Skip to content

V
vlc-2-2
Commit 933abd7b authored by Laurent Aimar's avatar Laurent Aimar
Browse files
Options

Split out a52 parsing functions into a52.h

parent 2479ed41
Show whitespace changes
Inline Side-by-side
Showing with 250 additions and 195 deletions
modules/codec/a52.c
View file @ 933abd7b
......@@ -35,7 +35,8 @@
#include <vlc_codec.h>
#include <vlc_aout.h>
#include <vlc_block_helper.h>
#include <vlc_bits.h>
#include "a52.h"
/*****************************************************************************
* Module descriptor
......@@ -61,8 +62,6 @@ vlc_module_end ()
* decoder_sys_t : decoder descriptor
*****************************************************************************/
#define A52_HEADER_SIZE 7
struct decoder_sys_t
{
/* Module mode */
......@@ -81,8 +80,8 @@ struct decoder_sys_t
audio_date_t end_date;
mtime_t i_pts;
int i_frame_size, i_bit_rate;
unsigned int i_rate, i_channels, i_channels_conf;
vlc_a52_header_t frame;
};
enum {
......@@ -100,9 +99,6 @@ enum {
****************************************************************************/
static void *DecodeBlock ( decoder_t *, block_t ** );
static int SyncInfo ( const uint8_t *, unsigned int *, unsigned int *,
unsigned int *, int * );
static uint8_t *GetOutBuffer ( decoder_t *, void ** );
static aout_buffer_t *GetAoutBuffer( decoder_t * );
static block_t *GetSoutBuffer( decoder_t * );
......@@ -179,7 +175,7 @@ static int OpenPacketizer( vlc_object_t *p_this )
static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
{
decoder_sys_t *p_sys = p_dec->p_sys;
uint8_t p_header[A52_HEADER_SIZE];
uint8_t p_header[VLC_A52_HEADER_SIZE];
uint8_t *p_buf;
void *p_out_buffer;
......@@ -240,27 +236,23 @@ static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
p_sys->i_state = STATE_HEADER;
case STATE_HEADER:
/* Get A/52 frame header (A52_HEADER_SIZE bytes) */
/* Get A/52 frame header (VLC_A52_HEADER_SIZE bytes) */
if( block_PeekBytes( &p_sys->bytestream, p_header,
A52_HEADER_SIZE ) != VLC_SUCCESS )
VLC_A52_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->i_channels,
&p_sys->i_channels_conf,
&p_sys->i_rate,
&p_sys->i_bit_rate );
if( !p_sys->i_frame_size )
if( vlc_a52_header_Parse( &p_sys->frame, 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;
}
p_sys->i_state = STATE_NEXT_SYNC;
case STATE_NEXT_SYNC:
......@@ -269,7 +261,7 @@ static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
/* Check if next expected frame contains the sync word */
if( block_PeekOffsetBytes( &p_sys->bytestream,
p_sys->i_frame_size, p_header, 2 )
p_sys->frame.i_size, p_header, 2 )
!= VLC_SUCCESS )
{
/* Need more data */
......@@ -299,7 +291,7 @@ static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
/* 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 )
p_sys->frame.i_size ) != VLC_SUCCESS )
{
/* Need more data */
return NULL;
......@@ -315,7 +307,7 @@ static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
/* 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, p_sys->i_frame_size );
block_GetBytes( &p_sys->bytestream, p_buf, p_sys->frame.i_size );
/* Make sure we don't reuse the same pts twice */
if( p_sys->i_pts == p_sys->bytestream.p_block->i_pts )
......@@ -354,26 +346,26 @@ static uint8_t *GetOutBuffer( decoder_t *p_dec, void **pp_out_buffer )
decoder_sys_t *p_sys = p_dec->p_sys;
uint8_t *p_buf;
if( p_dec->fmt_out.audio.i_rate != p_sys->i_rate )
if( p_dec->fmt_out.audio.i_rate != p_sys->frame.i_rate )
