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|
/* GStreamer
* Copyright (C) 2010, 2013 Ole André Vadla Ravnås <oleavr@soundrop.com>
* Copyright (C) 2012, 2013 Alessandro Decina <alessandro.d@gmail.com>
*
* 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 Street, Suite 500,
* Boston, MA 02110-1335, USA.
*/
/**
* SECTION:element-gstvtdec
*
* Apple VideoToolbox based decoder.
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch -v filesrc location=file.mov ! qtdemux ! queue ! h264parse ! vtdec ! videoconvert ! autovideosink
* ]|
* Decode h264 video from a mov file.
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include <gst/video/video.h>
#include <gst/video/gstvideodecoder.h>
#include "vtdec.h"
#include "vtutil.h"
#include "corevideobuffer.h"
#include <string.h>
GST_DEBUG_CATEGORY_STATIC (gst_vtdec_debug_category);
#define GST_CAT_DEFAULT gst_vtdec_debug_category
static void gst_vtdec_finalize (GObject * object);
static gboolean gst_vtdec_start (GstVideoDecoder * decoder);
static gboolean gst_vtdec_stop (GstVideoDecoder * decoder);
static gboolean gst_vtdec_set_format (GstVideoDecoder * decoder,
GstVideoCodecState * state);
static gboolean gst_vtdec_flush (GstVideoDecoder * decoder);
static GstFlowReturn gst_vtdec_finish (GstVideoDecoder * decoder);
static GstFlowReturn gst_vtdec_handle_frame (GstVideoDecoder * decoder,
GstVideoCodecFrame * frame);
static gboolean gst_vtdec_create_session (GstVtdec * vtdec);
static void gst_vtdec_invalidate_session (GstVtdec * vtdec);
static CMSampleBufferRef cm_sample_buffer_from_gst_buffer (GstVtdec * vtdec,
GstBuffer * buf);
static GstFlowReturn gst_vtdec_push_frames_if_needed (GstVtdec * vtdec,
gboolean drain, gboolean flush);
static CMFormatDescriptionRef create_format_description (GstVtdec * vtdec,
CMVideoCodecType cm_format);
static CMFormatDescriptionRef
create_format_description_from_codec_data (GstVtdec * vtdec,
CMVideoCodecType cm_format, GstBuffer * codec_data);
static void gst_vtdec_session_output_callback (void
*decompression_output_ref_con, void *source_frame_ref_con, OSStatus status,
VTDecodeInfoFlags info_flags, CVImageBufferRef image_buffer, CMTime pts,
CMTime duration);
static gboolean compute_h264_decode_picture_buffer_length (GstVtdec * vtdec,
GstBuffer * codec_data, int *length);
static gboolean gst_vtdec_compute_reorder_queue_length (GstVtdec * vtdec,
CMVideoCodecType cm_format, GstBuffer * codec_data);
static void gst_vtdec_set_latency (GstVtdec * vtdec);
static GstStaticPadTemplate gst_vtdec_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("video/x-h264, stream-format=avc, alignment=au;"
"video/mpeg, mpegversion=2;" "image/jpeg")
);
#ifdef HAVE_IOS
#define GST_VTDEC_VIDEO_FORMAT_STR "NV12"
#define GST_VTDEC_VIDEO_FORMAT GST_VIDEO_FORMAT_NV12
#define GST_VTDEC_CV_VIDEO_FORMAT kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange
#else
#define GST_VTDEC_VIDEO_FORMAT_STR "UYVY"
#define GST_VTDEC_VIDEO_FORMAT GST_VIDEO_FORMAT_UYVY
#define GST_VTDEC_CV_VIDEO_FORMAT kCVPixelFormatType_422YpCbCr8
#endif
#define VIDEO_SRC_CAPS \
GST_VIDEO_CAPS_MAKE("{" GST_VTDEC_VIDEO_FORMAT_STR "}")
G_DEFINE_TYPE_WITH_CODE (GstVtdec, gst_vtdec, GST_TYPE_VIDEO_DECODER,
