3 * Copyright (C) 2001-2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
4 * 2006 Edgard Lima <edgard.lima@indt.org.br>
5 * 2009 Texas Instruments, Inc - http://www.ti.com/
7 * gstv4l2bufferpool.c V4L2 buffer pool class
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., 51 Franklin St, Fifth Floor,
22 * Boston, MA 02110-1301, USA.
30 # define _GNU_SOURCE /* O_CLOEXEC */
38 #include "gst/video/video.h"
39 #include "gst/video/gstvideometa.h"
40 #include "gst/video/gstvideopool.h"
41 #include "gst/allocators/gstdmabuf.h"
43 #include <gstv4l2bufferpool.h>
45 #include "v4l2_calls.h"
46 #include "gst/gst-i18n-plugin.h"
47 #include <gst/glib-compat-private.h>
49 GST_DEBUG_CATEGORY_EXTERN (v4l2_debug);
50 GST_DEBUG_CATEGORY_EXTERN (GST_CAT_PERFORMANCE);
51 #define GST_CAT_DEFAULT v4l2_debug
53 #define GST_V4L2_IMPORT_QUARK gst_v4l2_buffer_pool_import_quark ()
59 #define gst_v4l2_buffer_pool_parent_class parent_class
60 G_DEFINE_TYPE (GstV4l2BufferPool, gst_v4l2_buffer_pool, GST_TYPE_BUFFER_POOL);
62 enum _GstV4l2BufferPoolAcquireFlags
64 GST_V4L2_POOL_ACQUIRE_FLAG_RESURECT = GST_BUFFER_POOL_ACQUIRE_FLAG_LAST,
65 GST_V4L2_BUFFER_POOL_ACQUIRE_FAG_LAST
68 static void gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool,
72 gst_v4l2_is_buffer_valid (GstBuffer * buffer, GstV4l2MemoryGroup ** group)
74 GstMemory *mem = gst_buffer_peek_memory (buffer, 0);
75 gboolean valid = FALSE;
77 if (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY))
80 if (gst_is_dmabuf_memory (mem))
81 mem = gst_mini_object_get_qdata (GST_MINI_OBJECT (mem),
82 GST_V4L2_MEMORY_QUARK);
84 if (mem && gst_is_v4l2_memory (mem)) {
85 GstV4l2Memory *vmem = (GstV4l2Memory *) mem;
96 gst_v4l2_buffer_pool_copy_buffer (GstV4l2BufferPool * pool, GstBuffer * dest,
99 const GstVideoFormatInfo *finfo = pool->caps_info.finfo;
101 GST_LOG_OBJECT (pool, "copying buffer");
103 if (finfo && (finfo->format != GST_VIDEO_FORMAT_UNKNOWN &&
104 finfo->format != GST_VIDEO_FORMAT_ENCODED)) {
105 GstVideoFrame src_frame, dest_frame;
107 GST_DEBUG_OBJECT (pool, "copy video frame");
109 /* we have raw video, use videoframe copy to get strides right */
110 if (!gst_video_frame_map (&src_frame, &pool->caps_info, src, GST_MAP_READ))
113 if (!gst_video_frame_map (&dest_frame, &pool->caps_info, dest,
115 gst_video_frame_unmap (&src_frame);
119 gst_video_frame_copy (&dest_frame, &src_frame);
121 gst_video_frame_unmap (&src_frame);
122 gst_video_frame_unmap (&dest_frame);
126 GST_DEBUG_OBJECT (pool, "copy raw bytes");
128 if (!gst_buffer_map (src, &map, GST_MAP_READ))
131 gst_buffer_fill (dest, 0, map.data, gst_buffer_get_size (src));
133 gst_buffer_unmap (src, &map);
134 gst_buffer_resize (dest, 0, gst_buffer_get_size (src));
137 GST_CAT_LOG_OBJECT (GST_CAT_PERFORMANCE, pool, "slow copy into buffer %p",
144 GST_ERROR_OBJECT (pool, "could not map buffer");
145 return GST_FLOW_ERROR;
158 gst_v4l2_buffer_pool_import_quark (void)
160 static GQuark quark = 0;
163 quark = g_quark_from_string ("GstV4l2BufferPoolUsePtrData");
169 _unmap_userptr_frame (struct UserPtrData *data)
172 gst_video_frame_unmap (&data->frame);
174 gst_buffer_unmap (data->buffer, &data->map);
177 gst_buffer_unref (data->buffer);
179 g_slice_free (struct UserPtrData, data);
183 gst_v4l2_buffer_pool_import_userptr (GstV4l2BufferPool * pool,
184 GstBuffer * dest, GstBuffer * src)
186 GstFlowReturn ret = GST_FLOW_OK;
187 GstV4l2MemoryGroup *group = NULL;
189 const GstVideoFormatInfo *finfo = pool->caps_info.finfo;
190 struct UserPtrData *data = NULL;
192 GST_LOG_OBJECT (pool, "importing userptr");
195 if (!gst_v4l2_is_buffer_valid (dest, &group))
198 if (V4L2_TYPE_IS_OUTPUT (pool->obj->type))
199 flags = GST_MAP_READ;
201 flags = GST_MAP_WRITE;
203 data = g_slice_new0 (struct UserPtrData);
205 if (finfo && (finfo->format != GST_VIDEO_FORMAT_UNKNOWN &&
206 finfo->format != GST_VIDEO_FORMAT_ENCODED)) {
207 data->is_frame = TRUE;
209 if (!gst_video_frame_map (&data->frame, &pool->caps_info, src, flags))
212 if (!gst_v4l2_allocator_import_userptr (pool->vallocator, group,
213 data->frame.info.size, finfo->n_planes, data->frame.data,
214 data->frame.info.offset))
217 gsize offset[1] = { 0 };
220 data->is_frame = FALSE;
222 if (!gst_buffer_map (src, &data->map, flags))
225 ptr[0] = data->map.data;
227 if (!gst_v4l2_allocator_import_userptr (pool->vallocator, group,
228 data->map.size, 1, ptr, offset))
232 data->buffer = gst_buffer_ref (src);
234 gst_mini_object_set_qdata (GST_MINI_OBJECT (dest), GST_V4L2_IMPORT_QUARK,
235 data, (GDestroyNotify) _unmap_userptr_frame);
241 GST_ERROR_OBJECT (pool, "destination buffer invalid or not from our pool");
242 return GST_FLOW_ERROR;
246 GST_ERROR_OBJECT (pool, "could not map buffer");
247 g_slice_free (struct UserPtrData, data);
248 return GST_FLOW_ERROR;
252 GST_ERROR_OBJECT (pool, "failed to import data");
253 _unmap_userptr_frame (data);
254 return GST_FLOW_ERROR;
259 gst_v4l2_buffer_pool_import_dmabuf (GstV4l2BufferPool * pool,
