--- /dev/null
+/*****************************************************************************
+ * mlp.c: packetize MLP/TrueHD audio
+ *****************************************************************************
+ * Copyright (C) 2008 Laurent Aimar
+ * $Id$
+ *
+ * Authors: Laurent Aimar < fenrir _AT videolan _DOT_ org >
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+/*****************************************************************************
+ * Preamble
+ *****************************************************************************/
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <vlc_common.h>
+#include <vlc_plugin.h>
+#include <vlc_codec.h>
+#include <vlc_aout.h>
+#include <vlc_block_helper.h>
+#include <vlc_bits.h>
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+static int Open ( vlc_object_t * );
+static void Close( vlc_object_t * );
+
+vlc_module_begin ()
+ set_category( CAT_SOUT )
+ set_subcategory( SUBCAT_SOUT_PACKETIZER )
+ set_description( N_("MLP/TrueHD parser") )
+ set_capability( "packetizer", 50 )
+ set_callbacks( Open, Close )
+vlc_module_end ()
+
+/*****************************************************************************
+ *
+ *****************************************************************************/
+typedef struct
+{
+ int i_type;
+ int i_rate;
+ int i_channels;
+ int i_channels_conf;
+ int i_samples;
+
+ bool b_vbr;
+ int i_bitrate;
+
+ int i_substreams;
+
+} mlp_header_t;
+
+struct decoder_sys_t
+{
+ /*
+ * Input properties
+ */
+ int i_state;
+
+ block_bytestream_t bytestream;
+
+ /*
+ * Common properties
+ */
+ audio_date_t end_date;
+
+ mtime_t i_pts;
+ int i_frame_size;
+
+ bool b_mlp;
+ mlp_header_t mlp;
+};
+
+enum {
+
+ STATE_NOSYNC,
+ STATE_SYNC,
+ STATE_HEADER,
+ STATE_NEXT_SYNC,
+ STATE_GET_DATA,
+ STATE_SEND_DATA
+};
+
+#define MLP_MAX_SUBSTREAMS (16)
+#define MLP_HEADER_SYNC (28)
+#define MLP_HEADER_SIZE (4 + MLP_HEADER_SYNC + 4 * MLP_MAX_SUBSTREAMS)
+
+static const uint8_t pu_start_code[3] = { 0xf8, 0x72, 0x6f };
+
+/****************************************************************************
+ * Local prototypes
+ ****************************************************************************/
+static block_t *Packetize( decoder_t *, block_t **pp_block );
+static int SyncInfo( const uint8_t *p_hdr, bool *pb_mlp, mlp_header_t *p_mlp );
+static int SyncInfoDolby( const uint8_t *p_buf );
+
+/*****************************************************************************
+ * Open: probe the decoder/packetizer and return score
+ *****************************************************************************/
+static int Open( vlc_object_t *p_this )
+{
+ decoder_t *p_dec = (decoder_t*)p_this;
+ decoder_sys_t *p_sys;
+
+ if( p_dec->fmt_in.i_codec != VLC_FOURCC('m','l','p',' ') )
+ return VLC_EGENERIC;
+
+ /* */
+ p_dec->p_sys = p_sys = malloc( sizeof(*p_sys) );
+ if( !p_sys )
+ return VLC_ENOMEM;
+
+ /* */
+ p_sys->i_state = STATE_NOSYNC;
+ aout_DateSet( &p_sys->end_date, 0 );
+
+ p_sys->bytestream = block_BytestreamInit();
+ p_sys->b_mlp = false;
+
+ /* Set output properties */
+ p_dec->fmt_out.i_cat = AUDIO_ES;
+ p_dec->fmt_out.i_codec = VLC_FOURCC('m','l','p',' ');
+ p_dec->fmt_out.audio.i_rate = 0;
+
+ /* Set callback */
