vorbis.c

uclinux 下的vlc播放器源代码

            pi_channels_in = pi_6channels_in;
            break;
        case 4:
            pi_channels_in = pi_4channels_in;
            break;
        case 3:
            pi_channels_in = pi_3channels_in;
            break;
        default:
            {
                int i;
                for( i = 0; i< i_channels; ++i )
                {
                    pi_chan_table[i] = i;
                }
                return;
            }
    }

    if( b_decode )
        aout_CheckChannelReorder( pi_channels_in, pi_channels_out,
                                  i_channel_mask & AOUT_CHAN_PHYSMASK,
                                  i_channels,
                                  pi_chan_table );
    else
        aout_CheckChannelReorder( pi_channels_out, pi_channels_in,
                                  i_channel_mask & AOUT_CHAN_PHYSMASK,
                                  i_channels,
                                  pi_chan_table );
}

/*****************************************************************************
 * Interleave: helper function to interleave channels
 *****************************************************************************/
#ifdef MODULE_NAME_IS_tremor
static void Interleave( int32_t *p_out, const int32_t **pp_in,
                        int i_nb_channels, int i_samples, int *pi_chan_table)
{
    int i, j;

    for ( j = 0; j < i_samples; j++ )
        for ( i = 0; i < i_nb_channels; i++ )
            p_out[j * i_nb_channels + pi_chan_table[i]] = pp_in[i][j] * (FIXED32_ONE >> 24);
}
#else
static void Interleave( float *p_out, const float **pp_in,
                        int i_nb_channels, int i_samples, int *pi_chan_table )
{
    int i, j;

    for ( j = 0; j < i_samples; j++ )
        for ( i = 0; i < i_nb_channels; i++ )
            p_out[j * i_nb_channels + pi_chan_table[i]] = pp_in[i][j];
}
#endif

/*****************************************************************************
 * CloseDecoder: vorbis decoder destruction
 *****************************************************************************/
static void CloseDecoder( vlc_object_t *p_this )
{
    decoder_t *p_dec = (decoder_t *)p_this;
    decoder_sys_t *p_sys = p_dec->p_sys;

    if( !p_sys->b_packetizer && p_sys->i_headers > 3 )
    {
        vorbis_block_clear( &p_sys->vb );
        vorbis_dsp_clear( &p_sys->vd );
    }

    vorbis_comment_clear( &p_sys->vc );
    vorbis_info_clear( &p_sys->vi );  /* must be called last */

    free( p_sys );
}

#if defined(HAVE_VORBIS_VORBISENC_H) && !defined(MODULE_NAME_IS_tremor)

/*****************************************************************************
 * encoder_sys_t : vorbis encoder descriptor
 *****************************************************************************/
struct encoder_sys_t
{
    /*
     * Vorbis properties
     */
    vorbis_info      vi; /* struct that stores all the static vorbis bitstream
                            settings */
    vorbis_comment   vc; /* struct that stores all the bitstream user
                          * comments */
    vorbis_dsp_state vd; /* central working state for the packet->PCM
                          * decoder */
    vorbis_block     vb; /* local working space for packet->PCM decode */

    int i_last_block_size;
    int i_samples_delay;
    int i_channels;

    /*
     * Common properties
     */
    mtime_t i_pts;

    /*
    ** Channel reordering
    */
    int pi_chan_table[AOUT_CHAN_MAX];

};

/*****************************************************************************
 * OpenEncoder: probe the encoder and return score
 *****************************************************************************/
static int OpenEncoder( vlc_object_t *p_this )
{
    encoder_t *p_enc = (encoder_t *)p_this;
    encoder_sys_t *p_sys;
    int i_quality, i_min_bitrate, i_max_bitrate, i;
    ogg_packet header[3];
    vlc_value_t val;
    uint8_t *p_extra;

    if( p_enc->fmt_out.i_codec != VLC_FOURCC('v','o','r','b') &&
        !p_enc->b_force )
    {
        return VLC_EGENERIC;
    }