260 GstBuffer * dest, GstBuffer * src)
262 GstV4l2MemoryGroup *group = NULL;
263 GstMemory *dma_mem[GST_VIDEO_MAX_PLANES] = { 0 };
264 guint n_mem = gst_buffer_n_memory (src);
267 GST_LOG_OBJECT (pool, "importing dmabuf");
269 if (!gst_v4l2_is_buffer_valid (dest, &group))
272 if (n_mem > GST_VIDEO_MAX_PLANES)
275 for (i = 0; i < n_mem; i++)
276 dma_mem[i] = gst_buffer_peek_memory (src, i);
278 if (!gst_v4l2_allocator_import_dmabuf (pool->vallocator, group, n_mem,
282 gst_mini_object_set_qdata (GST_MINI_OBJECT (dest), GST_V4L2_IMPORT_QUARK,
283 gst_buffer_ref (src), (GDestroyNotify) gst_buffer_unref);
289 GST_ERROR_OBJECT (pool, "destination buffer invalid or not from our pool");
290 return GST_FLOW_ERROR;
294 GST_ERROR_OBJECT (pool, "could not map buffer");
295 return GST_FLOW_ERROR;
299 GST_ERROR_OBJECT (pool, "failed to import dmabuf");
300 return GST_FLOW_ERROR;
305 gst_v4l2_buffer_pool_prepare_buffer (GstV4l2BufferPool * pool,
306 GstBuffer * dest, GstBuffer * src)
308 GstFlowReturn ret = GST_FLOW_OK;
309 gboolean own_src = FALSE;
312 if (pool->other_pool == NULL) {
313 GST_ERROR_OBJECT (pool, "can't prepare buffer, source buffer missing");
314 return GST_FLOW_ERROR;
317 ret = gst_buffer_pool_acquire_buffer (pool->other_pool, &src, NULL);
318 if (ret != GST_FLOW_OK) {
319 GST_ERROR_OBJECT (pool, "failed to acquire buffer from downstream pool");
326 switch (pool->obj->mode) {
327 case GST_V4L2_IO_MMAP:
328 case GST_V4L2_IO_DMABUF:
329 ret = gst_v4l2_buffer_pool_copy_buffer (pool, dest, src);
331 case GST_V4L2_IO_USERPTR:
332 ret = gst_v4l2_buffer_pool_import_userptr (pool, dest, src);
334 case GST_V4L2_IO_DMABUF_IMPORT:
335 ret = gst_v4l2_buffer_pool_import_dmabuf (pool, dest, src);
342 gst_buffer_unref (src);
349 gst_v4l2_buffer_pool_alloc_buffer (GstBufferPool * bpool, GstBuffer ** buffer,
350 GstBufferPoolAcquireParams * params)
352 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
353 GstV4l2MemoryGroup *group = NULL;
354 GstBuffer *newbuf = NULL;
364 gst_buffer_new_allocate (pool->allocator, pool->size, &pool->params);
366 case GST_V4L2_IO_MMAP:
367 group = gst_v4l2_allocator_alloc_mmap (pool->vallocator);
369 case GST_V4L2_IO_DMABUF:
370 group = gst_v4l2_allocator_alloc_dmabuf (pool->vallocator,
373 case GST_V4L2_IO_USERPTR:
374 group = gst_v4l2_allocator_alloc_userptr (pool->vallocator);
376 case GST_V4L2_IO_DMABUF_IMPORT:
377 group = gst_v4l2_allocator_alloc_dmabufin (pool->vallocator);
381 g_assert_not_reached ();
387 newbuf = gst_buffer_new ();
389 for (i = 0; i < group->n_mem; i++)
390 gst_buffer_append_memory (newbuf, group->mem[i]);
391 } else if (newbuf == NULL) {
392 goto allocation_failed;
395 /* add metadata to raw video buffers */
396 if (pool->add_videometa)
397 gst_buffer_add_video_meta_full (newbuf, GST_VIDEO_FRAME_FLAG_NONE,
398 GST_VIDEO_INFO_FORMAT (info), GST_VIDEO_INFO_WIDTH (info),
399 GST_VIDEO_INFO_HEIGHT (info), GST_VIDEO_INFO_N_PLANES (info),
400 info->offset, info->stride);
409 GST_ERROR_OBJECT (pool, "failed to allocate buffer");
410 return GST_FLOW_ERROR;
415 gst_v4l2_buffer_pool_set_config (GstBufferPool * bpool, GstStructure * config)
417 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
418 GstV4l2Object *obj = pool->obj;
420 guint size, min_buffers, max_buffers;
421 GstAllocator *allocator;
422 GstAllocationParams params;
423 gboolean can_allocate = FALSE;
424 gboolean updated = FALSE;
427 pool->add_videometa =
428 gst_buffer_pool_config_has_option (config,
429 GST_BUFFER_POOL_OPTION_VIDEO_META);
431 /* parse the config and keep around */
432 if (!gst_buffer_pool_config_get_params (config, &caps, &size, &min_buffers,
436 if (!gst_buffer_pool_config_get_allocator (config, &allocator, ¶ms))
439 GST_DEBUG_OBJECT (pool, "config %" GST_PTR_FORMAT, config);
442 gst_object_unref (pool->allocator);
443 pool->allocator = NULL;
446 case GST_V4L2_IO_DMABUF:
447 pool->allocator = gst_dmabuf_allocator_new ();
448 can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP);
450 case GST_V4L2_IO_MMAP:
451 can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP);
453 case GST_V4L2_IO_USERPTR:
455 GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, USERPTR);
457 case GST_V4L2_IO_DMABUF_IMPORT:
458 can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, DMABUF);
461 pool->allocator = g_object_ref (allocator);
462 pool->params = params;
463 /* No need to change the configuration */
467 g_assert_not_reached ();
471 if (min_buffers < GST_V4L2_MIN_BUFFERS) {
473 min_buffers = GST_V4L2_MIN_BUFFERS;
474 GST_INFO_OBJECT (pool, "increasing minimum buffers to %u", min_buffers);
477 if (max_buffers > VIDEO_MAX_FRAME || max_buffers == 0) {
479 max_buffers = VIDEO_MAX_FRAME;
480 GST_INFO_OBJECT (pool, "reducing maximum buffers to %u", max_buffers);
483 if (min_buffers > max_buffers) {
485 min_buffers = max_buffers;
486 GST_INFO_OBJECT (pool, "reducing minimum buffers to %u", min_buffers);
