static GstFlowReturn
gst_v4l2_video_dec_finish (GstVideoDecoder * decoder)
{
GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
GstFlowReturn ret = GST_FLOW_OK;
GstBuffer *buffer;
if (!g_atomic_int_get (&self->processing))
goto done;
GST_DEBUG_OBJECT (self, "Finishing decoding");
GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
if (gst_v4l2_decoder_cmd (self->v4l2output, V4L2_DEC_CMD_STOP, 0)) {
GstTask *task = decoder->srcpad->task;
/* If the decoder stop command succeeded, just wait until processing is
* finished */
GST_OBJECT_LOCK (task);
while (GST_TASK_STATE (task) == GST_TASK_STARTED)
GST_TASK_WAIT (task);
GST_OBJECT_UNLOCK (task);
ret = GST_FLOW_FLUSHING;
} else {
/* otherwise keep queuing empty buffers until the processing thread has
* stopped, _pool_process() will return FLUSHING when that happened */
while (ret == GST_FLOW_OK) {
buffer = gst_buffer_new ();
ret =
gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->
v4l2output->pool), &buffer);
gst_buffer_unref (buffer);
}
}
/* and ensure the processing thread has stopped in case another error
* occured. */
gst_v4l2_object_unlock (self->v4l2capture);
gst_pad_stop_task (decoder->srcpad);
GST_VIDEO_DECODER_STREAM_LOCK (decoder);
if (ret == GST_FLOW_FLUSHING)
ret = self->output_flow;
GST_DEBUG_OBJECT (decoder, "Done draining buffers");
done:
return ret;
}
static GstFlowReturn
gst_v4l2_video_dec_finish (GstVideoDecoder * decoder)
{
GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
GstFlowReturn ret = GST_FLOW_OK;
GstBuffer *buffer;
if (!g_atomic_int_get (&self->processing))
goto done;
GST_DEBUG_OBJECT (self, "Finishing decoding");
/* Keep queuing empty buffers until the processing thread has stopped,
* _pool_process() will return FLUSHING when that happened */
GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
while (ret == GST_FLOW_OK) {
buffer = gst_buffer_new ();
ret =
gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->
v4l2output->pool), &buffer);
gst_buffer_unref (buffer);
}
/* and ensure the processing thread has stopped in case another error
* occured. */
gst_v4l2_object_unlock (self->v4l2capture);
gst_pad_stop_task (decoder->srcpad);
GST_VIDEO_DECODER_STREAM_LOCK (decoder);
if (ret == GST_FLOW_FLUSHING)
ret = self->output_flow;
GST_DEBUG_OBJECT (decoder, "Done draining buffers");
done:
return ret;
}
/* called after A/V sync to render frame */
static GstFlowReturn
gst_v4l2sink_show_frame (GstBaseSink * bsink, GstBuffer * buf)
{
GstFlowReturn ret;
GstV4l2Sink *v4l2sink = GST_V4L2SINK (bsink);
GstV4l2Object *obj = v4l2sink->v4l2object;
GST_DEBUG_OBJECT (v4l2sink, "render buffer: %p", buf);
if (G_UNLIKELY (obj->pool == NULL))
goto not_negotiated;
ret =
gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL_CAST (obj->pool), buf);
return ret;
/* ERRORS */
not_negotiated:
{
GST_ERROR_OBJECT (bsink, "not negotiated");
return GST_FLOW_NOT_NEGOTIATED;
}
}
static GstFlowReturn
gst_v4l2src_create (GstPushSrc * src, GstBuffer ** buf)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (src);
GstV4l2Object *obj = v4l2src->v4l2object;
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL_CAST (obj->pool);