GST_DEBUG_CATEGORY_INIT (gst_vtdec_debug_category, "vtdec", 0,
"debug category for vtdec element"));
static void
gst_vtdec_class_init (GstVtdecClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstVideoDecoderClass *video_decoder_class = GST_VIDEO_DECODER_CLASS (klass);
/* Setting up pads and setting metadata should be moved to
base_class_init if you intend to subclass this class. */
gst_element_class_add_pad_template (GST_ELEMENT_CLASS (klass),
gst_static_pad_template_get (&gst_vtdec_sink_template));
gst_element_class_add_pad_template (GST_ELEMENT_CLASS (klass),
gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
gst_caps_from_string (VIDEO_SRC_CAPS)));
gst_element_class_set_static_metadata (GST_ELEMENT_CLASS (klass),
"Apple VideoToolbox decoder",
"Codec/Decoder/Video",
"Apple VideoToolbox Decoder",
"Ole André Vadla Ravnås <oleavr@soundrop.com>; "
"Alessandro Decina <alessandro.d@gmail.com>");
gobject_class->finalize = gst_vtdec_finalize;
video_decoder_class->start = GST_DEBUG_FUNCPTR (gst_vtdec_start);
video_decoder_class->stop = GST_DEBUG_FUNCPTR (gst_vtdec_stop);
video_decoder_class->set_format = GST_DEBUG_FUNCPTR (gst_vtdec_set_format);
video_decoder_class->flush = GST_DEBUG_FUNCPTR (gst_vtdec_flush);
video_decoder_class->finish = GST_DEBUG_FUNCPTR (gst_vtdec_finish);
video_decoder_class->handle_frame =
GST_DEBUG_FUNCPTR (gst_vtdec_handle_frame);
}
static void
gst_vtdec_init (GstVtdec * vtdec)
{
vtdec->reorder_queue = g_async_queue_new ();
}
void
gst_vtdec_finalize (GObject * object)
{
GstVtdec *vtdec = GST_VTDEC (object);
GST_DEBUG_OBJECT (vtdec, "finalize");
g_async_queue_unref (vtdec->reorder_queue);
G_OBJECT_CLASS (gst_vtdec_parent_class)->finalize (object);
}
static gboolean
gst_vtdec_start (GstVideoDecoder * decoder)
{
GstVtdec *vtdec = GST_VTDEC (decoder);
GST_DEBUG_OBJECT (vtdec, "start");
return TRUE;
}
static gboolean
gst_vtdec_stop (GstVideoDecoder * decoder)
{
GstVtdec *vtdec = GST_VTDEC (decoder);
if (vtdec->session)
gst_vtdec_invalidate_session (vtdec);
GST_DEBUG_OBJECT (vtdec, "stop");
return TRUE;
}
static gboolean
gst_vtdec_set_format (GstVideoDecoder * decoder, GstVideoCodecState * state)
{
GstStructure *structure;
CMVideoCodecType cm_format = 0;
CMFormatDescriptionRef format_description = NULL;
const char *caps_name;
GstVtdec *vtdec = GST_VTDEC (decoder);
GST_DEBUG_OBJECT (vtdec, "set_format");
structure = gst_caps_get_structure (state->caps, 0);
caps_name = gst_structure_get_name (structure);
if (!strcmp (caps_name, "video/x-h264")) {
cm_format = kCMVideoCodecType_H264;
} else if (!strcmp (caps_name, "video/mpeg")) {
cm_format = kCMVideoCodecType_MPEG2Video;
} else if (!strcmp (caps_name, "image/jpeg")) {
cm_format = kCMVideoCodecType_JPEG;
}
if (cm_format == kCMVideoCodecType_H264 && state->codec_data == NULL) {
GST_INFO_OBJECT (vtdec, "no codec data, wait for one");
return TRUE;
}
if (vtdec->session)
gst_vtdec_invalidate_session (vtdec);
gst_video_info_from_caps (&vtdec->video_info, state->caps);
if (!gst_vtdec_compute_reorder_queue_length (vtdec, cm_format,
state->codec_data))
return FALSE;
gst_vtdec_set_latency (vtdec);
if (state->codec_data) {
format_description = create_format_description_from_codec_data (vtdec,
