/* GStreamer * * Copyright (C) 2001-2002 Ronald Bultje * 2006 Edgard Lima * 2009 Texas Instruments, Inc - http://www.ti.com/ * * gstv4l2bufferpool.c V4L2 buffer pool class * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ #ifdef HAVE_CONFIG_H # include #endif #ifndef _GNU_SOURCE # define _GNU_SOURCE /* O_CLOEXEC */ #endif #include #include #include #include #include "gst/video/video.h" #include "gst/video/gstvideometa.h" #include "gst/video/gstvideopool.h" #include "gst/allocators/gstdmabuf.h" #include #include "v4l2_calls.h" #include "gst/gst-i18n-plugin.h" #include GST_DEBUG_CATEGORY_EXTERN (v4l2_debug); GST_DEBUG_CATEGORY_EXTERN (GST_CAT_PERFORMANCE); #define GST_CAT_DEFAULT v4l2_debug #define GST_V4L2_IMPORT_QUARK gst_v4l2_buffer_pool_import_quark () /* * GstV4l2BufferPool: */ #define gst_v4l2_buffer_pool_parent_class parent_class G_DEFINE_TYPE (GstV4l2BufferPool, gst_v4l2_buffer_pool, GST_TYPE_BUFFER_POOL); enum _GstV4l2BufferPoolAcquireFlags { GST_V4L2_POOL_ACQUIRE_FLAG_RESURECT = GST_BUFFER_POOL_ACQUIRE_FLAG_LAST, GST_V4L2_BUFFER_POOL_ACQUIRE_FAG_LAST }; static void gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool, GstBuffer * buffer); static gboolean gst_v4l2_is_buffer_valid (GstBuffer * buffer, GstV4l2MemoryGroup ** group) { GstMemory *mem = gst_buffer_peek_memory (buffer, 0); gboolean valid = FALSE; if (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY)) goto done; if (gst_is_dmabuf_memory (mem)) mem = gst_mini_object_get_qdata (GST_MINI_OBJECT (mem), GST_V4L2_MEMORY_QUARK); if (mem && gst_is_v4l2_memory (mem)) { GstV4l2Memory *vmem = (GstV4l2Memory *) mem; valid = TRUE; if (group) *group = vmem->group; } done: return valid; } static GstFlowReturn gst_v4l2_buffer_pool_copy_buffer (GstV4l2BufferPool * pool, GstBuffer * dest, GstBuffer * src) { const GstVideoFormatInfo *finfo = pool->caps_info.finfo; GST_LOG_OBJECT (pool, "copying buffer"); if (finfo && (finfo->format != GST_VIDEO_FORMAT_UNKNOWN && finfo->format != GST_VIDEO_FORMAT_ENCODED)) { GstVideoFrame src_frame, dest_frame; GST_DEBUG_OBJECT (pool, "copy video frame"); /* we have raw video, use videoframe copy to get strides right */ if (!gst_video_frame_map (&src_frame, &pool->caps_info, src, GST_MAP_READ)) goto invalid_buffer; if (!gst_video_frame_map (&dest_frame, &pool->caps_info, dest, GST_MAP_WRITE)) { gst_video_frame_unmap (&src_frame); goto invalid_buffer; } gst_video_frame_copy (&dest_frame, &src_frame); gst_video_frame_unmap (&src_frame); gst_video_frame_unmap (&dest_frame); } else { GstMapInfo map; GST_DEBUG_OBJECT (pool, "copy raw bytes"); if (!gst_buffer_map (src, &map, GST_MAP_READ)) goto invalid_buffer; gst_buffer_fill (dest, 0, map.data, gst_buffer_get_size (src)); gst_buffer_unmap (src, &map); gst_buffer_resize (dest, 0, gst_buffer_get_size (src)); } GST_CAT_LOG_OBJECT (GST_CAT_PERFORMANCE, pool, "slow copy into buffer %p", dest); return GST_FLOW_OK; invalid_buffer: { GST_ERROR_OBJECT (pool, "could not map buffer"); return GST_FLOW_ERROR; } } struct UserPtrData { GstBuffer *buffer; gboolean is_frame; GstVideoFrame frame; GstMapInfo map; }; static GQuark gst_v4l2_buffer_pool_import_quark (void) { static GQuark quark = 0; if (quark == 0) quark = g_quark_from_string ("GstV4l2BufferPoolUsePtrData"); return quark; } static void _unmap_userptr_frame (struct UserPtrData *data) { if (data->is_frame) gst_video_frame_unmap (&data->frame); else gst_buffer_unmap (data->buffer, &data->map); if (data->buffer) gst_buffer_unref (data->buffer); g_slice_free (struct UserPtrData, data); } static GstFlowReturn gst_v4l2_buffer_pool_import_userptr (GstV4l2BufferPool * pool, GstBuffer * dest, GstBuffer * src) { GstFlowReturn ret = GST_FLOW_OK; GstV4l2MemoryGroup *group = NULL; GstMapFlags flags; const GstVideoFormatInfo *finfo = pool->caps_info.finfo; struct UserPtrData *data = NULL; GST_LOG_OBJECT (pool, "importing userptr"); /* get the group */ if (!gst_v4l2_is_buffer_valid (dest, &group)) goto not_our_buffer; if (V4L2_TYPE_IS_OUTPUT (pool->obj->type)) flags = GST_MAP_READ; else flags = GST_MAP_WRITE; data = g_slice_new0 (struct UserPtrData); if (finfo && (finfo->format != GST_VIDEO_FORMAT_UNKNOWN && finfo->format != GST_VIDEO_FORMAT_ENCODED)) { data->is_frame = TRUE; if (!gst_video_frame_map (&data->frame, &pool->caps_info, src, flags)) goto invalid_buffer; if (!gst_v4l2_allocator_import_userptr (pool->vallocator, group, data->frame.info.size, finfo->n_planes, data->frame.data, data->frame.info.offset)) goto import_failed; } else { gsize offset[1] = { 0 }; gpointer ptr[1]; data->is_frame = FALSE; if (!gst_buffer_map (src, &data->map, flags)) goto invalid_buffer; ptr[0] = data->map.data; if (!gst_v4l2_allocator_import_userptr (pool->vallocator, group, data->map.size, 1, ptr, offset)) goto import_failed; } data->buffer = gst_buffer_ref (src); gst_mini_object_set_qdata (GST_MINI_OBJECT (dest), GST_V4L2_IMPORT_QUARK, data, (GDestroyNotify) _unmap_userptr_frame); return ret; not_our_buffer: { GST_ERROR_OBJECT (pool, "destination buffer invalid or not from our pool"); return GST_FLOW_ERROR; } invalid_buffer: { GST_ERROR_OBJECT (pool, "could not map buffer"); g_slice_free (struct UserPtrData, data); return GST_FLOW_ERROR; } import_failed: { GST_ERROR_OBJECT (pool, "failed to import data"); _unmap_userptr_frame (data); return GST_FLOW_ERROR; } } static GstFlowReturn gst_v4l2_buffer_pool_import_dmabuf (GstV4l2BufferPool * pool, GstBuffer * dest, GstBuffer * src) { GstV4l2MemoryGroup *group = NULL; GstMemory *dma_mem[GST_VIDEO_MAX_PLANES] = { 0 }; guint n_mem = gst_buffer_n_memory (src); gint i; GST_LOG_OBJECT (pool, "importing dmabuf"); if (!gst_v4l2_is_buffer_valid (dest, &group)) goto not_our_buffer; if (n_mem > GST_VIDEO_MAX_PLANES) goto too_many_mems; for (i = 0; i < n_mem; i++) dma_mem[i] = gst_buffer_peek_memory (src, i); if (!gst_v4l2_allocator_import_dmabuf (pool->vallocator, group, n_mem, dma_mem)) goto import_failed; gst_mini_object_set_qdata (GST_MINI_OBJECT (dest), GST_V4L2_IMPORT_QUARK, gst_buffer_ref (src), (GDestroyNotify) gst_buffer_unref); return GST_FLOW_OK; not_our_buffer: { GST_ERROR_OBJECT (pool, "destination buffer invalid or not from our pool"); return GST_FLOW_ERROR; } too_many_mems: { GST_ERROR_OBJECT (pool, "could not map buffer"); return GST_FLOW_ERROR; } import_failed: { GST_ERROR_OBJECT (pool, "failed to import dmabuf"); return GST_FLOW_ERROR; } } static GstFlowReturn gst_v4l2_buffer_pool_prepare_buffer (GstV4l2BufferPool * pool, GstBuffer * dest, GstBuffer * src) { GstFlowReturn ret = GST_FLOW_OK; gboolean own_src = FALSE; if (src == NULL) { if (pool->other_pool == NULL) { GST_ERROR_OBJECT (pool, "can't prepare buffer, source buffer missing"); return GST_FLOW_ERROR; } ret = gst_buffer_pool_acquire_buffer (pool->other_pool, &src, NULL); if (ret != GST_FLOW_OK) { GST_ERROR_OBJECT (pool, "failed to acquire buffer from downstream pool"); goto done; } own_src = TRUE; } switch (pool->obj->mode) { case GST_V4L2_IO_MMAP: case GST_V4L2_IO_DMABUF: ret = gst_v4l2_buffer_pool_copy_buffer (pool, dest, src); break; case GST_V4L2_IO_USERPTR: ret = gst_v4l2_buffer_pool_import_userptr (pool, dest, src); break; case GST_V4L2_IO_DMABUF_IMPORT: ret = gst_v4l2_buffer_pool_import_dmabuf (pool, dest, src); break; default: break; } if (own_src) gst_buffer_unref (src); done: return ret; } static GstFlowReturn gst_v4l2_buffer_pool_alloc_buffer (GstBufferPool * bpool, GstBuffer ** buffer, GstBufferPoolAcquireParams * params) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GstV4l2MemoryGroup *group = NULL; GstBuffer *newbuf = NULL; GstV4l2Object *obj; GstVideoInfo *info; obj = pool->obj; info = &obj->info; switch (obj->mode) { case GST_V4L2_IO_RW: newbuf = gst_buffer_new_allocate (pool->allocator, pool->size, &pool->params); break; case GST_V4L2_IO_MMAP: group = gst_v4l2_allocator_alloc_mmap (pool->vallocator); break; case GST_V4L2_IO_DMABUF: group = gst_v4l2_allocator_alloc_dmabuf (pool->vallocator, pool->allocator); break; case GST_V4L2_IO_USERPTR: group = gst_v4l2_allocator_alloc_userptr (pool->vallocator); break; case GST_V4L2_IO_DMABUF_IMPORT: group = gst_v4l2_allocator_alloc_dmabufin (pool->vallocator); break; default: newbuf = NULL; g_assert_not_reached (); break; } if (group != NULL) { gint i; newbuf = gst_buffer_new (); for (i = 0; i < group->n_mem; i++) gst_buffer_append_memory (newbuf, group->mem[i]); } else if (newbuf == NULL) { goto allocation_failed; } /* add metadata to raw video buffers */ if (pool->add_videometa) gst_buffer_add_video_meta_full (newbuf, GST_VIDEO_FRAME_FLAG_NONE, GST_VIDEO_INFO_FORMAT (info), GST_VIDEO_INFO_WIDTH (info), GST_VIDEO_INFO_HEIGHT (info), GST_VIDEO_INFO_N_PLANES (info), info->offset, info->stride); *buffer = newbuf; return GST_FLOW_OK; /* ERRORS */ allocation_failed: { GST_ERROR_OBJECT (pool, "failed to allocate buffer"); return GST_FLOW_ERROR; } } static gboolean gst_v4l2_buffer_pool_set_config (GstBufferPool * bpool, GstStructure * config) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GstV4l2Object *obj = pool->obj; GstCaps *caps; guint size, min_buffers, max_buffers; GstAllocator *allocator; GstAllocationParams params; gboolean can_allocate = FALSE; gboolean updated = FALSE; gboolean ret; pool->add_videometa = gst_buffer_pool_config_has_option (config, GST_BUFFER_POOL_OPTION_VIDEO_META); /* parse the config and keep around */ if (!gst_buffer_pool_config_get_params (config, &caps, &size, &min_buffers, &max_buffers)) goto wrong_config; if (!gst_buffer_pool_config_get_allocator (config, &allocator, ¶ms)) goto wrong_config; GST_DEBUG_OBJECT (pool, "config %" GST_PTR_FORMAT, config); if (pool->allocator) gst_object_unref (pool->allocator); pool->allocator = NULL; switch (obj->mode) { case GST_V4L2_IO_DMABUF: pool->allocator = gst_dmabuf_allocator_new (); can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP); break; case GST_V4L2_IO_MMAP: can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP); break; case GST_V4L2_IO_USERPTR: can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, USERPTR); break; case GST_V4L2_IO_DMABUF_IMPORT: can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, DMABUF); break; case GST_V4L2_IO_RW: pool->allocator = g_object_ref (allocator); pool->params = params; /* No need to change the configuration */ goto done; break; default: g_assert_not_reached (); break; } if (min_buffers < GST_V4L2_MIN_BUFFERS) { updated = TRUE; min_buffers = GST_V4L2_MIN_BUFFERS; GST_INFO_OBJECT (pool, "increasing minimum buffers to %u", min_buffers); } if (max_buffers > VIDEO_MAX_FRAME || max_buffers == 0) { updated = TRUE; max_buffers = VIDEO_MAX_FRAME; GST_INFO_OBJECT (pool, "reducing maximum buffers to %u", max_buffers); } if (min_buffers > max_buffers) { updated = TRUE; min_buffers = max_buffers; GST_INFO_OBJECT (pool, "reducing minimum buffers to %u", min_buffers); } else if (min_buffers != max_buffers) { if (!can_allocate) { updated = TRUE; max_buffers = min_buffers; GST_INFO_OBJECT (pool, "can't allocate, setting maximum to minimum"); } } if (!pool->add_videometa && obj->need_video_meta) { GST_INFO_OBJECT (pool, "adding needed video meta"); updated = TRUE; gst_buffer_pool_config_add_option (config, GST_BUFFER_POOL_OPTION_VIDEO_META); } if (updated) gst_buffer_pool_config_set_params (config, caps, size, min_buffers, max_buffers); /* keep a GstVideoInfo with defaults for the when we need to copy */ gst_video_info_from_caps (&pool->caps_info, caps); done: ret = GST_BUFFER_POOL_CLASS (parent_class)->set_config (bpool, config); /* If anything was changed documentation recommand to return FALSE */ return !updated && ret; /* ERRORS */ wrong_config: { GST_ERROR_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config); return FALSE; } } static gboolean gst_v4l2_buffer_pool_streamon (GstV4l2BufferPool * pool) { GstV4l2Object *obj = pool->obj; switch (obj->mode) { case GST_V4L2_IO_MMAP: case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_DMABUF_IMPORT: if (!pool->streaming) { if (v4l2_ioctl (pool->video_fd, VIDIOC_STREAMON, &obj->type) < 0) goto streamon_failed; pool->streaming = TRUE; GST_DEBUG_OBJECT (pool, "Started streaming"); } break; default: break; } return TRUE; streamon_failed: { GST_ERROR_OBJECT (pool, "error with STREAMON %d (%s)", errno, g_strerror (errno)); return FALSE; } } static gboolean gst_v4l2_buffer_pool_streamoff (GstV4l2BufferPool * pool) { GstV4l2Object *obj = pool->obj; switch (obj->mode) { case GST_V4L2_IO_MMAP: case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_DMABUF_IMPORT: if (pool->streaming) { if (v4l2_ioctl (pool->video_fd, VIDIOC_STREAMOFF, &obj->type) < 0) goto streamoff_failed; pool->streaming = FALSE; GST_DEBUG_OBJECT (pool, "Stopped streaming"); } break; default: break; } return TRUE; streamoff_failed: { GST_ERROR_OBJECT (pool, "error with STREAMOFF %d (%s)", errno, g_strerror (errno)); return FALSE; } } static void gst_v4l2_buffer_pool_group_released (GstV4l2BufferPool * pool) { GstBufferPoolAcquireParams params = { 0 }; GstBuffer *buffer = NULL; GstFlowReturn ret; GST_DEBUG_OBJECT (pool, "A buffer was lost, reallocating it"); params.flags = (GstBufferPoolAcquireFlags) GST_V4L2_POOL_ACQUIRE_FLAG_RESURECT; ret = gst_buffer_pool_acquire_buffer (GST_BUFFER_POOL (pool), &buffer, ¶ms); if (ret == GST_FLOW_OK) gst_buffer_unref (buffer); } static gboolean gst_v4l2_buffer_pool_start (GstBufferPool * bpool) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class); GstV4l2Object *obj = pool->obj; GstStructure *config; GstCaps *caps; guint size, min_buffers, max_buffers; guint max_latency, min_latency, copy_threshold = 0; gboolean can_allocate = FALSE; GST_DEBUG_OBJECT (pool, "activating pool"); config = gst_buffer_pool_get_config (bpool); if (!gst_buffer_pool_config_get_params (config, &caps, &size, &min_buffers, &max_buffers)) goto wrong_config; /* TODO Also consider min_buffers_for_output when implemented */ min_latency = MAX (GST_V4L2_MIN_BUFFERS, obj->min_buffers_for_capture); switch (obj->mode) { case GST_V4L2_IO_RW: can_allocate = TRUE; break; case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_MMAP: { guint count; can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP); /* first, lets request buffers, and see how many we can get: */ GST_DEBUG_OBJECT (pool, "requesting %d MMAP buffers", min_buffers); count = gst_v4l2_allocator_start (pool->vallocator, min_buffers, V4L2_MEMORY_MMAP); if (count < GST_V4L2_MIN_BUFFERS) { min_buffers = count; goto no_buffers; } /* V4L2 buffer pool are often very limited in the amount of buffers it * can offer. The copy_threshold will workaround this limitation by * falling back to copy if the pipeline needed more buffers. This also * prevent having to do REQBUFS(N)/REQBUFS(0) everytime configure is * called. */ if (count != min_buffers) { GST_WARNING_OBJECT (pool, "using %u buffers instead of %u", count, min_buffers); min_buffers = count; copy_threshold = min_latency; /* The initial minimum could be provide either by GstBufferPool or * driver needs. */ min_buffers = count; } break; } case GST_V4L2_IO_USERPTR: { guint count; can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, USERPTR); GST_DEBUG_OBJECT (pool, "requesting %d USERPTR buffers", min_buffers); count = gst_v4l2_allocator_start (pool->vallocator, min_buffers, V4L2_MEMORY_USERPTR); /* There is no rational to not get what we asked */ if (count < min_buffers) { min_buffers = count; goto no_buffers; } min_buffers = count; break; } case GST_V4L2_IO_DMABUF_IMPORT: { guint count; can_allocate = GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, DMABUF); GST_DEBUG_OBJECT (pool, "requesting %d DMABUF buffers", min_buffers); count = gst_v4l2_allocator_start (pool->vallocator, min_buffers, V4L2_MEMORY_DMABUF); /* There is no rational to not get what we asked */ if (count < min_buffers) { min_buffers = count; goto no_buffers; } min_buffers = count; break; } default: min_buffers = 0; copy_threshold = 0; g_assert_not_reached (); break; } if (can_allocate) max_latency = max_buffers; else max_latency = min_buffers; /* FIXME Encoder don't negotiate amount of buffers. If we can't grow the * pool, or the minimum is at V4L2 maximum, enabled copy on threshold * https://bugzilla.gnome.org/show_bug.cgi?id=732288 */ if (!can_allocate || min_buffers == VIDEO_MAX_FRAME) copy_threshold = min_latency; pool->size = size; pool->copy_threshold = copy_threshold; pool->max_latency = max_latency; pool->min_latency = min_latency; pool->num_queued = 0; if (max_buffers < min_buffers) max_buffers = min_buffers; gst_buffer_pool_config_set_params (config, caps, size, min_buffers, max_buffers); pclass->set_config (bpool, config); gst_structure_free (config); if (pool->other_pool) if (!gst_buffer_pool_set_active (pool->other_pool, TRUE)) goto other_pool_failed; /* now, allocate the buffers: */ if (!pclass->start (bpool)) goto start_failed; if (!V4L2_TYPE_IS_OUTPUT (obj->type)) pool->group_released_handler = g_signal_connect_swapped (pool->vallocator, "group-released", G_CALLBACK (gst_v4l2_buffer_pool_group_released), pool); return TRUE; /* ERRORS */ wrong_config: { GST_ERROR_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config); gst_structure_free (config); return FALSE; } no_buffers: { GST_ERROR_OBJECT (pool, "we received %d buffer from device '%s', we want at least %d", min_buffers, obj->videodev, GST_V4L2_MIN_BUFFERS); gst_structure_free (config); return FALSE; } start_failed: { GST_ERROR_OBJECT (pool, "failed to start streaming"); return FALSE; } other_pool_failed: { GST_ERROR_OBJECT (pool, "failed to active the other pool %" GST_PTR_FORMAT, pool->other_pool); return FALSE; } } static gboolean gst_v4l2_buffer_pool_stop (GstBufferPool * bpool) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class); gboolean ret; gint i; GST_DEBUG_OBJECT (pool, "stopping pool"); if (pool->group_released_handler > 0) { g_signal_handler_disconnect (pool->vallocator, pool->group_released_handler); pool->group_released_handler = 0; } if (pool->other_pool) { gst_object_unref (pool->other_pool); pool->other_pool = NULL; } if (!gst_v4l2_buffer_pool_streamoff (pool)) goto streamoff_failed; gst_v4l2_allocator_flush (pool->vallocator); for (i = 0; i < VIDEO_MAX_FRAME; i++) { if (pool->buffers[i]) { GstBuffer *buffer = pool->buffers[i]; pool->buffers[i] = NULL; if (V4L2_TYPE_IS_OUTPUT (pool->obj->type)) gst_buffer_unref (buffer); else pclass->release_buffer (bpool, buffer); g_atomic_int_add (&pool->num_queued, -1); } } ret = GST_BUFFER_POOL_CLASS (parent_class)->stop (bpool); if (ret) { GstV4l2Return vret; vret = gst_v4l2_allocator_stop (pool->vallocator); if (vret == GST_V4L2_BUSY) GST_WARNING_OBJECT (pool, "some buffers are still outstanding"); ret = (vret == GST_V4L2_OK); } return ret; /* ERRORS */ streamoff_failed: GST_ERROR_OBJECT (pool, "device refused to stop streaming"); return FALSE; } static void gst_v4l2_buffer_pool_flush_start (GstBufferPool * bpool) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GST_DEBUG_OBJECT (pool, "start flushing"); gst_poll_set_flushing (pool->poll, TRUE); GST_OBJECT_LOCK (pool); pool->empty = FALSE; g_cond_broadcast (&pool->empty_cond); GST_OBJECT_UNLOCK (pool); if (pool->other_pool) gst_buffer_pool_set_flushing (pool->other_pool, TRUE); } static void gst_v4l2_buffer_pool_flush_stop (GstBufferPool * bpool) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GstV4l2Object *obj = pool->obj; gint i; GST_DEBUG_OBJECT (pool, "stop flushing"); /* If we haven't started streaming yet, simply call streamon */ if (!pool->streaming) goto streamon; if (pool->other_pool) gst_buffer_pool_set_flushing (pool->other_pool, FALSE); if (!gst_v4l2_buffer_pool_streamoff (pool)) goto stop_failed; gst_v4l2_allocator_flush (pool->vallocator); /* Reset our state */ switch (obj->mode) { case GST_V4L2_IO_RW: break; case GST_V4L2_IO_MMAP: case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_DMABUF_IMPORT: { gsize num_allocated; num_allocated = gst_v4l2_allocator_num_allocated (pool->vallocator); for (i = 0; i < num_allocated; i++) { /* Re-enqueue buffers */ if (pool->buffers[i]) { GstBufferPool *bpool = (GstBufferPool *) pool; GstBuffer *buffer = pool->buffers[i]; pool->buffers[i] = NULL; /* Remove qdata, this will unmap any map data in * userptr/dmabuf-import */ gst_mini_object_set_qdata (GST_MINI_OBJECT (buffer), GST_V4L2_IMPORT_QUARK, NULL, NULL); if (V4L2_TYPE_IS_OUTPUT (obj->type)) gst_buffer_unref (buffer); else gst_v4l2_buffer_pool_release_buffer (bpool, buffer); g_atomic_int_add (&pool->num_queued, -1); } } break; } default: g_assert_not_reached (); break; } streamon: /* Start streaming on capture device only */ if (!V4L2_TYPE_IS_OUTPUT (obj->type)) gst_v4l2_buffer_pool_streamon (pool); gst_poll_set_flushing (pool->poll, FALSE); return; /* ERRORS */ stop_failed: { GST_ERROR_OBJECT (pool, "device refused to flush"); } } static GstFlowReturn gst_v4l2_buffer_pool_poll (GstV4l2BufferPool * pool) { gint ret; GST_OBJECT_LOCK (pool); while (pool->empty) g_cond_wait (&pool->empty_cond, GST_OBJECT_GET_LOCK (pool)); GST_OBJECT_UNLOCK (pool); if (!pool->can_poll_device) goto done; GST_LOG_OBJECT (pool, "polling device"); again: ret = gst_poll_wait (pool->poll, GST_CLOCK_TIME_NONE); if (G_UNLIKELY (ret < 0)) { switch (errno) { case EBUSY: goto stopped; case EAGAIN: case EINTR: goto again; case ENXIO: GST_WARNING_OBJECT (pool, "v4l2 device doesn't support polling. Disabling" " using libv4l2 in this case may cause deadlocks"); pool->can_poll_device = FALSE; goto done; default: goto select_error; } } if (gst_poll_fd_has_error (pool->poll, &pool->pollfd)) goto select_error; done: return GST_FLOW_OK; /* ERRORS */ stopped: { GST_DEBUG_OBJECT (pool, "stop called"); return GST_FLOW_FLUSHING; } select_error: { GST_ELEMENT_ERROR (pool->obj->element, RESOURCE, READ, (NULL), ("poll error %d: %s (%d)", ret, g_strerror (errno), errno)); return GST_FLOW_ERROR; } } static GstFlowReturn gst_v4l2_buffer_pool_qbuf (GstV4l2BufferPool * pool, GstBuffer * buf) { GstV4l2MemoryGroup *group = NULL; gint index; if (!gst_v4l2_is_buffer_valid (buf, &group)) { GST_LOG_OBJECT (pool, "unref copied/invalid buffer %p", buf); gst_buffer_unref (buf); return GST_FLOW_OK; } index = group->buffer.index; if (pool->buffers[index] != NULL) goto already_queued; GST_LOG_OBJECT (pool, "queuing buffer %i", index); g_atomic_int_inc (&pool->num_queued); pool->buffers[index] = buf; if (!gst_v4l2_allocator_qbuf (pool->vallocator, group)) goto queue_failed; GST_OBJECT_LOCK (pool); pool->empty = FALSE; g_cond_signal (&pool->empty_cond); GST_OBJECT_UNLOCK (pool); return GST_FLOW_OK; already_queued: { GST_ERROR_OBJECT (pool, "the buffer %i was already queued", index); return GST_FLOW_ERROR; } queue_failed: { GST_ERROR_OBJECT (pool, "could not queue a buffer %i", index); /* Mark broken buffer to the allocator */ GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_TAG_MEMORY); g_atomic_int_add (&pool->num_queued, -1); pool->buffers[index] = NULL; return GST_FLOW_ERROR; } } static GstFlowReturn gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer) { GstFlowReturn res; GstBuffer *outbuf; GstV4l2Object *obj = pool->obj; GstClockTime timestamp; GstV4l2MemoryGroup *group; gint i; if ((res = gst_v4l2_buffer_pool_poll (pool)) != GST_FLOW_OK) goto poll_failed; GST_LOG_OBJECT (pool, "dequeueing a buffer"); group = gst_v4l2_allocator_dqbuf (pool->vallocator); if (group == NULL) goto dqbuf_failed; /* get our GstBuffer with that index from the pool, if the buffer was * outstanding we have a serious problem. */ outbuf = pool->buffers[group->buffer.index]; if (outbuf == NULL) goto no_buffer; /* mark the buffer outstanding */ pool->buffers[group->buffer.index] = NULL; if (g_atomic_int_dec_and_test (&pool->num_queued)) { GST_OBJECT_LOCK (pool); pool->empty = TRUE; GST_OBJECT_UNLOCK (pool); } timestamp = GST_TIMEVAL_TO_TIME (group->buffer.timestamp); #ifndef GST_DISABLE_GST_DEBUG for (i = 0; i < group->n_mem; i++) { GST_LOG_OBJECT (pool, "dequeued buffer %p seq:%d (ix=%d), mem %p used %d, plane=%d, flags %08x, ts %" GST_TIME_FORMAT ", pool-queued=%d, buffer=%p", outbuf, group->buffer.sequence, group->buffer.index, group->mem[i], group->planes[i].bytesused, i, group->buffer.flags, GST_TIME_ARGS (timestamp), pool->num_queued, outbuf); } #endif /* set top/bottom field first if v4l2_buffer has the information */ if (group->buffer.field == V4L2_FIELD_INTERLACED_TB) { GST_BUFFER_FLAG_SET (outbuf, GST_VIDEO_BUFFER_FLAG_INTERLACED); GST_BUFFER_FLAG_SET (outbuf, GST_VIDEO_BUFFER_FLAG_TFF); } else if (group->buffer.field == V4L2_FIELD_INTERLACED_BT) { GST_BUFFER_FLAG_SET (outbuf, GST_VIDEO_BUFFER_FLAG_INTERLACED); GST_BUFFER_FLAG_UNSET (outbuf, GST_VIDEO_BUFFER_FLAG_TFF); } else { GST_BUFFER_FLAG_UNSET (outbuf, GST_VIDEO_BUFFER_FLAG_INTERLACED); GST_BUFFER_FLAG_UNSET (outbuf, GST_VIDEO_BUFFER_FLAG_TFF); } if (GST_VIDEO_INFO_FORMAT (&obj->info) == GST_VIDEO_FORMAT_ENCODED) { if (group->buffer.flags & V4L2_BUF_FLAG_KEYFRAME) GST_BUFFER_FLAG_UNSET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT); else GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT); } GST_BUFFER_TIMESTAMP (outbuf) = timestamp; *buffer = outbuf; return GST_FLOW_OK; /* ERRORS */ poll_failed: { GST_DEBUG_OBJECT (pool, "poll error %s", gst_flow_get_name (res)); return res; } dqbuf_failed: { return GST_FLOW_ERROR; } no_buffer: { GST_ERROR_OBJECT (pool, "No free buffer found in the pool at