/****************************************************************************
* DecodeBlock: the whole thing
****************************************************************************/
static block_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
{
decoder_sys_t *p_sys = p_dec->p_sys;
uint8_t p_header[DTS_HEADER_SIZE];
uint8_t *p_buf;
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->i_state = STATE_NOSYNC;
block_BytestreamEmpty( &p_sys->bytestream );
}
date_Set( &p_sys->end_date, 0 );
block_Release( *pp_block );
return NULL;
}
if( !date_Get( &p_sys->end_date ) && (*pp_block)->i_pts <= VLC_TS_INVALID )
{
/* We've just started the stream, wait for the first PTS. */
block_Release( *pp_block );
return NULL;
}
block_BytestreamPush( &p_sys->bytestream, *pp_block );
while( 1 )
{
switch( p_sys->i_state )
{
case STATE_NOSYNC:
/* Look for sync code - should be 0x7ffe8001 */
while( block_PeekBytes( &p_sys->bytestream, p_header, 6 )
== VLC_SUCCESS )
{
if( SyncCode( p_header ) == VLC_SUCCESS )
{
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 > VLC_TS_INVALID &&
p_sys->i_pts != date_Get( &p_sys->end_date ) )
{
date_Set( &p_sys->end_date, p_sys->i_pts );
}
p_sys->i_state = STATE_HEADER;
case STATE_HEADER:
/* Get DTS frame header (DTS_HEADER_SIZE bytes) */
if( block_PeekBytes( &p_sys->bytestream, p_header,
DTS_HEADER_SIZE ) != VLC_SUCCESS )
{
/* Need more data */
return NULL;
}
/* Check if frame is valid and get frame info */
p_sys->i_frame_size = SyncInfo( p_header,
&p_sys->b_dts_hd,
&p_sys->i_channels,
&p_sys->i_channels_conf,
&p_sys->i_rate,
&p_sys->i_bit_rate,
&p_sys->i_frame_length );
if( !p_sys->i_frame_size )
{
msg_Dbg( p_dec, "emulated sync word" );
block_SkipByte( &p_sys->bytestream );
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, 6 )
!= VLC_SUCCESS )
{
/* Need more data */
return NULL;
}
if( p_sys->b_packetizer &&
p_header[0] == 0 && p_header[1] == 0 )
{
/* DTS wav files and audio CD's use stuffing */
p_sys->i_state = STATE_SEND_DATA;
break;
}
if( SyncCode( p_header ) != VLC_SUCCESS )
{
msg_Dbg( p_dec, "emulated sync word "
"(no sync on following frame): %2.2x%2.2x%2.2x%2.2x",
(int)p_header[0], (int)p_header[1],
(int)p_header[2], (int)p_header[3] );
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 ) != VLC_SUCCESS )
{
/* Need more data */
return NULL;
}
p_sys->i_state = STATE_SEND_DATA;
case STATE_SEND_DATA:
if( p_sys->b_dts_hd )
{
/* Ignore DTS-HD */
block_SkipBytes( &p_sys->bytestream, p_sys->i_frame_size );
p_sys->i_state = STATE_NOSYNC;
break;
}
if( !(p_buf = GetOutBuffer( p_dec, &p_out_buffer )) )
{
//p_dec->b_error = true;
return NULL;
}
/* Copy the whole frame into the buffer. When we reach this point
* we already know we have enough data available. */
block_GetBytes( &p_sys->bytestream,
p_buf, __MIN( p_sys->i_frame_size, p_out_buffer->i_buffer ) );
/* 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 = VLC_TS_INVALID;
p_sys->i_state = STATE_NOSYNC;
/* So p_block doesn't get re-added several times */
*pp_block = block_BytestreamPop( &p_sys->bytestream );
return p_out_buffer;
}
}
return NULL;
}
/***
* Bytestream synchronizer
* maps [Bytes] -> DataUnit
*/
static block_t *dirac_DoSync( decoder_t *p_dec )
{
decoder_sys_t *p_sys = p_dec->p_sys;
parse_info_t pu;
static const uint8_t p_parsecode[4] = {'B','B','C','D'};
do {
switch( p_sys->i_state )
{
case NOT_SYNCED:
{
if( VLC_SUCCESS !=
block_FindStartcodeFromOffset( &p_sys->bytestream, &p_sys->i_offset, p_parsecode, 4 ) )
{
/* p_sys->i_offset will have been set to:
* end of bytestream - amount of prefix found
* can resume search from this point when more data arrives */
return NULL;
}
/* candidate parse_code_prefix has been found at p_sys->i_offset */
if( VLC_SUCCESS != block_PeekOffsetBytes( &p_sys->bytestream, p_sys->i_offset + 12, NULL, 0 ) )
{
/* insufficient data has been accumulated to fully extract
* a parse_info header. exit for now in the hope of more
* data later to retry at exactly the same point */
return NULL;
}
p_sys->i_state = TRY_SYNC;
break; /* candidate found, try to sync */
}
case SYNCED: /* -> TRY_SYNC | NOT_SYNCED */
/* sanity: can only reach this after having extracted a DU,
* which causes data to be consumed and local i_offset to be reset */
assert( p_sys->i_offset == 0 );
if( VLC_SUCCESS != block_PeekOffsetBytes( &p_sys->bytestream, 12, NULL, 0 ) )
{
/* insufficient data has been accumulated to fully extract
* a parse_info header, retry later */
return NULL;
}
if( !dirac_UnpackParseInfo( &pu, &p_sys->bytestream, 0 )
|| !pu.u_next_offset || (p_sys->u_last_npo != pu.u_prev_offset) )
{
/* !a: not a valid parse info.