cm_format, state->codec_data);
} else {
format_description = create_format_description (vtdec, cm_format);
}
if (vtdec->format_description)
CFRelease (vtdec->format_description);
vtdec->format_description = format_description;
if (!gst_vtdec_create_session (vtdec))
return FALSE;
gst_video_decoder_set_output_state (decoder,
GST_VTDEC_VIDEO_FORMAT, vtdec->video_info.width, vtdec->video_info.height,
state);
return TRUE;
}
static gboolean
gst_vtdec_flush (GstVideoDecoder * decoder)
{
GstVtdec *vtdec = GST_VTDEC (decoder);
GST_DEBUG_OBJECT (vtdec, "flush");
gst_vtdec_push_frames_if_needed (vtdec, FALSE, TRUE);
return TRUE;
}
static GstFlowReturn
gst_vtdec_finish (GstVideoDecoder * decoder)
{
GstVtdec *vtdec = GST_VTDEC (decoder);
GST_DEBUG_OBJECT (vtdec, "finish");
return gst_vtdec_push_frames_if_needed (vtdec, TRUE, FALSE);
}
static GstFlowReturn
gst_vtdec_handle_frame (GstVideoDecoder * decoder, GstVideoCodecFrame * frame)
{
OSStatus status;
CMSampleBufferRef cm_sample_buffer = NULL;
VTDecodeFrameFlags input_flags, output_flags;
GstVtdec *vtdec = GST_VTDEC (decoder);
GstFlowReturn ret = GST_FLOW_OK;
int decode_frame_number = frame->decode_frame_number;
if (vtdec->format_description == NULL) {
ret = GST_FLOW_NOT_NEGOTIATED;
goto out;
}
GST_LOG_OBJECT (vtdec, "got input frame %d", decode_frame_number);
ret = gst_vtdec_push_frames_if_needed (vtdec, FALSE, FALSE);
if (ret != GST_FLOW_OK)
return ret;
/* don't bother enabling kVTDecodeFrame_EnableTemporalProcessing at all since
* it's not mandatory for the underlying VT codec to respect it. KISS and do
* reordering ourselves.
*/
input_flags = kVTDecodeFrame_EnableAsynchronousDecompression;
output_flags = 0;
cm_sample_buffer =
cm_sample_buffer_from_gst_buffer (vtdec, frame->input_buffer);
status =
VTDecompressionSessionDecodeFrame (vtdec->session, cm_sample_buffer,
input_flags, frame, NULL);
if (status != noErr && FALSE)
goto error;
GST_LOG_OBJECT (vtdec, "submitted input frame %d", decode_frame_number);
out:
if (cm_sample_buffer)
CFRelease (cm_sample_buffer);
return ret;
error:
GST_ELEMENT_ERROR (vtdec, STREAM, DECODE, (NULL),
("VTDecompressionSessionDecodeFrame returned %d", status));
ret = GST_FLOW_ERROR;
goto out;
}
static gboolean
gst_vtdec_create_session (GstVtdec * vtdec)
{
CFMutableDictionaryRef output_image_buffer_attrs;
VTDecompressionOutputCallbackRecord callback;
OSStatus status;
output_image_buffer_attrs =
CFDictionaryCreateMutable (NULL, 0, &kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks);
gst_vtutil_dict_set_i32 (output_image_buffer_attrs,
kCVPixelBufferPixelFormatTypeKey, GST_VTDEC_CV_VIDEO_FORMAT);
gst_vtutil_dict_set_i32 (output_image_buffer_attrs, kCVPixelBufferWidthKey,
vtdec->video_info.width);
gst_vtutil_dict_set_i32 (output_image_buffer_attrs, kCVPixelBufferHeightKey,
vtdec->video_info.height);
gst_vtutil_dict_set_i32 (output_image_buffer_attrs,
kCVPixelBufferBytesPerRowAlignmentKey, 2 * vtdec->video_info.width);
callback.decompressionOutputCallback = gst_vtdec_session_output_callback;
callback.decompressionOutputRefCon = vtdec;
status = VTDecompressionSessionCreate (NULL, vtdec->format_description,
NULL, output_image_buffer_attrs, &callback, &vtdec->session);
