.fmt.win.w.width = v4l2sink->overlay.width;
387 if (v4l2sink->overlay_fields_set & RECT_HEIGHT_SET)
388 format.fmt.win.w.height = v4l2sink->overlay.height;
390 g_return_if_fail (v4l2_ioctl (fd, VIDIOC_S_FMT, &format) >= 0);
392 v4l2sink->overlay_fields_set = 0;
393 v4l2sink->overlay = format.fmt.win.w;
398 gst_v4l2sink_sync_crop_fields (GstV4l2Sink * v4l2sink)
400 if (!v4l2sink->crop_fields_set)
403 if (GST_V4L2_IS_OPEN (v4l2sink->v4l2object)) {
405 gint fd = v4l2sink->v4l2object->video_fd;
406 struct v4l2_crop crop;
408 memset (&crop, 0x00, sizeof (struct v4l2_crop));
409 crop.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
411 g_return_if_fail (v4l2_ioctl (fd, VIDIOC_G_CROP, &crop) >= 0);
413 GST_DEBUG_OBJECT (v4l2sink,
414 "setting crop: crop_fields_set=0x%02x, top=%d, left=%d, width=%d, height=%d",
415 v4l2sink->crop_fields_set,
416 v4l2sink->crop.top, v4l2sink->crop.left,
417 v4l2sink->crop.width, v4l2sink->crop.height);
419 if (v4l2sink->crop_fields_set & RECT_TOP_SET)
420 crop.c.top = v4l2sink->crop.top;
421 if (v4l2sink->crop_fields_set & RECT_LEFT_SET)
422 crop.c.left = v4l2sink->crop.left;
423 if (v4l2sink->crop_fields_set & RECT_WIDTH_SET)
424 crop.c.width = v4l2sink->crop.width;
425 if (v4l2sink->crop_fields_set & RECT_HEIGHT_SET)
426 crop.c.height = v4l2sink->crop.height;
428 g_return_if_fail (v4l2_ioctl (fd, VIDIOC_S_CROP, &crop) >= 0);
430 v4l2sink->crop_fields_set = 0;
431 v4l2sink->crop = crop.c;
437 gst_v4l2sink_set_property (GObject * object,
438 guint prop_id, const GValue * value, GParamSpec * pspec)
440 GstV4l2Sink *v4l2sink = GST_V4L2SINK (object);
442 if (!gst_v4l2_object_set_property_helper (v4l2sink->v4l2object,
443 prop_id, value, pspec)) {
445 case PROP_QUEUE_SIZE:
446 v4l2sink->num_buffers = g_value_get_uint (value);
448 case PROP_MIN_QUEUED_BUFS:
449 v4l2sink->min_queued_bufs = g_value_get_uint (value);
451 case PROP_OVERLAY_TOP:
452 v4l2sink->overlay.top = g_value_get_int (value);
453 v4l2sink->overlay_fields_set |= RECT_TOP_SET;
454 gst_v4l2sink_sync_overlay_fields (v4l2sink);
456 case PROP_OVERLAY_LEFT:
457 v4l2sink->overlay.left = g_value_get_int (value);
458 v4l2sink->overlay_fields_set |= RECT_LEFT_SET;
459 gst_v4l2sink_sync_overlay_fields (v4l2sink);
461 case PROP_OVERLAY_WIDTH:
462 v4l2sink->overlay.width = g_value_get_uint (value);
463 v4l2sink->overlay_fields_set |= RECT_WIDTH_SET;
464 gst_v4l2sink_sync_overlay_fields (v4l2sink);
466 case PROP_OVERLAY_HEIGHT:
467 v4l2sink->overlay.height = g_value_get_uint (value);
468 v4l2sink->overlay_fields_set |= RECT_HEIGHT_SET;
469 gst_v4l2sink_sync_overlay_fields (v4l2sink);
472 v4l2sink->crop.top = g_value_get_int (value);
473 v4l2sink->crop_fields_set |= RECT_TOP_SET;
474 gst_v4l2sink_sync_crop_fields (v4l2sink);
477 v4l2sink->crop.left = g_value_get_int (value);
478 v4l2sink->crop_fields_set |= RECT_LEFT_SET;
479 gst_v4l2sink_sync_crop_fields (v4l2sink);
481 case PROP_CROP_WIDTH:
482 v4l2sink->crop.width = g_value_get_uint (value);
483 v4l2sink->crop_fields_set |= RECT_WIDTH_SET;
484 gst_v4l2sink_sync_crop_fields (v4l2sink);
486 case PROP_CROP_HEIGHT:
487 v4l2sink->crop.height = g_value_get_uint (value);
488 v4l2sink->crop_fields_set |= RECT_HEIGHT_SET;
