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/*****************************************************************************
* cc.h
*****************************************************************************
* Copyright (C) 2007 Laurent Aimar
* $Id$
*
* Authors: 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 Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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 _CC_H
#define _CC_H 1
#include <vlc_bits.h>
#define BLOCK_FLAG_ORDERED_CAPTIONS (0x01 << BLOCK_FLAG_PRIVATE_SHIFT)
/* CC have a maximum rate of 9600 bit/s (per field?) */
#define CC_MAX_DATA_SIZE (2 * 3*600)
enum
{
CC_PAYLOAD_NONE,
CC_PAYLOAD_GA94,
CC_PAYLOAD_DVD,
CC_PAYLOAD_REPLAYTV,
CC_PAYLOAD_SCTE20,
};
typedef struct
{
/* Which channel are present */
bool pb_present[4];
/* */
bool b_reorder;
/* */
int i_payload_type;
int i_payload_other_count;
/* CC data per field
* byte[x+0]: field (0/1)
* byte[x+1]: cc data 1
* byte[x+2]: cc data 2
*/
int i_data;
uint8_t p_data[CC_MAX_DATA_SIZE];
} cc_data_t;
static inline void cc_Init( cc_data_t *c )
{
int i;
for( i = 0; i < 4; i++ )
c-> pb_present[i] = false;
c->i_data = 0;
c->b_reorder = false;
c->i_payload_type = CC_PAYLOAD_NONE;
c->i_payload_other_count = 0;
}
static inline void cc_Exit( cc_data_t *c )
{
VLC_UNUSED(c);
return;
}
static inline void cc_Flush( cc_data_t *c )
{
c->i_data = 0;
}
static inline void cc_AppendData( cc_data_t *c, int i_field, const uint8_t cc[2] )
{
if( i_field == 0 || i_field == 1 )
{
c->pb_present[2*i_field+0] =
c->pb_present[2*i_field+1] = true;
}
c->p_data[c->i_data++] = i_field;
c->p_data[c->i_data++] = cc[0];
c->p_data[c->i_data++] = cc[1];
}
static inline void cc_Extract( cc_data_t *c, bool b_top_field_first, const uint8_t *p_src, int i_src )
{
static const uint8_t p_cc_ga94[4] = { 0x47, 0x41, 0x39, 0x34 };
static const uint8_t p_cc_dvd[4] = { 0x43, 0x43, 0x01, 0xf8 };
static const uint8_t p_cc_replaytv4a[2] = { 0xbb, 0x02 };
static const uint8_t p_cc_replaytv4b[2] = { 0xcc, 0x02 };
static const uint8_t p_cc_replaytv5a[2] = { 0x99, 0x02 };
static const uint8_t p_cc_replaytv5b[2] = { 0xaa, 0x02 };
static const uint8_t p_cc_scte20[2] = { 0x03, 0x81 };
static const uint8_t p_cc_scte20_old[2] = { 0x03, 0x01 };
if( i_src < 4 )
return;
int i_payload_type;
if( !memcmp( p_cc_ga94, p_src, 4 ) && i_src >= 5+1+1+1 && p_src[4] == 0x03 )
{
/* CC from DVB/ATSC TS */
i_payload_type = CC_PAYLOAD_GA94;
}
else if( !memcmp( p_cc_dvd, p_src, 4 ) && i_src > 4+1 )
{
i_payload_type = CC_PAYLOAD_DVD;
}
else if( i_src >= 2+2 + 2+2 &&
( ( !memcmp( p_cc_replaytv4a, &p_src[0], 2 ) && !memcmp( p_cc_replaytv4b, &p_src[4], 2 ) ) ||
( !memcmp( p_cc_replaytv5a, &p_src[0], 2 ) && !memcmp( p_cc_replaytv5b, &p_src[4], 2 ) ) ) )
{
i_payload_type = CC_PAYLOAD_REPLAYTV;
}
else if( ( !memcmp( p_cc_scte20, p_src, 2 ) ||
!memcmp( p_cc_scte20_old, p_src, 2 ) ) && i_src > 2 )
{
i_payload_type = CC_PAYLOAD_SCTE20;
}
else
{
#if 0
#define V(x) ( ( x < 0x20 || x >= 0x7f ) ? '?' : x )
