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vlc/include/input_ext-dec.h
Sam Hocevar 08999a39bc * ./src/interface/main.c: we no longer segfault if argc == 0. 
* ALL: renamed PLUGINS to __PLUGINS__ to avoid conflicts with libraries
    defining it. Grmbl.
  * ./src/input/input_ext-plugins.c: cosmetic change.
2002-04-24 00:36:24 +00:00

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/*****************************************************************************
* input_ext-dec.h: structures exported to the VideoLAN decoders
*****************************************************************************
* Copyright (C) 1999-2001 VideoLAN
* $Id: input_ext-dec.h,v 1.56 2002/04/24 00:36:24 sam Exp $
*
* Authors: Christophe Massiot <massiot@via.ecp.fr>
* Michel Kaempf <maxx@via.ecp.fr>
*
* 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., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
*****************************************************************************/
/* ES streams types - see ISO/IEC 13818-1 table 2-29 numbers */
#define MPEG1_VIDEO_ES 0x01
#define MPEG2_VIDEO_ES 0x02
#define MPEG1_AUDIO_ES 0x03
#define MPEG2_AUDIO_ES 0x04
#define AC3_AUDIO_ES 0x81
/* These ones might violate the norm : */
#define DVD_SPU_ES 0x82
#define LPCM_AUDIO_ES 0x83
#define MSMPEG4_VIDEO_ES 0x90
#define MPEG4_VIDEO_ES 0x91
#define UNKNOWN_ES 0xFF
/* Structures exported to the decoders */
/*****************************************************************************
* data_packet_t
*****************************************************************************
* Describe a data packet.
*****************************************************************************/
typedef struct data_packet_s
{
/* Used to chain the packets that carry data for a same PES or PSI */
struct data_packet_s * p_next;
/* start of the PS or TS packet */
byte_t * p_demux_start;
/* start of the PES payload in this packet */
byte_t * p_payload_start;
byte_t * p_payload_end; /* guess ? :-) */
/* is the packet messed up ? */
boolean_t b_discard_payload;
/* pointer to the real data */
struct data_buffer_s * p_buffer;
} data_packet_t;
/*****************************************************************************
* pes_packet_t
*****************************************************************************
* Describes an PES packet, with its properties, and pointers to the TS packets
* containing it.
*****************************************************************************/
typedef struct pes_packet_s
{
/* Chained list to the next PES packet (depending on the context) */
struct pes_packet_s * p_next;
/* PES properties */
boolean_t b_data_alignment; /* used to find the beginning of
* a video or audio unit */
boolean_t b_discontinuity; /* This packet doesn't follow the
* previous one */
mtime_t i_pts; /* PTS for this packet (zero if unset) */
mtime_t i_dts; /* DTS for this packet (zero if unset) */
int i_rate; /* current pace of reading
* (see stream_control.h) */
unsigned int i_pes_size; /* size of the current PES packet */
/* Chained list to packets */
data_packet_t * p_first; /* The first packet contained by this
* PES (used by decoders). */
data_packet_t * p_last; /* The last packet contained by this
PES (used by the buffer allocator) */
unsigned int i_nb_data; /* Number of data packets in the chained
list */
} pes_packet_t;
/*****************************************************************************
* decoder_fifo_t
*****************************************************************************
* This rotative FIFO contains PES packets that are to be decoded.
*****************************************************************************/
typedef struct decoder_fifo_s
{
/* Thread structures */
vlc_mutex_t data_lock; /* fifo data lock */
vlc_cond_t data_wait; /* fifo data conditional variable */
/* Data */
pes_packet_t * p_first;
pes_packet_t ** pp_last;
int i_depth; /* number of PES packets in the stack */
/* Communication interface between input and decoders */
boolean_t b_die; /* the decoder should return now */
boolean_t b_error; /* the decoder is in an error loop */
struct input_buffers_s *p_packets_mgt; /* packets management services
* data */
} decoder_fifo_t;
/*****************************************************************************
* bit_fifo_t : bit fifo descriptor
*****************************************************************************
* This type describes a bit fifo used to store bits while working with the
* input stream at the bit level.
*****************************************************************************/
typedef u32 WORD_TYPE;
typedef struct bit_fifo_s
{
/* This unsigned integer allows us to work at the bit level. This buffer
* can contain 32 bits, and the used space can be found on the MSb's side
* and the available space on the LSb's side. */
WORD_TYPE buffer;
/* Number of bits available in the bit buffer */
int i_available;
} bit_fifo_t;
/*****************************************************************************
* bit_stream_t : bit stream descriptor
*****************************************************************************
* This type, based on a PES stream, includes all the structures needed to
* handle the input stream like a bit stream.
*****************************************************************************/
typedef struct bit_stream_s
{
/*
* Bit structures
*/
bit_fifo_t fifo;
/*
* Input structures
*/
/* The decoder fifo contains the data of the PES stream */
decoder_fifo_t * p_decoder_fifo;
/* Callback to the decoder used when changing data packets ; set
* to NULL if your decoder doesn't need it. */
void (* pf_bitstream_callback)( struct bit_stream_s *,
boolean_t b_new_pes );
/* Optional argument to the callback */
void * p_callback_arg;
/*
* PTS retrieval
*/
mtime_t i_pts, i_dts;
byte_t * p_pts_validity;
/*
* Byte structures
*/
/* Current data packet (in the current PES packet of the PES stream) */
data_packet_t * p_data;
/* Pointer to the next byte that is to be read (in the current packet) */
byte_t * p_byte;
/* Pointer to the last byte that is to be read (in the current packet */
byte_t * p_end;
/* Temporary buffer in case we're not aligned when changing data packets */
WORD_TYPE i_showbits_buffer;
data_packet_t showbits_data;
} bit_stream_t;
/*****************************************************************************
* Inline functions used by the decoders to read bit_stream_t
*****************************************************************************/
/*
* DISCUSSION : How to use the bit_stream structures
*
* sizeof(WORD_TYPE) (usually 32) bits are read at the same time, thus
* minimizing the number of p_byte changes.
* Bits are read via GetBits() or ShowBits.
*
* XXX : Be aware that if, in the forthcoming functions, i_bits > 24,
* the data have to be already aligned on an 8-bit boundary, or wrong
* results will be returned. Use RealignBits() if unsure.
*/
#if (WORD_TYPE == u32)
# define WORD_AT U32_AT
# define WORD_SIGNED s32
#elif (WORD_TYPE == u64)
# define WORD_AT U64_AT
# define WORD_SIGNED s64
#else
# error Unsupported WORD_TYPE
#endif
/*****************************************************************************
* Prototypes from input_ext-dec.c
*****************************************************************************/
#ifndef __PLUGIN__
void InitBitstream ( struct bit_stream_s *, struct decoder_fifo_s *,
void (* pf_bitstream_callback)( struct bit_stream_s *,
boolean_t ),
void * p_callback_arg );
boolean_t NextDataPacket( struct decoder_fifo_s *, struct data_packet_s ** );
void BitstreamNextDataPacket( struct bit_stream_s * );
u32 UnalignedShowBits( struct bit_stream_s *, unsigned int );
void UnalignedRemoveBits( struct bit_stream_s * );
u32 UnalignedGetBits( struct bit_stream_s *, unsigned int );
void CurrentPTS( struct bit_stream_s *, mtime_t *, mtime_t * );
#else
# define InitBitstream p_symbols->InitBitstream
# define NextDataPacket p_symbols->NextDataPacket
# define BitstreamNextDataPacket p_symbols->BitstreamNextDataPacket
# define UnalignedShowBits p_symbols->UnalignedShowBits
# define UnalignedRemoveBits p_symbols->UnalignedRemoveBits
# define UnalignedGetBits p_symbols->UnalignedGetBits
# define CurrentPTS p_symbols->CurrentPTS
#endif
/*****************************************************************************
* AlignWord : fill in the bit buffer so that the byte pointer be aligned
* on a word boundary (XXX: there must be at least sizeof(WORD_TYPE) - 1
* empty bytes in the bit buffer)
*****************************************************************************/
static __inline__ void AlignWord( bit_stream_t * p_bit_stream )
{
while( (ptrdiff_t)p_bit_stream->p_byte
& (sizeof(WORD_TYPE) - 1) )
{
if( p_bit_stream->p_byte < p_bit_stream->p_end )
{
p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
<< (8 * sizeof(WORD_TYPE) - 8
- p_bit_stream->fifo.i_available);
p_bit_stream->fifo.i_available += 8;
}
else
{
BitstreamNextDataPacket( p_bit_stream );
p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
<< (8 * sizeof(WORD_TYPE) - 8
- p_bit_stream->fifo.i_available);
p_bit_stream->fifo.i_available += 8;
}
}
}
/*****************************************************************************
* ShowBits : return i_bits bits from the bit stream
*****************************************************************************/
static __inline__ u32 ShowBits( bit_stream_t * p_bit_stream,
unsigned int i_bits )
{
if( p_bit_stream->fifo.i_available >= i_bits )
{
return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
}
if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
{
return( (p_bit_stream->fifo.buffer |
(WORD_AT( p_bit_stream->p_byte )
>> p_bit_stream->fifo.i_available))
>> (8 * sizeof(WORD_TYPE) - i_bits) );
}
return( UnalignedShowBits( p_bit_stream, i_bits ) );
}
/*****************************************************************************
* ShowSignedBits : return i_bits bits from the bit stream, using signed
* arithmetic
*****************************************************************************/
static __inline__ s32 ShowSignedBits( bit_stream_t * p_bit_stream,
unsigned int i_bits )
{
if( p_bit_stream->fifo.i_available >= i_bits )
{
return( (WORD_SIGNED)p_bit_stream->fifo.buffer
>> (8 * sizeof(WORD_TYPE) - i_bits) );
}
/* You can probably do something a little faster, but now I'm tired. */
return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
>> (32 - i_bits) );
}
/*****************************************************************************
* RemoveBits : removes i_bits bits from the bit buffer
* XXX: do not use for 32 bits, see RemoveBits32
*****************************************************************************/
static __inline__ void RemoveBits( bit_stream_t * p_bit_stream,
unsigned int i_bits )
{
p_bit_stream->fifo.i_available -= i_bits;
if( p_bit_stream->fifo.i_available >= 0 )
{
p_bit_stream->fifo.buffer <<= i_bits;
return;
}
if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
{
p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
<< ( -p_bit_stream->fifo.i_available );
((WORD_TYPE *)p_bit_stream->p_byte)++;
p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
return;
}
UnalignedRemoveBits( p_bit_stream );
}
/*****************************************************************************
* RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
* refill it)
*****************************************************************************/
#if (WORD_TYPE == u32)
static __inline__ void RemoveBits32( bit_stream_t * p_bit_stream )
{
if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
{
if( p_bit_stream->fifo.i_available )
{
p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
<< (32 - p_bit_stream->fifo.i_available);
((WORD_TYPE *)p_bit_stream->p_byte)++;
return;
}
((WORD_TYPE *)p_bit_stream->p_byte)++;
return;
}
p_bit_stream->fifo.i_available -= 32;
UnalignedRemoveBits( p_bit_stream );
}
#else
# define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
#endif
/*****************************************************************************
* GetBits : returns i_bits bits from the bit stream and removes them
* XXX: do not use for 32 bits, see GetBits32
*****************************************************************************/
static __inline__ u32 GetBits( bit_stream_t * p_bit_stream,
unsigned int i_bits )
{
u32 i_result;
p_bit_stream->fifo.i_available -= i_bits;
if( p_bit_stream->fifo.i_available >= 0 )
{
i_result = p_bit_stream->fifo.buffer
>> (8 * sizeof(WORD_TYPE) - i_bits);
p_bit_stream->fifo.buffer <<= i_bits;
return( i_result );
}
if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
{
i_result = p_bit_stream->fifo.buffer
>> (8 * sizeof(WORD_TYPE) - i_bits);
p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
((WORD_TYPE *)p_bit_stream->p_byte)++;
i_result |= p_bit_stream->fifo.buffer
>> (8 * sizeof(WORD_TYPE)
+ p_bit_stream->fifo.i_available);
p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
return( i_result );
}
return UnalignedGetBits( p_bit_stream, i_bits );
}
/*****************************************************************************
* GetSignedBits : returns i_bits bits from the bit stream and removes them,
* using signed arithmetic
* XXX: do not use for 32 bits
*****************************************************************************/
static __inline__ s32 GetSignedBits( bit_stream_t * p_bit_stream,
unsigned int i_bits )
{
if( p_bit_stream->fifo.i_available >= i_bits )
{
s32 i_result;
p_bit_stream->fifo.i_available -= i_bits;
i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
>> (8 * sizeof(WORD_TYPE) - i_bits);
p_bit_stream->fifo.buffer <<= i_bits;
return( i_result );
}
/* You can probably do something a little faster, but now I'm tired. */
return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
>> (32 - i_bits) );
}
/*****************************************************************************
* GetBits32 : returns 32 bits from the bit stream and removes them
*****************************************************************************/
#if (WORD_TYPE == u32)
static __inline__ u32 GetBits32( bit_stream_t * p_bit_stream )
{
u32 i_result;
if( p_bit_stream->fifo.i_available == 32 )
{
p_bit_stream->fifo.i_available = 0;
i_result = p_bit_stream->fifo.buffer;
p_bit_stream->fifo.buffer = 0;
return( i_result );
}
if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
{
if( p_bit_stream->fifo.i_available )
{
i_result = p_bit_stream->fifo.buffer;
p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
((WORD_TYPE *)p_bit_stream->p_byte)++;
i_result |= p_bit_stream->fifo.buffer
>> (p_bit_stream->fifo.i_available);
p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
return( i_result );
}
i_result = WORD_AT( p_bit_stream->p_byte );
((WORD_TYPE *)p_bit_stream->p_byte)++;
return( i_result );
}
p_bit_stream->fifo.i_available -= 32;
return UnalignedGetBits( p_bit_stream, 32 );
}
#else
# define GetBits32( p_bit_stream ) GetBits( p_bit_stream, 32 )
#endif
/*****************************************************************************
* RealignBits : realigns the bit buffer on an 8-bit boundary
*****************************************************************************/
static __inline__ void RealignBits( bit_stream_t * p_bit_stream )
{
p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
p_bit_stream->fifo.i_available &= ~0x7;
}
/*****************************************************************************
* GetChunk : reads a large chunk of data
*****************************************************************************
* The position in the stream must be byte-aligned, if unsure call
* RealignBits(). p_buffer must point to a buffer at least as big as i_buf_len
* otherwise your code will crash.
*****************************************************************************/
static __inline__ void GetChunk( bit_stream_t * p_bit_stream,
byte_t * p_buffer, size_t i_buf_len )
{
ptrdiff_t i_available;
/* We need to take care because i_buf_len may be < 4. */
while( p_bit_stream->fifo.i_available > 0 && i_buf_len )
{
*p_buffer = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - 8);
p_buffer++;
i_buf_len--;
p_bit_stream->fifo.buffer <<= 8;
p_bit_stream->fifo.i_available -= 8;
}
if( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
>= i_buf_len )
{
FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_buf_len );
p_bit_stream->p_byte += i_buf_len;
}
else
{
do
{
FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_available );
p_bit_stream->p_byte = p_bit_stream->p_end;
p_buffer += i_available;
i_buf_len -= i_available;
BitstreamNextDataPacket( p_bit_stream );
}
while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
<= i_buf_len && !p_bit_stream->p_decoder_fifo->b_die );
if( i_buf_len )
{
FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_buf_len );
p_bit_stream->p_byte += i_buf_len;
}
}
if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
{
AlignWord( p_bit_stream );
}
}
/*
* Communication interface between input and decoders
*/
/*****************************************************************************
* decoder_config_t
*****************************************************************************
* Standard pointers given to the decoders as a toolbox.
*****************************************************************************/
typedef struct decoder_config_s
{
u16 i_id;
u8 i_type; /* type of the elementary stream */
void * p_demux_data;
struct stream_ctrl_s * p_stream_ctrl;
struct decoder_fifo_s * p_decoder_fifo;
} decoder_config_t;
/*****************************************************************************
* Prototypes from input_dec.c
*****************************************************************************/
#ifndef __PLUGIN__
void DecoderError ( struct decoder_fifo_s * p_fifo );
#else
# define DecoderError p_symbols->DecoderError
#endif
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