{
msg_Info( p_dec, "A/52 channels:%d samplerate:%d bitrate:%d",
p_sys->i_channels, p_sys->i_rate, p_sys->i_bit_rate );
p_sys->frame.i_channels, p_sys->frame.i_rate, p_sys->frame.i_bitrate );
aout_DateInit( &p_sys->end_date, p_sys->i_rate );
aout_DateInit( &p_sys->end_date, p_sys->frame.i_rate );
aout_DateSet( &p_sys->end_date, p_sys->i_pts );
}
p_dec->fmt_out.audio.i_rate = p_sys->i_rate;
p_dec->fmt_out.audio.i_channels = p_sys->i_channels;
if( p_dec->fmt_out.audio.i_bytes_per_frame < p_sys->i_frame_size )
p_dec->fmt_out.audio.i_bytes_per_frame = p_sys->i_frame_size;
p_dec->fmt_out.audio.i_rate = p_sys->frame.i_rate;
p_dec->fmt_out.audio.i_channels = p_sys->frame.i_channels;
if( p_dec->fmt_out.audio.i_bytes_per_frame < p_sys->frame.i_size )
p_dec->fmt_out.audio.i_bytes_per_frame = p_sys->frame.i_size;
p_dec->fmt_out.audio.i_frame_length = A52_FRAME_NB;
p_dec->fmt_out.audio.i_original_channels = p_sys->i_channels_conf;
p_dec->fmt_out.audio.i_original_channels = p_sys->frame.i_channels_conf;
p_dec->fmt_out.audio.i_physical_channels =
p_sys->i_channels_conf & AOUT_CHAN_PHYSMASK;
p_sys->frame.i_channels_conf & AOUT_CHAN_PHYSMASK;
p_dec->fmt_out.i_bitrate = p_sys->i_bit_rate;
p_dec->fmt_out.i_bitrate = p_sys->frame.i_bitrate;
if( p_sys->b_packetizer )
{
......@@ -416,7 +408,7 @@ static block_t *GetSoutBuffer( decoder_t *p_dec )
decoder_sys_t *p_sys = p_dec->p_sys;
block_t *p_block;
p_block = block_New( p_dec, p_sys->i_frame_size );
p_block = block_New( p_dec, p_sys->frame.i_size );
if( p_block == NULL ) return NULL;
p_block->i_pts = p_block->i_dts = aout_DateGet( &p_sys->end_date );
......@@ -427,167 +419,3 @@ static block_t *GetSoutBuffer( decoder_t *p_dec )
return p_block;
}
/* Tables */
static const struct
{
unsigned int i_count;
unsigned int i_configuration;
} p_acmod[8] = {
{ 2, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_DUALMONO }, /* Dual-channel 1+1 */
{ 1, AOUT_CHAN_CENTER }, /* Mono 1/0 */
{ 2, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT }, /* Stereo 2/0 */
{ 3, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER }, /* 3F 3/0 */
{ 3, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_REARCENTER }, /* 2F1R 2/1 */
{ 4, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
AOUT_CHAN_REARCENTER }, /* 3F1R 3/1 */
{ 5, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT }, /* 2F2R 2/2 */
{ 6, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT }, /* 3F2R 3/2 */
};
/**
* It parse AC3 sync info.
*
* This code is borrowed from liba52 by Aaron Holtzman & Michel Lespinasse,
* since we don't want to oblige S/PDIF people to use liba52 just to get
* their SyncInfo...
*/
static int SyncInfoAC3( const uint8_t *p_buf,
unsigned int *pi_channels,
unsigned int *pi_channels_conf,
unsigned int *pi_sample_rate, int *pi_bit_rate )
{
static const uint8_t halfrate[12] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3 };
static const int rate[] = { 32, 40, 48, 56, 64, 80, 96, 112,
128, 160, 192, 224, 256, 320, 384, 448,
512, 576, 640 };
static const uint8_t lfeon[8] = { 0x10, 0x10, 0x04, 0x04,
0x04, 0x01, 0x04, 0x01 };
int frmsizecod;
int bitrate;
int half;
int acmod;
/* */
half = halfrate[p_buf[5] >> 3];
/* acmod, dsurmod and lfeon */
acmod = p_buf[6] >> 5;
if ( (p_buf[6] & 0xf8) == 0x50 )
{
/* Dolby surround = stereo + Dolby */
*pi_channels = 2;
*pi_channels_conf = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