GstFlowReturn ret;
GstClock *clock;
GstClockTime abs_time, base_time, timestamp, duration;
GstClockTime delay;
do {
ret = GST_BASE_SRC_CLASS (parent_class)->alloc (GST_BASE_SRC (src), 0,
obj->info.size, buf);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto alloc_failed;
ret = gst_v4l2_buffer_pool_process (pool, buf);
} while (ret == GST_V4L2_FLOW_CORRUPTED_BUFFER);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto error;
timestamp = GST_BUFFER_TIMESTAMP (*buf);
duration = obj->duration;
/* timestamps, LOCK to get clock and base time. */
/* FIXME: element clock and base_time is rarely changing */
GST_OBJECT_LOCK (v4l2src);
if ((clock = GST_ELEMENT_CLOCK (v4l2src))) {
/* we have a clock, get base time and ref clock */
base_time = GST_ELEMENT (v4l2src)->base_time;
gst_object_ref (clock);
} else {
/* no clock, can't set timestamps */
base_time = GST_CLOCK_TIME_NONE;
}
GST_OBJECT_UNLOCK (v4l2src);
/* sample pipeline clock */
if (clock) {
abs_time = gst_clock_get_time (clock);
gst_object_unref (clock);
} else {
abs_time = GST_CLOCK_TIME_NONE;
}
if (timestamp != GST_CLOCK_TIME_NONE) {
struct timespec now;
GstClockTime gstnow;
/* v4l2 specs say to use the system time although many drivers switched to
* the more desirable monotonic time. We first try to use the monotonic time
* and see how that goes */
clock_gettime (CLOCK_MONOTONIC, &now);
gstnow = GST_TIMESPEC_TO_TIME (now);
if (gstnow < timestamp && (timestamp - gstnow) > (10 * GST_SECOND)) {
GTimeVal now;
/* very large diff, fall back to system time */
g_get_current_time (&now);
gstnow = GST_TIMEVAL_TO_TIME (now);
}
if (gstnow > timestamp) {
delay = gstnow - timestamp;
} else {
delay = 0;
}
GST_DEBUG_OBJECT (v4l2src, "ts: %" GST_TIME_FORMAT " now %" GST_TIME_FORMAT
" delay %" GST_TIME_FORMAT, GST_TIME_ARGS (timestamp),
GST_TIME_ARGS (gstnow), GST_TIME_ARGS (delay));
} else {
/* we assume 1 frame latency otherwise */
if (GST_CLOCK_TIME_IS_VALID (duration))
delay = duration;
else
delay = 0;
}
/* set buffer metadata */
GST_BUFFER_OFFSET (*buf) = v4l2src->offset++;
GST_BUFFER_OFFSET_END (*buf) = v4l2src->offset;
if (G_LIKELY (abs_time != GST_CLOCK_TIME_NONE)) {
/* the time now is the time of the clock minus the base time */
timestamp = abs_time - base_time;
/* adjust for delay in the device */
if (timestamp > delay)
timestamp -= delay;
else
timestamp = 0;
} else {
timestamp = GST_CLOCK_TIME_NONE;
}
/* activate settings for next frame */
if (GST_CLOCK_TIME_IS_VALID (duration)) {
v4l2src->ctrl_time += duration;
} else {
/* this is not very good (as it should be the next timestamp),
* still good enough for linear fades (as long as it is not -1)
*/
v4l2src->ctrl_time = timestamp;
}
gst_object_sync_values (GST_OBJECT (src), v4l2src->ctrl_time);
GST_INFO_OBJECT (src, "sync to %" GST_TIME_FORMAT " out ts %" GST_TIME_FORMAT,
GST_TIME_ARGS (v4l2src->ctrl_time), GST_TIME_ARGS (timestamp));
GST_BUFFER_TIMESTAMP (*buf) = timestamp;
GST_BUFFER_DURATION (*buf) = duration;
return ret;
/* ERROR */
alloc_failed:
{
if (ret != GST_FLOW_FLUSHING)
GST_ELEMENT_ERROR (src, RESOURCE, NO_SPACE_LEFT,