487 } else if (min_buffers != max_buffers) {
490 max_buffers = min_buffers;
491 GST_INFO_OBJECT (pool, "can't allocate, setting maximum to minimum");
495 if (!pool->add_videometa && obj->need_video_meta) {
496 GST_INFO_OBJECT (pool, "adding needed video meta");
498 gst_buffer_pool_config_add_option (config,
499 GST_BUFFER_POOL_OPTION_VIDEO_META);
503 gst_buffer_pool_config_set_params (config, caps, size, min_buffers,
506 /* keep a GstVideoInfo with defaults for the when we need to copy */
507 gst_video_info_from_caps (&pool->caps_info, caps);
510 ret = GST_BUFFER_POOL_CLASS (parent_class)->set_config (bpool, config);
512 /* If anything was changed documentation recommand to return FALSE */
513 return !updated && ret;
518 GST_ERROR_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config);
524 gst_v4l2_buffer_pool_streamon (GstV4l2BufferPool * pool)
526 GstV4l2Object *obj = pool->obj;
529 case GST_V4L2_IO_MMAP:
530 case GST_V4L2_IO_USERPTR:
531 case GST_V4L2_IO_DMABUF:
532 case GST_V4L2_IO_DMABUF_IMPORT:
533 if (!pool->streaming) {
534 if (v4l2_ioctl (pool->video_fd, VIDIOC_STREAMON, &obj->type) < 0)
535 goto streamon_failed;
537 pool->streaming = TRUE;
539 GST_DEBUG_OBJECT (pool, "Started streaming");
550 GST_ERROR_OBJECT (pool, "error with STREAMON %d (%s)", errno,
557 gst_v4l2_buffer_pool_streamoff (GstV4l2BufferPool * pool)
559 GstV4l2Object *obj = pool->obj;
562 case GST_V4L2_IO_MMAP:
563 case GST_V4L2_IO_USERPTR:
564 case GST_V4L2_IO_DMABUF:
565 case GST_V4L2_IO_DMABUF_IMPORT:
566 if (pool->streaming) {
567 if (v4l2_ioctl (pool->video_fd, VIDIOC_STREAMOFF, &obj->type) < 0)
568 goto streamoff_failed;
570 pool->streaming = FALSE;
572 GST_DEBUG_OBJECT (pool, "Stopped streaming");
583 GST_ERROR_OBJECT (pool, "error with STREAMOFF %d (%s)", errno,
590 gst_v4l2_buffer_pool_group_released (GstV4l2BufferPool * pool)
592 GstBufferPoolAcquireParams params = { 0 };
593 GstBuffer *buffer = NULL;
596 GST_DEBUG_OBJECT (pool, "A buffer was lost, reallocating it");
599 (GstBufferPoolAcquireFlags) GST_V4L2_POOL_ACQUIRE_FLAG_RESURECT;
601 gst_buffer_pool_acquire_buffer (GST_BUFFER_POOL (pool), &buffer, ¶ms);
603 if (ret == GST_FLOW_OK)
604 gst_buffer_unref (buffer);
608 gst_v4l2_buffer_pool_start (GstBufferPool * bpool)
610 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
611 GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class);
612 GstV4l2Object *obj = pool->obj;
613 GstStructure *config;
615 guint size, min_buffers, max_buffers;
616 guint max_latency, min_latency, copy_threshold = 0;
617 gboolean can_allocate = FALSE;
619 GST_DEBUG_OBJECT (pool, "activating pool");
621 config = gst_buffer_pool_get_config (bpool);
622 if (!gst_buffer_pool_config_get_params (config, &caps, &size, &min_buffers,
626 min_latency = MAX (GST_V4L2_MIN_BUFFERS, obj->min_buffers);
632 case GST_V4L2_IO_DMABUF:
633 case GST_V4L2_IO_MMAP:
637 can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP);
639 /* first, lets request buffers, and see how many we can get: */
640 GST_DEBUG_OBJECT (pool, "requesting %d MMAP buffers", min_buffers);
642 count = gst_v4l2_allocator_start (pool->vallocator, min_buffers,
645 if (count < GST_V4L2_MIN_BUFFERS) {
650 /* V4L2 buffer pool are often very limited in the amount of buffers it
651 * can offer. The copy_threshold will workaround this limitation by
652 * falling back to copy if the pipeline needed more buffers. This also
653 * prevent having to do REQBUFS(N)/REQBUFS(0) everytime configure is
655 if (count != min_buffers) {
656 GST_WARNING_OBJECT (pool, "using %u buffers instead of %u",
659 copy_threshold = min_latency;
661 /* The initial minimum could be provide either by GstBufferPool or
668 case GST_V4L2_IO_USERPTR:
673 GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, USERPTR);
675 GST_DEBUG_OBJECT (pool, "requesting %d USERPTR buffers", min_buffers);
677 count = gst_v4l2_allocator_start (pool->vallocator, min_buffers,
678 V4L2_MEMORY_USERPTR);
680 /* There is no rational to not get what we asked */
681 if (count < min_buffers) {
689 case GST_V4L2_IO_DMABUF_IMPORT:
693 can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, DMABUF);
695 GST_DEBUG_OBJECT (pool, "requesting %d DMABUF buffers", min_buffers);
697 count = gst_v4l2_allocator_start (pool->vallocator, min_buffers,
700 /* There is no rational to not get what we asked */
701 if (count < min_buffers) {
712 g_assert_not_reached ();
717 max_latency = max_buffers;
719 max_latency = min_buffers;
722 pool->copy_threshold = copy_threshold;
723 pool->max_latency = max_latency;
724 pool->min_latency = min_latency;
725 pool->num_queued = 0;
727 if (max_buffers < min_buffers)
728 max_buffers = min_buffers;
730 gst_buffer_pool_config_set_params (config, caps, size, min_buffers,
732 pclass->set_config (bpool, config);
733 gst_structure_free (config);
735 if (pool->other_pool)
736 if (!gst_buffer_pool_set_active (pool->other_pool, TRUE))
737 goto other_pool_failed;
