ps.h

VLC Player Source Code

/*****************************************************************************
 * ps.h: Program Stream demuxer helper
 *****************************************************************************
 * Copyright (C) 2004 the VideoLAN team
 * $Id$
 *
 * Authors: Laurent Aimar <[e-mail]>
 *
 * 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.
 *****************************************************************************/

#include <vlc_demux.h>

/* 256-0xC0 for normal stream, 256 for 0xbd stream, 256 for 0xfd stream */
#define PS_TK_COUNT (768 - 0xc0)
#define PS_ID_TO_TK( id ) ((id) <= 0xff ? (id) - 0xc0 : \
            ((id)&0xff) + (((id)&0xff00) == 0xbd00 ? 256-0xC0 : 512-0xc0) )

typedef struct ps_psm_t ps_psm_t;
static inline int ps_id_to_type( const ps_psm_t *, int );
static inline const uint8_t *ps_id_to_lang( const ps_psm_t *, int );

typedef struct
{
    bool  b_seen;
    int         i_skip;
    int         i_id;
    es_out_id_t *es;
    es_format_t fmt;
    mtime_t     i_first_pts;
    mtime_t     i_last_pts;

} ps_track_t;

/* Init a set of track */
static inline void ps_track_init( ps_track_t tk[PS_TK_COUNT] )
{
    int i;
    for( i = 0; i < PS_TK_COUNT; i++ )
    {
        tk[i].b_seen = false;
        tk[i].i_skip = 0;
        tk[i].i_id   = 0;
        tk[i].es     = NULL;
        tk[i].i_first_pts = -1;
        tk[i].i_last_pts = -1;
        es_format_Init( &tk[i].fmt, UNKNOWN_ES, 0 );
    }
}

/* From id fill i_skip and es_format_t */
static inline int ps_track_fill( ps_track_t *tk, ps_psm_t *p_psm, int i_id )
{
    tk->i_skip = 0;
    tk->i_id = i_id;
    if( ( i_id&0xff00 ) == 0xbd00 )
    {
        if( ( i_id&0xf8 ) == 0x88 || (i_id&0xf8) == 0x98 )
        {
            es_format_Init( &tk->fmt, AUDIO_ES, VLC_FOURCC('d','t','s',' ') );
            tk->i_skip = 4;
        }
        else if( ( i_id&0xf0 ) == 0x80
               ||  (i_id&0xf0) == 0xc0 ) /* AC-3, Can also be used for DD+/E-AC-3 */
        {
            es_format_Init( &tk->fmt, AUDIO_ES, VLC_FOURCC('a','5','2',' ') );
            tk->i_skip = 4;
        }
        else if( (i_id&0xf0) == 0xb0 )
        {
            es_format_Init( &tk->fmt, AUDIO_ES, VLC_FOURCC('m','l','p',' ') );
            /* FIXME / untested ... no known decoder (at least not in VLC/ffmpeg) */
        }
        else if( ( i_id&0xe0 ) == 0x20 )
        {
            es_format_Init( &tk->fmt, SPU_ES, VLC_FOURCC('s','p','u',' ') );
            tk->i_skip = 1;
        }
        else if( ( i_id&0xf0 ) == 0xa0 )
        {
            es_format_Init( &tk->fmt, AUDIO_ES, VLC_FOURCC('l','p','c','m') );
            tk->i_skip = 1;
        }
        else if( ( i_id&0xff ) == 0x70 )
        {
            es_format_Init( &tk->fmt, SPU_ES, VLC_FOURCC('o','g','t',' ') );
        }
        else if( ( i_id&0xfc ) == 0x00 )
        {
            es_format_Init( &tk->fmt, SPU_ES, VLC_FOURCC('c','v','d',' ') );
        }
        else if( ( i_id&0xff ) == 0x10 )
        {
            es_format_Init( &tk->fmt, SPU_ES, VLC_FOURCC('t','e','l','x') );
        }
        else
        {
            es_format_Init( &tk->fmt, UNKNOWN_ES, 0 );
            return VLC_EGENERIC;
        }
    }
    else if( (i_id&0xff00) == 0xfd00 )
    {
        uint8_t i_sub_id = i_id & 0xff;
        if( i_sub_id >= 0x55 && i_sub_id <= 0x5f )
        {
            es_format_Init( &tk->fmt, VIDEO_ES, VLC_FOURCC('W','V','C','1') );
        }
        else
        {
            es_format_Init( &tk->fmt, UNKNOWN_ES, 0 );
            return VLC_EGENERIC;
        }
    }
    else
    {
        int i_type = ps_id_to_type( p_psm , i_id );