    /* Allocate the memory needed to store the decoder's structure */
    if( ( p_sys = (encoder_sys_t *)malloc(sizeof(encoder_sys_t)) ) == NULL )
    {
        msg_Err( p_enc, "out of memory" );
        return VLC_EGENERIC;
    }
    p_enc->p_sys = p_sys;

    p_enc->pf_encode_audio = Encode;
    p_enc->fmt_in.i_codec = VLC_FOURCC('f','l','3','2');
    p_enc->fmt_out.i_codec = VLC_FOURCC('v','o','r','b');

    sout_CfgParse( p_enc, ENC_CFG_PREFIX, ppsz_enc_options, p_enc->p_cfg );

    var_Get( p_enc, ENC_CFG_PREFIX "quality", &val );
    i_quality = val.i_int;
    if( i_quality > 10 ) i_quality = 10;
    if( i_quality < 0 ) i_quality = 0;
    var_Get( p_enc, ENC_CFG_PREFIX "cbr", &val );
    if( val.b_bool ) i_quality = 0;
    var_Get( p_enc, ENC_CFG_PREFIX "max-bitrate", &val );
    i_max_bitrate = val.i_int;
    var_Get( p_enc, ENC_CFG_PREFIX "min-bitrate", &val );
    i_min_bitrate = val.i_int;

    /* Initialize vorbis encoder */
    vorbis_info_init( &p_sys->vi );

    if( i_quality > 0 )
    {
        /* VBR mode */
        if( vorbis_encode_setup_vbr( &p_sys->vi,
              p_enc->fmt_in.audio.i_channels, p_enc->fmt_in.audio.i_rate,
              i_quality * 0.1 ) )
        {
            vorbis_info_clear( &p_sys->vi );
            free( p_enc->p_sys );
            msg_Err( p_enc, "VBR mode initialisation failed" );
            return VLC_EGENERIC;
        }

        /* Do we have optional hard quality restrictions? */
        if( i_max_bitrate > 0 || i_min_bitrate > 0 )
        {
            struct ovectl_ratemanage_arg ai;
            vorbis_encode_ctl( &p_sys->vi, OV_ECTL_RATEMANAGE_GET, &ai );

            ai.bitrate_hard_min = i_min_bitrate;
            ai.bitrate_hard_max = i_max_bitrate;
            ai.management_active = 1;

            vorbis_encode_ctl( &p_sys->vi, OV_ECTL_RATEMANAGE_SET, &ai );

        }
        else
        {
            /* Turn off management entirely */
            vorbis_encode_ctl( &p_sys->vi, OV_ECTL_RATEMANAGE_SET, NULL );
        }
    }
    else
    {
        if( vorbis_encode_setup_managed( &p_sys->vi,
              p_enc->fmt_in.audio.i_channels, p_enc->fmt_in.audio.i_rate,
              i_min_bitrate > 0 ? i_min_bitrate * 1000: -1,
              p_enc->fmt_out.i_bitrate,
              i_max_bitrate > 0 ? i_max_bitrate * 1000: -1 ) )
          {
              vorbis_info_clear( &p_sys->vi );
              msg_Err( p_enc, "CBR mode initialisation failed" );
              free( p_enc->p_sys );
              return VLC_EGENERIC;
          }
    }

    vorbis_encode_setup_init( &p_sys->vi );

    /* Add a comment */
    vorbis_comment_init( &p_sys->vc);
    vorbis_comment_add_tag( &p_sys->vc, "ENCODER", "VLC media player");

    /* Set up the analysis state and auxiliary encoding storage */
    vorbis_analysis_init( &p_sys->vd, &p_sys->vi );
    vorbis_block_init( &p_sys->vd, &p_sys->vb );

