/* 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); #define GST_CAT_DEFAULT v4l2_debug /* * 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_v4l2_memory (mem)) { GstV4l2Memory *vmem = (GstV4l2Memory *) mem; valid = TRUE; if (group) *group = vmem->group; } done: return valid; } 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; GstVideoAlignment *align; obj = pool->obj; info = &obj->info; align = &obj->align; 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: /* TODO group = gst_v4l2_allocator_alloc_dmabuf (pool->vallocator); */ break; case GST_V4L2_IO_USERPTR: 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 && info->finfo) { const GstVideoFormatInfo *finfo = info->finfo; gsize offset[GST_VIDEO_MAX_PLANES]; gint width, height, n_gst_planes, offs, i, stride[GST_VIDEO_MAX_PLANES]; width = GST_VIDEO_INFO_WIDTH (info); height = GST_VIDEO_INFO_HEIGHT (info); /* n_gst_planes is the number of planes * (RGB: 1, YUY2: 1, NV12: 2, I420: 3) * It's greater or equal than the number of v4l2 planes. */ n_gst_planes = GST_VIDEO_INFO_N_PLANES (info); /* the basic are common between MPLANE mode and non MPLANE mode * except a special case inside the loop at the end */ offs = 0; for (i = 0; i < n_gst_planes; i++) { GST_DEBUG_OBJECT (pool, "adding video meta, bytesperline %d", obj->bytesperline[i]); offset[i] = offs; if (GST_VIDEO_FORMAT_INFO_IS_TILED (finfo)) { guint x_tiles, y_tiles, ws, hs, tile_height; ws = GST_VIDEO_FORMAT_INFO_TILE_WS (finfo); hs = GST_VIDEO_FORMAT_INFO_TILE_HS (finfo); tile_height = 1 << hs; x_tiles = obj->bytesperline[i] >> ws; y_tiles = GST_VIDEO_FORMAT_INFO_SCALE_HEIGHT (finfo, i, GST_ROUND_UP_N (height, tile_height) >> hs); stride[i] = GST_VIDEO_TILE_MAKE_STRIDE (x_tiles, y_tiles); } else { stride[i] = obj->bytesperline[i]; } /* when using multiplanar mode and if there is more then one v4l * plane for each gst plane */ if (V4L2_TYPE_IS_MULTIPLANAR (obj->type) && group->n_mem > 1) /* non_contiguous case here so we have to make sure that gst goes to the * next plane (using default gstvideometa.c::default_map). * And the next plane is after length bytes of the previous one from * the gst buffer point of view. */ offs += gst_memory_get_sizes (group->mem[i], NULL, NULL); else offs += obj->bytesperline[i] * GST_VIDEO_FORMAT_INFO_SCALE_HEIGHT (finfo, i, height); } gst_buffer_add_video_meta_full (newbuf, GST_VIDEO_FRAME_FLAG_NONE, GST_VIDEO_INFO_FORMAT (info), width, height, n_gst_planes, offset, stride); } if (pool->add_cropmeta) { GstVideoCropMeta *crop; crop = gst_buffer_add_video_crop_meta (newbuf); crop->x = align->padding_left; crop->y = align->padding_top; crop->width = info->width; crop->width = info->height; } pool->num_allocated++; *buffer = newbuf; return GST_FLOW_OK; /* ERRORS */ allocation_failed: { GST_WARNING ("Failed to allocated buffer"); return GST_FLOW_EOS; } } 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); pool->add_cropmeta = gst_buffer_pool_config_has_option (config, GST_V4L2_BUFFER_POOL_OPTION_CROP_META); if (!pool->add_videometa && obj->need_video_meta) goto missing_video_api; if (!pool->add_cropmeta && obj->need_crop_meta) goto missing_crop_api; /* 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_RW: default: pool->allocator = g_object_ref (allocator); pool->params = params; /* No need to change the configuration */ goto done; 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 (updated) gst_buffer_pool_config_set_params (config, caps, size, min_buffers, max_buffers); 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 */ missing_video_api: { GST_ERROR_OBJECT (pool, "missing GstVideoMeta API in config"); return FALSE; } missing_crop_api: { GST_ERROR_OBJECT (pool, "missing GstVideoCropMeta API"); return FALSE; } wrong_config: { GST_ERROR_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config); return FALSE; } } static gboolean start_streaming (GstV4l2BufferPool * pool) { GstV4l2Object *obj = pool->obj; switch (obj->mode) { case GST_V4L2_IO_RW: break; case GST_V4L2_IO_MMAP: case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF: GST_DEBUG_OBJECT (pool, "STREAMON"); if (v4l2_ioctl (pool->video_fd, VIDIOC_STREAMON, &obj->type) < 0) goto start_failed; break; default: g_assert_not_reached (); break; } pool->streaming = TRUE; return TRUE; /* ERRORS */ start_failed: { GST_ERROR_OBJECT (pool, "error with STREAMON %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 = 