+/*****************************************************************************
+ * 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;
+}
+