+ p_dec->pf_packetize = Packetize;
+ return VLC_SUCCESS;
+}
+
+/****************************************************************************
+ * Packetize:
+ ****************************************************************************/
+static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
+{
+ decoder_sys_t *p_sys = p_dec->p_sys;
+ uint8_t p_header[MLP_HEADER_SIZE];
+ block_t *p_out_buffer;
+
+ /* */
+ if( !pp_block || !*pp_block )
+ return NULL;
+
+ /* */
+ if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
+ {
+ if( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED )
+ {
+ p_sys->b_mlp = false;
+ p_sys->i_state = STATE_NOSYNC;
+ block_BytestreamFlush( &p_sys->bytestream );
+ }
+ block_Release( *pp_block );
+ return NULL;
+ }
+
+ if( !aout_DateGet( &p_sys->end_date ) && !(*pp_block)->i_pts )
+ {
+ /* We've just started the stream, wait for the first PTS. */
+ block_Release( *pp_block );
+ return NULL;
+ }
+
+ block_BytestreamPush( &p_sys->bytestream, *pp_block );
+
+ for( ;; )
+ {
+ switch( p_sys->i_state )
+ {
+ case STATE_NOSYNC:
+ while( !block_PeekBytes( &p_sys->bytestream, p_header, MLP_HEADER_SIZE ) )
+ {
+ if( SyncInfo( p_header, &p_sys->b_mlp, &p_sys->mlp ) > 0 )
+ {
+ p_sys->i_state = STATE_SYNC;
+ break;
+ }
+ else if( SyncInfoDolby( p_header ) > 0 )
+ {
+ p_sys->i_state = STATE_SYNC;
+ break;
+ }
+ block_SkipByte( &p_sys->bytestream );
+ }
+ if( p_sys->i_state != STATE_SYNC )
+ {
+ block_BytestreamFlush( &p_sys->bytestream );
+
+ /* Need more data */
+ return NULL;
+ }
+
+ case STATE_SYNC:
+ /* New frame, set the Presentation Time Stamp */
+ p_sys->i_pts = p_sys->bytestream.p_block->i_pts;
+ if( p_sys->i_pts != 0 &&
+ p_sys->i_pts != aout_DateGet( &p_sys->end_date ) )
+ {
+ aout_DateSet( &p_sys->end_date, p_sys->i_pts );
+ }
+ p_sys->i_state = STATE_HEADER;
+
+ case STATE_HEADER:
+ /* Get a MLP header */
+ if( block_PeekBytes( &p_sys->bytestream, p_header, MLP_HEADER_SIZE ) )
+ {
+ /* Need more data */
+ return NULL;
+ }
+
+ /* Check if frame is valid and get frame info */
+ p_sys->i_frame_size = SyncInfoDolby( p_header );
+ if( p_sys->i_frame_size <= 0 )
+ p_sys->i_frame_size = SyncInfo( p_header, &p_sys->b_mlp, &p_sys->mlp );
+ if( p_sys->i_frame_size <= 0 )
+ {
+ msg_Dbg( p_dec, "emulated sync word" );
+ block_SkipByte( &p_sys->bytestream );
+ p_sys->b_mlp = false;
+ p_sys->i_state = STATE_NOSYNC;
+ break;
+ }
+ p_sys->i_state = STATE_NEXT_SYNC;
+
+ case STATE_NEXT_SYNC:
+ /* TODO: If pp_block == NULL, flush the buffer without checking the
+ * next sync word */
+
+ /* Check if next expected frame contains the sync word */
+ if( block_PeekOffsetBytes( &p_sys->bytestream,
+ p_sys->i_frame_size, p_header, MLP_HEADER_SIZE ) )
+ {
+ /* Need more data */
+ return NULL;
+ }
+
+ bool b_mlp = p_sys->b_mlp;
+ mlp_header_t mlp = p_sys->mlp;
+ if( SyncInfo( p_header, &b_mlp, &mlp ) <= 0 && SyncInfoDolby( p_header ) <= 0 )
+ {
+ msg_Dbg( p_dec, "emulated sync word "
+ "(no sync on following frame)" );
+ fprintf( stderr,"\n" );
+ p_sys->b_mlp = false;
+ p_sys->i_state = STATE_NOSYNC;
+ block_SkipByte( &p_sys->bytestream );
+ break;
+ }
+ p_sys->i_state = STATE_SEND_DATA;
+ break;
+
+ case STATE_GET_DATA:
+ /* Make sure we have enough data.
