vorbis.c

tcpmp播放器的flv插件

        
        if (init_vlc(&codebook_setup->vlc, codebook_setup->nb_bits, entries, tmp_vlc_bits, sizeof(*tmp_vlc_bits), sizeof(*tmp_vlc_bits), tmp_vlc_codes, sizeof(*tmp_vlc_codes), sizeof(*tmp_vlc_codes), INIT_VLC_LE)) {
            av_log(vc->avccontext, AV_LOG_ERROR, " Error generating vlc tables. \n");
            goto error;
        }
    }

    av_free(tmp_vlc_bits);
    av_free(tmp_vlc_codes);
    return 0;

// Error:
error:
    av_free(tmp_vlc_bits);
    av_free(tmp_vlc_codes);
    return 1;
}

// Process time domain transforms part (unused in Vorbis I)

static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc) {
    GetBitContext *gb=&vc->gb;
    uint_fast8_t i;
    uint_fast8_t vorbis_time_count=get_bits(gb, 6)+1;

    for(i=0;i<vorbis_time_count;++i) {
        uint_fast16_t vorbis_tdtransform=get_bits(gb, 16);

        AV_DEBUG(" Vorbis time domain transform %d: %d \n", vorbis_time_count, vorbis_tdtransform);

        if (vorbis_tdtransform) {
            av_log(vc->avccontext, AV_LOG_ERROR, "Vorbis time domain transform data nonzero. \n");
            return 1;
        }
    }
    return 0;
}

// Process floors part - only floor type 1 is supported

static int vorbis_parse_setup_hdr_floors(vorbis_context *vc) {
    GetBitContext *gb=&vc->gb;
    uint_fast16_t i,j,k;

    vc->floor_count=get_bits(gb, 6)+1;

    vc->floors=(vorbis_floor *)av_mallocz(vc->floor_count * sizeof(vorbis_floor));

    for (i=0;i<vc->floor_count;++i) {
        vorbis_floor *floor_setup=&vc->floors[i];

        floor_setup->floor_type=get_bits(gb, 16);

        AV_DEBUG(" %d. floor type %d \n", i, floor_setup->floor_type);

        if (floor_setup->floor_type==1) {
            uint_fast8_t maximum_class=0;
            uint_fast8_t rangebits;
            uint_fast16_t floor1_values=2;

            floor_setup->partitions=get_bits(gb, 5);

            AV_DEBUG(" %d.floor: %d partitions \n", i, floor_setup->partitions);

            for(j=0;j<floor_setup->partitions;++j) {
                floor_setup->partition_class[j]=get_bits(gb, 4);
                if (floor_setup->partition_class[j]>maximum_class) maximum_class=floor_setup->partition_class[j];

                AV_DEBUG(" %d. floor %d partition class %d \n", i, j, floor_setup->partition_class[j]);

            }

            AV_DEBUG(" maximum class %d \n", maximum_class);

            floor_setup->maximum_class=maximum_class;

            for(j=0;j<=maximum_class;++j) {
                floor_setup->class_dimensions[j]=get_bits(gb, 3)+1;
                floor_setup->class_subclasses[j]=get_bits(gb, 2);

                AV_DEBUG(" %d floor %d class dim: %d subclasses %d \n", i, j, floor_setup->class_dimensions[j], floor_setup->class_subclasses[j]);

                if (floor_setup->class_subclasses[j]) {
                    floor_setup->class_masterbook[j]=get_bits(gb, 8);

                    AV_DEBUG("   masterbook: %d \n", floor_setup->class_masterbook[j]);
                }

                for(k=0;k<(1<<floor_setup->class_subclasses[j]);++k) {
                    floor_setup->subclass_books[j][k]=get_bits(gb, 8)-1;

                    AV_DEBUG("    book %d. : %d \n", k, floor_setup->subclass_books[j][k]);
                }
            }

            floor_setup->multiplier=get_bits(gb, 2)+1;
            floor_setup->x_list_dim=2;

            for(j=0;j<floor_setup->partitions;++j) {
                floor_setup->x_list_dim+=floor_setup->class_dimensions[floor_setup->partition_class[j]];
            }

            floor_setup->x_list=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
            floor_setup->x_list_order=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
            floor_setup->low_neighbour=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
            floor_setup->high_neighbour=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));


            rangebits=get_bits(gb, 4);
            floor_setup->x_list[0] = 0;
            floor_setup->x_list[1] = (1<<rangebits);

            for(j=0;j<floor_setup->partitions;++j) {
                for(k=0;k<floor_setup->class_dimensions[floor_setup->partition_class[j]];++k,++floor1_values) {
                    floor_setup->x_list[floor1_values]=get_bits(gb, rangebits);

                    AV_DEBUG(" %d. floor1 Y coord. %d \n", floor1_values, floor_setup->x_list[floor1_values]);
                }
            }

