[vlc-commits] demux: mp4: unify and simplify samples reading
Francois Cartegnie
git at videolan.org
Thu Jun 5 20:32:20 CEST 2014
vlc | branch: master | Francois Cartegnie <fcvlcdev at free.fr> | Thu Jun 5 20:15:26 2014 +0200| [885249c19a0b3f9b4012836bbad7330154bdc87b] | committer: Francois Cartegnie
demux: mp4: unify and simplify samples reading
> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=885249c19a0b3f9b4012836bbad7330154bdc87b
---
modules/demux/mp4/mp4.c | 159 +++++++++++++++++++++++------------------------
1 file changed, 77 insertions(+), 82 deletions(-)
diff --git a/modules/demux/mp4/mp4.c b/modules/demux/mp4/mp4.c
index 3260914..e816f3e 100644
--- a/modules/demux/mp4/mp4.c
+++ b/modules/demux/mp4/mp4.c
@@ -119,7 +119,7 @@ static void MP4_TrackUnselect(demux_t *, mp4_track_t * );
static int MP4_TrackSeek ( demux_t *, mp4_track_t *, mtime_t );
static uint64_t MP4_TrackGetPos ( mp4_track_t * );
-static uint32_t MP4_TrackSampleSize( mp4_track_t *, uint32_t * );
+static uint32_t MP4_TrackGetReadSize( mp4_track_t *, uint32_t * );
static int MP4_TrackNextSample( demux_t *, mp4_track_t *, uint32_t );
static void MP4_TrackSetELST( demux_t *, mp4_track_t *, int64_t );
@@ -863,7 +863,7 @@ static int Demux( demux_t *p_demux )
#endif
uint32_t i_nb_samples = 0;
- uint32_t i_samplessize = MP4_TrackSampleSize( tk, &i_nb_samples );
+ uint32_t i_samplessize = MP4_TrackGetReadSize( tk, &i_nb_samples );
if( i_samplessize > 0 )
{
block_t *p_block;
@@ -1565,7 +1565,7 @@ static void LoadChapterApple( demux_t *p_demux, mp4_track_t *tk )
const int64_t i_dts = MP4_TrackGetDTS( p_demux, tk );
const int64_t i_pts_delta = MP4_TrackGetPTSDelta( p_demux, tk );
uint32_t i_nb_samples = 0;
- const uint32_t i_size = MP4_TrackSampleSize( tk, &i_nb_samples );
+ const uint32_t i_size = MP4_TrackGetReadSize( tk, &i_nb_samples );
if( i_size > 0 && !stream_Seek( p_demux->s, MP4_TrackGetPos( tk ) ) )
{
@@ -3339,63 +3339,89 @@ static int MP4_TrackSeek( demux_t *p_demux, mp4_track_t *p_track,
*
*/
#define QT_V0_MAX_SAMPLES 1024
-static uint32_t MP4_TrackSampleSize( mp4_track_t *p_track, uint32_t *pi_nb_samples )
+static uint32_t MP4_TrackGetReadSize( mp4_track_t *p_track, uint32_t *pi_nb_samples )
{
- uint32_t i_size;
- MP4_Box_data_sample_soun_t *p_soun;
+ uint32_t i_size = 0;
+ *pi_nb_samples = 0;
- if( p_track->i_sample_size == 0 )
- {
- /* most simple case */
- *pi_nb_samples = 1;
- return p_track->p_sample_size[p_track->i_sample];
- }
+ if ( p_track->i_sample == p_track->i_sample_count )
+ return 0;
- if( p_track->fmt.i_cat != AUDIO_ES )
+ if ( p_track->fmt.i_cat != AUDIO_ES )
{
*pi_nb_samples = 1;
- return p_track->i_sample_size;
- }
-
- p_soun = p_track->p_sample->data.p_sample_soun;
- if( p_soun->i_qt_version == 1 )
- {
- uint32_t i_samples = p_track->chunk[p_track->i_chunk].i_sample_count;
- if( p_track->fmt.audio.i_blockalign > 1 )
- i_samples = p_soun->i_sample_per_packet;
- i_size = i_samples / p_soun->i_sample_per_packet;
- if ( UINT32_MAX / i_size >= p_soun->i_bytes_per_frame )
- i_size *= p_soun->i_bytes_per_frame;
+ if( p_track->i_sample_size == 0 ) /* all sizes are different */
+ return p_track->p_sample_size[p_track->i_sample];
else
- i_size = UINT32_MAX;
- *pi_nb_samples = i_samples;
- }
- else if( p_track->i_sample_size > 256 )
- {
- /* We do that so we don't read too much data
- * (in this case we are likely dealing with compressed data) */
- i_size = p_track->i_sample_size;
- *pi_nb_samples = 1;
+ return p_track->i_sample_size;
}
else
{
- mp4_chunk_t *p_chunk = &p_track->chunk[p_track->i_chunk];
- int64_t i_length = CLOCK_FREQ / 10;
- uint32_t i_samples = 0;
- uint32_t i_maxsamples = 0;
+ const MP4_Box_data_sample_soun_t *p_soun = p_track->p_sample->data.p_sample_soun;
+ const mp4_chunk_t *p_chunk = &p_track->chunk[p_track->i_chunk];