+ * (Not useful if we went through NEXT_SYNC) */
+ if( block_WaitBytes( &p_sys->bytestream, p_sys->i_frame_size ) )
+ {
+ /* Need more data */
+ return NULL;
+ }
+ p_sys->i_state = STATE_SEND_DATA;
+
+ case STATE_SEND_DATA:
+ /* When we reach this point we already know we have enough
+ * data available. */
+ p_out_buffer = block_New( p_dec, p_sys->i_frame_size );
+ if( !p_out_buffer )
+ return NULL;
+
+ /* Copy the whole frame into the buffer */
+ block_GetBytes( &p_sys->bytestream,
+ p_out_buffer->p_buffer, p_out_buffer->i_buffer );
+
+ /* Just ignore (E)AC3 frames */
+ if( SyncInfoDolby( p_out_buffer->p_buffer ) > 0 )
+ {
+ block_Release( p_out_buffer );
+ p_sys->i_state = STATE_NOSYNC;
+ break;
+ }
+
+ /* Setup output */
+ if( p_dec->fmt_out.audio.i_rate != p_sys->mlp.i_rate )
+ {
+ msg_Info( p_dec, "MLP channels: %d samplerate: %d",
+ p_sys->mlp.i_channels, p_sys->mlp.i_rate );
+
+ aout_DateInit( &p_sys->end_date, p_sys->mlp.i_rate );
+ aout_DateSet( &p_sys->end_date, p_sys->i_pts );
+ }
+
+ p_dec->fmt_out.audio.i_rate = p_sys->mlp.i_rate;
+ p_dec->fmt_out.audio.i_channels = p_sys->mlp.i_channels;
+ p_dec->fmt_out.audio.i_original_channels = p_sys->mlp.i_channels_conf;
+ p_dec->fmt_out.audio.i_physical_channels = p_sys->mlp.i_channels_conf & AOUT_CHAN_PHYSMASK;
+
+ p_out_buffer->i_pts = p_out_buffer->i_dts = aout_DateGet( &p_sys->end_date );
+
+ p_out_buffer->i_length =
+ aout_DateIncrement( &p_sys->end_date, p_sys->mlp.i_samples ) - p_out_buffer->i_pts;
+
+ /* Make sure we don't reuse the same pts twice */
+ if( p_sys->i_pts == p_sys->bytestream.p_block->i_pts )
+ p_sys->i_pts = p_sys->bytestream.p_block->i_pts = 0;
+
+ /* So p_block doesn't get re-added several times */
+ *pp_block = block_BytestreamPop( &p_sys->bytestream );
+
+ p_sys->i_state = STATE_NOSYNC;
+
+ return p_out_buffer;
+ }
+ }
+
+ return NULL;
+}
+
+/*****************************************************************************
+ * Close:
+ *****************************************************************************/
+static void Close( vlc_object_t *p_this )
+{
+ decoder_t *p_dec = (decoder_t*)p_this;
+ decoder_sys_t *p_sys = p_dec->p_sys;
+
+ block_BytestreamRelease( &p_sys->bytestream );
+
+ free( p_sys );
+}
+
+/**
+ * It parse MLP sync info.
+ *
+ * TODO handle CRC (at offset 26)
+ */
+
+static int TrueHdChannels( int i_map )
+{
+ static const uint8_t pu_thd[13] =
+ {
+ 2, 1, 1, 2, 2, 2, 2, 1, 1, 2, 2, 1, 1
+ };
+ int i_count = 0;
+
+ for( int i = 0; i < 13; i++ )
+ {
+ if( i_map & (1<<i) )
+ i_count += pu_thd[i];
+ }
+ return i_count;
+}
+
+static int MlpParse( mlp_header_t *p_mlp, const uint8_t p_hdr[MLP_HEADER_SYNC] )
+{
+ bs_t s;
+
+ assert( !memcmp( p_hdr, pu_start_code, 3 ) );
+
+ /* TODO Checksum ? */
+
+ /* */
+ bs_init( &s, &p_hdr[3], MLP_HEADER_SYNC - 3 );
+
+ /* Stream type */
+ p_mlp->i_type = bs_read( &s, 8 );
+ int i_rate_idx1;
+
+ if( p_mlp->i_type == 0xbb ) /* MLP */
+ {
+ static const unsigned pu_channels[32] = {
+ 1, 2, 3, 4, 3, 4, 5, 3, 4, 5, 4, 5, 6, 4, 5, 4,
+ 5, 6, 5, 5, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ };
+
+ bs_skip( &s, 4 + 4 );
+
+ i_rate_idx1 = bs_read( &s, 4 );
+ const int i_rate_idx2 = bs_read( &s, 4 );
+
+ bs_skip( &s, 11 );
+
+ const int i_channel_idx = bs_read( &s, 5 );
+ p_mlp->i_channels = pu_channels[i_channel_idx];
+ }