("Failed to allocate a buffer"), (NULL));
return ret;
}
error:
{
if (ret == GST_V4L2_FLOW_LAST_BUFFER) {
GST_ELEMENT_ERROR (src, RESOURCE, FAILED,
("Driver returned a buffer with no payload, this most likely "
"indicate a bug in the driver."), (NULL));
ret = GST_FLOW_ERROR;
} else {
GST_DEBUG_OBJECT (src, "error processing buffer %d (%s)", ret,
gst_flow_get_name (ret));
}
return ret;
}
}
static GstFlowReturn
gst_v4l2src_create (GstPushSrc * src, GstBuffer ** buf)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (src);
GstV4l2Object *obj = v4l2src->v4l2object;
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL_CAST (obj->pool);
GstFlowReturn ret;
GstClock *clock;
GstClockTime abs_time, base_time, timestamp, duration;
GstClockTime delay;
GstMessage *qos_msg;
do {
ret = GST_BASE_SRC_CLASS (parent_class)->alloc (GST_BASE_SRC (src), 0,
obj->info.size, buf);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto alloc_failed;
ret = gst_v4l2_buffer_pool_process (pool, buf);
} while (ret == GST_V4L2_FLOW_CORRUPTED_BUFFER);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto error;
timestamp = GST_BUFFER_TIMESTAMP (*buf);
duration = obj->duration;
/* timestamps, LOCK to get clock and base time. */
/* FIXME: element clock and base_time is rarely changing */
GST_OBJECT_LOCK (v4l2src);
if ((clock = GST_ELEMENT_CLOCK (v4l2src))) {
/* we have a clock, get base time and ref clock */
base_time = GST_ELEMENT (v4l2src)->base_time;
gst_object_ref (clock);
} else {
/* no clock, can't set timestamps */
base_time = GST_CLOCK_TIME_NONE;
}
GST_OBJECT_UNLOCK (v4l2src);
/* sample pipeline clock */
if (clock) {
abs_time = gst_clock_get_time (clock);
gst_object_unref (clock);
} else {
abs_time = GST_CLOCK_TIME_NONE;
}
retry:
if (!v4l2src->has_bad_timestamp && timestamp != GST_CLOCK_TIME_NONE) {
struct timespec now;
GstClockTime gstnow;
/* v4l2 specs say to use the system time although many drivers switched to
* the more desirable monotonic time. We first try to use the monotonic time
* and see how that goes */
clock_gettime (CLOCK_MONOTONIC, &now);
gstnow = GST_TIMESPEC_TO_TIME (now);
if (timestamp > gstnow || (gstnow - timestamp) > (10 * GST_SECOND)) {
GTimeVal now;
/* very large diff, fall back to system time */
g_get_current_time (&now);
gstnow = GST_TIMEVAL_TO_TIME (now);
}
/* Detect buggy drivers here, and stop using their timestamp. Failing any
* of these condition would imply a very buggy driver:
* - Timestamp in the future
* - Timestamp is going backward compare to last seen timestamp
* - Timestamp is jumping forward for less then a frame duration
* - Delay is bigger then the actual timestamp
* */
if (timestamp > gstnow) {
GST_WARNING_OBJECT (v4l2src,
"Timestamp in the future detected, ignoring driver timestamps");
v4l2src->has_bad_timestamp = TRUE;
goto retry;
}
if (v4l2src->last_timestamp > timestamp) {
GST_WARNING_OBJECT (v4l2src,
"Timestamp going backward, ignoring driver timestamps");
v4l2src->has_bad_timestamp = TRUE;
goto retry;
}
delay = gstnow - timestamp;
if (delay > timestamp) {
GST_WARNING_OBJECT (v4l2src,
"Timestamp does not correlate with any clock, ignoring driver timestamps");