* !pu.u_next_offset: don't know the length of the data unit
* search for the next one that points back
* to this one to determine length.
* (p_sys->u_last_npo != pu.u_prev_offset): some desync
*/
p_sys->i_state = NOT_SYNCED;
break;
}
if( pu.u_next_offset > 1024*1024 )
{
/* sanity check for erronious hugs next_parse_offsets
* (eg, 2^32-1) that would cause a very long wait
* and large space consumption: fall back to try sync */
p_sys->i_state = TRY_SYNC;
break;
}
/* check that the start of the next data unit is avaliable */
if( VLC_SUCCESS !=
block_PeekOffsetBytes( &p_sys->bytestream, pu.u_next_offset + 12, NULL, 0 ) )
{
return NULL; /* retry later */
}
/* attempt to syncronise backwards from pu.u_next_offset */
p_sys->i_offset = pu.u_next_offset;
/* fall through */
case TRY_SYNC: /* -> SYNCED | NOT_SYNCED */
{
if( !p_sys->i_offset )
goto sync_fail; /* if a is at start of bytestream, b can't be in buffer */
parse_info_t pu_a;
bool a = dirac_UnpackParseInfo( &pu_a, &p_sys->bytestream, p_sys->i_offset );
if( !a || (pu_a.u_prev_offset > p_sys->i_offset) )
goto sync_fail; /* b lies beyond start of bytestream: can't sync */
if( !pu_a.u_prev_offset )
{
if( p_sys->i_state == TRY_SYNC )
{
goto sync_fail; /* can't find different pu_b from pu_a */
}
/* state == SYNCED: already know where pu_b is.
* pu_a has probably been inserted by something that doesn't
* know what the last next_parse_offset was */
pu_a.u_prev_offset = pu.u_next_offset;
}
parse_info_t *pu_b = &pu;
bool b = dirac_UnpackParseInfo( pu_b, &p_sys->bytestream, p_sys->i_offset - pu_a.u_prev_offset );
if( !b || (pu_b->u_next_offset && pu_a.u_prev_offset != pu_b->u_next_offset) )
{
/* if pu_b->u_next_offset = 0, have to assume we've synced, ie,
* just rely on finding a valid pu_b from pu_a. */
goto sync_fail;
}
p_sys->u_last_npo = pu_b->u_next_offset;
if( !pu_b->u_next_offset ) pu_b->u_next_offset = pu_a.u_prev_offset;
/* offset was pointing at pu_a, rewind to point at pu_b */
p_sys->i_offset -= pu_a.u_prev_offset;
p_sys->i_state = SYNCED;
break;
}
sync_fail:
if( p_sys->i_state == SYNCED ) p_sys->i_offset = 0;
p_sys->i_offset++;
p_sys->i_state = NOT_SYNCED;
break; /* find somewhere else to try again */
default:;
}
} while( SYNCED != p_sys->i_state );
/*
* synced, attempt to extract a data unit
*/
/* recover any timestamps from the data that is about to be flushed */
dirac_RecoverTimestamps( p_dec, p_sys->i_offset );
/* flush everything up to the start of the DU */
block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
block_BytestreamFlush( &p_sys->bytestream );
p_sys->i_offset = 0;
/* setup the data unit buffer */
block_t *p_block = block_New( p_dec, pu.u_next_offset );
if( !p_block )
return NULL;
p_block->i_pts = p_sys->i_sync_pts;
p_block->i_dts = p_sys->i_sync_dts;
p_sys->i_sync_pts = p_sys->i_sync_dts = VLC_TS_INVALID;
/* recover any new timestamps from the data that is about to be consumed */
dirac_RecoverTimestamps( p_dec, p_sys->i_offset );
block_GetBytes( &p_sys->bytestream, p_block->p_buffer, p_block->i_buffer );
/* save parse offset in private area for later use */
dirac_block_encap_t *p_dbe = dirac_NewBlockEncap( &p_block );
if( p_dbe ) p_dbe->u_last_next_offset = pu.u_next_offset;
return p_block;
}
static block_t *PacketizeBlock( decoder_t *p_dec, block_t **pp_block )
