[vlc-devel] commit: Added A52 capability to es demuxer. (Laurent Aimar )
git version control
git at videolan.org
Fri Sep 12 22:07:02 CEST 2008
vlc | branch: master | Laurent Aimar <fenrir at videolan.org> | Fri Sep 12 21:29:22 2008 +0200| [eb516599de5bfa74d1a996642aa0e402121e252a] | committer: Laurent Aimar
Added A52 capability to es demuxer.
> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=eb516599de5bfa74d1a996642aa0e402121e252a
---
modules/demux/mpeg/es.c | 196 +++++++++++++++++++++++++++++++++++++++++++---
1 files changed, 183 insertions(+), 13 deletions(-)
diff --git a/modules/demux/mpeg/es.c b/modules/demux/mpeg/es.c
index 5b5b8d7..edfe49a 100644
--- a/modules/demux/mpeg/es.c
+++ b/modules/demux/mpeg/es.c
@@ -45,8 +45,8 @@ static void Close( vlc_object_t * );
vlc_module_begin();
set_category( CAT_INPUT );
set_subcategory( SUBCAT_INPUT_DEMUX );
- set_description( N_("MPEG-I/II/4 audio" ) );
- set_capability( "demux", 100 );
+ set_description( N_("MPEG-I/II/4 / A52 audio" ) );
+ set_capability( "demux", 155 );
set_callbacks( Open, Close );
add_shortcut( "mpga" );
@@ -56,8 +56,8 @@ vlc_module_begin();
add_shortcut( "mp4a" );
add_shortcut( "aac" );
- //add_shortcut( "ac3" );
- //add_shortcut( "a52" );
+ add_shortcut( "ac3" );
+ add_shortcut( "a52" );
vlc_module_end();
/*****************************************************************************
@@ -69,6 +69,7 @@ static int Control( demux_t *, int, va_list );
typedef struct
{
vlc_fourcc_t i_codec;
+ bool b_use_word;
const char *psz_name;
int (*pf_probe)( demux_t *p_demux, int64_t *pi_offset );
int (*pf_init)( demux_t *p_demux );
@@ -87,6 +88,7 @@ struct demux_sys_t
mtime_t i_time_offset;
int64_t i_bytes;
+ bool b_big_endian;
bool b_estimate_bitrate;
int i_bitrate_avg; /* extracted from Xing header */
@@ -106,19 +108,21 @@ struct demux_sys_t
} xing;
};
-#define FCC_MPGA VLC_FOURCC( 'm', 'p', 'g', 'a' )
-
static int MpgaProbe( demux_t *p_demux, int64_t *pi_offset );
static int MpgaInit( demux_t *p_demux );
static int AacProbe( demux_t *p_demux, int64_t *pi_offset );
static int AacInit( demux_t *p_demux );
+static int A52Probe( demux_t *p_demux, int64_t *pi_offset );
+static int A52Init( demux_t *p_demux );
+
static const codec_t p_codec[] = {
- { VLC_FOURCC( 'm', 'p', '4', 'a' ), "mp4 audio", AacProbe, AacInit },
- { VLC_FOURCC( 'm', 'p', 'g', 'a' ), "mpeg audio", MpgaProbe, MpgaInit },
+ { VLC_FOURCC( 'm', 'p', '4', 'a' ), false, "mp4 audio", AacProbe, AacInit },
+ { VLC_FOURCC( 'm', 'p', 'g', 'a' ), false, "mpeg audio", MpgaProbe, MpgaInit },
+ { VLC_FOURCC( 'a', '5', '2', ' ' ), true, "a52 audio", A52Probe, A52Init },
- { 0, NULL, NULL, NULL }
+ { 0, false, NULL, NULL, NULL }
};
static inline decoder_t *demux_PacketizerNew( demux_t *p_demux, int i_cat, vlc_fourcc_t i_codec, const char *psz_msg )
@@ -182,6 +186,7 @@ static int Open( vlc_object_t * p_this )
p_sys->i_stream_offset = i_offset;
p_sys->b_estimate_bitrate = true;
p_sys->i_bitrate_avg = 0;
+ p_sys->b_big_endian = false;