CFRelease (output_image_buffer_attrs);
if (status != noErr) {
GST_ELEMENT_ERROR (vtdec, RESOURCE, FAILED, (NULL),
("VTDecompressionSessionCreate returned %d", status));
return FALSE;
}
return TRUE;
}
static void
gst_vtdec_invalidate_session (GstVtdec * vtdec)
{
g_return_if_fail (vtdec->session);
VTDecompressionSessionInvalidate (vtdec->session);
CFRelease (vtdec->session);
vtdec->session = NULL;
}
static CMFormatDescriptionRef
create_format_description (GstVtdec * vtdec, CMVideoCodecType cm_format)
{
OSStatus status;
CMFormatDescriptionRef format_description;
status = CMVideoFormatDescriptionCreate (NULL,
cm_format, vtdec->video_info.width, vtdec->video_info.height,
NULL, &format_description);
if (status != noErr)
return NULL;
return format_description;
}
static CMFormatDescriptionRef
create_format_description_from_codec_data (GstVtdec * vtdec,
CMVideoCodecType cm_format, GstBuffer * codec_data)
{
CMFormatDescriptionRef fmt_desc;
CFMutableDictionaryRef extensions, par, atoms;
GstMapInfo map;
OSStatus status;
/* Extensions dict */
extensions =
CFDictionaryCreateMutable (NULL, 0, &kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks);
gst_vtutil_dict_set_string (extensions,
CFSTR ("CVImageBufferChromaLocationBottomField"), "left");
gst_vtutil_dict_set_string (extensions,
CFSTR ("CVImageBufferChromaLocationTopField"), "left");
gst_vtutil_dict_set_boolean (extensions, CFSTR ("FullRangeVideo"), FALSE);
/* CVPixelAspectRatio dict */
par = CFDictionaryCreateMutable (NULL, 0, &kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks);
gst_vtutil_dict_set_i32 (par, CFSTR ("HorizontalSpacing"),
vtdec->video_info.par_n);
gst_vtutil_dict_set_i32 (par, CFSTR ("VerticalSpacing"),
vtdec->video_info.par_d);
gst_vtutil_dict_set_object (extensions, CFSTR ("CVPixelAspectRatio"),
(CFTypeRef *) par);
/* SampleDescriptionExtensionAtoms dict */
gst_buffer_map (codec_data, &map, GST_MAP_READ);
atoms = CFDictionaryCreateMutable (NULL, 0, &kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks);
gst_vtutil_dict_set_data (atoms, CFSTR ("avcC"), map.data, map.size);
gst_vtutil_dict_set_object (extensions,
CFSTR ("SampleDescriptionExtensionAtoms"), (CFTypeRef *) atoms);
gst_buffer_unmap (codec_data, &map);
status = CMVideoFormatDescriptionCreate (NULL,
cm_format, vtdec->video_info.width, vtdec->video_info.height,
extensions, &fmt_desc);
if (status == noErr)
return fmt_desc;
else
return NULL;
}
static CMSampleBufferRef
cm_sample_buffer_from_gst_buffer (GstVtdec * vtdec, GstBuffer * buf)
{
OSStatus status;
CMBlockBufferRef bbuf = NULL;
CMSampleBufferRef sbuf = NULL;
GstMapInfo map;
CMSampleTimingInfo sample_timing;
CMSampleTimingInfo time_array[1];
g_return_val_if_fail (vtdec->format_description, NULL);
gst_buffer_map (buf, &map, GST_MAP_READ);
/* create a block buffer, the CoreMedia equivalent of GstMemory */
status = CMBlockBufferCreateWithMemoryBlock (NULL,
map.data, (gint64) map.size, kCFAllocatorNull, NULL, 0, (gint64) map.size,
FALSE, &bbuf);
gst_buffer_unmap (buf, &map);
if (status != noErr)
goto block_error;
/* create a sample buffer, the CoreMedia equivalent of GstBuffer */
sample_timing.duration = CMTimeMake (GST_BUFFER_DURATION (buf), 1);