739 /* now, allocate the buffers: */
740 if (!pclass->start (bpool))
743 if (!V4L2_TYPE_IS_OUTPUT (obj->type))
744 pool->group_released_handler =
745 g_signal_connect_swapped (pool->vallocator, "group-released",
746 G_CALLBACK (gst_v4l2_buffer_pool_group_released), pool);
753 GST_ERROR_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config);
754 gst_structure_free (config);
759 GST_ERROR_OBJECT (pool,
760 "we received %d buffer from device '%s', we want at least %d",
761 min_buffers, obj->videodev, GST_V4L2_MIN_BUFFERS);
762 gst_structure_free (config);
767 GST_ERROR_OBJECT (pool, "failed to start streaming");
772 GST_ERROR_OBJECT (pool, "failed to active the other pool %"
773 GST_PTR_FORMAT, pool->other_pool);
779 gst_v4l2_buffer_pool_stop (GstBufferPool * bpool)
781 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
782 GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class);
786 GST_DEBUG_OBJECT (pool, "stopping pool");
788 if (pool->group_released_handler > 0) {
789 g_signal_handler_disconnect (pool->vallocator,
790 pool->group_released_handler);
791 pool->group_released_handler = 0;
794 if (pool->other_pool) {
795 gst_object_unref (pool->other_pool);
796 pool->other_pool = NULL;
799 if (!gst_v4l2_buffer_pool_streamoff (pool))
800 goto streamoff_failed;
802 gst_v4l2_allocator_flush (pool->vallocator);
804 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
805 if (pool->buffers[i]) {
806 GstBuffer *buffer = pool->buffers[i];
808 pool->buffers[i] = NULL;
810 if (V4L2_TYPE_IS_OUTPUT (pool->obj->type))
811 gst_buffer_unref (buffer);
813 pclass->release_buffer (bpool, buffer);
815 g_atomic_int_add (&pool->num_queued, -1);
819 ret = GST_BUFFER_POOL_CLASS (parent_class)->stop (bpool);
824 vret = gst_v4l2_allocator_stop (pool->vallocator);
826 if (vret == GST_V4L2_BUSY)
827 GST_WARNING_OBJECT (pool, "some buffers are still outstanding");
829 ret = (vret == GST_V4L2_OK);
836 GST_ERROR_OBJECT (pool, "device refused to stop streaming");
841 gst_v4l2_buffer_pool_flush_start (GstBufferPool * bpool)
843 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
845 GST_DEBUG_OBJECT (pool, "start flushing");
847 gst_poll_set_flushing (pool->poll, TRUE);
849 GST_OBJECT_LOCK (pool);
851 g_cond_broadcast (&pool->empty_cond);
852 GST_OBJECT_UNLOCK (pool);
854 if (pool->other_pool)
855 gst_buffer_pool_set_flushing (pool->other_pool, TRUE);
859 gst_v4l2_buffer_pool_flush_stop (GstBufferPool * bpool)
861 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
862 GstV4l2Object *obj = pool->obj;
865 GST_DEBUG_OBJECT (pool, "stop flushing");
867 /* If we haven't started streaming yet, simply call streamon */
868 if (!pool->streaming)
871 if (pool->other_pool)
872 gst_buffer_pool_set_flushing (pool->other_pool, FALSE);
874 if (!gst_v4l2_buffer_pool_streamoff (pool))
877 gst_v4l2_allocator_flush (pool->vallocator);
879 /* Reset our state */
883 case GST_V4L2_IO_MMAP:
884 case GST_V4L2_IO_USERPTR:
885 case GST_V4L2_IO_DMABUF:
886 case GST_V4L2_IO_DMABUF_IMPORT:
890 num_allocated = gst_v4l2_allocator_num_allocated (pool->vallocator);
892 for (i = 0; i < num_allocated; i++) {
893 /* Re-enqueue buffers */
894 if (pool->buffers[i]) {
895 GstBufferPool *bpool = (GstBufferPool *) pool;
896 GstBuffer *buffer = pool->buffers[i];
898 pool->buffers[i] = NULL;
900 /* Remove qdata, this will unmap any map data in
901 * userptr/dmabuf-import */
902 gst_mini_object_set_qdata (GST_MINI_OBJECT (buffer),
903 GST_V4L2_IMPORT_QUARK, NULL, NULL);
905 if (V4L2_TYPE_IS_OUTPUT (obj->type))
906 gst_buffer_unref (buffer);
908 gst_v4l2_buffer_pool_release_buffer (bpool, buffer);
910 g_atomic_int_add (&pool->num_queued, -1);
917 g_assert_not_reached ();
922 /* Start streaming on capture device only */
923 if (!V4L2_TYPE_IS_OUTPUT (obj->type))
924 gst_v4l2_buffer_pool_streamon (pool);
926 gst_poll_set_flushing (pool->poll, FALSE);
933 GST_ERROR_OBJECT (pool, "device refused to flush");
938 gst_v4l2_buffer_pool_poll (GstV4l2BufferPool * pool)
942 GST_OBJECT_LOCK (pool);
944 g_cond_wait (&pool->empty_cond, GST_OBJECT_GET_LOCK (pool));
945 GST_OBJECT_UNLOCK (pool);
947 if (!pool->can_poll_device)
950 GST_LOG_OBJECT (pool, "polling device");
953 ret = gst_poll_wait (pool->poll, GST_CLOCK_TIME_NONE);
954 if (G_UNLIKELY (ret < 0)) {
962 GST_WARNING_OBJECT (pool,
963 "v4l2 device doesn't support polling. Disabling"
964 " using libv4l2 in this case may cause deadlocks");
965 pool->can_poll_device = FALSE;
972 if (gst_poll_fd_has_error (pool->poll, &pool->pollfd))
981 GST_DEBUG_OBJECT (pool, "stop called");
982 return GST_FLOW_FLUSHING;
986 GST_ELEMENT_ERROR (pool->obj->element, RESOURCE, READ, (NULL),
987 ("poll error %d: %s (%d)", ret, g_strerror (errno), errno));
988 return GST_FLOW_ERROR;
993 gst_v4l2_buffer_pool_qbuf (GstV4l2BufferPool * pool, GstBuffer * buf)
995 GstV4l2MemoryGroup *group = NULL;
998 if (!gst_v4l2_is_buffer_valid (buf, &group)) {
999 GST_LOG_OBJECT (pool, "unref copied/invalid buffer %p", buf);