index %d.", group->buffer.index); return GST_FLOW_ERROR; } } static GstFlowReturn gst_v4l2_buffer_pool_acquire_buffer (GstBufferPool * bpool, GstBuffer ** buffer, GstBufferPoolAcquireParams * params) { GstFlowReturn ret; GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class); GstV4l2Object *obj = pool->obj; GST_DEBUG_OBJECT (pool, "acquire"); /* If this is being called to resurect a lost buffer */ if (params && params->flags & GST_V4L2_POOL_ACQUIRE_FLAG_RESURECT) { ret = pclass->acquire_buffer (bpool, buffer, params); goto done; } switch (obj->type) { case V4L2_BUF_TYPE_VIDEO_CAPTURE: case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE: /* capture, This function should return a buffer with new captured data */ switch (obj->mode) { case GST_V4L2_IO_RW: { /* take empty buffer from the pool */ ret = pclass->acquire_buffer (bpool, buffer, params); break; } case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_MMAP: { /* just dequeue a buffer, we basically use the queue of v4l2 as the * storage for our buffers. This function does poll first so we can * interrupt it fine. */ ret = gst_v4l2_buffer_pool_dqbuf (pool, buffer); if (G_UNLIKELY (ret != GST_FLOW_OK)) goto done; break; } case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF_IMPORT: { /* dequeue filled buffer */ ret = gst_v4l2_buffer_pool_dqbuf (pool, buffer); break; } default: ret = GST_FLOW_ERROR; g_assert_not_reached (); break; } break; case V4L2_BUF_TYPE_VIDEO_OUTPUT: case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE: /* playback, This function should return an empty buffer */ switch (obj->mode) { case GST_V4L2_IO_RW: /* get an empty buffer */ ret = pclass->acquire_buffer (bpool, buffer, params); break; case GST_V4L2_IO_MMAP: case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF_IMPORT: /* get a free unqueued buffer */ ret = pclass->acquire_buffer (bpool, buffer, params); break; default: ret = GST_FLOW_ERROR; g_assert_not_reached (); break; } break; default: ret = GST_FLOW_ERROR; g_assert_not_reached (); break; } done: return ret; } static void gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool, GstBuffer * buffer) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class); GstV4l2Object *obj = pool->obj; GST_DEBUG_OBJECT (pool, "release buffer %p", buffer); switch (obj->type) { case V4L2_BUF_TYPE_VIDEO_CAPTURE: case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE: /* capture, put the buffer back in the queue so that we can refill it * later. */ switch (obj->mode) { case GST_V4L2_IO_RW: /* release back in the pool */ pclass->release_buffer (bpool, buffer); break; case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_MMAP: case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF_IMPORT: { if (gst_v4l2_is_buffer_valid (buffer, NULL)) { /* queue back in the device */ if (pool->other_pool) gst_v4l2_buffer_pool_prepare_buffer (pool, buffer, NULL); if (gst_v4l2_buffer_pool_qbuf (pool, buffer) != GST_FLOW_OK) pclass->release_buffer (bpool, buffer); } else { /* Simply release invalide/modified buffer, the allocator will * give it back later */ GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY); pclass->release_buffer (bpool, buffer); } break; } default: g_assert_not_reached (); break; } break; case V4L2_BUF_TYPE_VIDEO_OUTPUT: case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE: switch (obj->mode) { case GST_V4L2_IO_RW: /* release back in the pool */ pclass->release_buffer (bpool, buffer); break; case GST_V4L2_IO_MMAP: case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF_IMPORT: { GstV4l2MemoryGroup *group; guint index; if (!gst_v4l2_is_buffer_valid (buffer, &group)) { /* Simply release invalide/modified buffer, the allocator will * give it back later */ GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY); pclass->release_buffer (bpool, buffer); break; } index = group->buffer.index; if (pool->buffers[index] == NULL) { GST_LOG_OBJECT (pool, "buffer %u not queued, putting on free list", index); /* Remove qdata, this will unmap any map data in userptr */ gst_mini_object_set_qdata (GST_MINI_OBJECT (buffer), GST_V4L2_IMPORT_QUARK, NULL, NULL); /* reset to default size */ gst_v4l2_allocator_reset_group (pool->vallocator, group); /* playback, put the buffer back in the queue to refill later. */ pclass->release_buffer (bpool, buffer); } else { /* We keep a ref on queued buffer, so this should never happen */ g_assert_not_reached (); } break; } default: g_assert_not_reached (); break; } break; default: g_assert_not_reached (); break; } } static void gst_v4l2_buffer_pool_finalize (GObject * object) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (object); gint i; for (i = 0; i < VIDEO_MAX_FRAME; i++) { if (pool->buffers[i]) gst_buffer_replace (&(pool->buffers[i]), NULL); } if (pool->video_fd >= 0) v4l2_close (pool->video_fd); gst_poll_free (pool->poll); if (pool->vallocator) gst_object_unref (pool->vallocator); if (pool->allocator) gst_object_unref (pool->allocator); if (pool->other_pool) gst_object_unref (pool->other_pool); /* FIXME Is this required to