if( stream_Seek( p_demux->s, p_sys->i_stream_offset ) )
{
@@ -216,9 +221,34 @@ static int Demux( demux_t *p_demux )
demux_sys_t *p_sys = p_demux->p_sys;
block_t *p_block_in, *p_block_out;
+ if( p_sys->codec.b_use_word )
+ {
+ /* Make sure we are word aligned */
+ int64_t i_pos = stream_Tell( p_demux->s );
+ if( i_pos % 2 )
+ stream_Read( p_demux->s, NULL, 1 );
+ }
+
if( ( p_block_in = stream_Block( p_demux->s, p_sys->i_packet_size ) ) == NULL )
return 0;
+ if( p_sys->codec.b_use_word && !p_sys->b_big_endian && p_block_in->i_buffer > 0 )
+ {
+ /* Convert to big endian */
+#ifdef HAVE_SWAB
+ swab( p_block_in->p_buffer, p_block_in->p_buffer, p_block_in->i_buffer );
+#else
+ uint8_t *p_tmp = p_block_in->p_buffer;
+ for( int i = p_block_in->i_buffer / 2 ; i-- ; )
+ {
+ uint8_t tmp = p_tmp[0];
+ p_tmp[0] = p_tmp[1];
+ p_tmp[1] = tmp;
+ p_tmp += 2;
+ }
+#endif
+ }
+
p_block_in->i_pts = p_block_in->i_dts = p_sys->b_start || p_sys->b_initial_sync_failed ? 1 : 0;
p_sys->b_initial_sync_failed = p_sys->b_start; /* Only try to resync once */
@@ -361,7 +391,7 @@ static int Control( demux_t *p_demux, int i_query, va_list args )
/*****************************************************************************
* Mpeg I/II Audio
*****************************************************************************/
-static int CheckSyncMpga( const uint8_t *p_peek )
+static int MpgaCheckSync( const uint8_t *p_peek )
{
uint32_t h = GetDWBE( p_peek );
@@ -412,7 +442,7 @@ static int MpgaProbe( demux_t *p_demux, int64_t *pi_offset )
if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
return VLC_EGENERIC;
- if( !CheckSyncMpga( p_peek ) )
+ if( !MpgaCheckSync( p_peek ) )
{
bool b_ok = false;
int i_peek;
@@ -423,7 +453,7 @@ static int MpgaProbe( demux_t *p_demux, int64_t *pi_offset )
i_peek = stream_Peek( p_demux->s, &p_peek, 8096 );
while( i_peek > 4 )
{
- if( CheckSyncMpga( p_peek ) )
+ if( MpgaCheckSync( p_peek ) )
{
b_ok = true;
break;
@@ -476,7 +506,7 @@ static int MpgaInit( demux_t *p_demux )
return VLC_SUCCESS;
const uint32_t header = GetDWBE( p_peek );
- if( !CheckSyncMpga( p_peek ) )
+ if( !MpgaCheckSync( p_peek ) )
return VLC_SUCCESS;
/* Xing header */
@@ -568,3 +598,143 @@ static int AacInit( demux_t *p_demux )
return VLC_SUCCESS;
}
+/*****************************************************************************
+ * Wav header skipper
+ *****************************************************************************/
+#define WAV_PROBE_SIZE (512*1024)
+static int WavSkipHeader( demux_t *p_demux, int *pi_skip )
+{
+ const uint8_t *p_peek;
+ int i_peek = 0;
+
+ /* */
+ *pi_skip = 0;
+
+ /* Check if we are dealing with a WAV file */
+ if( stream_Peek( p_demux->s, &p_peek, 12+8 ) != 12 + 8 )
+ return VLC_SUCCESS;
+
+ if( memcmp( p_peek, "RIFF", 4 ) || memcmp( &p_peek[8], "WAVE", 4 ) )
+ return VLC_SUCCESS;
+
+ /* Find the wave format header */
+ i_peek = 12 + 8;
+ while( memcmp( p_peek + i_peek - 8, "fmt ", 4 ) )
+ {
+ uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
