int libavsmash_video_get_cts
(
libavsmash_video_decode_handler_t *vdhp,
uint32_t coded_sample_number,
uint64_t *cts
)
{
return lsmash_get_cts_from_media_timeline( vdhp->root, vdhp->track_id, coded_sample_number, cts );
}
/* This function assume that no audio frame reorderings in composition timeline. */
static uint64_t libavsmash_audio_fetch_min_cts
(
libavsmash_audio_decode_handler_t *adhp
)
{
if( !adhp || lsmash_get_cts_from_media_timeline( adhp->root, adhp->track_id, 1, &adhp->min_cts ) < 0 )
return UINT64_MAX;
return adhp->min_cts;
}
int libavsmash_video_setup_timestamp_info
(
libavsmash_video_decode_handler_t *vdhp,
libavsmash_video_output_handler_t *vohp,
int64_t *framerate_num,
int64_t *framerate_den
)
{
int err = -1;
uint64_t media_timescale = lsmash_get_media_timescale( vdhp->root, vdhp->track_id );
uint64_t media_duration = lsmash_get_media_duration_from_media_timeline( vdhp->root, vdhp->track_id );
if( media_duration == 0 )
media_duration = INT32_MAX;
if( vdhp->sample_count == 1 )
{
/* Calculate average framerate. */
reduce_fraction( &media_timescale, &media_duration );
*framerate_num = (int64_t)media_timescale;
*framerate_den = (int64_t)media_duration;
err = 0;
goto setup_finish;
}
lw_log_handler_t *lhp = &vdhp->config.lh;
lsmash_media_ts_list_t ts_list;
if( lsmash_get_media_timestamps( vdhp->root, vdhp->track_id, &ts_list ) < 0 )
{
lw_log_show( lhp, LW_LOG_ERROR, "Failed to get timestamps." );
goto setup_finish;
}
if( ts_list.sample_count != vdhp->sample_count )
{
lw_log_show( lhp, LW_LOG_ERROR, "Failed to count number of video samples." );
goto setup_finish;
}
uint32_t composition_sample_delay;
if( lsmash_get_max_sample_delay( &ts_list, &composition_sample_delay ) < 0 )
{
lsmash_delete_media_timestamps( &ts_list );
lw_log_show( lhp, LW_LOG_ERROR, "Failed to get composition delay." );
goto setup_finish;
}
if( composition_sample_delay )
{
/* Consider composition order for keyframe detection.
* Note: sample number for L-SMASH is 1-origin. */
vdhp->order_converter = (order_converter_t *)lw_malloc_zero( (ts_list.sample_count + 1) * sizeof(order_converter_t) );
if( !vdhp->order_converter )
{
lsmash_delete_media_timestamps( &ts_list );
lw_log_show( lhp, LW_LOG_ERROR, "Failed to allocate memory." );
goto setup_finish;
}
for( uint32_t i = 0; i < ts_list.sample_count; i++ )
ts_list.timestamp[i].dts = i + 1;
lsmash_sort_timestamps_composition_order( &ts_list );
for( uint32_t i = 0; i < ts_list.sample_count; i++ )
vdhp->order_converter[i + 1].composition_to_decoding = (uint32_t)ts_list.timestamp[i].dts;
}
/* Calculate average framerate. */
uint64_t largest_cts = ts_list.timestamp[0].cts;
uint64_t second_largest_cts = 0;
uint64_t first_duration = ts_list.timestamp[1].cts - ts_list.timestamp[0].cts;
uint64_t composition_timebase = first_duration;
int strict_cfr = 1;
for( uint32_t i = 1; i < ts_list.sample_count; i++ )
{
uint64_t duration = ts_list.timestamp[i].cts - ts_list.timestamp[i - 1].cts;
if( duration == 0 )
{
lsmash_delete_media_timestamps( &ts_list );
lw_log_show( lhp, LW_LOG_WARNING, "Detected CTS duplication at frame %" PRIu32, i );
err = 0;
goto setup_finish;
}
if( strict_cfr && duration != first_duration )
strict_cfr = 0;
composition_timebase = get_gcd( composition_timebase, duration );
second_largest_cts = largest_cts;
largest_cts = ts_list.timestamp[i].cts;
}
uint64_t reduce = reduce_fraction( &media_timescale, &composition_timebase );
uint64_t composition_duration = ((largest_cts - ts_list.timestamp[0].cts) + (largest_cts - second_largest_cts)) / reduce;
lsmash_delete_media_timestamps( &ts_list );
double avg_frame_rate = (vdhp->sample_count * ((double)media_timescale / composition_duration));
if( strict_cfr || !lw_try_rational_framerate( avg_frame_rate, framerate_num, framerate_den, composition_timebase ) )
{
uint64_t num = (uint64_t)(avg_frame_rate * composition_timebase + 0.5);
uint64_t den = composition_timebase;
if( num && den )
reduce_fraction( &num, &den );
else
{
num = 1;
den = 1;
}
*framerate_num = (int64_t)num;
*framerate_den = (int64_t)den;
}
err = 0;
setup_finish:;
if( vohp->vfr2cfr )
{
/* Override average framerate by specified output constant framerate. */
*framerate_num = (int64_t)vohp->cfr_num;
*framerate_den = (int64_t)vohp->cfr_den;
vohp->frame_count = ((double)vohp->cfr_num / vohp->cfr_den)
* ((double)media_duration / media_timescale)
+ 0.5;
}
else
vohp->frame_count = libavsmash_video_get_sample_count( vdhp );
uint32_t min_cts_sample_number = get_decoding_sample_number( vdhp->order_converter, 1 );
vdhp->config.error = lsmash_get_cts_from_media_timeline( vdhp->root, vdhp->track_id, min_cts_sample_number, &vdhp->min_cts );
return err;
}