489 gst_v4l2sink_sync_crop_fields (v4l2sink);
492 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
500 gst_v4l2sink_get_property (GObject * object,
501 guint prop_id, GValue * value, GParamSpec * pspec)
503 GstV4l2Sink *v4l2sink = GST_V4L2SINK (object);
505 if (!gst_v4l2_object_get_property_helper (v4l2sink->v4l2object,
506 prop_id, value, pspec)) {
508 case PROP_QUEUE_SIZE:
509 g_value_set_uint (value, v4l2sink->num_buffers);
511 case PROP_MIN_QUEUED_BUFS:
512 g_value_set_uint (value, v4l2sink->min_queued_bufs);
514 case PROP_OVERLAY_TOP:
515 g_value_set_int (value, v4l2sink->overlay.top);
517 case PROP_OVERLAY_LEFT:
518 g_value_set_int (value, v4l2sink->overlay.left);
520 case PROP_OVERLAY_WIDTH:
521 g_value_set_uint (value, v4l2sink->overlay.width);
523 case PROP_OVERLAY_HEIGHT:
524 g_value_set_uint (value, v4l2sink->overlay.height);
527 g_value_set_int (value, v4l2sink->crop.top);
530 g_value_set_int (value, v4l2sink->crop.left);
532 case PROP_CROP_WIDTH:
533 g_value_set_uint (value, v4l2sink->crop.width);
535 case PROP_CROP_HEIGHT:
536 g_value_set_uint (value, v4l2sink->crop.height);
539 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
545 static GstStateChangeReturn
546 gst_v4l2sink_change_state (GstElement * element, GstStateChange transition)
548 GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
549 GstV4l2Sink *v4l2sink = GST_V4L2SINK (element);
551 GST_DEBUG_OBJECT (v4l2sink, "%d -> %d",
552 GST_STATE_TRANSITION_CURRENT (transition),
553 GST_STATE_TRANSITION_NEXT (transition));
555 switch (transition) {
556 case GST_STATE_CHANGE_NULL_TO_READY:
557 /* open the device */
558 if (!gst_v4l2_object_start (v4l2sink->v4l2object))
559 return GST_STATE_CHANGE_FAILURE;
565 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
567 switch (transition) {
568 case GST_STATE_CHANGE_PAUSED_TO_READY:
569 if (v4l2sink->state == STATE_STREAMING) {
570 if (!gst_v4l2_object_stop_streaming (v4l2sink->v4l2object)) {
571 return GST_STATE_CHANGE_FAILURE;
573 v4l2sink->state = STATE_PENDING_STREAMON;
576 case GST_STATE_CHANGE_READY_TO_NULL:
577 if (NULL != v4l2sink->pool)
578 gst_v4l2_buffer_pool_destroy (v4l2sink->pool);
579 v4l2sink->pool = NULL;
580 /* close the device */
581 if (!gst_v4l2_object_stop (v4l2sink->v4l2object))
582 return GST_STATE_CHANGE_FAILURE;
583 v4l2sink->state = STATE_OFF;
594 gst_v4l2sink_get_caps (GstBaseSink * bsink)
596 GstV4l2Sink *v4l2sink = GST_V4L2SINK (bsink);
601 if (!GST_V4L2_IS_OPEN (v4l2sink->v4l2object)) {
603 GST_DEBUG_OBJECT (v4l2sink, "device is not open");
605 gst_caps_copy (gst_pad_get_pad_template_caps (GST_BASE_SINK_PAD
609 if (v4l2sink->probed_caps) {
610 LOG_CAPS (v4l2sink, v4l2sink->probed_caps);
611 return gst_caps_ref (v4l2sink->probed_caps);
614 formats = gst_v4l2_object_get_format_list (v4l2sink->v4l2object);
616 ret = gst_caps_new_empty ();
618 for (walk = v4l2sink->v4l2object->formats; walk; walk = walk->next) {
619 struct v4l2_fmtdesc *format;
621 GstStructure *template;
623 format = (struct v4l2_fmtdesc *) walk->data;
625 template = gst_v4l2_object_v4l2fourcc_to_structure (format->pixelformat);
631 gst_v4l2_object_probe_caps_for_format (v4l2sink->v4l2object,