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); GstV4l2Object *obj = pool->obj; GstStructure *config; GstCaps *caps; guint size, min_buffers, max_buffers; guint num_buffers = 0, copy_threshold = 0; config = gst_buffer_pool_get_config (bpool); if (!gst_buffer_pool_config_get_params (config, &caps, &size, &min_buffers, &max_buffers)) goto wrong_config; switch (obj->mode) { case GST_V4L2_IO_RW: /* this value also instructs the latency calculation to have min_buffers * frame latency max */ num_buffers = min_buffers; break; case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_MMAP: { guint count; if (GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP)) { num_buffers = min_buffers; } else { num_buffers = max_buffers; } /* first, lets request buffers, and see how many we can get: */ GST_DEBUG_OBJECT (pool, "requesting %d MMAP buffers", num_buffers); count = gst_v4l2_allocator_start (pool->vallocator, num_buffers, V4L2_MEMORY_MMAP); if (count < GST_V4L2_MIN_BUFFERS) { num_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 != num_buffers) { GST_WARNING_OBJECT (pool, "using %u buffers instead of %u", count, num_buffers); num_buffers = count; copy_threshold = MAX (GST_V4L2_MIN_BUFFERS, obj->min_buffers_for_capture); /* Ensure GstBufferPool don't expect initial minimum */ if (min_buffers > count) min_buffers = count; } break; } case GST_V4L2_IO_USERPTR: default: num_buffers = 0; copy_threshold = 0; g_assert_not_reached (); break; } pool->size = size; pool->copy_threshold = copy_threshold; pool->num_buffers = num_buffers; pool->num_allocated = 0; pool->num_queued = 0; gst_buffer_pool_config_set_params (config, caps, size, min_buffers, max_buffers); GST_BUFFER_POOL_CLASS (parent_class)->set_config (bpool, config); gst_structure_free (config); /* now, allocate the buffers: */ if (!GST_BUFFER_POOL_CLASS (parent_class)->start (bpool)) goto start_failed; /* we can start capturing now, we wait for the playback case until we queued * the first buffer */ if (!V4L2_TYPE_IS_OUTPUT (obj->type)) if (!start_streaming (pool)) 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); gst_poll_set_flushing (obj->poll, FALSE); return TRUE; /* ERRORS */ wrong_config: { GST_ERROR_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config); return FALSE; } no_buffers: { GST_ERROR_OBJECT (pool, "we received %d buffer from device '%s', we want at least %d", num_buffers, obj->videodev, GST_V4L2_MIN_BUFFERS); return FALSE; } start_failed: { GST_ERROR_OBJECT (pool, "failed to start streaming"); return FALSE; } } static gboolean stop_streaming (GstV4l2BufferPool * pool) { GstV4l2Object *obj = pool->obj; gint i; GST_DEBUG_OBJECT (pool, "stopping stream"); gst_poll_set_flushing (obj->poll, TRUE); if (!pool->streaming) { /* it avoid error: STREAMOFF 22 (Invalid argument) when * attempting to stop a stream not previously started */ GST_DEBUG_OBJECT (pool, "no need to stop, was not previously started"); return TRUE; } switch (obj->mode) { case GST_V4L2_IO_RW: break; case GST_V4L2_IO_MMAP: case GST_V4L2_IO_USERPTR: case GST_V4L2_IO_DMABUF: GST_DEBUG_OBJECT (pool, "STREAMOFF"); if (v4l2_ioctl (pool->video_fd, VIDIOC_STREAMOFF, &obj->type) < 0) goto stop_failed; gst_v4l2_allocator_flush (pool->vallocator); for (i = 0; i < pool->num_allocated; i++) { if (pool->buffers[i]) { GstBufferPool *bpool = (GstBufferPool *) pool; GstBuffer *buffer = pool->buffers[i]; pool->buffers[i] = NULL; pool->num_queued--; if (V4L2_TYPE_IS_OUTPUT (obj->type)) gst_buffer_unref (buffer); else /* Give back the outstanding buffer to the pool */ GST_BUFFER_POOL_CLASS (parent_class)->release_buffer (bpool, buffer); } } g_return_val_if_fail (pool->num_queued == 0, FALSE); break; default: g_return_val_if_reached (FALSE); break; } pool->streaming = FALSE; return TRUE; /* ERRORS */ stop_failed: { GST_ERROR_OBJECT (pool, "error with STREAMOFF %d (%s)", errno, g_strerror (errno)); return FALSE; } } static gboolean gst_v4l2_buffer_pool_stop (GstBufferPool * bpool) { gboolean ret; GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); GstV4l2Object *obj = pool->obj; 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; } gst_poll_set_flushing (obj->poll, TRUE); if (!stop_streaming (pool)) goto stop_failed; 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, "allocated buffer need to be reclaimed"); /* FIXME deal with reclaiming */ } else if (vret == GST_V4L2_ERROR) { ret = FALSE; } } return ret; /* ERRORS */ stop_failed: { GST_ERROR_OBJECT (pool, "error with STREAMOFF %d (%s)", errno, g_strerror (errno)); return FALSE; } } static GstFlowReturn gst_v4l2_object_poll (GstV4l2Object * v4l2object) { gint ret; if (v4l2object->can_poll_device) { GST_LOG_OBJECT (v4l2object->element, "polling device"); ret = gst_poll_wait (v4l2object->poll, GST_CLOCK_TIME_NONE); if (G_UNLIKELY (ret < 0)) { if (errno == EBUSY) goto stopped; if (errno == ENXIO) { GST_WARNING_OBJECT (v4l2object->element, "v4l2 device doesn't support polling. Disabling"); v4l2object->can_poll_device = FALSE; } else { if (errno != EAGAIN && errno != EINTR) goto select_error; } } } return GST_FLOW_OK; /* ERRORS */ stopped: { GST_DEBUG ("stop called"); return GST_FLOW_FLUSHING; } select_error: { GST_ELEMENT_ERROR (v4l2object->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); if (!gst_v4l2_allocator_qbuf (pool->vallocator, group)) goto queue_failed; pool->buffers[index] = buf; pool->num_queued++; return GST_FLOW_OK; already_queued: { GST_ERROR_OBJECT (pool, "the buffer %i was already queued", index); gst_buffer_unref (buf); return GST_FLOW_ERROR; } queue_failed: { GST_ERROR_OBJECT (pool, "could not queue a buffer %i", index); /* Return broken buffer to the allocator */ GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_TAG_MEMORY); gst_buffer_unref (buf); 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_object_poll (obj)) != 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; pool->num_queued--; 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); GstV4l2Object *obj = pool->obj; GST_DEBUG_OBJECT (pool, "acquire"); if (GST_BUFFER_POOL_IS_FLUSHING (bpool)) goto flushing; 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 = GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool, buffer, params); break; case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_MMAP: /* If this is being called to resurect a lost buffer */ if (params && params->flags & GST_V4L2_POOL_ACQUIRE_FLAG_RESURECT) { ret = GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool, buffer, params); break; } /* 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; /* start copying buffers when we are running low on buffers */ if (pool->num_queued < pool->copy_threshold) { GstBuffer *copy; if (GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP)) { if (GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool, ©, params) == GST_FLOW_OK) { gst_v4l2_buffer_pool_release_buffer (bpool, copy); break; } } /* copy the buffer */ copy = gst_buffer_copy_region (*buffer, GST_BUFFER_COPY_ALL | GST_BUFFER_COPY_DEEP, 0, -1); GST_LOG_OBJECT (pool, "copy buffer %p->%p", *buffer, copy); /* and requeue so that we can continue capturing */ ret = gst_v4l2_buffer_pool_qbuf (pool, *buffer); *buffer = copy; } break; case GST_V4L2_IO_USERPTR: 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 = GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool, buffer, params); break; case GST_V4L2_IO_MMAP: /* get a free unqueued buffer */ ret = GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool, buffer, params); break; case GST_V4L2_IO_USERPTR: default: ret = GST_FLOW_ERROR; g_assert_not_reached (); break; } break; default: ret = GST_FLOW_ERROR; g_assert_not_reached (); break; } done: return ret; /* ERRORS */ flushing: { GST_DEBUG_OBJECT (pool, "We are flushing"); return GST_FLOW_FLUSHING; } } static void gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool, GstBuffer * buffer) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool); 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 */ GST_BUFFER_POOL_CLASS (parent_class)->release_buffer (bpool, buffer); break; case GST_V4L2_IO_DMABUF: case GST_V4L2_IO_MMAP: { if (gst_v4l2_is_buffer_valid (buffer, NULL)) { /* queue back in the device */ gst_v4l2_buffer_pool_qbuf (pool, buffer); } else { /* Simply release invalide/modified buffer, the allocator will * give it back later */ GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY); GST_BUFFER_POOL_CLASS (parent_class)->release_buffer (bpool, buffer); } break; } case GST_V4L2_IO_USERPTR: 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 */ GST_BUFFER_POOL_CLASS (parent_class)->release_buffer (bpool, buffer); break; case GST_V4L2_IO_MMAP: { 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); GST_BUFFER_POOL_CLASS (parent_class)->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); /* reset to default size */ gst_v4l2_allocator_reset_size (pool->vallocator, group); /* playback, put the buffer back in the queue to refill later. */ GST_BUFFER_POOL_CLASS (parent_class)->release_buffer (bpool, buffer); } else { /* the buffer is queued in the device but maybe not played yet. We just * leave it there and not make it available for future calls to acquire * for now. The buffer will be dequeued and reused later. */ GST_LOG_OBJECT (pool, "buffer %u is queued", index); } break; } case GST_V4L2_IO_USERPTR: 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); if (pool->vallocator) gst_object_unref (pool->vallocator); if (pool->allocator) gst_object_unref (pool->allocator); /* 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) { } 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; } /** * 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); pool->video_fd = fd; pool->obj = obj; pool->vallocator = gst_v4l2_allocator_new (GST_OBJECT (pool), obj->video_fd, &obj->format); 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->sizeimage, 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; } } static GstFlowReturn gst_v4l2_do_read (GstV4l2BufferPool * pool, GstBuffer * buf) { GstFlowReturn res; GstV4l2Object *obj = pool->obj; gint amount; GstMapInfo map; gint toread; toread = obj->sizeimage; 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_object_poll (obj)) != 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 * * 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); 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: { GstBuffer *tmp; if (buf->pool == bpool) { if (gst_buffer_get_size (buf) == 0) goto eos; else /* 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_buffer_unref (tmp); goto eos; } if (!gst_v4l2_object_copy (obj, buf, tmp)) goto copy_failed; /* an queue the buffer again after the copy */ if ((ret = gst_v4l2_buffer_pool_qbuf (pool, tmp)) != GST_FLOW_OK) goto done; break; } case GST_V4L2_IO_USERPTR: 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_DMABUF: case GST_V4L2_IO_MMAP: { GstBuffer *to_queue; if (buf->pool == bpool) { /* nothing, we can queue directly */ to_queue = gst_buffer_ref (buf); GST_LOG_OBJECT (pool, "processing buffer from our pool"); } else { 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; /* copy into it and queue */ if (!gst_v4l2_object_copy (obj, to_queue, buf)) goto copy_failed; } if ((ret = gst_v4l2_buffer_pool_qbuf (pool, to_queue)) != GST_FLOW_OK) goto done; /* if we are not streaming yet (this is the first buffer, start * streaming now */ if (!pool->streaming) if (!start_streaming (pool)) goto start_failed; if (pool->num_queued == pool->num_allocated) { 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) { gst_buffer_unref (to_queue); goto done; } /* release the rendered buffer back into the pool. This wakes up any * thread waiting for a buffer in _acquire(). If the buffer still has * a pool then this will happen when the refcount reaches 0 */ if (!out->pool) gst_v4l2_buffer_pool_release_buffer (bpool, out); } gst_buffer_unref (to_queue); break; } case GST_V4L2_IO_USERPTR: default: g_assert_not_reached (); break; } break; default: g_assert_not_reached (); break; } done: return ret; /* ERRORS */ acquire_failed: { GST_WARNING_OBJECT (obj->element, "failed to acquire a buffer: %s", gst_flow_get_name (ret)); return ret; } copy_failed: { GST_ERROR_OBJECT (obj->element, "failed to copy data"); return GST_FLOW_ERROR; } start_failed: { GST_ERROR_OBJECT (obj->element, "failed to start streaming"); return GST_FLOW_ERROR; } eos: { GST_DEBUG_OBJECT (obj->element, "end of stream reached"); return GST_FLOW_EOS; } } /** * gst_v4l2_buffer_pool_flush: * @bpool: a #GstBufferPool * * First, set obj->poll to be flushing * Call STREAMOFF to clear QUEUED flag on every driver buffers. * Then release all buffers that are in pool->buffers array. * Finally call STREAMON if CAPTURE type * The caller is responsible to unset flushing on obj->pool * * Returns: TRUE on success. */ gboolean gst_v4l2_buffer_pool_flush (GstV4l2BufferPool * pool) { GstV4l2Object *obj = pool->obj; GST_DEBUG_OBJECT (pool, "flush"); stop_streaming (pool); /* we can start capturing now, we wait for the playback * case until we queued the first buffer */ if (!V4L2_TYPE_IS_OUTPUT (obj->type)) if (!start_streaming (pool)) goto start_failed; return TRUE; /* ERRORS */ start_failed: { GST_ERROR_OBJECT (pool, "failed to start streaming"); return FALSE; } }