keep around ? */ gst_object_unref (pool->obj->element); /* FIXME have we done enough here ? */ G_OBJECT_CLASS (parent_class)->finalize (object); } static void gst_v4l2_buffer_pool_init (GstV4l2BufferPool * pool) { pool->poll = gst_poll_new (TRUE); pool->can_poll_device = TRUE; g_cond_init (&pool->empty_cond); pool->empty = TRUE; } static void gst_v4l2_buffer_pool_class_init (GstV4l2BufferPoolClass * klass) { GObjectClass *object_class = G_OBJECT_CLASS (klass); GstBufferPoolClass *bufferpool_class = GST_BUFFER_POOL_CLASS (klass); object_class->finalize = gst_v4l2_buffer_pool_finalize; bufferpool_class->start = gst_v4l2_buffer_pool_start; bufferpool_class->stop = gst_v4l2_buffer_pool_stop; bufferpool_class->set_config = gst_v4l2_buffer_pool_set_config; bufferpool_class->alloc_buffer = gst_v4l2_buffer_pool_alloc_buffer; bufferpool_class->acquire_buffer = gst_v4l2_buffer_pool_acquire_buffer; bufferpool_class->release_buffer = gst_v4l2_buffer_pool_release_buffer; bufferpool_class->flush_start = gst_v4l2_buffer_pool_flush_start; bufferpool_class->flush_stop = gst_v4l2_buffer_pool_flush_stop; } /** * gst_v4l2_buffer_pool_new: * @obj: the v4l2 object owning the pool * * Construct a new buffer pool. * * Returns: the new pool, use gst_object_unref() to free resources */ GstBufferPool * gst_v4l2_buffer_pool_new (GstV4l2Object * obj, GstCaps * caps) { GstV4l2BufferPool *pool; GstStructure *config; gchar *name, *parent_name; gint fd; fd = v4l2_dup (obj->video_fd); if (fd < 0) goto dup_failed; /* setting a significant unique name */ parent_name = gst_object_get_name (GST_OBJECT (obj->element)); name = g_strconcat (parent_name, ":", "pool:", V4L2_TYPE_IS_OUTPUT (obj->type) ? "sink" : "src", NULL); g_free (parent_name); pool = (GstV4l2BufferPool *) g_object_new (GST_TYPE_V4L2_BUFFER_POOL, "name", name, NULL); g_free (name); gst_poll_fd_init (&pool->pollfd); pool->pollfd.fd = fd; gst_poll_add_fd (pool->poll, &pool->pollfd); if (V4L2_TYPE_IS_OUTPUT (obj->type)) gst_poll_fd_ctl_write (pool->poll, &pool->pollfd, TRUE); else gst_poll_fd_ctl_read (pool->poll, &pool->pollfd, TRUE); pool->video_fd = fd; pool->obj = obj; pool->can_poll_device = TRUE; pool->vallocator = gst_v4l2_allocator_new (GST_OBJECT (pool), obj->video_fd, &obj->format); if (pool->vallocator == NULL) goto allocator_failed; gst_object_ref (obj->element); config = gst_buffer_pool_get_config (GST_BUFFER_POOL_CAST (pool)); gst_buffer_pool_config_set_params (config, caps, obj->info.size, 0, 0); /* This will simply set a default config, but will not configure the pool * because min and max are not valid */ gst_buffer_pool_set_config (GST_BUFFER_POOL_CAST (pool), config); return GST_BUFFER_POOL (pool); /* ERRORS */ dup_failed: { GST_ERROR ("failed to dup fd %d (%s)", errno, g_strerror (errno)); return NULL; } allocator_failed: { GST_ERROR_OBJECT (pool, "Failed to create V4L2 allocator"); return NULL; } } static GstFlowReturn gst_v4l2_do_read (GstV4l2BufferPool * pool, GstBuffer * buf) { GstFlowReturn res; GstV4l2Object *obj = pool->obj; gint amount; GstMapInfo map; gint toread; toread = obj->info.size; GST_LOG_OBJECT (pool, "reading %d bytes into buffer %p", toread, buf); gst_buffer_map (buf, &map, GST_MAP_WRITE); do { if ((res = gst_v4l2_buffer_pool_poll (pool)) != GST_FLOW_OK) goto poll_error; amount = v4l2_read (obj->video_fd, map.data, toread); if (amount == toread) { break; } else if (amount == -1) { if (errno == EAGAIN || errno == EINTR) { continue; } else goto read_error; } else { /* short reads can happen if a signal interrupts the read */ continue; } } while (TRUE); GST_LOG_OBJECT (pool, "read %d bytes", amount); gst_buffer_unmap (buf, &map); gst_buffer_resize (buf, 0, amount); return GST_FLOW_OK; /* ERRORS */ poll_error: { GST_DEBUG ("poll error %s", gst_flow_get_name (res)); goto cleanup; } read_error: { GST_ELEMENT_ERROR (obj->element, RESOURCE, READ, (_("Error reading %d bytes from device '%s'."), toread, obj->videodev), GST_ERROR_SYSTEM); res = GST_FLOW_ERROR; goto cleanup; } cleanup: { gst_buffer_unmap (buf, &map); gst_buffer_resize (buf, 0, 0); return res; } } /** * gst_v4l2_buffer_pool_process: * @bpool: a #GstBufferPool * @buf: a #GstBuffer, maybe be replaced * * Process @buf in @bpool. For capture devices, this functions fills @buf with * data from the device. For output devices, this functions send the contents of * @buf to the device for playback. * * Returns: %GST_FLOW_OK on success. */ GstFlowReturn gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf) { GstFlowReturn ret = GST_FLOW_OK; GstBufferPool *bpool = GST_BUFFER_POOL_CAST (pool); GstV4l2Object *obj = pool->obj; GST_DEBUG_OBJECT (pool, "process buffer %p", buf); g_return_val_if_fail (gst_buffer_pool_is_active (bpool), GST_FLOW_ERROR); if (GST_BUFFER_POOL_IS_FLUSHING (pool)) return GST_FLOW_FLUSHING; switch (obj->type) { case V4L2_BUF_TYPE_VIDEO_CAPTURE: case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE: /* capture */ switch (obj->mode) { case GST_V4L2_IO_RW: /* capture into the buffer */ ret = gst_v4l2_do_read (pool, *buf); break; case