1000 gst_buffer_unref (buf);
1004 index = group->buffer.index;
1006 if (pool->buffers[index] != NULL)
1007 goto already_queued;
1009 GST_LOG_OBJECT (pool, "queuing buffer %i", index);
1011 g_atomic_int_inc (&pool->num_queued);
1012 pool->buffers[index] = buf;
1014 if (!gst_v4l2_allocator_qbuf (pool->vallocator, group))
1017 GST_OBJECT_LOCK (pool);
1018 pool->empty = FALSE;
1019 g_cond_signal (&pool->empty_cond);
1020 GST_OBJECT_UNLOCK (pool);
1026 GST_ERROR_OBJECT (pool, "the buffer %i was already queued", index);
1027 return GST_FLOW_ERROR;
1031 GST_ERROR_OBJECT (pool, "could not queue a buffer %i", index);
1032 /* Mark broken buffer to the allocator */
1033 GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_TAG_MEMORY);
1034 g_atomic_int_add (&pool->num_queued, -1);
1035 pool->buffers[index] = NULL;
1036 return GST_FLOW_ERROR;
1040 static GstFlowReturn
1041 gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer)
1045 GstV4l2Object *obj = pool->obj;
1046 GstClockTime timestamp;
1047 GstV4l2MemoryGroup *group;
1050 if ((res = gst_v4l2_buffer_pool_poll (pool)) != GST_FLOW_OK)
1053 GST_LOG_OBJECT (pool, "dequeueing a buffer");
1055 group = gst_v4l2_allocator_dqbuf (pool->vallocator);
1059 /* get our GstBuffer with that index from the pool, if the buffer was
1060 * outstanding we have a serious problem.
1062 outbuf = pool->buffers[group->buffer.index];
1066 /* mark the buffer outstanding */
1067 pool->buffers[group->buffer.index] = NULL;
1068 if (g_atomic_int_dec_and_test (&pool->num_queued)) {
1069 GST_OBJECT_LOCK (pool);
1071 GST_OBJECT_UNLOCK (pool);
1074 timestamp = GST_TIMEVAL_TO_TIME (group->buffer.timestamp);
1076 #ifndef GST_DISABLE_GST_DEBUG
1077 for (i = 0; i < group->n_mem; i++) {
1078 GST_LOG_OBJECT (pool,
1079 "dequeued buffer %p seq:%d (ix=%d), mem %p used %d, plane=%d, flags %08x, ts %"
1080 GST_TIME_FORMAT ", pool-queued=%d, buffer=%p", outbuf,
1081 group->buffer.sequence, group->buffer.index, group->mem[i],
1082 group->planes[i].bytesused, i, group->buffer.flags,
1083 GST_TIME_ARGS (timestamp), pool->num_queued, outbuf);
1087 /* set top/bottom field first if v4l2_buffer has the information */
1088 if (group->buffer.field == V4L2_FIELD_INTERLACED_TB) {
1089 GST_BUFFER_FLAG_SET (outbuf, GST_VIDEO_BUFFER_FLAG_INTERLACED);
1090 GST_BUFFER_FLAG_SET (outbuf, GST_VIDEO_BUFFER_FLAG_TFF);
1091 } else if (group->buffer.field == V4L2_FIELD_INTERLACED_BT) {
1092 GST_BUFFER_FLAG_SET (outbuf, GST_VIDEO_BUFFER_FLAG_INTERLACED);
1093 GST_BUFFER_FLAG_UNSET (outbuf, GST_VIDEO_BUFFER_FLAG_TFF);
1095 GST_BUFFER_FLAG_UNSET (outbuf, GST_VIDEO_BUFFER_FLAG_INTERLACED);
1096 GST_BUFFER_FLAG_UNSET (outbuf, GST_VIDEO_BUFFER_FLAG_TFF);
1099 if (GST_VIDEO_INFO_FORMAT (&obj->info) == GST_VIDEO_FORMAT_ENCODED) {
1100 if (group->buffer.flags & V4L2_BUF_FLAG_KEYFRAME)
1101 GST_BUFFER_FLAG_UNSET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
1103 GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
1106 GST_BUFFER_TIMESTAMP (outbuf) = timestamp;
1115 GST_DEBUG_OBJECT (pool, "poll error %s", gst_flow_get_name (res));
1120 return GST_FLOW_ERROR;
1124 GST_ERROR_OBJECT (pool, "No free buffer found in the pool at index %d.",
1125 group->buffer.index);
1126 return GST_FLOW_ERROR;
1130 static GstFlowReturn
1131 gst_v4l2_buffer_pool_acquire_buffer (GstBufferPool * bpool, GstBuffer ** buffer,
1132 GstBufferPoolAcquireParams * params)
1135 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
1136 GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class);
1137 GstV4l2Object *obj = pool->obj;
1139 GST_DEBUG_OBJECT (pool, "acquire");
1141 /* If this is being called to resurect a lost buffer */
1142 if (params && params->flags & GST_V4L2_POOL_ACQUIRE_FLAG_RESURECT) {
1143 ret = pclass->acquire_buffer (bpool, buffer, params);
1147 switch (obj->type) {
1148 case V4L2_BUF_TYPE_VIDEO_CAPTURE:
1149 case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
1150 /* capture, This function should return a buffer with new captured data */
1151 switch (obj->mode) {
1152 case GST_V4L2_IO_RW:
1154 /* take empty buffer from the pool */
1155 ret = pclass->acquire_buffer (bpool, buffer, params);
1158 case GST_V4L2_IO_DMABUF:
1159 case GST_V4L2_IO_MMAP:
1161 /* just dequeue a buffer, we basically use the queue of v4l2 as the
1162 * storage for our buffers. This function does poll first so we can
1163 * interrupt it fine. */
1164 ret = gst_v4l2_buffer_pool_dqbuf (pool, buffer);
1165 if (G_UNLIKELY (ret != GST_FLOW_OK))
1169 case GST_V4L2_IO_USERPTR:
1170 case GST_V4L2_IO_DMABUF_IMPORT:
1172 /* dequeue filled buffer */
1173 ret = gst_v4l2_buffer_pool_dqbuf (pool, buffer);
1177 ret = GST_FLOW_ERROR;
1178 g_assert_not_reached ();
1184 case V4L2_BUF_TYPE_VIDEO_OUTPUT:
1185 case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
1186 /* playback, This function should return an empty buffer */
1187 switch (obj->mode) {
1188 case GST_V4L2_IO_RW:
1189 /* get an empty buffer */
1190 ret = pclass->acquire_buffer (bpool, buffer, params);
1193 case GST_V4L2_IO_MMAP:
1194 case GST_V4L2_IO_DMABUF:
1195 case GST_V4L2_IO_USERPTR:
1196 case GST_V4L2_IO_DMABUF_IMPORT:
1197 /* get a free unqueued buffer */
1198 ret = pclass->acquire_buffer (bpool, buffer, params);
1202 ret = GST_FLOW_ERROR;
1203 g_assert_not_reached ();
1209 ret = GST_FLOW_ERROR;
1210 g_assert_not_reached ();
1218 gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool, GstBuffer * buffer)
1220 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
1221 GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class);
1222 GstV4l2Object *obj = pool->obj;
1224 GST_DEBUG_OBJECT (pool, "release buffer %p", buffer);
1226 switch (obj->type) {
1227 case V4L2_BUF_TYPE_VIDEO_CAPTURE:
1228 case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
1229 /* capture, put the buffer back in the queue so that we can refill it
1231 switch (obj->mode) {
1232 case GST_V4L2_IO_RW:
1233 /* release back in the pool */
1234 pclass->release_buffer (bpool, buffer);
1237 case GST_V4L2_IO_DMABUF:
1238 case GST_V4L2_IO_MMAP:
1239 case GST_V4L2_IO_USERPTR:
1240 case GST_V4L2_IO_DMABUF_IMPORT:
1242 if (gst_v4l2_is_buffer_valid (buffer, NULL)) {
1243 /* queue back in the device */
1244 if (pool->other_pool)
1245 gst_v4l2_buffer_pool_prepare_buffer (pool, buffer, NULL);
1246 if (gst_v4l2_buffer_pool_qbuf (pool, buffer) != GST_FLOW_OK)
1247 pclass->release_buffer (bpool, buffer);
1249 /* Simply release invalide/modified buffer, the allocator will
1250 * give it back later */
1251 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
1252 pclass->release_buffer (bpool, buffer);
1257 g_assert_not_reached ();
1262 case V4L2_BUF_TYPE_VIDEO_OUTPUT:
1263 case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
1264 switch (obj->mode) {
1265 case GST_V4L2_IO_RW:
1266 /* release back in the pool */
1267 pclass->release_buffer (bpool, buffer);
1270 case GST_V4L2_IO_MMAP:
1271 case GST_V4L2_IO_DMABUF:
1272 case GST_V4L2_IO_USERPTR:
1273 case GST_V4L2_IO_DMABUF_IMPORT:
1275 GstV4l2MemoryGroup *group;
1278 if (!gst_v4l2_is_buffer_valid (buffer, &group)) {
1279 /* Simply release invalide/modified buffer, the allocator will
1280 * give it back later */
1281 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
1282 pclass->release_buffer (bpool, buffer);
1286 index = group->buffer.index;
1288 if (pool->buffers[index] == NULL) {
1289 GST_LOG_OBJECT (pool, "buffer %u not queued, putting on free list",
1292 /* Remove qdata, this will unmap any map data in userptr */
1293 gst_mini_object_set_qdata (GST_MINI_OBJECT (buffer),
1294 GST_V4L2_IMPORT_QUARK, NULL, NULL);
1296 /* reset to default size */
1297 gst_v4l2_allocator_reset_group (pool->vallocator, group);
1299 /* playback, put the buffer back in the queue to refill later. */
1300 pclass->release_buffer (bpool, buffer);
1302 /* We keep a ref on queued buffer, so this should never happen */
1303 g_assert_not_reached ();
1309 g_assert_not_reached ();
1315 g_assert_not_reached ();
1321 gst_v4l2_buffer_pool_finalize (GObject * object)
1323 GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (object);
1326 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1327 if (pool->buffers[i])
1328 gst_buffer_replace (&(pool->buffers[i]), NULL);
1331 if (pool->video_fd >= 0)
1332 v4l2_close (pool->video_fd);
1334 gst_poll_free (pool->poll);
1336 if (pool->vallocator)
1337 gst_object_unref (pool->vallocator);
1339 if (pool->allocator)
1340 gst_object_unref (pool->allocator);
1342 if (pool->other_pool)
1343 gst_object_unref (pool->other_pool);
1345 /* FIXME Is this required to keep around ? */
1346 gst_object_unref (pool->obj->element);
1348 g_cond_clear (&pool->empty_cond);
1350 /* FIXME have we done enough here ? */
1352 G_OBJECT_CLASS (parent_class)->finalize (object);
1356 gst_v4l2_buffer_pool_init (GstV4l2BufferPool * pool)
1358 pool->poll = gst_poll_new (TRUE);
1359 pool->can_poll_device = TRUE;
1360 g_cond_init (&pool->empty_cond);
1365 gst_v4l2_buffer_pool_class_init (GstV4l2BufferPoolClass * klass)
1367 GObjectClass *object_class = G_OBJECT_CLASS (klass);
1368 GstBufferPoolClass *bufferpool_class = GST_BUFFER_POOL_CLASS (klass);
1370 object_class->finalize = gst_v4l2_buffer_pool_finalize;
1372 bufferpool_class->start = gst_v4l2_buffer_pool_start;
1373 bufferpool_class->stop = gst_v4l2_buffer_pool_stop;
1374 bufferpool_class->set_config = gst_v4l2_buffer_pool_set_config;
1375 bufferpool_class->alloc_buffer = gst_v4l2_buffer_pool_alloc_buffer;
1376 bufferpool_class->acquire_buffer = gst_v4l2_buffer_pool_acquire_buffer;
1377 bufferpool_class->release_buffer = gst_v4l2_buffer_pool_release_buffer;
1378 bufferpool_class->flush_start = gst_v4l2_buffer_pool_flush_start;
1379 bufferpool_class->flush_stop = gst_v4l2_buffer_pool_flush_stop;
1383 * gst_v4l2_buffer_pool_new:
1384 * @obj: the v4l2 object owning the pool
1386 * Construct a new buffer pool.