sample_timing.presentationTimeStamp = CMTimeMake (GST_BUFFER_PTS (buf), 1);
sample_timing.decodeTimeStamp = CMTimeMake (GST_BUFFER_DTS (buf), 1);
time_array[0] = sample_timing;
status =
CMSampleBufferCreate (NULL, bbuf, TRUE, 0, 0, vtdec->format_description,
1, 1, time_array, 0, NULL, &sbuf);
if (status != noErr)
goto sample_error;
out:
return sbuf;
block_error:
GST_ELEMENT_ERROR (vtdec, RESOURCE, FAILED, (NULL),
("CMBlockBufferCreateWithMemoryBlock returned %d", status));
goto out;
sample_error:
GST_ELEMENT_ERROR (vtdec, RESOURCE, FAILED, (NULL),
("CMSampleBufferCreate returned %d", status));
if (bbuf)
CFRelease (bbuf);
goto out;
}
static gint
sort_frames_by_pts (gconstpointer f1, gconstpointer f2, gpointer user_data)
{
GstVideoCodecFrame *frame1, *frame2;
GstClockTime pts1, pts2;
frame1 = (GstVideoCodecFrame *) f1;
frame2 = (GstVideoCodecFrame *) f2;
pts1 = GST_BUFFER_PTS (frame1->output_buffer);
pts2 = GST_BUFFER_PTS (frame2->output_buffer);
if (!GST_CLOCK_TIME_IS_VALID (pts1) || !GST_CLOCK_TIME_IS_VALID (pts2))
return 0;
if (pts1 < pts2)
return -1;
else if (pts1 == pts2)
return 0;
else
return 1;
}
static void
gst_vtdec_session_output_callback (void *decompression_output_ref_con,
void *source_frame_ref_con, OSStatus status, VTDecodeInfoFlags info_flags,
CVImageBufferRef image_buffer, CMTime pts, CMTime duration)
{
GstVtdec *vtdec = (GstVtdec *) decompression_output_ref_con;
GstVideoCodecFrame *frame = (GstVideoCodecFrame *) source_frame_ref_con;
GstBuffer *buf;
GstVideoCodecState *state;
GST_LOG_OBJECT (vtdec, "got output frame %p %d", frame,
frame->decode_frame_number);
if (status != noErr) {
GST_ERROR_OBJECT (vtdec, "Error decoding frame %d", status);
goto drop;
}
if (info_flags & kVTDecodeInfo_FrameDropped)
goto drop;
/* FIXME: use gst_video_decoder_allocate_output_buffer */
state = gst_video_decoder_get_output_state (GST_VIDEO_DECODER (vtdec));
buf = gst_core_video_buffer_new (image_buffer, &state->info);
gst_video_codec_state_unref (state);
frame->output_buffer = buf;
gst_buffer_copy_into (buf, frame->input_buffer,
GST_BUFFER_COPY_METADATA | GST_BUFFER_COPY_FLAGS, 0, -1);
GST_BUFFER_PTS (buf) = pts.value;
GST_BUFFER_DURATION (buf) = duration.value;
g_async_queue_push_sorted (vtdec->reorder_queue, frame,
sort_frames_by_pts, NULL);
return;
drop:
GST_WARNING_OBJECT (vtdec, "Frame dropped %p %d", frame,
frame->decode_frame_number);
gst_video_decoder_drop_frame (GST_VIDEO_DECODER (vtdec), frame);
}
static GstFlowReturn
gst_vtdec_push_frames_if_needed (GstVtdec * vtdec, gboolean drain,
gboolean flush)
{
GstVideoCodecFrame *frame;
GstFlowReturn ret = GST_FLOW_OK;
GstVideoDecoder *decoder = GST_VIDEO_DECODER (vtdec);
if (drain)
VTDecompressionSessionWaitForAsynchronousFrames (vtdec->session);
/* push a buffer if there are enough frames to guarantee that we push in PTS
* order
*/
while ((g_async_queue_length (vtdec->reorder_queue) >=
vtdec->reorder_queue_length) || drain || flush) {
frame = (GstVideoCodecFrame *) g_async_queue_try_pop (vtdec->reorder_queue);
/* we need to check this in case reorder_queue_length=0 (jpeg for
* example) or we're draining/flushing
*/
if (frame) {
if (flush)