        es_format_Init( &tk->fmt, UNKNOWN_ES, 0 );

        if( (i_id&0xf0) == 0xe0 && i_type == 0x1b )
        {
            es_format_Init( &tk->fmt, VIDEO_ES, VLC_FOURCC('h','2','6','4') );
        }
        else if( (i_id&0xf0) == 0xe0 && i_type == 0x10 )
        {
            es_format_Init( &tk->fmt, VIDEO_ES, VLC_FOURCC('m','p','4','v') );
        }
        else if( (i_id&0xf0) == 0xe0 && i_type == 0x02 )
        {
            es_format_Init( &tk->fmt, VIDEO_ES, VLC_FOURCC('m','p','g','v') );
        }
        else if( ( i_id&0xe0 ) == 0xc0 && i_type == 0x0f )
        {
            es_format_Init( &tk->fmt, AUDIO_ES, VLC_FOURCC('m','p','4','a') );
        }
        else if( ( i_id&0xe0 ) == 0xc0 && i_type == 0x03 )
        {
            es_format_Init( &tk->fmt, AUDIO_ES, VLC_FOURCC('m','p','g','a') );
        }

        if( tk->fmt.i_cat == UNKNOWN_ES && ( i_id&0xf0 ) == 0xe0 )
        {
            es_format_Init( &tk->fmt, VIDEO_ES, VLC_FOURCC('m','p','g','v') );
        }
        else if( tk->fmt.i_cat == UNKNOWN_ES && ( i_id&0xe0 ) == 0xc0 )
        {
            es_format_Init( &tk->fmt, AUDIO_ES, VLC_FOURCC('m','p','g','a') );
        }
        else if( tk->fmt.i_cat == UNKNOWN_ES ) return VLC_EGENERIC;
    }

    /* PES packets usually contain truncated frames */
    tk->fmt.b_packetized = false;

    if( ps_id_to_lang( p_psm, i_id ) )
    {
        tk->fmt.psz_language = malloc( 4 );
        if( tk->fmt.psz_language )
        {
            memcpy( tk->fmt.psz_language, ps_id_to_lang( p_psm , i_id ), 3 );
            tk->fmt.psz_language[3] = 0;
        }
    }

    return VLC_SUCCESS;
}

/* return the id of a PES (should be valid) */
static inline int ps_pkt_id( block_t *p_pkt )
{
    if( p_pkt->p_buffer[3] == 0xbd &&
        p_pkt->i_buffer >= 9 &&
        p_pkt->i_buffer >= 9 + (size_t)p_pkt->p_buffer[8] )
    {
        /* VOB extension */
        return 0xbd00 | p_pkt->p_buffer[9+p_pkt->p_buffer[8]];
    }
    else if( p_pkt->p_buffer[3] == 0xfd &&
             p_pkt->i_buffer >= 9 &&
             (p_pkt->p_buffer[6]&0xC0) == 0x80 &&   /* mpeg2 */
             (p_pkt->p_buffer[7]&0x01) == 0x01 )    /* extension_flag */
    {
        /* ISO 13818 amendment 2 and SMPTE RP 227 */
        const uint8_t i_flags = p_pkt->p_buffer[7];
        unsigned int i_skip = 9;