v4l2src->has_bad_timestamp = TRUE;
goto retry;
}
/* Save last timestamp for sanity checks */
v4l2src->last_timestamp = timestamp;
GST_DEBUG_OBJECT (v4l2src, "ts: %" GST_TIME_FORMAT " now %" GST_TIME_FORMAT
" delay %" GST_TIME_FORMAT, GST_TIME_ARGS (timestamp),
GST_TIME_ARGS (gstnow), GST_TIME_ARGS (delay));
} else {
/* we assume 1 frame latency otherwise */
if (GST_CLOCK_TIME_IS_VALID (duration))
delay = duration;
else
delay = 0;
}
/* set buffer metadata */
if (G_LIKELY (abs_time != GST_CLOCK_TIME_NONE)) {
/* the time now is the time of the clock minus the base time */
timestamp = abs_time - base_time;
/* adjust for delay in the device */
if (timestamp > delay)
timestamp -= delay;
else
timestamp = 0;
} else {
timestamp = GST_CLOCK_TIME_NONE;
}
/* activate settings for next frame */
if (GST_CLOCK_TIME_IS_VALID (duration)) {
v4l2src->ctrl_time += duration;
} else {
/* this is not very good (as it should be the next timestamp),
* still good enough for linear fades (as long as it is not -1)
*/
v4l2src->ctrl_time = timestamp;
}
gst_object_sync_values (GST_OBJECT (src), v4l2src->ctrl_time);
GST_INFO_OBJECT (src, "sync to %" GST_TIME_FORMAT " out ts %" GST_TIME_FORMAT,
GST_TIME_ARGS (v4l2src->ctrl_time), GST_TIME_ARGS (timestamp));
/* use generated offset values only if there are not already valid ones
* set by the v4l2 device */
if (!GST_BUFFER_OFFSET_IS_VALID (*buf) || !GST_BUFFER_OFFSET_END_IS_VALID (*buf)) {
GST_BUFFER_OFFSET (*buf) = v4l2src->offset++;
GST_BUFFER_OFFSET_END (*buf) = v4l2src->offset;
} else {
/* adjust raw v4l2 device sequence, will restart at null in case of renegotiation
* (streamoff/streamon) */
GST_BUFFER_OFFSET (*buf) += v4l2src->renegotiation_adjust;
GST_BUFFER_OFFSET_END (*buf) += v4l2src->renegotiation_adjust;
/* check for frame loss with given (from v4l2 device) buffer offset */
if ((v4l2src->offset != 0) && (GST_BUFFER_OFFSET (*buf) != (v4l2src->offset + 1))) {
guint64 lost_frame_count = GST_BUFFER_OFFSET (*buf) - v4l2src->offset - 1;
GST_WARNING_OBJECT (v4l2src,
"lost frames detected: count = %" G_GUINT64_FORMAT " - ts: %" GST_TIME_FORMAT,
lost_frame_count, GST_TIME_ARGS (timestamp));
qos_msg = gst_message_new_qos (GST_OBJECT_CAST (v4l2src), TRUE,
GST_CLOCK_TIME_NONE, GST_CLOCK_TIME_NONE, timestamp,
GST_CLOCK_TIME_IS_VALID (duration) ? lost_frame_count * duration : GST_CLOCK_TIME_NONE);
gst_element_post_message (GST_ELEMENT_CAST (v4l2src), qos_msg);
}
v4l2src->offset = GST_BUFFER_OFFSET (*buf);
}
GST_BUFFER_TIMESTAMP (*buf) = timestamp;
GST_BUFFER_DURATION (*buf) = duration;
return ret;
/* ERROR */
alloc_failed:
{
if (ret != GST_FLOW_FLUSHING)
GST_ELEMENT_ERROR (src, RESOURCE, NO_SPACE_LEFT,
("Failed to allocate a buffer"), (NULL));
return ret;
}
error:
{
if (ret == GST_V4L2_FLOW_LAST_BUFFER) {
GST_ELEMENT_ERROR (src, RESOURCE, FAILED,
("Driver returned a buffer with no payload, this most likely "
"indicate a bug in the driver."), (NULL));
ret = GST_FLOW_ERROR;
} else {
GST_DEBUG_OBJECT (src, "error processing buffer %d (%s)", ret,
gst_flow_get_name (ret));
}
return ret;
}
}
static GstFlowReturn
