libmp4.c

来自「VLC媒体播放程序」· C语言 代码 · 共 2,060 行 · 第 1/5 页

    return( MP4_SeekStream( p_stream, p_box->i_size + p_box->i_pos ) ? 0 : 1 );
}

/*****************************************************************************
 * For all known box a loader is given,
 *  XXX: all common struct have to be already read by MP4_ReadBoxCommon
 *       after called one of theses functions, file position is unknown
 *       you need to call MP4_GotoBox to go where you want
 *****************************************************************************/
static int MP4_ReadBoxContainerRaw( MP4_Stream_t *p_stream, MP4_Box_t *p_container )
{
    MP4_Box_t *p_box;

    if( MP4_TellStream( p_stream ) + 8 >
                 (off_t)(p_container->i_pos + p_container->i_size) )
    {
        /* there is no box to load */
        return( 0 );
    }

    do
    {
        if( ( p_box = MP4_ReadBox( p_stream, p_container ) ) == NULL )
        {
            break;
        }
        /* chain this box with the father and the other at same level */
        if( !p_container->p_first )
        {
            p_container->p_first = p_box;
        }
        else
        {
            p_container->p_last->p_next = p_box;
        }
        p_container->p_last = p_box;
    } while( MP4_NextBox( p_stream, p_box ) == 1 );

    return( 1 );
}


static int MP4_ReadBoxContainer( MP4_Stream_t *p_stream, MP4_Box_t *p_container )
{
    if( p_container->i_size <= (size_t)MP4_BOX_HEADERSIZE(p_container ) + 8 )
    {
        /* container is empty, 8 stand for the first header in this box */
        return( 1 );
    }

    /* enter box */
    MP4_SeekStream( p_stream, p_container->i_pos + MP4_BOX_HEADERSIZE( p_container ) );

    return( MP4_ReadBoxContainerRaw( p_stream, p_container ) );
}

static void MP4_FreeBox_Common( MP4_Box_t *p_box )
{
    /* Up to now do nothing */
}

static int MP4_ReadBoxSkip( MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    /* XXX sometime moov is hiden in a free box */
    if( p_box->p_father && p_box->p_father->i_type == VLC_FOURCC( 'r', 'o', 'o', 't' )&&
        p_box->i_type == FOURCC_free )
    {
        uint8_t *p_peek;
        int     i_read;
        vlc_fourcc_t i_fcc;

        i_read  = MP4_PeekStream( p_stream, &p_peek, 44 );

        p_peek += MP4_BOX_HEADERSIZE( p_box ) + 4;
        i_read -= MP4_BOX_HEADERSIZE( p_box ) + 4;

        if( i_read >= 8 )
        {
            i_fcc = VLC_FOURCC( p_peek[0], p_peek[1], p_peek[2], p_peek[3] );

            if( i_fcc == FOURCC_cmov || i_fcc == FOURCC_mvhd )
            {
                msg_Warn( p_stream->p_input, "detected moov hidden in a free box ..." );

                p_box->i_type = FOURCC_foov;
                return MP4_ReadBoxContainer( p_stream, p_box );
            }
        }
    }
    /* Nothing to do */
#ifdef MP4_VERBOSE
    msg_Dbg( p_stream->p_input, "skip box: \"%4.4s\"",
            (char*)&p_box->i_type );
#endif
    return( 1 );
}

static int MP4_ReadBox_ftyp( MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    MP4_READBOX_ENTER( MP4_Box_data_ftyp_t );

    MP4_GETFOURCC( p_box->data.p_ftyp->i_major_brand );
    MP4_GET4BYTES( p_box->data.p_ftyp->i_minor_version );

    if( ( p_box->data.p_ftyp->i_compatible_brands_count = i_read / 4 ) )
    {
        unsigned int i;
        p_box->data.p_ftyp->i_compatible_brands =
            calloc( p_box->data.p_ftyp->i_compatible_brands_count, sizeof(uint32_t));

        for( i =0; i < p_box->data.p_ftyp->i_compatible_brands_count; i++ )
        {
            MP4_GETFOURCC( p_box->data.p_ftyp->i_compatible_brands[i] );
        }
    }
    else
    {
        p_box->data.p_ftyp->i_compatible_brands = NULL;
    }