+ else if( p_mlp->i_type == 0xba ) /* True HD */
+ {
+ i_rate_idx1 = bs_read( &s, 4 );
+
+ bs_skip( &s, 8 );
+
+ const int i_channel1 = bs_read( &s, 5 );
+
+ bs_skip( &s, 2 );
+
+ const int i_channel2 = bs_read( &s, 13 );
+ if( i_channel2 )
+ p_mlp->i_channels = TrueHdChannels( i_channel2 );
+ else
+ p_mlp->i_channels = TrueHdChannels( i_channel1 );
+ }
+ else
+ {
+ return VLC_EGENERIC;
+ }
+
+ if( i_rate_idx1 == 0x0f )
+ p_mlp->i_rate = 0;
+ else
+ p_mlp->i_rate = ( ( i_rate_idx1 & 0x8 ) ? 44100 : 48000 ) << (i_rate_idx1 & 0x7);
+ p_mlp->i_channels_conf = 0; /* TODO ? */
+
+ p_mlp->i_samples = 40 << ( i_rate_idx1 & 0x07 );
+
+ bs_skip( &s, 48 );
+
+ p_mlp->b_vbr = bs_read( &s, 1 );
+ p_mlp->i_bitrate = ( bs_read( &s, 15 ) * p_mlp->i_rate + 8) / 16;
+
+ p_mlp->i_substreams = bs_read( &s, 4 );
+ bs_skip( &s, 4 + 11 * 8 );
+
+ //fprintf( stderr, "i_samples = %d channels:%d rate:%d bitsrate=%d substreams=%d\n",
+ // p_mlp->i_samples, p_mlp->i_channels, p_mlp->i_rate, p_mlp->i_bitrate, p_mlp->i_substreams );
+ return VLC_SUCCESS;
+}
+
+static int SyncInfo( const uint8_t *p_hdr, bool *pb_mlp, mlp_header_t *p_mlp )
+{
+ /* Check major sync presence */
+ const bool b_has_sync = !memcmp( &p_hdr[4], pu_start_code, 3 );
+
+ /* Wait for a major sync */
+ if( !b_has_sync && !*pb_mlp )
+ return 0;
+
+ /* Parse major sync if present */
+ if( b_has_sync )
+ {
+ *pb_mlp = !MlpParse( p_mlp, &p_hdr[4] );
+
+ if( !*pb_mlp )
+ return 0;
+ }
+
+ /* Check parity TODO even with major sync */
+ if( 1 )
+ {
+ int i_tmp = 0 ^ p_hdr[0] ^ p_hdr[1] ^ p_hdr[2] ^ p_hdr[3];
+ const uint8_t *p = &p_hdr[4 + ( b_has_sync ? 28 : 0 )];
+
+ for( int i = 0; i < p_mlp->i_substreams; i++ )
+ {
+ i_tmp ^= *p++;
+ i_tmp ^= *p++;
+ if( p[-2] & 0x80 )
+ {
+ i_tmp ^= *p++;
+ i_tmp ^= *p++;
+ }
+ }
+ i_tmp = ( i_tmp >> 4 ) ^ i_tmp;
+
+ if( ( i_tmp & 0x0f ) != 0x0f )
+ return 0;
+ }
+
+ /* */
+ const int i_word = ( ( p_hdr[0] << 8 ) | p_hdr[1] ) & 0xfff;
+ return i_word * 2;
+}
+
+/**
+ * It returns the size of an AC3 frame (or 0 if invalid)
+ */
+static int GetAc3Size( const uint8_t *p_buf )
+{
+ static const int pi_rate[] = { 32, 40, 48, 56, 64, 80, 96, 112,
+ 128, 160, 192, 224, 256, 320, 384, 448,
+ 512, 576, 640 };
+ /* */
+ const int i_frmsizecod = p_buf[4] & 63;
+ if( i_frmsizecod >= 38 )
+ return 0;
+
+ const int bitrate = pi_rate[i_frmsizecod >> 1];
+
+ switch( p_buf[4] & 0xc0 )
+ {
+ case 0:
+ return 4 * bitrate;
+ case 0x40:
+ return 2 * (320 * bitrate / 147 + (i_frmsizecod & 1));
+ case 0x80:
+ return 6 * bitrate;
+ default:
+ return 0;
+ }
+}
+
+/**
+ * It return the size of a EAC3 frame (or 0 if invalid)
+ */
+static int GetEac3Size( const uint8_t *p_buf )
+{
+ int i_frame_size;
+ int i_bytes;
+
+ i_frame_size = ( ( p_buf[2] << 8 ) | p_buf[3] ) & 0x7ff;
+ if( i_frame_size < 2 )
+ return 0;
+ i_bytes = 2 * ( i_frame_size + 1 );
+
+ return i_bytes;
+}
+
+/**
+ * It returns the size of an AC3/EAC3 frame (or 0 if invalid)
+ */
+static int SyncInfoDolby( const uint8_t *p_buf )
+{
+ int bsid;
+
+ /* Check synword */
+ if( p_buf[0] != 0x0b || p_buf[1] != 0x77 )
+ return 0;
+
+ /* Check bsid */
+ bsid = p_buf[5] >> 3;
+ if( bsid > 16 )
+ return 0;
+
+ if( bsid <= 10 )
+ return GetAc3Size( p_buf );
+ else
+ return GetEac3Size( p_buf );
+}
+
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