gst_v4l2_transform_prepare_output_buffer (GstBaseTransform * trans,
GstBuffer * inbuf, GstBuffer ** outbuf)
{
GstV4l2Transform *self = GST_V4L2_TRANSFORM (trans);
GstBufferPool *pool = GST_BUFFER_POOL (self->v4l2output->pool);
GstFlowReturn ret = GST_FLOW_OK;
GstBaseTransformClass *bclass = GST_BASE_TRANSFORM_CLASS (parent_class);
if (gst_base_transform_is_passthrough (trans)) {
GST_DEBUG_OBJECT (self, "Passthrough, no need to do anything");
*outbuf = inbuf;
goto beach;
}
/* Ensure input internal pool is active */
if (!gst_buffer_pool_is_active (pool)) {
GstStructure *config = gst_buffer_pool_get_config (pool);
gst_buffer_pool_config_set_params (config, self->incaps,
self->v4l2output->info.size, 2, 2);
/* There is no reason to refuse this config */
if (!gst_buffer_pool_set_config (pool, config))
goto activate_failed;
if (!gst_buffer_pool_set_active (pool, TRUE))
goto activate_failed;
}
GST_DEBUG_OBJECT (self, "Queue input buffer");
ret = gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (pool), &inbuf);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto beach;
do {
pool = gst_base_transform_get_buffer_pool (trans);
if (!gst_buffer_pool_set_active (pool, TRUE))
goto activate_failed;
GST_DEBUG_OBJECT (self, "Dequeue output buffer");
ret = gst_buffer_pool_acquire_buffer (pool, outbuf, NULL);
g_object_unref (pool);
if (ret != GST_FLOW_OK)
goto alloc_failed;
pool = self->v4l2capture->pool;
ret = gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (pool), outbuf);
} while (ret == GST_V4L2_FLOW_CORRUPTED_BUFFER);
if (ret != GST_FLOW_OK) {
gst_buffer_unref (*outbuf);
*outbuf = NULL;
}
if (bclass->copy_metadata)
if (!bclass->copy_metadata (trans, inbuf, *outbuf)) {
/* something failed, post a warning */
GST_ELEMENT_WARNING (self, STREAM, NOT_IMPLEMENTED,
("could not copy metadata"), (NULL));
}
beach:
return ret;
activate_failed:
GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS,
("failed to activate bufferpool"), ("failed to activate bufferpool"));
g_object_unref (pool);
return GST_FLOW_ERROR;
alloc_failed:
GST_DEBUG_OBJECT (self, "could not allocate buffer from pool");
return ret;
}
static GstFlowReturn
gst_v4l2_video_dec_handle_frame (GstVideoDecoder * decoder,
GstVideoCodecFrame * frame)
{
GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
GstFlowReturn ret = GST_FLOW_OK;
GST_DEBUG_OBJECT (self, "Handling frame %d", frame->system_frame_number);
if (G_UNLIKELY (!g_atomic_int_get (&self->active)))
goto flushing;
if (G_UNLIKELY (!GST_V4L2_IS_ACTIVE (self->v4l2output))) {
if (!self->input_state)
goto not_negotiated;
if (!gst_v4l2_object_set_format (self->v4l2output, self->input_state->caps))
goto not_negotiated;
}
if (G_UNLIKELY (!GST_V4L2_IS_ACTIVE (self->v4l2capture))) {
GstBufferPool *pool = GST_BUFFER_POOL (self->v4l2output->pool);
GstVideoInfo info;
GstVideoCodecState *output_state;
GstBuffer *codec_data;
GST_DEBUG_OBJECT (self, "Sending header");
codec_data = self->input_state->codec_data;
/* We are running in byte-stream mode, so we don't know the headers, but
* we need to send something, otherwise the decoder will refuse to
* intialize.