    MP4_READBOX_EXIT( 1 );
}

static void MP4_FreeBox_ftyp( MP4_Box_t *p_box )
{
    FREE( p_box->data.p_ftyp->i_compatible_brands );
}


static int MP4_ReadBox_mvhd(  MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    unsigned int i;
#ifdef MP4_VERBOSE
    char s_creation_time[128];
    char s_modification_time[128];
    char s_duration[128];
#endif
    MP4_READBOX_ENTER( MP4_Box_data_mvhd_t );

    MP4_GETVERSIONFLAGS( p_box->data.p_mvhd );

    if( p_box->data.p_mvhd->i_version )
    {
        MP4_GET8BYTES( p_box->data.p_mvhd->i_creation_time );
        MP4_GET8BYTES( p_box->data.p_mvhd->i_modification_time );
        MP4_GET4BYTES( p_box->data.p_mvhd->i_timescale );
        MP4_GET8BYTES( p_box->data.p_mvhd->i_duration );
    }
    else
    {
        MP4_GET4BYTES( p_box->data.p_mvhd->i_creation_time );
        MP4_GET4BYTES( p_box->data.p_mvhd->i_modification_time );
        MP4_GET4BYTES( p_box->data.p_mvhd->i_timescale );
        MP4_GET4BYTES( p_box->data.p_mvhd->i_duration );
    }
    MP4_GET4BYTES( p_box->data.p_mvhd->i_rate );
    MP4_GET2BYTES( p_box->data.p_mvhd->i_volume );
    MP4_GET2BYTES( p_box->data.p_mvhd->i_reserved1 );


    for( i = 0; i < 2; i++ )
    {
        MP4_GET4BYTES( p_box->data.p_mvhd->i_reserved2[i] );
    }
    for( i = 0; i < 9; i++ )
    {
        MP4_GET4BYTES( p_box->data.p_mvhd->i_matrix[i] );
    }
    for( i = 0; i < 6; i++ )
    {
        MP4_GET4BYTES( p_box->data.p_mvhd->i_predefined[i] );
    }

    MP4_GET4BYTES( p_box->data.p_mvhd->i_next_track_id );


#ifdef MP4_VERBOSE
    MP4_ConvertDate2Str( s_creation_time, p_box->data.p_mvhd->i_creation_time );
    MP4_ConvertDate2Str( s_modification_time,
                         p_box->data.p_mvhd->i_modification_time );
    if( p_box->data.p_mvhd->i_rate )
    {
        MP4_ConvertDate2Str( s_duration,
                 p_box->data.p_mvhd->i_duration / p_box->data.p_mvhd->i_rate );
    }
    else
    {
        s_duration[0] = 0;
    }
    msg_Dbg( p_stream->p_input, "read box: \"mvhd\" creation %s modification %s time scale %d duration %s rate %f volume %f next track id %d",
                  s_creation_time,
                  s_modification_time,
                  (uint32_t)p_box->data.p_mvhd->i_timescale,
                  s_duration,
                  (float)p_box->data.p_mvhd->i_rate / (1<<16 ),
                  (float)p_box->data.p_mvhd->i_volume / 256 ,
                  (uint32_t)p_box->data.p_mvhd->i_next_track_id );
#endif
    MP4_READBOX_EXIT( 1 );
}

static int MP4_ReadBox_tkhd(  MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    unsigned int i;
#ifdef MP4_VERBOSE
    char s_creation_time[128];
    char s_modification_time[128];
    char s_duration[128];
#endif
    MP4_READBOX_ENTER( MP4_Box_data_tkhd_t );