// Precalculate order of x coordinates - needed for decode

            for(k=0;k<floor_setup->x_list_dim;++k) {
                floor_setup->x_list_order[k]=k;
            }

            for(k=0;k<floor_setup->x_list_dim-1;++k) {   // FIXME optimize sorting ?
                for(j=k+1;j<floor_setup->x_list_dim;++j) {
                    if(floor_setup->x_list[floor_setup->x_list_order[k]]>floor_setup->x_list[floor_setup->x_list_order[j]]) {
                        uint_fast16_t tmp=floor_setup->x_list_order[k];
                        floor_setup->x_list_order[k]=floor_setup->x_list_order[j];
                        floor_setup->x_list_order[j]=tmp;
                    }
                }
            }

// Precalculate low and high neighbours

            for(k=2;k<floor_setup->x_list_dim;++k) {
                floor_setup->low_neighbour[k]=0;
                floor_setup->high_neighbour[k]=1;  // correct according to SPEC requirements

                for (j=0;j<k;++j) {
                    if ((floor_setup->x_list[j]<floor_setup->x_list[k]) &&
                      (floor_setup->x_list[j]>floor_setup->x_list[floor_setup->low_neighbour[k]])) {
                        floor_setup->low_neighbour[k]=j;
                    }
                    if ((floor_setup->x_list[j]>floor_setup->x_list[k]) &&
                      (floor_setup->x_list[j]<floor_setup->x_list[floor_setup->high_neighbour[k]])) {
                        floor_setup->high_neighbour[k]=j;
                    }
                }
            }
        }
        else {
            av_log(vc->avccontext, AV_LOG_ERROR, "Only floor type 1 supported. \n");
            return 1;
        }
    }
    return 0;
}

// Process residues part

static int vorbis_parse_setup_hdr_residues(vorbis_context *vc){
    GetBitContext *gb=&vc->gb;
    uint_fast8_t i, j, k;

    vc->residue_count=get_bits(gb, 6)+1;
    vc->residues=(vorbis_residue *)av_mallocz(vc->residue_count * sizeof(vorbis_residue));

    AV_DEBUG(" There are %d residues. \n", vc->residue_count);

    for(i=0;i<vc->residue_count;++i) {
        vorbis_residue *res_setup=&vc->residues[i];
        uint_fast8_t cascade[64];
        uint_fast8_t high_bits;
        uint_fast8_t low_bits;

        res_setup->type=get_bits(gb, 16);

        AV_DEBUG(" %d. residue type %d \n", i, res_setup->type);

        res_setup->begin=get_bits(gb, 24);
        res_setup->end=get_bits(gb, 24);
        res_setup->partition_size=get_bits(gb, 24)+1;
        res_setup->classifications=get_bits(gb, 6)+1;
        res_setup->classbook=get_bits(gb, 8);

        AV_DEBUG("    begin %d end %d part.size %d classif.s %d classbook %d \n", res_setup->begin, res_setup->end, res_setup->partition_size,
          res_setup->classifications, res_setup->classbook);

        for(j=0;j<res_setup->classifications;++j) {
            high_bits=0;
            low_bits=get_bits(gb, 3);
            if (get_bits1(gb)) {
                high_bits=get_bits(gb, 5);
            }
            cascade[j]=(high_bits<<3)+low_bits;

            AV_DEBUG("     %d class casscade depth: %d \n", j, ilog(cascade[j]));
        }

        res_setup->maxpass=0;
        for(j=0;j<res_setup->classifications;++j) {
            for(k=0;k<8;++k) {
                if (cascade[j]&(1<<k)) {
                        res_setup->books[j][k]=get_bits(gb, 8);

                    AV_DEBUG("     %d class casscade depth %d book: %d \n", j, k, res_setup->books[j][k]);

                    if (k>res_setup->maxpass) {
                        res_setup->maxpass=k;
                    }
                } else {
                    res_setup->books[j][k]=-1;
                }
            }
        }
    }
    return 0;
}

// Process mappings part

static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc) {
    GetBitContext *gb=&vc->gb;
    uint_fast8_t i, j;

    vc->mapping_count=get_bits(gb, 6)+1;
    vc->mappings=(vorbis_mapping *)av_mallocz(vc->mapping_count * sizeof(vorbis_mapping));