*/
if (codec_data) {
gst_buffer_ref (codec_data);
} else {
codec_data = frame->input_buffer;
frame->input_buffer = NULL;
}
/* Ensure input internal pool is active */
if (!gst_buffer_pool_is_active (pool)) {
GstStructure *config = gst_buffer_pool_get_config (pool);
gst_buffer_pool_config_set_params (config, self->input_state->caps,
self->v4l2output->info.size, 2, 2);
/* There is no reason to refuse this config */
if (!gst_buffer_pool_set_config (pool, config))
goto activate_failed;
if (!gst_buffer_pool_set_active (pool, TRUE))
goto activate_failed;
}
GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
ret =
gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->
v4l2output->pool), &codec_data);
GST_VIDEO_DECODER_STREAM_LOCK (decoder);
gst_buffer_unref (codec_data);
if (!gst_v4l2_object_acquire_format (self->v4l2capture, &info))
goto not_negotiated;
output_state = gst_video_decoder_set_output_state (decoder,
info.finfo->format, info.width, info.height, self->input_state);
/* Copy the rest of the information, there might be more in the future */
output_state->info.interlace_mode = info.interlace_mode;
gst_video_codec_state_unref (output_state);
if (!gst_video_decoder_negotiate (decoder)) {
if (GST_PAD_IS_FLUSHING (decoder->srcpad))
goto flushing;
else
goto not_negotiated;
}
/* Ensure our internal pool is activated */
if (!gst_buffer_pool_set_active (GST_BUFFER_POOL (self->v4l2capture->pool),
TRUE))
goto activate_failed;
}
if (g_atomic_int_get (&self->processing) == FALSE) {
/* It's possible that the processing thread stopped due to an error */
if (self->output_flow != GST_FLOW_OK &&
self->output_flow != GST_FLOW_FLUSHING) {
GST_DEBUG_OBJECT (self, "Processing loop stopped with error, leaving");
ret = self->output_flow;
goto drop;
}
GST_DEBUG_OBJECT (self, "Starting decoding thread");
/* Start the processing task, when it quits, the task will disable input
* processing to unlock input if draining, or prevent potential block */
g_atomic_int_set (&self->processing, TRUE);
if (!gst_pad_start_task (decoder->srcpad,
(GstTaskFunction) gst_v4l2_video_dec_loop, self,
(GDestroyNotify) gst_v4l2_video_dec_loop_stopped))
goto start_task_failed;
}
if (frame->input_buffer) {
GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
ret =
gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->v4l2output->
pool), &frame->input_buffer);
GST_VIDEO_DECODER_STREAM_LOCK (decoder);
if (ret == GST_FLOW_FLUSHING) {
if (g_atomic_int_get (&self->processing) == FALSE)
ret = self->output_flow;
goto drop;
} else if (ret != GST_FLOW_OK) {
goto process_failed;
}
/* No need to keep input arround */
gst_buffer_replace (&frame->input_buffer, NULL);
}
gst_video_codec_frame_unref (frame);
return ret;
/* ERRORS */
not_negotiated:
{
GST_ERROR_OBJECT (self, "not negotiated");
ret = GST_FLOW_NOT_NEGOTIATED;
goto drop;
}
activate_failed:
{
GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS,
(_("Failed to allocate required memory.")),
("Buffer pool activation failed"));
ret = GST_FLOW_ERROR;
goto drop;
}
flushing:
{
ret = GST_FLOW_FLUSHING;
goto drop;
}
start_task_failed:
{
GST_ELEMENT_ERROR (self, RESOURCE, FAILED,
(_("Failed to start decoding thread.")), (NULL));
g_atomic_int_set (&self->processing, FALSE);
ret = GST_FLOW_ERROR;
goto drop;
}
process_failed:
{
GST_ELEMENT_ERROR (self, RESOURCE, FAILED,
(_("Failed to process frame.")),
("Maybe be due to not enough memory or failing driver"));
ret = GST_FLOW_ERROR;
goto drop;
}
drop:
{
gst_video_decoder_drop_frame (decoder, frame);
return ret;
}
}
static void
gst_v4l2_video_dec_loop (GstVideoDecoder * decoder)
{
GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
GstV4l2BufferPool *v4l2_pool = GST_V4L2_BUFFER_POOL (self->v4l2capture->pool);
GstBufferPool *pool;
GstVideoCodecFrame *frame;
GstBuffer *buffer = NULL;
GstFlowReturn ret;
GST_LOG_OBJECT (decoder, "Allocate output buffer");
do {
/* We cannot use the base class allotate helper since it taking the internal
* stream lock. we know that the acquire may need to poll until more frames
* comes in and holding this lock would prevent that.