    MP4_GETVERSIONFLAGS( p_box->data.p_tkhd );

    if( p_box->data.p_tkhd->i_version )
    {
        MP4_GET8BYTES( p_box->data.p_tkhd->i_creation_time );
        MP4_GET8BYTES( p_box->data.p_tkhd->i_modification_time );
        MP4_GET4BYTES( p_box->data.p_tkhd->i_track_ID );
        MP4_GET4BYTES( p_box->data.p_tkhd->i_reserved );
        MP4_GET8BYTES( p_box->data.p_tkhd->i_duration );
    }
    else
    {
        MP4_GET4BYTES( p_box->data.p_tkhd->i_creation_time );
        MP4_GET4BYTES( p_box->data.p_tkhd->i_modification_time );
        MP4_GET4BYTES( p_box->data.p_tkhd->i_track_ID );
        MP4_GET4BYTES( p_box->data.p_tkhd->i_reserved );
        MP4_GET4BYTES( p_box->data.p_tkhd->i_duration );
    }

    for( i = 0; i < 2; i++ )
    {
        MP4_GET4BYTES( p_box->data.p_tkhd->i_reserved2[i] );
    }
    MP4_GET2BYTES( p_box->data.p_tkhd->i_layer );
    MP4_GET2BYTES( p_box->data.p_tkhd->i_predefined );
    MP4_GET2BYTES( p_box->data.p_tkhd->i_volume );
    MP4_GET2BYTES( p_box->data.p_tkhd->i_reserved3 );

    for( i = 0; i < 9; i++ )
    {
        MP4_GET4BYTES( p_box->data.p_tkhd->i_matrix[i] );
    }
    MP4_GET4BYTES( p_box->data.p_tkhd->i_width );
    MP4_GET4BYTES( p_box->data.p_tkhd->i_height );

#ifdef MP4_VERBOSE
    MP4_ConvertDate2Str( s_creation_time, p_box->data.p_mvhd->i_creation_time );
    MP4_ConvertDate2Str( s_modification_time, p_box->data.p_mvhd->i_modification_time );
    MP4_ConvertDate2Str( s_duration, p_box->data.p_mvhd->i_duration );

    msg_Dbg( p_stream->p_input, "read box: \"tkhd\" creation %s modification %s duration %s track ID %d layer %d volume %f width %f height %f",
                  s_creation_time,
                  s_modification_time,
                  s_duration,
                  p_box->data.p_tkhd->i_track_ID,
                  p_box->data.p_tkhd->i_layer,
                  (float)p_box->data.p_tkhd->i_volume / 256 ,
                  (float)p_box->data.p_tkhd->i_width / 65536,
                  (float)p_box->data.p_tkhd->i_height / 65536 );
#endif
    MP4_READBOX_EXIT( 1 );
}


static int MP4_ReadBox_mdhd( MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    unsigned int i;
    uint16_t i_language;
#ifdef MP4_VERBOSE
    char s_creation_time[128];
    char s_modification_time[128];
    char s_duration[128];
#endif
    MP4_READBOX_ENTER( MP4_Box_data_mdhd_t );

    MP4_GETVERSIONFLAGS( p_box->data.p_mdhd );

    if( p_box->data.p_mdhd->i_version )
    {
        MP4_GET8BYTES( p_box->data.p_mdhd->i_creation_time );
        MP4_GET8BYTES( p_box->data.p_mdhd->i_modification_time );
        MP4_GET4BYTES( p_box->data.p_mdhd->i_timescale );
        MP4_GET8BYTES( p_box->data.p_mdhd->i_duration );
    }
    else
    {
        MP4_GET4BYTES( p_box->data.p_mdhd->i_creation_time );
        MP4_GET4BYTES( p_box->data.p_mdhd->i_modification_time );
        MP4_GET4BYTES( p_box->data.p_mdhd->i_timescale );
        MP4_GET4BYTES( p_box->data.p_mdhd->i_duration );
    }
    i_language = GetWBE( p_peek );
    for( i = 0; i < 3; i++ )
    {
        p_box->data.p_mdhd->i_language[i] =
                    ( ( i_language >> ( (2-i)*5 ) )&0x1f ) + 0x60;
    }

    MP4_GET2BYTES( p_box->data.p_mdhd->i_predefined );

#ifdef MP4_VERBOSE
    MP4_ConvertDate2Str( s_creation_time, p_box->data.p_mdhd->i_creation_time );
    MP4_ConvertDate2Str( s_modification_time, p_box->data.p_mdhd->i_modification_time );
    MP4_ConvertDate2Str( s_duration, p_box->data.p_mdhd->i_duration );
    msg_Dbg( p_stream->p_input, "read box: \"mdhd\" creation %s modification %s time scale %d duration %s language %c%c%c",
                  s_creation_time,
                  s_modification_time,
                  (uint32_t)p_box->data.p_mdhd->i_timescale,
                  s_duration,
                  p_box->data.p_mdhd->i_language[0],
                  p_box->data.p_mdhd->i_language[1],
                  p_box->data.p_mdhd->i_language[2] );
#endif
    MP4_READBOX_EXIT( 1 );
}


static int MP4_ReadBox_hdlr( MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    MP4_READBOX_ENTER( MP4_Box_data_hdlr_t );