    AV_DEBUG(" There are %d mappings. \n", vc->mapping_count);

    for(i=0;i<vc->mapping_count;++i) {
        vorbis_mapping *mapping_setup=&vc->mappings[i];

        if (get_bits(gb, 16)) {
            av_log(vc->avccontext, AV_LOG_ERROR, "Other mappings than type 0 are not compliant with the Vorbis I specification. \n");
            return 1;
        }
        if (get_bits1(gb)) {
            mapping_setup->submaps=get_bits(gb, 4)+1;
        } else {
            mapping_setup->submaps=1;
        }

        if (get_bits1(gb)) {
            mapping_setup->coupling_steps=get_bits(gb, 8)+1;
            mapping_setup->magnitude=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));
            mapping_setup->angle=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));
            for(j=0;j<mapping_setup->coupling_steps;++j) {
                mapping_setup->magnitude[j]=get_bits(gb, ilog(vc->audio_channels-1));
                mapping_setup->angle[j]=get_bits(gb, ilog(vc->audio_channels-1));
                // FIXME: sanity checks
            }
        } else {
            mapping_setup->coupling_steps=0;
        }

        AV_DEBUG("   %d mapping coupling steps: %d \n", i, mapping_setup->coupling_steps);

        if(get_bits(gb, 2)) {
            av_log(vc->avccontext, AV_LOG_ERROR, "%d. mapping setup data invalid. \n", i);
            return 1; // following spec.
        }

        if (mapping_setup->submaps>1) {
            mapping_setup->mux=(uint_fast8_t *)av_mallocz(vc->audio_channels * sizeof(uint_fast8_t));
            for(j=0;j<vc->audio_channels;++j) {
                mapping_setup->mux[j]=get_bits(gb, 4);
            }
        }

        for(j=0;j<mapping_setup->submaps;++j) {
            get_bits(gb, 8); // FIXME check?
            mapping_setup->submap_floor[j]=get_bits(gb, 8);
            mapping_setup->submap_residue[j]=get_bits(gb, 8);

            AV_DEBUG("   %d mapping %d submap : floor %d, residue %d \n", i, j, mapping_setup->submap_floor[j], mapping_setup->submap_residue[j]);
        }
    }
    return 0;
}

// Process modes part

static int vorbis_parse_setup_hdr_modes(vorbis_context *vc) {
    GetBitContext *gb=&vc->gb;
    uint_fast8_t i;

    vc->mode_count=get_bits(gb, 6)+1;
    vc->modes=(vorbis_mode *)av_mallocz(vc->mode_count * sizeof(vorbis_mode));

    AV_DEBUG(" There are %d modes.\n", vc->mode_count);

    for(i=0;i<vc->mode_count;++i) {
        vorbis_mode *mode_setup=&vc->modes[i];

        mode_setup->blockflag=get_bits(gb, 1);
        mode_setup->windowtype=get_bits(gb, 16); //FIXME check
        mode_setup->transformtype=get_bits(gb, 16); //FIXME check
        mode_setup->mapping=get_bits(gb, 8); //FIXME check

        AV_DEBUG(" %d mode: blockflag %d, windowtype %d, transformtype %d, mapping %d \n", i, mode_setup->blockflag, mode_setup->windowtype, mode_setup->transformtype, mode_setup->mapping);
    }
    return 0;
}

// Process the whole setup header using the functions above

static int vorbis_parse_setup_hdr(vorbis_context *vc) {
    GetBitContext *gb=&vc->gb;

    if ((get_bits(gb, 8)!='v') || (get_bits(gb, 8)!='o') ||
    (get_bits(gb, 8)!='r') || (get_bits(gb, 8)!='b') ||
    (get_bits(gb, 8)!='i') || (get_bits(gb, 8)!='s')) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (no vorbis signature). \n");
        return 1;
    }

    if (vorbis_parse_setup_hdr_codebooks(vc)) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (codebooks). \n");
        return 2;
    }
    if (vorbis_parse_setup_hdr_tdtransforms(vc)) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (time domain transforms). \n");
        return 3;
    }
    if (vorbis_parse_setup_hdr_floors(vc)) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (floors). \n");
        return 4;
    }
    if (vorbis_parse_setup_hdr_residues(vc)) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (residues). \n");
        return 5;
    }
    if (vorbis_parse_setup_hdr_mappings(vc)) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (mappings). \n");
        return 6;
    }
    if (vorbis_parse_setup_hdr_modes(vc)) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (modes). \n");
        return 7;
    }
    if (!get_bits1(gb)) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (framing flag). \n");
        return 8; // framing flag bit unset error
    }

    return 0;
}

// Process the identification header

static int vorbis_parse_id_hdr(vorbis_context *vc){
    GetBitContext *gb=&vc->gb;
    uint_fast8_t bl0, bl1;
    const float *vwin[8]={ vwin64, vwin128, vwin256, vwin512, vwin1024, vwin2048, vwin4096, vwin8192 };

    if ((get_bits(gb, 8)!='v') || (get_bits(gb, 8)!='o') ||
    (get_bits(gb, 8)!='r') || (get_bits(gb, 8)!='b') ||
    (get_bits(gb, 8)!='i') || (get_bits(gb, 8)!='s')) {
        av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (no vorbis signature). \n");
        return 1;
    }

    vc->version=get_bits_long_le(gb, 32);    //FIXME check 0