+ if( i_len > WAV_PROBE_SIZE || i_peek + i_len > WAV_PROBE_SIZE )
+ return VLC_EGENERIC;
+
+ i_peek += i_len + 8;
+ if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
+ return VLC_EGENERIC;
+ }
+
+ /* Sanity check the wave format header */
+ uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
+ if( i_len > WAV_PROBE_SIZE )
+ return VLC_EGENERIC;
+
+ i_peek += i_len + 8;
+ if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
+ return VLC_EGENERIC;
+ if( GetWLE( p_peek + i_peek - i_len - 8 /* wFormatTag */ ) !=
+ 1 /* WAVE_FORMAT_PCM */ )
+ return VLC_EGENERIC;
+ if( GetWLE( p_peek + i_peek - i_len - 6 /* nChannels */ ) != 2 )
+ return VLC_EGENERIC;
+ if( GetDWLE( p_peek + i_peek - i_len - 4 /* nSamplesPerSec */ ) !=
+ 44100 )
+ return VLC_EGENERIC;
+
+ /* Skip the wave header */
+ while( memcmp( p_peek + i_peek - 8, "data", 4 ) )
+ {
+ uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
+ if( i_len > WAV_PROBE_SIZE || i_peek + i_len > WAV_PROBE_SIZE )
+ return VLC_EGENERIC;
+
+ i_peek += i_len + 8;
+ if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
+ return VLC_EGENERIC;
+ }
+ *pi_skip = i_peek;
+ return VLC_SUCCESS;
+}
+
+/*****************************************************************************
+ * A52
+ *****************************************************************************/
+static bool A52CheckSync( const uint8_t *p_peek, bool *p_big_endian )
+{
+ /* Little endian version of the bitstream */
+ if( p_peek[0] == 0x77 && p_peek[1] == 0x0b &&
+ p_peek[4] < 0x60 /* bsid < 12 */ )
+ {
+ *p_big_endian = false;
+ return true;
+ }
+ /* Big endian version of the bitstream */
+ else if( p_peek[0] == 0x0b && p_peek[1] == 0x77 &&
+ p_peek[5] < 0x60 /* bsid < 12 */ )
+ {
+ *p_big_endian = true;
+ return true;
+ }
+
+ return false;
+}
+
+static int A52Probe( demux_t *p_demux, int64_t *pi_offset )
+{
+ bool b_forced_demux;
+ bool b_big_endian;
+
+ int64_t i_offset;
+ const uint8_t *p_peek;
+ int i_skip;
+
+ b_forced_demux = demux_IsForced( p_demux, "a52" ) ||
+ demux_IsForced( p_demux, "ac3" );
+
+ i_offset = stream_Tell( p_demux->s );
+
+ if( WavSkipHeader( p_demux, &i_skip ) )
+ {
+ if( !b_forced_demux )
+ return VLC_EGENERIC;
+ }
+
+ /* peek the begining (10 is for a52 header) */
+ if( stream_Peek( p_demux->s, &p_peek, i_skip + 10 ) < i_skip + 10 )
+ {
+ msg_Err( p_demux, "cannot peek" );
+ return VLC_EGENERIC;
+ }
+ if( !A52CheckSync( &p_peek[i_skip], &b_big_endian ) )
+ {
+ if( !b_forced_demux )
+ return VLC_EGENERIC;
+ }
+
+ *pi_offset = i_offset + i_skip;
+ return VLC_SUCCESS;
+}
+
+static int A52Init( demux_t *p_demux )
+{
+ demux_sys_t *p_sys = p_demux->p_sys;
+
+ p_sys->b_big_endian = false;
+ p_sys->i_packet_size = 1024;
+
+ const uint8_t *p_peek;
+
+ /* peek the begining (10 is for a52 header) */
+ if( stream_Peek( p_demux->s, &p_peek, 10 ) >= 10 )
+ {
+ A52CheckSync( p_peek, &p_sys->b_big_endian );
+ }
+ return VLC_SUCCESS;
+}
+
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