632 format->pixelformat, template);
634 gst_caps_append (ret, tmp);
636 gst_structure_free (template);
638 GST_DEBUG_OBJECT (v4l2sink, "unknown format %u", format->pixelformat);
642 v4l2sink->probed_caps = gst_caps_ref (ret);
644 GST_INFO_OBJECT (v4l2sink, "probed caps: %p", ret);
645 LOG_CAPS (v4l2sink, ret);
651 gst_v4l2sink_set_caps (GstBaseSink * bsink, GstCaps * caps)
653 GstV4l2Sink *v4l2sink = GST_V4L2SINK (bsink);
655 struct v4l2_fmtdesc *format;
659 LOG_CAPS (v4l2sink, caps);
661 if (!GST_V4L2_IS_OPEN (v4l2sink->v4l2object)) {
662 GST_DEBUG_OBJECT (v4l2sink, "device is not open");
666 if (v4l2sink->current_caps) {
667 GST_DEBUG_OBJECT (v4l2sink, "already have caps set.. are they equal?");
668 LOG_CAPS (v4l2sink, v4l2sink->current_caps);
669 if (gst_caps_is_equal (v4l2sink->current_caps, caps)) {
670 GST_DEBUG_OBJECT (v4l2sink, "yes they are!");
673 GST_DEBUG_OBJECT (v4l2sink, "no they aren't!");
676 if (v4l2sink->pool) {
677 /* TODO: if we've already allocated buffers, we probably need to
678 * do something here to free and reallocate....
680 * gst_v4l2_object_stop_streaming()
681 * gst_v4l2_buffer_pool_destroy()
684 GST_DEBUG_OBJECT (v4l2sink, "warning, changing caps not supported yet");
688 /* we want our own v4l2 type of fourcc codes */
689 if (!gst_v4l2_object_get_caps_info (v4l2sink->v4l2object, caps,
690 &format, &w, &h, &fps_n, &fps_d, &size)) {
691 GST_DEBUG_OBJECT (v4l2sink, "can't get capture format from caps %p", caps);
696 GST_DEBUG_OBJECT (v4l2sink, "unrecognized caps!!");
700 if (!gst_v4l2_object_set_format (v4l2sink->v4l2object, format->pixelformat, w,
702 /* error already posted */
706 v4l2sink->current_caps = gst_caps_ref (caps);
711 /* buffer alloc function to implement pad_alloc for upstream element */
713 gst_v4l2sink_buffer_alloc (GstBaseSink * bsink, guint64 offset, guint size,
714 GstCaps * caps, GstBuffer ** buf)
716 GstV4l2Sink *v4l2sink = GST_V4L2SINK (bsink);
717 GstV4l2Buffer *v4l2buf;
719 if (v4l2sink->v4l2object->vcap.capabilities & V4L2_CAP_STREAMING) {
721 /* initialize the buffer pool if not initialized yet (first buffer): */
722 if (G_UNLIKELY (!v4l2sink->pool)) {
724 /* set_caps() might not be called yet.. so just to make sure: */
725 if (!gst_v4l2sink_set_caps (bsink, caps)) {
726 return GST_FLOW_ERROR;
729 GST_V4L2_CHECK_OPEN (v4l2sink->v4l2object);
731 if (!(v4l2sink->pool = gst_v4l2_buffer_pool_new (GST_ELEMENT (v4l2sink),
732 v4l2sink->v4l2object->video_fd,
733 v4l2sink->num_buffers, caps, FALSE,
734 V4L2_BUF_TYPE_VIDEO_OUTPUT))) {
735 return GST_FLOW_ERROR;
738 gst_v4l2sink_sync_overlay_fields (v4l2sink);
739 gst_v4l2sink_sync_crop_fields (v4l2sink);
742 gst_v4l2_xoverlay_prepare_xwindow_id (v4l2sink->v4l2object, TRUE);
745 v4l2sink->state = STATE_PENDING_STREAMON;
747 GST_INFO_OBJECT (v4l2sink, "outputting buffers via mmap()");
749 if (v4l2sink->num_buffers != v4l2sink->pool->buffer_count) {
750 v4l2sink->num_buffers = v4l2sink->pool->buffer_count;
751 g_object_notify (G_OBJECT (v4l2sink), "queue-size");
755 v4l2buf = gst_v4l2_buffer_pool_get (v4l2sink->pool, TRUE);
757 if (G_LIKELY (v4l2buf)) {
758 GST_DEBUG_OBJECT (v4l2sink, "allocated buffer: %p", v4l2buf);
759 *buf = GST_BUFFER (v4l2buf);