*/
pool = gst_video_decoder_get_buffer_pool (decoder);
/* Pool may be NULL if we started going to READY state */
if (pool == NULL) {
ret = GST_FLOW_FLUSHING;
goto beach;
}
ret = gst_buffer_pool_acquire_buffer (pool, &buffer, NULL);
g_object_unref (pool);
if (ret != GST_FLOW_OK)
goto beach;
GST_LOG_OBJECT (decoder, "Process output buffer");
ret = gst_v4l2_buffer_pool_process (v4l2_pool, &buffer);
} while (ret == GST_V4L2_FLOW_CORRUPTED_BUFFER);
if (ret != GST_FLOW_OK)
goto beach;
frame = gst_v4l2_video_dec_get_oldest_frame (decoder);
if (frame) {
frame->output_buffer = buffer;
buffer = NULL;
ret = gst_video_decoder_finish_frame (decoder, frame);
if (ret != GST_FLOW_OK)
goto beach;
} else {
GST_WARNING_OBJECT (decoder, "Decoder is producing too many buffers");
gst_buffer_unref (buffer);
}
return;
beach:
GST_DEBUG_OBJECT (decoder, "Leaving output thread: %s",
gst_flow_get_name (ret));
gst_buffer_replace (&buffer, NULL);
self->output_flow = ret;
g_atomic_int_set (&self->processing, FALSE);
gst_v4l2_object_unlock (self->v4l2output);
gst_pad_pause_task (decoder->srcpad);
}
static GstFlowReturn
gst_v4l2_video_dec_handle_frame (GstVideoDecoder * decoder,
GstVideoCodecFrame * frame)
{
GstV4l2Error error = GST_V4L2_ERROR_INIT;
GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
GstFlowReturn ret = GST_FLOW_OK;
gboolean processed = FALSE;
GstBuffer *tmp;
GST_DEBUG_OBJECT (self, "Handling frame %d", frame->system_frame_number);
if (G_UNLIKELY (!g_atomic_int_get (&self->active)))
goto flushing;
if (G_UNLIKELY (!GST_V4L2_IS_ACTIVE (self->v4l2output))) {
if (!self->input_state)
goto not_negotiated;
if (!gst_v4l2_object_set_format (self->v4l2output, self->input_state->caps,
&error))
goto not_negotiated;
}
if (G_UNLIKELY (!GST_V4L2_IS_ACTIVE (self->v4l2capture))) {
GstBufferPool *pool = GST_BUFFER_POOL (self->v4l2output->pool);
GstVideoInfo info;
GstVideoCodecState *output_state;
GstBuffer *codec_data;
GstCaps *acquired_caps, *available_caps, *caps, *filter;
GstStructure *st;
GST_DEBUG_OBJECT (self, "Sending header");
codec_data = self->input_state->codec_data;
/* We are running in byte-stream mode, so we don't know the headers, but
* we need to send something, otherwise the decoder will refuse to
* intialize.
*/
if (codec_data) {
gst_buffer_ref (codec_data);
} else {
codec_data = gst_buffer_ref (frame->input_buffer);
processed = TRUE;
}
/* Ensure input internal pool is active */
if (!gst_buffer_pool_is_active (pool)) {
GstStructure *config = gst_buffer_pool_get_config (pool);
gst_buffer_pool_config_set_params (config, self->input_state->caps,
self->v4l2output->info.size, 2, 2);
/* There is no reason to refuse this config */
if (!gst_buffer_pool_set_config (pool, config))
goto activate_failed;
if (!gst_buffer_pool_set_active (pool, TRUE))
goto activate_failed;
}
GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
ret =
gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->
v4l2output->pool), &codec_data);
GST_VIDEO_DECODER_STREAM_LOCK (decoder);
gst_buffer_unref (codec_data);
/* For decoders G_FMT returns coded size, G_SELECTION returns visible size
* in the compose rectangle. gst_v4l2_object_acquire_format() checks both
* and returns the visible size as with/height and the coded size as
* padding. */
if (!gst_v4l2_object_acquire_format (self->v4l2capture, &info))
goto not_negotiated;
/* Create caps from the acquired format, remove the format field */
acquired_caps = gst_video_info_to_caps (&info);
st = gst_caps_get_structure (acquired_caps, 0);
gst_structure_remove_field (st, "format");
/* Probe currently available pixel formats */
available_caps = gst_v4l2_object_probe_caps (self->v4l2capture, NULL);
available_caps = gst_caps_make_writable (available_caps);
/* Replace coded size with visible size, we want to negotiate visible size