1388 * Returns: the new pool, use gst_object_unref() to free resources
1391 gst_v4l2_buffer_pool_new (GstV4l2Object * obj, GstCaps * caps)
1393 GstV4l2BufferPool *pool;
1394 GstStructure *config;
1395 gchar *name, *parent_name;
1398 fd = v4l2_dup (obj->video_fd);
1402 /* setting a significant unique name */
1403 parent_name = gst_object_get_name (GST_OBJECT (obj->element));
1404 name = g_strconcat (parent_name, ":", "pool:",
1405 V4L2_TYPE_IS_OUTPUT (obj->type) ? "sink" : "src", NULL);
1406 g_free (parent_name);
1408 pool = (GstV4l2BufferPool *) g_object_new (GST_TYPE_V4L2_BUFFER_POOL,
1409 "name", name, NULL);
1412 gst_poll_fd_init (&pool->pollfd);
1413 pool->pollfd.fd = fd;
1414 gst_poll_add_fd (pool->poll, &pool->pollfd);
1415 if (V4L2_TYPE_IS_OUTPUT (obj->type))
1416 gst_poll_fd_ctl_write (pool->poll, &pool->pollfd, TRUE);
1418 gst_poll_fd_ctl_read (pool->poll, &pool->pollfd, TRUE);
1420 pool->video_fd = fd;
1422 pool->can_poll_device = TRUE;
1425 gst_v4l2_allocator_new (GST_OBJECT (pool), obj->video_fd, &obj->format);
1426 if (pool->vallocator == NULL)
1427 goto allocator_failed;
1429 gst_object_ref (obj->element);
1431 config = gst_buffer_pool_get_config (GST_BUFFER_POOL_CAST (pool));
1432 gst_buffer_pool_config_set_params (config, caps, obj->info.size, 0, 0);
1433 /* This will simply set a default config, but will not configure the pool
1434 * because min and max are not valid */
1435 gst_buffer_pool_set_config (GST_BUFFER_POOL_CAST (pool), config);
1437 return GST_BUFFER_POOL (pool);
1442 GST_ERROR ("failed to dup fd %d (%s)", errno, g_strerror (errno));
1447 GST_ERROR_OBJECT (pool, "Failed to create V4L2 allocator");
1452 static GstFlowReturn
1453 gst_v4l2_do_read (GstV4l2BufferPool * pool, GstBuffer * buf)
1456 GstV4l2Object *obj = pool->obj;
1461 toread = obj->info.size;
1463 GST_LOG_OBJECT (pool, "reading %d bytes into buffer %p", toread, buf);
1465 gst_buffer_map (buf, &map, GST_MAP_WRITE);
1468 if ((res = gst_v4l2_buffer_pool_poll (pool)) != GST_FLOW_OK)
1471 amount = v4l2_read (obj->video_fd, map.data, toread);
1473 if (amount == toread) {
1475 } else if (amount == -1) {
1476 if (errno == EAGAIN || errno == EINTR) {
1481 /* short reads can happen if a signal interrupts the read */
1486 GST_LOG_OBJECT (pool, "read %d bytes", amount);
1487 gst_buffer_unmap (buf, &map);
1488 gst_buffer_resize (buf, 0, amount);
1495 GST_DEBUG ("poll error %s", gst_flow_get_name (res));
1500 GST_ELEMENT_ERROR (obj->element, RESOURCE, READ,
1501 (_("Error reading %d bytes from device '%s'."),
1502 toread, obj->videodev), GST_ERROR_SYSTEM);
1503 res = GST_FLOW_ERROR;
1508 gst_buffer_unmap (buf, &map);
1509 gst_buffer_resize (buf, 0, 0);
1515 * gst_v4l2_buffer_pool_process:
1516 * @bpool: a #GstBufferPool
1517 * @buf: a #GstBuffer, maybe be replaced
1519 * Process @buf in @bpool. For capture devices, this functions fills @buf with
1520 * data from the device. For output devices, this functions send the contents of
1521 * @buf to the device for playback.
1523 * Returns: %GST_FLOW_OK on success.
