void unmapGstBuffer(GstBuffer* buffer)
{
GstMiniObject* miniObject = reinterpret_cast<GstMiniObject*>(buffer);
GstMapInfo* mapInfo = static_cast<GstMapInfo*>(gst_mini_object_steal_qdata(miniObject, g_quark_from_static_string(webkitGstMapInfoQuarkString)));
if (!mapInfo)
return;
gst_buffer_unmap(buffer, mapInfo);
g_slice_free(GstMapInfo, mapInfo);
}
/**
* 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)) {
/* don't check return value because qbuf would have failed */
gst_v4l2_is_buffer_valid (to_queue, &group);
/* qbuf has taken the ref of the to_queue buffer but we are no in
* streaming state, so the flush logic won't be performed.
* To avoid leaks, flush the allocator and restore the queued
* buffer as non-queued */
gst_v4l2_allocator_flush (pool->vallocator);
pool->buffers[group->buffer.index] = NULL;
gst_mini_object_set_qdata (GST_MINI_OBJECT (to_queue),
GST_V4L2_IMPORT_QUARK, NULL, NULL);
gst_buffer_unref (to_queue);
g_atomic_int_add (&pool->num_queued, -1);
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;
}
}