+ uint32_t i_max_samples = p_chunk->i_sample_count - p_chunk->i_sample + 1;
+ i_max_samples = __MIN( i_max_samples, QT_V0_MAX_SAMPLES );
+
+ /* Group audio packets so we don't call demux for single sample unit */
+ if( p_track->fmt.i_original_fourcc == VLC_CODEC_DVD_LPCM &&
+ p_soun->i_constLPCMframesperaudiopacket &&
+ p_soun->i_constbytesperaudiopacket )
+ {
+ /* uncompressed case */
+ uint32_t i_packets = i_max_samples / p_soun->i_constLPCMframesperaudiopacket;
+ if ( UINT32_MAX / p_soun->i_constbytesperaudiopacket < i_packets )
+ i_packets = UINT32_MAX / p_soun->i_constbytesperaudiopacket;
+ *pi_nb_samples = i_packets * p_soun->i_constLPCMframesperaudiopacket;
+ return i_packets * p_soun->i_constbytesperaudiopacket;
+ }
+
+ /* all samples have a different size */
+ if( p_track->i_sample_size == 0 )
+ {
+ *pi_nb_samples = 1;
+ return p_track->p_sample_size[p_track->i_sample];
+ }
+
+ if( p_soun->i_qt_version == 1 )
+ {
+ if ( p_soun->i_compressionid != 0 )
+ {
+ /* in this case we are dealing with compressed data
+ -2 in V1: additional fields are meaningless (VBR and such) */
+ i_size = p_track->i_sample_size;
+ *pi_nb_samples = 1;
+ }
+ else /* uncompressed case */
+ {
+ uint32_t i_packets;
+ if( p_track->fmt.audio.i_blockalign > 1 )
+ i_packets = 1;
+ else
+ i_packets = i_max_samples / p_soun->i_sample_per_packet;
+
+ if ( UINT32_MAX / p_soun->i_bytes_per_frame < i_packets )
+ i_packets = UINT32_MAX / p_soun->i_bytes_per_frame;
+
+ *pi_nb_samples = i_packets * p_soun->i_sample_per_packet;
+ i_size = i_packets * p_soun->i_bytes_per_frame;
+ }
+ }
+
+ /* uncompressed */
+ *pi_nb_samples = 0;
+ mtime_t i_length = CLOCK_FREQ / 10;
for( uint32_t i=p_track->i_sample; i<p_chunk->i_sample_count; i++ )
{
i_length -= CLOCK_FREQ * p_chunk->p_sample_delta_dts[i] / p_track->i_timescale;
- if ( i_length < 0 ) break;
- i_maxsamples++;
+ if ( i_length < 0 || *pi_nb_samples == QT_V0_MAX_SAMPLES )
+ break;
+ (*pi_nb_samples)++;
+ if ( p_track->i_sample_size == 0 )
+ i_size += p_track->p_sample_size[i];
+ else
+ i_size += p_track->i_sample_size;
}
-
- i_samples = __MIN( QT_V0_MAX_SAMPLES, i_samples );
- i_samples = __MIN( i_maxsamples, i_samples );
- if ( i_samples == 0 ) i_samples = 1;
- i_size = i_samples * p_track->i_sample_size;
- *pi_nb_samples = i_samples;
}
//fprintf( stderr, "size=%d\n", i_size );
@@ -3442,45 +3468,14 @@ static uint64_t MP4_TrackGetPos( mp4_track_t *p_track )
static int MP4_TrackNextSample( demux_t *p_demux, mp4_track_t *p_track, uint32_t i_samples )
{
- if( p_track->fmt.i_cat == AUDIO_ES && p_track->i_sample_size != 0 )
+ if ( UINT32_MAX - p_track->i_sample < i_samples )
{
- MP4_Box_data_sample_soun_t *p_soun;
-
- p_soun = p_track->p_sample->data.p_sample_soun;
-
- if( p_soun->i_qt_version == 1 )
- {
- /* we read chunk by chunk unless a blockalign is requested */
- if( p_track->fmt.audio.i_blockalign > 1 )
- p_track->i_sample += p_soun->i_sample_per_packet;
- else
- p_track->i_sample += p_track->chunk[p_track->i_chunk].i_sample_count;
- }
- else if( p_track->i_sample_size > 256 )
- {
- /* We do that so we don't read too much data
- * (in this case we are likely dealing with compressed data) */
- p_track->i_sample += 1;
- }
- else
- {
- /* FIXME */
- p_track->i_sample += i_samples;
- if( p_track->i_sample >
- p_track->chunk[p_track->i_chunk].i_sample_first +
- p_track->chunk[p_track->i_chunk].i_sample_count )
- {
- p_track->i_sample =
- p_track->chunk[p_track->i_chunk].i_sample_first +
- p_track->chunk[p_track->i_chunk].i_sample_count;
- }
- }
- }
- else
- {
- p_track->i_sample++;
+ p_track->i_sample = UINT32_MAX;
+ return VLC_EGENERIC;
}
+ p_track->i_sample += i_samples;
+
if( p_track->i_sample >= p_track->i_sample_count )
return VLC_EGENERIC;
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