    MP4_GETVERSIONFLAGS( p_box->data.p_hdlr );

    MP4_GET4BYTES( p_box->data.p_hdlr->i_predefined );
    MP4_GETFOURCC( p_box->data.p_hdlr->i_handler_type );

    p_box->data.p_hdlr->psz_name = calloc( sizeof( char ), i_read + 1 );
    memcpy( p_box->data.p_hdlr->psz_name, p_peek, i_read );

#ifdef MP4_VERBOSE
    msg_Dbg( p_stream->p_input, "read box: \"hdlr\" hanler type %4.4s name %s",
                       (char*)&p_box->data.p_hdlr->i_handler_type,
                       p_box->data.p_hdlr->psz_name );

#endif
    MP4_READBOX_EXIT( 1 );
}

static void MP4_FreeBox_hdlr( MP4_Box_t *p_box )
{
    FREE( p_box->data.p_hdlr->psz_name );
}

static int MP4_ReadBox_vmhd( MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    unsigned int i;

    MP4_READBOX_ENTER( MP4_Box_data_vmhd_t );

    MP4_GETVERSIONFLAGS( p_box->data.p_vmhd );

    MP4_GET2BYTES( p_box->data.p_vmhd->i_graphics_mode );
    for( i = 0; i < 3; i++ )
    {
        MP4_GET2BYTES( p_box->data.p_vmhd->i_opcolor[i] );
    }

#ifdef MP4_VERBOSE
    msg_Dbg( p_stream->p_input, "read box: \"vmhd\" graphics-mode %d opcolor (%d, %d, %d)",
                      p_box->data.p_vmhd->i_graphics_mode,
                      p_box->data.p_vmhd->i_opcolor[0],
                      p_box->data.p_vmhd->i_opcolor[1],
                      p_box->data.p_vmhd->i_opcolor[2] );
#endif
    MP4_READBOX_EXIT( 1 );
}

static int MP4_ReadBox_smhd( MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    MP4_READBOX_ENTER( MP4_Box_data_smhd_t );

    MP4_GETVERSIONFLAGS( p_box->data.p_smhd );



    MP4_GET2BYTES( p_box->data.p_smhd->i_balance );

    MP4_GET2BYTES( p_box->data.p_smhd->i_reserved );

#ifdef MP4_VERBOSE
    msg_Dbg( p_stream->p_input, "read box: \"smhd\" balance %f",
                      (float)p_box->data.p_smhd->i_balance / 256 );
#endif
    MP4_READBOX_EXIT( 1 );
}


static int MP4_ReadBox_hmhd( MP4_Stream_t *p_stream, MP4_Box_t *p_box )
{
    MP4_READBOX_ENTER( MP4_Box_data_hmhd_t );

    MP4_GETVERSIONFLAGS( p_box->data.p_hmhd );

    MP4_GET2BYTES( p_box->data.p_hmhd->i_max_PDU_size );
    MP4_GET2BYTES( p_box->data.p_hmhd->i_avg_PDU_size );

    MP4_GET4BYTES( p_box->data.p_hmhd->i_max_bitrate );
    MP4_GET4BYTES( p_box->data.p_hmhd->i_avg_bitrate );

    MP4_GET4BYTES( p_box->data.p_hmhd->i_reserved );

#ifdef MP4_VERBOSE
    msg_Dbg( p_stream->p_input, "read box: \"hmhd\" maxPDU-size %d avgPDU-size %d max-bitrate %d avg-bitrate %d",
                      p_box->data.p_hmhd->i_max_PDU_size,
                      p_box->data.p_hmhd->i_avg_PDU_size,
                      p_box->data.p_hmhd->i_max_bitrate,
                      p_box->data.p_hmhd->i_avg_bitrate );
#endif
    MP4_READBOX_EXIT( 1 );
}