GST_V4L2_IO_MMAP: case GST_V4L2_IO_DMABUF: { GstBuffer *tmp; if ((*buf)->pool == bpool) { if (gst_buffer_get_size (*buf) == 0) goto eos; /* start copying buffers when we are running low on buffers */ if (g_atomic_int_get (&pool->num_queued) < pool->copy_threshold) { GstBuffer *copy; if (GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP)) { if (gst_buffer_pool_acquire_buffer (bpool, ©, NULL) == GST_FLOW_OK) { gst_v4l2_buffer_pool_release_buffer (bpool, copy); goto done; } } /* copy the buffer */ copy = gst_buffer_copy_region (*buf, GST_BUFFER_COPY_ALL | GST_BUFFER_COPY_DEEP, 0, -1); GST_LOG_OBJECT (pool, "copy buffer %p->%p", *buf, copy); /* and requeue so that we can continue capturing */ gst_buffer_unref (*buf); *buf = copy; } /* nothing, data was inside the buffer when we did _acquire() */ goto done; } /* buffer not from our pool, grab a frame and copy it into the target */ if ((ret = gst_v4l2_buffer_pool_dqbuf (pool, &tmp)) != GST_FLOW_OK) goto done; /* An empty buffer on capture indicates the end of stream */ if (gst_buffer_get_size (tmp) == 0) { gst_v4l2_buffer_pool_release_buffer (bpool, tmp); goto eos; } ret = gst_v4l2_buffer_pool_copy_buffer (pool, *buf, tmp); /* an queue the buffer again after the copy */ gst_v4l2_buffer_pool_release_buffer (bpool, tmp); if (ret != GST_FLOW_OK) goto copy_failed; break; } case GST_V4L2_IO_USERPTR: { struct UserPtrData *data; /* Replace our buffer with downstream allocated buffer */ data = gst_mini_object_steal_qdata (GST_MINI_OBJECT (*buf), GST_V4L2_IMPORT_QUARK); gst_buffer_replace (buf, data->buffer); _unmap_userptr_frame (data); break; } case GST_V4L2_IO_DMABUF_IMPORT: { GstBuffer *tmp; /* Replace our buffer with downstream allocated buffer */ tmp = gst_mini_object_steal_qdata (GST_MINI_OBJECT (*buf), GST_V4L2_IMPORT_QUARK); gst_buffer_replace (buf, tmp); gst_buffer_unref (tmp); break; } default: g_assert_not_reached (); break; } break; case V4L2_BUF_TYPE_VIDEO_OUTPUT: case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE: /* playback */ switch (obj->mode) { case GST_V4L2_IO_RW: /* FIXME, do write() */ GST_WARNING_OBJECT (pool, "implement write()"); break; case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF_IMPORT: case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_MMAP: { GstBuffer *to_queue = NULL; GstV4l2MemoryGroup *group; gint index; if ((*buf)->pool != bpool) goto copying; if (!gst_v4l2_is_buffer_valid (*buf, &group)) goto copying; index = group->buffer.index; GST_LOG_OBJECT (pool, "processing buffer %i from our pool", index); index = group->buffer.index; if (pool->buffers[index] != NULL) { GST_LOG_OBJECT (pool, "buffer %i already queued, copying", index); goto copying; } /* we can queue directly */ to_queue = gst_buffer_ref (*buf); copying: if (to_queue == NULL) { GstBufferPoolAcquireParams params = { 0 }; GST_LOG_OBJECT (pool, "alloc buffer from our pool"); /* this can return EOS if all buffers are outstanding which would * be strange because we would expect the upstream element to have * allocated them and returned to us.. */ params.flags = GST_BUFFER_POOL_ACQUIRE_FLAG_DONTWAIT; ret = gst_buffer_pool_acquire_buffer (bpool, &to_queue, ¶ms); if (ret != GST_FLOW_OK) goto acquire_failed; ret = gst_v4l2_buffer_pool_prepare_buffer (pool, to_queue, *buf); if (ret != GST_FLOW_OK) { gst_buffer_unref (to_queue); goto prepare_failed; } } if ((ret = gst_v4l2_buffer_pool_qbuf (pool, to_queue)) != GST_FLOW_OK) goto queue_failed; /* if we are not streaming yet (this is the first buffer, start * streaming now */ if (!gst_v4l2_buffer_pool_streamon (pool)) { gst_buffer_unref (to_queue); goto start_failed; } if (g_atomic_int_get (&pool->num_queued) >= pool->min_latency) { GstBuffer *out; /* all buffers are queued, try to dequeue one and release it back * into the pool so that _acquire can get to it again. */ ret = gst_v4l2_buffer_pool_dqbuf (pool, &out); if (ret == GST_FLOW_OK) /* release the rendered buffer back into the pool. This wakes up any * thread waiting for a buffer in _acquire(). */ gst_buffer_unref (out); } break; } default: g_assert_not_reached (); break; } break; default: g_assert_not_reached (); break; } done: return ret; /* ERRORS */ copy_failed: { GST_ERROR_OBJECT (pool, "failed to copy buffer"); return ret; } eos: { GST_DEBUG_OBJECT (pool, "end of stream reached"); return GST_FLOW_EOS; } acquire_failed: { if (ret == GST_FLOW_FLUSHING) GST_DEBUG_OBJECT (pool, "flushing"); else GST_WARNING_OBJECT (pool, "failed to acquire a buffer: %s", gst_flow_get_name (ret)); return ret; } prepare_failed: { GST_ERROR_OBJECT (pool, "failed to prepare data"); return ret; } queue_failed: { GST_ERROR_OBJECT (pool, "failed to queue buffer"); return ret; } start_failed: { GST_ERROR_OBJECT (pool, "failed to start streaming"); return GST_FLOW_ERROR; } } void gst_v4l2_buffer_pool_set_other_pool (GstV4l2BufferPool * pool, GstBufferPool * other_pool) { g_return_if_fail (!gst_buffer_pool_is_active (GST_BUFFER_POOL (pool))); if (pool->other_pool) gst_object_unref (pool->other_pool); pool->other_pool = gst_object_ref (other_pool); }