* with downstream, not coded size. */
gst_caps_map_in_place (available_caps, gst_v4l2_video_remove_padding, self);
filter = gst_caps_intersect_full (available_caps, acquired_caps,
GST_CAPS_INTERSECT_FIRST);
gst_caps_unref (acquired_caps);
gst_caps_unref (available_caps);
caps = gst_pad_peer_query_caps (decoder->srcpad, filter);
gst_caps_unref (filter);
GST_DEBUG_OBJECT (self, "Possible decoded caps: %" GST_PTR_FORMAT, caps);
if (gst_caps_is_empty (caps)) {
gst_caps_unref (caps);
goto not_negotiated;
}
/* Fixate pixel format */
caps = gst_caps_fixate (caps);
GST_DEBUG_OBJECT (self, "Chosen decoded caps: %" GST_PTR_FORMAT, caps);
/* Try to set negotiated format, on success replace acquired format */
if (gst_v4l2_object_set_format (self->v4l2capture, caps, &error))
gst_video_info_from_caps (&info, caps);
else
gst_v4l2_clear_error (&error);
gst_caps_unref (caps);
output_state = gst_video_decoder_set_output_state (decoder,
info.finfo->format, info.width, info.height, self->input_state);
/* Copy the rest of the information, there might be more in the future */
output_state->info.interlace_mode = info.interlace_mode;
gst_video_codec_state_unref (output_state);
if (!gst_video_decoder_negotiate (decoder)) {
if (GST_PAD_IS_FLUSHING (decoder->srcpad))
goto flushing;
else
goto not_negotiated;
}
/* Ensure our internal pool is activated */
if (!gst_buffer_pool_set_active (GST_BUFFER_POOL (self->v4l2capture->pool),
TRUE))
goto activate_failed;
}
if (g_atomic_int_get (&self->processing) == FALSE) {
/* It's possible that the processing thread stopped due to an error */
if (self->output_flow != GST_FLOW_OK &&
self->output_flow != GST_FLOW_FLUSHING) {
GST_DEBUG_OBJECT (self, "Processing loop stopped with error, leaving");
ret = self->output_flow;
goto drop;
}
GST_DEBUG_OBJECT (self, "Starting decoding thread");
/* Start the processing task, when it quits, the task will disable input
* processing to unlock input if draining, or prevent potential block */
g_atomic_int_set (&self->processing, TRUE);
if (!gst_pad_start_task (decoder->srcpad,
(GstTaskFunction) gst_v4l2_video_dec_loop, self,
(GDestroyNotify) gst_v4l2_video_dec_loop_stopped))
goto start_task_failed;
}
if (!processed) {
GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
ret =
gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->v4l2output->
pool), &frame->input_buffer);
GST_VIDEO_DECODER_STREAM_LOCK (decoder);
if (ret == GST_FLOW_FLUSHING) {
if (g_atomic_int_get (&self->processing) == FALSE)
ret = self->output_flow;
goto drop;
} else if (ret != GST_FLOW_OK) {
goto process_failed;
}
}
/* No need to keep input arround */
tmp = frame->input_buffer;
frame->input_buffer = gst_buffer_new ();
gst_buffer_copy_into (frame->input_buffer, tmp,
GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS |
GST_BUFFER_COPY_META, 0, 0);
gst_buffer_unref (tmp);
gst_video_codec_frame_unref (frame);
return ret;
/* ERRORS */
not_negotiated:
{
GST_ERROR_OBJECT (self, "not negotiated");
ret = GST_FLOW_NOT_NEGOTIATED;
gst_v4l2_error (self, &error);
goto drop;
}
activate_failed:
{
GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS,
(_("Failed to allocate required memory.")),
("Buffer pool activation failed"));
ret = GST_FLOW_ERROR;
goto drop;
}
flushing:
{
ret = GST_FLOW_FLUSHING;
goto drop;
}
start_task_failed:
{
GST_ELEMENT_ERROR (self, RESOURCE, FAILED,
(_("Failed to start decoding thread.")), (NULL));
g_atomic_int_set (&self->processing, FALSE);
ret = GST_FLOW_ERROR;
goto drop;
}
process_failed:
{
GST_ELEMENT_ERROR (self, RESOURCE, FAILED,
(_("Failed to process frame.")),
("Maybe be due to not enough memory or failing driver"));
ret = GST_FLOW_ERROR;
goto drop;
}
drop:
{
gst_video_decoder_drop_frame (decoder, frame);
return ret;
}
}