    /* Create and store headers */
    vorbis_analysis_headerout( &p_sys->vd, &p_sys->vc,
                               &header[0], &header[1], &header[2]);
    p_enc->fmt_out.i_extra = 3 * 2 + header[0].bytes +
       header[1].bytes + header[2].bytes;
    p_extra = p_enc->fmt_out.p_extra = malloc( p_enc->fmt_out.i_extra );
    for( i = 0; i < 3; i++ )
    {
        *(p_extra++) = header[i].bytes >> 8;
        *(p_extra++) = header[i].bytes & 0xFF;
        memcpy( p_extra, header[i].packet, header[i].bytes );
        p_extra += header[i].bytes;
    }

    p_sys->i_channels = p_enc->fmt_in.audio.i_channels;
    p_sys->i_last_block_size = 0;
    p_sys->i_samples_delay = 0;
    p_sys->i_pts = 0;

    ConfigureChannelOrder(p_sys->pi_chan_table, p_sys->vi.channels,
            p_enc->fmt_in.audio.i_physical_channels, VLC_TRUE);

    return VLC_SUCCESS;
}

/****************************************************************************
 * Encode: the whole thing
 ****************************************************************************
 * This function spits out ogg packets.
 ****************************************************************************/
static block_t *Encode( encoder_t *p_enc, aout_buffer_t *p_aout_buf )
{
    encoder_sys_t *p_sys = p_enc->p_sys;
    ogg_packet oggpacket;
    block_t *p_block, *p_chain = NULL;
    float **buffer;
    int i;
    unsigned int j;

    p_sys->i_pts = p_aout_buf->start_date -
                (mtime_t)1000000 * (mtime_t)p_sys->i_samples_delay /
                (mtime_t)p_enc->fmt_in.audio.i_rate;

    p_sys->i_samples_delay += p_aout_buf->i_nb_samples;

    buffer = vorbis_analysis_buffer( &p_sys->vd, p_aout_buf->i_nb_samples );

    /* convert samples to float and uninterleave */
    for( i = 0; i < p_sys->i_channels; i++ )
    {
        for( j = 0 ; j < p_aout_buf->i_nb_samples ; j++ )
        {
            buffer[i][j]= ((float *)p_aout_buf->p_buffer)
                                    [j * p_sys->i_channels + p_sys->pi_chan_table[i]];
        }
    }

    vorbis_analysis_wrote( &p_sys->vd, p_aout_buf->i_nb_samples );

    while( vorbis_analysis_blockout( &p_sys->vd, &p_sys->vb ) == 1 )
    {
        int i_samples;

        vorbis_analysis( &p_sys->vb, NULL );
        vorbis_bitrate_addblock( &p_sys->vb );

        while( vorbis_bitrate_flushpacket( &p_sys->vd, &oggpacket ) )
        {
            int i_block_size;
            p_block = block_New( p_enc, oggpacket.bytes );
            memcpy( p_block->p_buffer, oggpacket.packet, oggpacket.bytes );

            i_block_size = vorbis_packet_blocksize( &p_sys->vi, &oggpacket );

            if( i_block_size < 0 ) i_block_size = 0;
            i_samples = ( p_sys->i_last_block_size + i_block_size ) >> 2;
            p_sys->i_last_block_size = i_block_size;

            p_block->i_length = (mtime_t)1000000 *
                (mtime_t)i_samples / (mtime_t)p_enc->fmt_in.audio.i_rate;

            p_block->i_dts = p_block->i_pts = p_sys->i_pts;

            p_sys->i_samples_delay -= i_samples;

            /* Update pts */
            p_sys->i_pts += p_block->i_length;
            block_ChainAppend( &p_chain, p_block );
        }
    }

    return p_chain;
}

/*****************************************************************************
 * CloseEncoder: vorbis encoder destruction
 *****************************************************************************/
static void CloseEncoder( vlc_object_t *p_this )
{
    encoder_t *p_enc = (encoder_t *)p_this;
    encoder_sys_t *p_sys = p_enc->p_sys;

    vorbis_block_clear( &p_sys->vb );
    vorbis_dsp_clear( &p_sys->vd );
    vorbis_comment_clear( &p_sys->vc );
    vorbis_info_clear( &p_sys->vi );  /* must be called last */

    free( p_sys );
}

#endif /* HAVE_VORBIS_VORBISENC_H && !MODULE_NAME_IS_tremor */