{
decoder_sys_t *p_sys = p_dec->p_sys;
uint8_t p_header[VLC_A52_HEADER_SIZE];
block_t *p_out_buffer;
block_t *p_block = pp_block ? *pp_block : NULL;
if( p_block )
{
if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY | BLOCK_FLAG_CORRUPTED) )
{
/* First always drain complete blocks before discontinuity */
block_t *p_drain = PacketizeBlock( p_dec, NULL );
if(p_drain)
return p_drain;
PacketizeFlush( p_dec );
if( p_block->i_flags & BLOCK_FLAG_CORRUPTED )
{
block_Release( p_block );
return NULL;
}
}
if( !date_Get( &p_sys->end_date ) && p_block->i_pts <= VLC_TS_INVALID)
{
/* We've just started the stream, wait for the first PTS. */
block_Release( p_block );
return NULL;
}
block_BytestreamPush( &p_sys->bytestream, p_block );
}
while( 1 )
{
switch( p_sys->i_state )
{
case STATE_NOSYNC:
while( block_PeekBytes( &p_sys->bytestream, p_header, 2 )
== VLC_SUCCESS )
{
if( p_header[0] == 0x0b && p_header[1] == 0x77 )
{
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 > VLC_TS_INVALID &&
p_sys->i_pts != date_Get( &p_sys->end_date ) )
{
date_Set( &p_sys->end_date, p_sys->i_pts );
}
p_sys->i_state = STATE_HEADER;
case STATE_HEADER:
/* Get A/52 frame header (VLC_A52_HEADER_SIZE bytes) */
if( block_PeekBytes( &p_sys->bytestream, p_header,
VLC_A52_HEADER_SIZE ) != VLC_SUCCESS )
{
/* Need more data */
return NULL;
}
/* Check if frame is valid and get frame info */
vlc_a52_header_t a52;
if( vlc_a52_header_Parse( &a52, p_header, VLC_A52_HEADER_SIZE ) )
{
msg_Dbg( p_dec, "emulated sync word" );
block_SkipByte( &p_sys->bytestream );
p_sys->i_state = STATE_NOSYNC;
break;
}
if( a52.b_eac3 && a52.eac3.strmtyp != EAC3_STRMTYP_INDEPENDENT )
{
/* Use the channel configuration of the independent stream */
p_sys->frame.i_samples = a52.i_samples;
p_sys->frame.i_size = a52.i_size;
}
else
p_sys->frame = a52;
p_sys->i_state = STATE_NEXT_SYNC;
case STATE_NEXT_SYNC:
/* Check if next expected frame contains the sync word */
if( block_PeekOffsetBytes( &p_sys->bytestream,
p_sys->frame.i_size, p_header, 2 )
!= VLC_SUCCESS )
{
if( p_block == NULL ) /* drain */
{
p_sys->i_state = STATE_SEND_DATA;
break;
}
/* Need more data */
return NULL;
}
if( p_header[0] == 0 && p_header[1] == 0 )
{
/* A52 wav files and audio CD's use stuffing */
p_sys->i_state = STATE_GET_DATA;
break;
}
if( p_header[0] != 0x0b || p_header[1] != 0x77 )
{
msg_Dbg( p_dec, "emulated sync word "
"(no sync on following frame)" );
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->frame.i_size ) != VLC_SUCCESS )
{
/* Need more data */
return NULL;
}
p_sys->i_state = STATE_SEND_DATA;
case STATE_SEND_DATA:
if( !(p_out_buffer = GetOutBuffer( p_dec )) )
{
//p_dec->b_error = true;
return NULL;
}
/* Copy the whole frame into the buffer. When we reach this point
* we already know we have enough data available. */
block_GetBytes( &p_sys->bytestream, p_out_buffer->p_buffer,
__MIN( p_sys->frame.i_size, p_out_buffer->i_buffer ) );
/* 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 = VLC_TS_INVALID;
if( p_sys->b_discontuinity )
{
p_out_buffer->i_flags |= BLOCK_FLAG_DISCONTINUITY;
p_sys->b_discontuinity = false;
}
/* So p_block doesn't get re-added several times */
if( pp_block )
*pp_block = block_BytestreamPop( &p_sys->bytestream );
p_sys->i_state = STATE_NOSYNC;
return p_out_buffer;
}
}
}