        /* Find PES extension */
        if( (i_flags & 0x80 ) )
        {
            i_skip += 5;        /* pts */
            if( (i_flags & 0x40) )
                i_skip += 5;    /* dts */
        }
        if( (i_flags & 0x20 ) )
            i_skip += 6;
        if( (i_flags & 0x10 ) )
            i_skip += 3;
        if( (i_flags & 0x08 ) )
            i_skip += 1;
        if( (i_flags & 0x04 ) )
            i_skip += 1;
        if( (i_flags & 0x02 ) )
            i_skip += 2;

        if( i_skip < p_pkt->i_buffer && (p_pkt->p_buffer[i_skip]&0x01) )
        {
            const uint8_t i_flags2 = p_pkt->p_buffer[i_skip];

            /* Find PES extension 2 */
            i_skip += 1;
            if( i_flags2 & 0x80 )
                i_skip += 16;
            if( (i_flags2 & 0x40) && i_skip < p_pkt->i_buffer )
                i_skip += 1 + p_pkt->p_buffer[i_skip];
            if( i_flags2 & 0x20 )
                i_skip += 2;
            if( i_flags2 & 0x10 )
                i_skip += 2;

            if( i_skip + 1 < p_pkt->i_buffer )
            {
                const int i_extension_field_length = p_pkt->p_buffer[i_skip]&0x7f;
                if( i_extension_field_length >=1 )
                {
                    int i_stream_id_extension_flag = (p_pkt->p_buffer[i_skip+1] >> 7)&0x1;
                    if( i_stream_id_extension_flag == 0 )
                        return 0xfd00 | (p_pkt->p_buffer[i_skip+1]&0x7f);
                }
            }
        }
    }
    return p_pkt->p_buffer[3];
}

/* return the size of the next packet
 * XXX you need to give him at least 14 bytes (and it need to start as a
 * valid packet) */
static inline int ps_pkt_size( const uint8_t *p, int i_peek )
{
    if( p[3] == 0xb9 && i_peek >= 4 )
    {
        return 4;
    }
    else if( p[3] == 0xba )
    {
        if( (p[4] >> 6) == 0x01 && i_peek >= 14 )
        {
            return 14 + (p[13]&0x07);
        }
        else if( (p[4] >> 4) == 0x02 && i_peek >= 12 )
        {
            return 12;
        }
        return -1;
    }
    else if( i_peek >= 6 )
    {
        return 6 + ((p[4]<<8) | p[5] );
    }
    return -1;
}

/* parse a PACK PES */
static inline int ps_pkt_parse_pack( block_t *p_pkt, int64_t *pi_scr,
                                     int *pi_mux_rate )
{
    uint8_t *p = p_pkt->p_buffer;
    if( p_pkt->i_buffer >= 14 && (p[4] >> 6) == 0x01 )
    {
        *pi_scr =((((int64_t)p[4]&0x38) << 27 )|
                  (((int64_t)p[4]&0x03) << 28 )|
                   ((int64_t)p[5] << 20 )|
                  (((int64_t)p[6]&0xf8) << 12 )|
                  (((int64_t)p[6]&0x03) << 13 )|
                   ((int64_t)p[7] << 5 )|
                   ((int64_t)p[8] >> 3 )) * 100 / 9;

        *pi_mux_rate = ( p[10] << 14 )|( p[11] << 6 )|( p[12] >> 2);
    }
    else if( p_pkt->i_buffer >= 12 && (p[4] >> 4) == 0x02 )
    {
        *pi_scr =((((int64_t)p[4]&0x0e) << 29 )|
                   ((int64_t)p[5] << 22 )|
                  (((int64_t)p[6]&0xfe) << 14 )|
                   ((int64_t)p[7] <<  7 )|
                   ((int64_t)p[8] >> 1 )) * 100 / 9;

        *pi_mux_rate = ( ( p[9]&0x7f )<< 15 )|( p[10] << 7 )|( p[11] >> 1);
    }
    else
    {
        return VLC_EGENERIC;
    }
    return VLC_SUCCESS;
}

/* Parse a SYSTEM PES */
static inline int ps_pkt_parse_system( block_t *p_pkt, ps_psm_t *p_psm,
                                       ps_track_t tk[PS_TK_COUNT] )