| AOUT_CHAN_DOLBYSTEREO;
}
else
{
*pi_channels = p_acmod[acmod].i_count;
*pi_channels_conf = p_acmod[acmod].i_configuration;
}
if ( p_buf[6] & lfeon[acmod] )
{
(*pi_channels)++;
*pi_channels_conf |= AOUT_CHAN_LFE;
}
frmsizecod = p_buf[4] & 63;
if (frmsizecod >= 38)
return 0;
bitrate = rate [frmsizecod >> 1];
*pi_bit_rate = (bitrate * 1000) >> half;
switch (p_buf[4] & 0xc0) {
case 0:
*pi_sample_rate = 48000 >> half;
return 4 * bitrate;
case 0x40:
*pi_sample_rate = 44100 >> half;
return 2 * (320 * bitrate / 147 + (frmsizecod & 1));
case 0x80:
*pi_sample_rate = 32000 >> half;
return 6 * bitrate;
default:
return 0;
}
}
/**
* It parse E-AC3 sync info
*/
static int SyncInfoEAC3( const uint8_t *p_buf,
unsigned int *pi_channels,
unsigned int *pi_channels_conf,
unsigned int *pi_sample_rate, int *pi_bit_rate )
{
static const int pi_samplerate[3] = { 48000, 44100, 32000 };
bs_t s;
int i_frame_size;
int i_fscod, i_fscod2;
int i_numblkscod;
int i_acmod, i_lfeon;
int i_bytes;
bs_init( &s, (void*)p_buf, A52_HEADER_SIZE );
bs_skip( &s, 16 + /* start code */
2 + /* stream type */
3 ); /* substream id */
i_frame_size = bs_read( &s, 11 );
if( i_frame_size < 2 )
return 0;
i_bytes = 2 * ( i_frame_size + 1 );
i_fscod = bs_read( &s, 2 );
if( i_fscod == 0x03 )
{
i_fscod2 = bs_read( &s, 2 );
if( i_fscod2 == 0X03 )
return 0;
*pi_sample_rate = pi_samplerate[i_fscod2] / 2;
i_numblkscod = 6;
}
else
{
static const int pi_blocks[4] = { 1, 2, 3, 6 };
*pi_sample_rate = pi_samplerate[i_fscod];
i_numblkscod = pi_blocks[bs_read( &s, 2 )];
}
i_acmod = bs_read( &s, 3 );
i_lfeon = bs_read1( &s );
*pi_channels = p_acmod[i_acmod].i_count + i_lfeon;
*pi_channels_conf = p_acmod[i_acmod].i_configuration | ( i_lfeon ? AOUT_CHAN_LFE : 0);
*pi_bit_rate = 8 * i_bytes * (*pi_sample_rate) / (i_numblkscod * 256);
return i_bytes;
}
static int SyncInfo( const uint8_t *p_buf,
unsigned int *pi_channels,
unsigned int *pi_channels_conf,
unsigned int *pi_sample_rate, int *pi_bit_rate )
{
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 SyncInfoAC3( p_buf, pi_channels, pi_channels_conf,
pi_sample_rate, pi_bit_rate );
else
return SyncInfoEAC3( p_buf, pi_channels, pi_channels_conf,
pi_sample_rate, pi_bit_rate );
}
modules/codec/a52.h 0 → 100644
View file @ 933abd7b
/*****************************************************************************
* a52.h
*****************************************************************************
* Copyright (C) 2001-2009 Laurent Aimar
* $Id$
*
* Authors: Stéphane Borel <stef@via.ecp.fr>
* Christophe Massiot <massiot@via.ecp.fr>
* Gildas Bazin <gbazin@videolan.org>
* Laurent Aimar <fenrir@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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
#ifndef _VLC_A52_H
#define _VLC_A52_H 1
#include <vlc_aout.h>
#include <vlc_bits.h>
typedef struct
{
unsigned int i_count;
unsigned int i_configuration;
} vlc_a52_acmod_t;
/**
* Minimum AC3 header size that vlc_a52_header_Parse needs.
*/
#define VLC_A52_HEADER_SIZE (8)
/**
* AC3 header information.
*/
typedef struct
{
bool b_eac3;
unsigned int i_channels;
unsigned int i_channels_conf;
unsigned int i_rate;
unsigned int i_bitrate;
unsigned int i_size;
} vlc_a52_header_t;
/**
* It parse AC3 sync info.
*
* This code is borrowed from liba52 by Aaron Holtzman & Michel Lespinasse,
* since we don't want to oblige S/PDIF people to use liba52 just to get
* their SyncInfo...