gst_video_decoder_drop_frame (decoder, frame);
else
ret = gst_video_decoder_finish_frame (decoder, frame);
}
if (!frame || ret != GST_FLOW_OK)
break;
}
return ret;
}
static gboolean
parse_h264_profile_and_level_from_codec_data (GstVtdec * vtdec,
GstBuffer * codec_data, int *profile, int *level)
{
GstMapInfo map;
guint8 *data;
gint size;
gboolean ret = TRUE;
gst_buffer_map (codec_data, &map, GST_MAP_READ);
data = map.data;
size = map.size;
/* parse the avcC data */
if (size < 7)
goto avcc_too_small;
/* parse the version, this must be 1 */
if (data[0] != 1)
goto wrong_version;
/* AVCProfileIndication */
/* profile_compat */
/* AVCLevelIndication */
if (profile)
*profile = data[1];
if (level)
*level = data[3];
out:
gst_buffer_unmap (codec_data, &map);
return ret;
avcc_too_small:
GST_ELEMENT_ERROR (vtdec, STREAM, DECODE, (NULL),
("invalid codec_data buffer length"));
ret = FALSE;
goto out;
wrong_version:
GST_ELEMENT_ERROR (vtdec, STREAM, DECODE, (NULL),
("wrong avcC version in codec_data"));
ret = FALSE;
goto out;
}
static int
get_dpb_max_mb_s_from_level (GstVtdec * vtdec, int level)
{
switch (level) {
case 10:
/* 1b?? */
return 396;
case 11:
return 900;
case 12:
case 13:
case 20:
return 2376;
case 21:
return 4752;
case 22:
case 30:
return 8100;
case 31:
return 18000;
case 32:
return 20480;
case 40:
case 41:
return 32768;
case 42:
return 34816;
case 50:
return 110400;
case 51:
case 52:
return 184320;
default:
GST_ERROR_OBJECT (vtdec, "unknown level %d", level);
return -1;
}
}
static gboolean
gst_vtdec_compute_reorder_queue_length (GstVtdec * vtdec,
CMVideoCodecType cm_format, GstBuffer * codec_data)
{
if (cm_format == kCMVideoCodecType_H264) {
if (!compute_h264_decode_picture_buffer_length (vtdec, codec_data,
&vtdec->reorder_queue_length)) {
return FALSE;
}
} else {
vtdec->reorder_queue_length = 0;
}
return TRUE;
}
static gboolean
compute_h264_decode_picture_buffer_length (GstVtdec * vtdec,
GstBuffer * codec_data, int *length)
{
int profile, level;
int dpb_mb_size = 16;
int max_dpb_size_frames = 16;
int max_dpb_mb_s = -1;
int width_in_mb_s = vtdec->video_info.width / dpb_mb_size;
int height_in_mb_s = vtdec->video_info.height / dpb_mb_size;
if (!parse_h264_profile_and_level_from_codec_data (vtdec, codec_data,
&profile, &level))
return FALSE;
max_dpb_mb_s = get_dpb_max_mb_s_from_level (vtdec, level);
if (max_dpb_mb_s == -1) {
GST_ELEMENT_ERROR (vtdec, STREAM, DECODE, (NULL),
("invalid level in codec_data, could not compute max_dpb_mb_s"));
return FALSE;
}
/* this formula is specified in sections A.3.1.h and A.3.2.f of the 2009
* edition of the standard */
*length = MIN (floor (max_dpb_mb_s / (width_in_mb_s * height_in_mb_s)),
max_dpb_size_frames);
return TRUE;
}
static void
gst_vtdec_set_latency (GstVtdec * vtdec)
{
GstClockTime frame_duration = gst_util_uint64_scale (GST_SECOND,
vtdec->video_info.fps_d, vtdec->video_info.fps_n);
GstClockTime latency = frame_duration * vtdec->reorder_queue_length;
GST_INFO_OBJECT (vtdec, "setting latency frames:%d time:%" GST_TIME_FORMAT,
vtdec->reorder_queue_length, GST_TIME_ARGS (latency));
gst_video_decoder_set_latency (GST_VIDEO_DECODER (vtdec), latency, latency);
}
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