762 GST_DEBUG_OBJECT (v4l2sink, "failed to allocate buffer");
763 return GST_FLOW_ERROR;
767 GST_ERROR_OBJECT (v4l2sink, "only supporting streaming mode for now...");
768 return GST_FLOW_ERROR;
772 /* called after A/V sync to render frame */
774 gst_v4l2sink_show_frame (GstBaseSink * bsink, GstBuffer * buf)
776 GstV4l2Sink *v4l2sink = GST_V4L2SINK (bsink);
777 GstBuffer *newbuf = NULL;
779 GST_DEBUG_OBJECT (v4l2sink, "render buffer: %p", buf);
781 if (!GST_IS_V4L2_BUFFER (buf)) {
784 /* special case check for sub-buffers: In certain cases, places like
785 * GstBaseTransform, which might check that the buffer is writable
786 * before copying metadata, timestamp, and such, will find that the
787 * buffer has more than one reference to it. In these cases, they
788 * will create a sub-buffer with an offset=0 and length equal to the
789 * original buffer size.
791 * This could happen in two scenarios: (1) a tee in the pipeline, and
792 * (2) because the refcnt is incremented in gst_mini_object_free()
793 * before the finalize function is called, and decremented after it
794 * returns.. but returning this buffer to the buffer pool in the
795 * finalize function, could wake up a thread blocked in _buffer_alloc()
796 * which could run and get a buffer w/ refcnt==2 before the thread
797 * originally unref'ing the buffer returns from finalize function and
798 * decrements the refcnt back to 1!
801 (GST_BUFFER_DATA (buf) == GST_BUFFER_DATA (buf->parent)) &&
802 (GST_BUFFER_SIZE (buf) == GST_BUFFER_SIZE (buf->parent))) {
803 GST_DEBUG_OBJECT (v4l2sink, "I have a sub-buffer!");
804 return gst_v4l2sink_show_frame (bsink, buf->parent);
807 GST_DEBUG_OBJECT (v4l2sink, "slow-path.. I got a %s so I need to memcpy",
808 g_type_name (G_OBJECT_TYPE (buf)));
810 ret = gst_v4l2sink_buffer_alloc (bsink,
811 GST_BUFFER_OFFSET (buf), GST_BUFFER_SIZE (buf), GST_BUFFER_CAPS (buf),
814 if (GST_FLOW_OK != ret) {
815 GST_DEBUG_OBJECT (v4l2sink,
816 "dropping frame! Consider increasing 'queue-size' property!");
820 memcpy (GST_BUFFER_DATA (newbuf),
821 GST_BUFFER_DATA (buf),
822 MIN (GST_BUFFER_SIZE (newbuf), GST_BUFFER_SIZE (buf)));
824 GST_DEBUG_OBJECT (v4l2sink, "render copied buffer: %p", newbuf);
829 if (!gst_v4l2_buffer_pool_qbuf (v4l2sink->pool, GST_V4L2_BUFFER (buf))) {
830 return GST_FLOW_ERROR;
832 if (v4l2sink->state == STATE_PENDING_STREAMON) {
833 if (!gst_v4l2_object_start_streaming (v4l2sink->v4l2object)) {
834 return GST_FLOW_ERROR;
836 v4l2sink->state = STATE_STREAMING;
840 gst_buffer_ref (buf);
843 /* if the driver has more than one buffer, ie. more than just the one we
844 * just queued, then dequeue one immediately to make it available via
847 if (gst_v4l2_buffer_pool_available_buffers (v4l2sink->pool) >
848 v4l2sink->min_queued_bufs) {
849 GstV4l2Buffer *v4l2buf = gst_v4l2_buffer_pool_dqbuf (v4l2sink->pool);
851 /* note: if we get a buf, we don't want to use it directly (because
852 * someone else could still hold a ref).. but instead we release our
853 * reference to it, and if no one else holds a ref it will be returned
854 * to the pool of available buffers.. and if not, we keep looping.
857 gst_buffer_unref (GST_BUFFER (v4l2buf));