1526 gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
1528 GstFlowReturn ret = GST_FLOW_OK;
1529 GstBufferPool *bpool = GST_BUFFER_POOL_CAST (pool);
1530 GstV4l2Object *obj = pool->obj;
1532 GST_DEBUG_OBJECT (pool, "process buffer %p", buf);
1534 g_return_val_if_fail (gst_buffer_pool_is_active (bpool), GST_FLOW_ERROR);
1536 if (GST_BUFFER_POOL_IS_FLUSHING (pool))
1537 return GST_FLOW_FLUSHING;
1539 switch (obj->type) {
1540 case V4L2_BUF_TYPE_VIDEO_CAPTURE:
1541 case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
1543 switch (obj->mode) {
1544 case GST_V4L2_IO_RW:
1545 /* capture into the buffer */
1546 ret = gst_v4l2_do_read (pool, *buf);
1549 case GST_V4L2_IO_MMAP:
1550 case GST_V4L2_IO_DMABUF:
1554 if ((*buf)->pool == bpool) {
1555 if (gst_buffer_get_size (*buf) == 0)
1558 /* start copying buffers when we are running low on buffers */
1559 if (g_atomic_int_get (&pool->num_queued) < pool->copy_threshold) {
1562 if (GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP)) {
1564 if (gst_buffer_pool_acquire_buffer (bpool, ©,
1565 NULL) == GST_FLOW_OK) {
1566 gst_v4l2_buffer_pool_release_buffer (bpool, copy);
1571 /* copy the buffer */
1572 copy = gst_buffer_copy_region (*buf,
1573 GST_BUFFER_COPY_ALL | GST_BUFFER_COPY_DEEP, 0, -1);
1574 GST_LOG_OBJECT (pool, "copy buffer %p->%p", *buf, copy);
1576 /* and requeue so that we can continue capturing */
1577 gst_buffer_unref (*buf);
1581 /* nothing, data was inside the buffer when we did _acquire() */
1585 /* buffer not from our pool, grab a frame and copy it into the target */
1586 if ((ret = gst_v4l2_buffer_pool_dqbuf (pool, &tmp)) != GST_FLOW_OK)
1589 /* An empty buffer on capture indicates the end of stream */
1590 if (gst_buffer_get_size (tmp) == 0) {
1591 gst_v4l2_buffer_pool_release_buffer (bpool, tmp);
1595 ret = gst_v4l2_buffer_pool_copy_buffer (pool, *buf, tmp);
1597 /* an queue the buffer again after the copy */
1598 gst_v4l2_buffer_pool_release_buffer (bpool, tmp);
1600 if (ret != GST_FLOW_OK)
1605 case GST_V4L2_IO_USERPTR:
1607 struct UserPtrData *data;
1609 /* Replace our buffer with downstream allocated buffer */
1610 data = gst_mini_object_steal_qdata (GST_MINI_OBJECT (*buf),
1611 GST_V4L2_IMPORT_QUARK);
1612 gst_buffer_replace (buf, data->buffer);
1613 _unmap_userptr_frame (data);
1617 case GST_V4L2_IO_DMABUF_IMPORT:
1621 /* Replace our buffer with downstream allocated buffer */
1622 tmp = gst_mini_object_steal_qdata (GST_MINI_OBJECT (*buf),
1623 GST_V4L2_IMPORT_QUARK);
1624 gst_buffer_replace (buf, tmp);
1625 gst_buffer_unref (tmp);
1630 g_assert_not_reached ();
1635 case V4L2_BUF_TYPE_VIDEO_OUTPUT:
1636 case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
1638 switch (obj->mode) {
1639 case GST_V4L2_IO_RW:
1640 /* FIXME, do write() */
1641 GST_WARNING_OBJECT (pool, "implement write()");
1644 case GST_V4L2_IO_USERPTR:
1645 case GST_V4L2_IO_DMABUF_IMPORT:
1646 case GST_V4L2_IO_DMABUF:
1647 case GST_V4L2_IO_MMAP:
1649 GstBuffer *to_queue = NULL;
1650 GstV4l2MemoryGroup *group;
1653 if ((*buf)->pool != bpool)
1656 if (!gst_v4l2_is_buffer_valid (*buf, &group))
1659 index = group->buffer.index;
1661 GST_LOG_OBJECT (pool, "processing buffer %i from our pool", index);
1663 index = group->buffer.index;
1664 if (pool->buffers[index] != NULL) {
1665 GST_LOG_OBJECT (pool, "buffer %i already queued, copying", index);
1669 /* we can queue directly */
1670 to_queue = gst_buffer_ref (*buf);
1673 if (to_queue == NULL) {
1674 GstBufferPoolAcquireParams params = { 0 };
1676 GST_LOG_OBJECT (pool, "alloc buffer from our pool");
1678 /* this can return EOS if all buffers are outstanding which would
1679 * be strange because we would expect the upstream element to have
1680 * allocated them and returned to us.. */
1681 params.flags = GST_BUFFER_POOL_ACQUIRE_FLAG_DONTWAIT;
1682 ret = gst_buffer_pool_acquire_buffer (bpool, &to_queue, ¶ms);
1683 if (ret != GST_FLOW_OK)
1684 goto acquire_failed;
1686 ret = gst_v4l2_buffer_pool_prepare_buffer (pool, to_queue, *buf);
1687 if (ret != GST_FLOW_OK) {
1688 gst_buffer_unref (to_queue);
1689 goto prepare_failed;
1693 if ((ret = gst_v4l2_buffer_pool_qbuf (pool, to_queue)) != GST_FLOW_OK)
1696 /* if we are not streaming yet (this is the first buffer, start
1698 if (!gst_v4l2_buffer_pool_streamon (pool)) {
1699 gst_buffer_unref (to_queue);
1703 if (g_atomic_int_get (&pool->num_queued) >= pool->min_latency) {
1705 /* all buffers are queued, try to dequeue one and release it back
1706 * into the pool so that _acquire can get to it again. */
1707 ret = gst_v4l2_buffer_pool_dqbuf (pool, &out);
1708 if (ret == GST_FLOW_OK)
1709 /* release the rendered buffer back into the pool. This wakes up any
1710 * thread waiting for a buffer in _acquire(). */
1711 gst_buffer_unref (out);
1716 g_assert_not_reached ();
1721 g_assert_not_reached ();
1730 GST_ERROR_OBJECT (pool, "failed to copy buffer");
1735 GST_DEBUG_OBJECT (pool, "end of stream reached");
1736 return GST_FLOW_EOS;
1740 if (ret == GST_FLOW_FLUSHING)
1741 GST_DEBUG_OBJECT (pool, "flushing");
1743 GST_WARNING_OBJECT (pool, "failed to acquire a buffer: %s",
1744 gst_flow_get_name (ret));
1749 GST_ERROR_OBJECT (pool, "failed to prepare data");
1754 GST_ERROR_OBJECT (pool, "failed to queue buffer");
1759 GST_ERROR_OBJECT (pool, "failed to start streaming");
1760 return GST_FLOW_ERROR;
1765 gst_v4l2_buffer_pool_set_other_pool (GstV4l2BufferPool * pool,
1766 GstBufferPool * other_pool)
1768 g_return_if_fail (!gst_buffer_pool_is_active (GST_BUFFER_POOL (pool)));
1770 if (pool->other_pool)
1771 gst_object_unref (pool->other_pool);
1772 pool->other_pool = gst_object_ref (other_pool);