fprintf( stderr, "-------------- unknown user data " );
for( int i = 0; i < i_src; i++ )
fprintf( stderr, "%2.2x ", p_src[i] );
for( int i = 0; i < i_src; i++ )
fprintf( stderr, "%c ", V(p_src[i]) );
fprintf( stderr, "\n" );
#undef V
#endif
return;
}
if( c->i_payload_type != CC_PAYLOAD_NONE && c->i_payload_type != i_payload_type )
{
c->i_payload_other_count++;
if( c->i_payload_other_count < 50 )
return;
}
c->i_payload_type = i_payload_type;
c->i_payload_other_count = 0;
if( i_payload_type == CC_PAYLOAD_GA94 )
{
/* cc_data()
* u1 reserved(1)
* u1 process_cc_data_flag
* u1 additional_data_flag
* u5 cc_count
* u8 reserved(1111 1111)
* for cc_count
* u5 marker bit(1111 1)
* u1 cc_valid
* u2 cc_type
* u8 cc_data_1
* u8 cc_data_2
* u8 marker bit(1111 1111)
* if additional_data_flag
* unknown
*/
/* cc_type:
* 0x00: field 1
* 0x01: field 2
*/
const uint8_t *cc = &p_src[5];
const int i_count_cc = cc[0]&0x1f;
int i;
if( !(cc[0]&0x40) ) // process flag
return;
if( i_src < 5 + 1+1 + i_count_cc*3 + 1) // broken packet
return;
if( i_count_cc <= 0 ) // no cc present
return;
if( cc[2+i_count_cc * 3] != 0xff ) // marker absent
return;
cc += 2;
for( i = 0; i < i_count_cc; i++, cc += 3 )
{
int i_field = cc[0] & 0x03;
if( ( cc[0] & 0xfc ) != 0xfc )
continue;
if( i_field != 0 && i_field != 1 )
continue;
if( c->i_data + 3 > CC_MAX_DATA_SIZE )
continue;
cc_AppendData( c, i_field, &cc[1] );
}
c->b_reorder = true;
}
else if( i_payload_type == CC_PAYLOAD_DVD )
{
const int b_truncate = p_src[4] & 0x01;
const int i_field_first = (p_src[4] & 0x80) ? 0 : 1;
const int i_count_cc2 = (p_src[4] >> 1) & 0xf;
const uint8_t *cc = &p_src[5];
int i;
if( i_src < 4+1+6*i_count_cc2 - ( b_truncate ? 3 : 0) )
return;
for( i = 0; i < i_count_cc2; i++ )
{
int j;
for( j = 0; j < 2; j++, cc += 3 )
{
const int i_field = j == i_field_first ? 0 : 1;
if( b_truncate && i == i_count_cc2 - 1 && j == 1 )
break;
if( cc[0] != 0xff && cc[0] != 0xfe )
continue;
if( c->i_data + 3 > CC_MAX_DATA_SIZE )
continue;
cc_AppendData( c, i_field, &cc[1] );
}
}
c->b_reorder = false;
}
else if( i_payload_type == CC_PAYLOAD_REPLAYTV )
{
const uint8_t *cc = &p_src[0];
int i;
if( c->i_data + 2*3 > CC_MAX_DATA_SIZE )
return;
for( i = 0; i < 2; i++, cc += 4 )
{
const int i_field = i == 0 ? 1 : 0;
cc_AppendData( c, i_field, &cc[2] );
}
c->b_reorder = false;
}
else
{
bs_t s;
bs_init( &s, &p_src[2], i_src - 2 );
const int i_cc_count = bs_read( &s, 5 );
for( int i = 0; i < i_cc_count; i++ )
{
bs_skip( &s, 2 );
const int i_field_idx = bs_read( &s, 2 );
bs_skip( &s, 5 );
uint8_t cc[2];
for( int j = 0; j < 2; j++ )
{
cc[j] = 0;
for( int k = 0; k < 8; k++ )
cc[j] |= bs_read( &s, 1 ) << k;
}
bs_skip( &s, 1 );
if( i_field_idx == 0 )
continue;
if( c->i_data + 2*3 > CC_MAX_DATA_SIZE )
continue;
/* 1,2,3 -> 0,1,0. I.E. repeated field 3 is merged with field 1 */
int i_field = ((i_field_idx - 1) & 1);
if (!b_top_field_first)
i_field ^= 1;
cc_AppendData( c, i_field, &cc[0] );
}
c->b_reorder = true;
}
}
#endif /* _CC_H */