*/
static inline int vlc_a52_header_ParseAc3( vlc_a52_header_t *p_header,
const uint8_t *p_buf,
const vlc_a52_acmod_t *p_acmod )
{
static const uint8_t pi_halfrate[12] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3 };
static const unsigned int pi_bitrate[] = { 32, 40, 48, 56, 64, 80, 96, 112,
128, 160, 192, 224, 256, 320, 384, 448,
512, 576, 640 };
static const uint8_t pi_lfeon[8] = { 0x10, 0x10, 0x04, 0x04,
0x04, 0x01, 0x04, 0x01 };
/* */
const unsigned i_rate_shift = pi_halfrate[p_buf[5] >> 3];
/* acmod, dsurmod and lfeon */
const unsigned i_acmod = p_buf[6] >> 5;
if( (p_buf[6] & 0xf8) == 0x50 )
{
/* Dolby surround = stereo + Dolby */
p_header->i_channels = 2;
p_header->i_channels_conf = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
| AOUT_CHAN_DOLBYSTEREO;
}
else
{
p_header->i_channels = p_acmod[i_acmod].i_count;
p_header->i_channels_conf = p_acmod[i_acmod].i_configuration;
}
if( p_buf[6] & pi_lfeon[i_acmod] )
{
p_header->i_channels++;
p_header->i_channels_conf |= AOUT_CHAN_LFE;
}
const unsigned i_frmsizecod = p_buf[4] & 63;
if( i_frmsizecod >= 38 )
return VLC_EGENERIC;
const unsigned i_bitrate_base = pi_bitrate[i_frmsizecod >> 1];
p_header->i_bitrate = (i_bitrate_base * 1000) >> i_rate_shift;
switch( p_buf[4] & 0xc0 )
{
case 0:
p_header->i_rate = 48000 >> i_rate_shift;
p_header->i_size = 4 * i_bitrate_base;
break;
case 0x40:
p_header->i_rate = 44100 >> i_rate_shift;
p_header->i_size = 2 * (320 * i_bitrate_base / 147 + (i_frmsizecod & 1));
break;
case 0x80:
p_header->i_rate = 32000 >> i_rate_shift;
p_header->i_size = 6 * i_bitrate_base;
break;
default:
return VLC_EGENERIC;
}
p_header->b_eac3 = false;
return VLC_SUCCESS;
}
/**
* It parse E-AC3 sync info
*/
static inline int vlc_a52_header_ParseEac3( vlc_a52_header_t *p_header,
const uint8_t *p_buf,
const vlc_a52_acmod_t *p_acmod )
{
static const unsigned pi_samplerate[3] = { 48000, 44100, 32000 };
unsigned i_numblkscod;
bs_t s;
bs_init( &s, (void*)p_buf, VLC_A52_HEADER_SIZE );
bs_skip( &s, 16 + /* start code */
2 + /* stream type */
3 ); /* substream id */
const unsigned i_frame_size = bs_read( &s, 11 );
if( i_frame_size < 2 )
return VLC_EGENERIC;
p_header->i_size = 2 * ( i_frame_size + 1 );
const unsigned i_fscod = bs_read( &s, 2 );
if( i_fscod == 0x03 )
{
const unsigned i_fscod2 = bs_read( &s, 2 );
if( i_fscod2 == 0X03 )
return VLC_EGENERIC;
p_header->i_rate = pi_samplerate[i_fscod2] / 2;
i_numblkscod = 6;
}
else
{
static const int pi_blocks[4] = { 1, 2, 3, 6 };
p_header->i_rate = pi_samplerate[i_fscod];
i_numblkscod = pi_blocks[bs_read( &s, 2 )];
}
const unsigned i_acmod = bs_read( &s, 3 );
const unsigned i_lfeon = bs_read1( &s );
p_header->i_channels = p_acmod[i_acmod].i_count + i_lfeon;
p_header->i_channels_conf = p_acmod[i_acmod].i_configuration | ( i_lfeon ? AOUT_CHAN_LFE : 0);
p_header->i_bitrate = 8 * p_header->i_size * (p_header->i_rate) / (i_numblkscod * 256);
p_header->b_eac3 = true;
return VLC_SUCCESS;
}
/**
* It will parse the header AC3 frame and fill vlc_a52_header_t* if
* it is valid or return VLC_EGENERIC.
*
* XXX It will only recognize big endian bitstream ie starting with 0x0b, 0x77
*/
static inline int vlc_a52_header_Parse( vlc_a52_header_t *p_header,
const uint8_t *p_buffer, int i_buffer )
{
static const vlc_a52_acmod_t p_acmod[8] = {
{ 2, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_DUALMONO }, /* Dual-channel 1+1 */
{ 1, AOUT_CHAN_CENTER }, /* Mono 1/0 */
{ 2, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT }, /* Stereo 2/0 */
{ 3, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER }, /* 3F 3/0 */
{ 3, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_REARCENTER }, /* 2F1R 2/1 */
{ 4, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
AOUT_CHAN_REARCENTER }, /* 3F1R 3/1 */
{ 5, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT }, /* 2F2R 2/2 */
{ 6, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT }, /* 3F2R 3/2 */
};
if( i_buffer < VLC_A52_HEADER_SIZE )
return VLC_EGENERIC;
/* Check synword */
if( p_buffer[0] != 0x0b || p_buffer[1] != 0x77 )
return VLC_EGENERIC;
/* Check bsid */
const int bsid = p_buffer[5] >> 3;
if( bsid > 16 )
return VLC_EGENERIC;
if( bsid <= 10 )
{
if( vlc_a52_header_ParseAc3( p_header, p_buffer, p_acmod ) )
return VLC_EGENERIC;
}
else
{
if( vlc_a52_header_ParseEac3( p_header, p_buffer, p_acmod ) )
return VLC_EGENERIC;
}
return VLC_SUCCESS;
}
#endif
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment