ad_twin.c

自己移植的linux下的流媒体播放器原代码,支持mms协议,支持ftp和http协议.

            nbits, BITS_INT);
        exit(1);
    }
    retval = bread(tmpbit, sizeof(*tmpbit), nbits, sh);
    for (ibit=retval; ibit<nbits; ibit++){
        tmpbit[ibit] = 0;
    }
    mask = 0x1<<(nbits-1);
    work=0;
    for ( ibit=0; ibit<nbits; ibit++ ){
        work += mask*tmpbit[ibit];
        mask >>= 1;
    }
    *data = work;
    return(retval);
}

static int GetVqInfo( tvqConfInfoSubBlock *cfg,
            int bits0[],
            int bits1[],
            int variableBits,
            INDEX *index,
            sh_audio_t *sh)
{
    int idiv;
    int bitcount = 0;

    if ( index->btype == BLK_LONG ){
        TvqUpdateVectorInfo( variableBits, &cfg->ndiv, bits0, bits1 ); // re-calculate VQ bits
    }
    for ( idiv=0; idiv<cfg->ndiv; idiv++ ){
        bitcount += get_bstm(&index->wvq[idiv],bits0[idiv],sh); /* CB 0 */
        bitcount += get_bstm(&index->wvq[idiv+cfg->ndiv],bits1[idiv],sh); /* CB 1 */
    }
    return bitcount;
}

static int GetBseInfo( tvqConfInfo *cf, tvqConfInfoSubBlock *cfg, INDEX *index, sh_audio_t *sh)
{
    int i_sup, isf, itmp, idiv;
    int bitcount = 0;

    for ( i_sup=0; i_sup<cf->N_CH; i_sup++ ){
        for ( isf=0; isf<cfg->nsf; isf++ ){
            for ( idiv=0; idiv<cfg->fw_ndiv; idiv++ ){
                itmp = idiv + ( isf + i_sup * cfg->nsf ) * cfg->fw_ndiv;
                bitcount += get_bstm(&index->fw[itmp],cfg->fw_nbit,sh);
            }
        }
    }
    for ( i_sup=0; i_sup<cf->N_CH; i_sup++ ){
        for ( isf=0; isf<cfg->nsf; isf++ ){
            bitcount += get_bstm(&index->fw_alf[i_sup * cfg->nsf + isf],cf->FW_ARSW_BITS,sh);
        }
    }
    return bitcount;
}

static int GetGainInfo(tvqConfInfo *cf, tvqConfInfoSubBlock *cfg, INDEX *index, sh_audio_t *sh )
{
    int i_sup, iptop, isf;
    int bitcount = 0;

    for ( i_sup=0; i_sup<cf->N_CH; i_sup++ ){
        iptop = ( cfg->nsubg + 1 ) * i_sup;
        bitcount += get_bstm(&index->pow[iptop], cf->GAIN_BITS,sh);
        for ( isf=0; isf<cfg->nsubg; isf++ ){
            bitcount += get_bstm(&index->pow[iptop+isf+1], cf->SUB_GAIN_BITS,sh);
        }
    }
    return bitcount;
}

static int GetLspInfo( tvqConfInfo *cf, INDEX *index, sh_audio_t *sh )
{
    int i_sup, itmp;
    int bitcount = 0;

    for ( i_sup=0; i_sup<cf->N_CH; i_sup++ ){
        bitcount += get_bstm(&index->lsp[i_sup][0], cf->LSP_BIT0,sh); /* pred. switch */
        bitcount += get_bstm(&index->lsp[i_sup][1], cf->LSP_BIT1,sh); /* first stage */
        for ( itmp=0; itmp<cf->LSP_SPLIT; itmp++ ){         /* second stage */
            bitcount += get_bstm(&index->lsp[i_sup][itmp+2], cf->LSP_BIT2,sh);
        }
    }

    return bitcount;
}

static int GetPpcInfo( tvqConfInfo *cf, INDEX *index, sh_audio_t *sh)
{
    int idiv, i_sup;
    int bitcount = 0;
    vqf_priv_t*priv=sh->context;
    
    for ( idiv=0; idiv<cf->N_DIV_P; idiv++ ){
        bitcount += get_bstm(&(index->pls[idiv]), priv->bits_0[BLK_PPC][idiv],sh);       /*CB0*/
        bitcount += get_bstm(&(index->pls[idiv+cf->N_DIV_P]), priv->bits_1[BLK_PPC][idiv],sh);/*CB1*/
    }
    for (i_sup=0; i_sup<cf->N_CH; i_sup++){
        bitcount += get_bstm(&(index->pit[i_sup]), cf->BASF_BIT,sh);
        bitcount += get_bstm(&(index->pgain[i_sup]), cf->PGAIN_BIT,sh);
    }
    
    return bitcount;
}

static int GetEbcInfo( tvqConfInfo *cf, tvqConfInfoSubBlock *cfg, INDEX *index, sh_audio_t *sh)
{
    int i_sup, isf, itmp;
    int bitcount = 0;

    for ( i_sup=0; i_sup<cf->N_CH; i_sup++ ){
        for ( isf=0; isf<cfg->nsf; isf++){
            int indexSfOffset = isf * ( cfg->ncrb - cfg->ebc_crb_base ) - cfg->ebc_crb_base;
            for ( itmp=cfg->ebc_crb_base; itmp<cfg->ncrb; itmp++ ){
                bitcount += get_bstm(&index->bc[i_sup][itmp+indexSfOffset], cfg->ebc_bits,sh);
            }
        }
    }
    
    return bitcount;
}

static int vqf_read_frame(sh_audio_t *sh,INDEX *index)
{
    /*--- Variables ---*/
    tvqConfInfoSubBlock *cfg;
    int variableBits;
    int bitcount;
    int numFixedBitsPerFrame = TvqGetNumFixedBitsPerFrame();
    int btype;
    vqf_priv_t *priv=sh->context;
    
    /*--- Initialization ---*/
    variableBits = 0;
    bitcount = 0;

    /*--- read block independent factors ---*/
    /* Window type */
    bitcount += get_bstm( &index->w_type, priv->cf.BITS_WTYPE, sh );
    if ( TvqWtypeToBtype( index->w_type, &index->btype ) ) {
        mp_msg(MSGT_DECAUDIO, MSGL_ERR, "Error: unknown window type: %d\n", index->w_type);
        return 0;
    }
    btype = index->btype;

    /*--- read block dependent factors ---*/
    cfg = &priv->cf.cfg[btype]; // set the block dependent paremeters table

    bitcount += variableBits;
    
    /* Interleaved vector quantization */
    bitcount += GetVqInfo( cfg, priv->bits_0[btype], priv->bits_1[btype], variableBits, index, sh );
    
    /* Bark-scale envelope */
    bitcount += GetBseInfo( &priv->cf, cfg, index, sh );
    /* Gain */
    bitcount += GetGainInfo( &priv->cf, cfg, index, sh );
    /* LSP */
    bitcount += GetLspInfo( &priv->cf, index, sh );
    /* PPC */
    if ( cfg->ppc_enable ){
        bitcount += GetPpcInfo( &priv->cf, index, sh );
    }
    /* Energy Balance Calibration */
    if ( cfg->ebc_enable ){
        bitcount += GetEbcInfo( &priv->cf, cfg, index, sh );
    }
    
    return bitcount == numFixedBitsPerFrame ? bitcount/8 : 0;
}

static void frtobuf_s16(float out[],       /* Input  --- input data frame */
        short bufout[],    /* Output --- output data buffer array */
        unsigned frameSize,   /* Input  --- frame size */
        unsigned numChannels) /* Input  --- number of channels */
{
    /*--- Variables ---*/
    unsigned ismp, ich;
    float *ptr;
    float dtmp;
    
    for ( ich=0; ich<numChannels; ich++ ){
        ptr = out+ich*frameSize;
        for ( ismp=0; ismp<frameSize; ismp++ ){
            dtmp = ptr[ismp];
            if ( dtmp >= 0. ) {
                if ( dtmp > 32700. )
                dtmp = 32700.;
                bufout[ismp*numChannels+ich] = (short)(dtmp+0.5);
            } else {
                if ( dtmp < -32700. )
                dtmp = -32700.;
                bufout[ismp*numChannels+ich] = (short)(dtmp-0.5);
            }
        }
    }
}

static void frtobuf_float(float out[],       /* Input  --- input data frame */
        float bufout[],    /* Output --- output data buffer array */
        unsigned frameSize,   /* Input  --- frame size */
        unsigned numChannels) /* Input  --- number of channels */
{
    /*--- Variables ---*/
    unsigned ismp, ich;
    float *ptr;
    float dtmp;
    
    for ( ich=0; ich<numChannels; ich++ ){
        ptr = out+ich*frameSize;
        for ( ismp=0; ismp<frameSize; ismp++ ){
            dtmp = ptr[ismp];
            if ( dtmp >= 0. ) {
                if ( dtmp > 32700. )
                dtmp = 32700.;
                bufout[ismp*numChannels+ich] = dtmp/32767.;
            } else {
                if ( dtmp < -32700. )
                dtmp = -32700.;
                bufout[ismp*numChannels+ich] = dtmp/32767.;
            }
        }
    }
}

int decode_audio(sh_audio_t *sh_audio,unsigned char *buf,int minlen,int maxlen)
{
    int l, len=0;
    vqf_priv_t *priv=sh_audio->context;
    while(len<minlen)
    {
        float out[priv->framesize*sh_audio->channels];
        l=vqf_read_frame(sh_audio,&priv->index);
        if(!l) break;
        TvqDecodeFrame(&priv->index, out);
        if (priv->skip_cnt) {
            // Ingnore first two frames, replace them with silence
            priv->skip_cnt--;
            memset(buf, 0, priv->framesize*sh_audio->channels*sh_audio->samplesize);
        } else {
           if (sh_audio->sample_format == AF_FORMAT_S16_NE)
               frtobuf_s16(out, (short *)buf, priv->framesize, sh_audio->channels);
           else
               frtobuf_float(out, (float *)buf, priv->framesize, sh_audio->channels);
        }
        len += priv->framesize*sh_audio->channels*sh_audio->samplesize;
        buf += priv->framesize*sh_audio->channels*sh_audio->samplesize;
    }
    return len;
}

#endif