Function cook_decode_init

libavcodec/cook.c:1082–1285

 */

static av_cold int cook_decode_init(AVCodecContext *avctx)
{
    COOKContext *q = avctx->priv_data;
    const uint8_t *edata_ptr = avctx->extradata;
    const uint8_t *edata_ptr_end = edata_ptr + avctx->extradata_size;
    int extradata_size = avctx->extradata_size;
    int s = 0;
    unsigned int channel_mask = 0;
    q->avctx = avctx;

    /* Take care of the codec specific extradata. */
    if (extradata_size <= 0) {
        av_log(avctx,AV_LOG_ERROR,"Necessary extradata missing!\n");
        return -1;
    }
    av_log(avctx,AV_LOG_DEBUG,"codecdata_length=%d\n",avctx->extradata_size);

    /* Take data from the AVCodecContext (RM container). */
    q->sample_rate = avctx->sample_rate;
    q->nb_channels = avctx->channels;
    q->bit_rate = avctx->bit_rate;

    /* Initialize RNG. */
    av_lfg_init(&q->random_state, 0);

    while(edata_ptr < edata_ptr_end){
        /* 8 for mono, 16 for stereo, ? for multichannel
           Swap to right endianness so we don't need to care later on. */
        if (extradata_size >= 8){
            q->subpacket[s].cookversion = bytestream_get_be32(&edata_ptr);
            q->subpacket[s].samples_per_frame =  bytestream_get_be16(&edata_ptr);
            q->subpacket[s].subbands = bytestream_get_be16(&edata_ptr);
            extradata_size -= 8;
        }
        if (avctx->extradata_size >= 8){
            bytestream_get_be32(&edata_ptr);    //Unknown unused
            q->subpacket[s].js_subband_start = bytestream_get_be16(&edata_ptr);
            q->subpacket[s].js_vlc_bits = bytestream_get_be16(&edata_ptr);
            extradata_size -= 8;
        }

        /* Initialize extradata related variables. */
        q->subpacket[s].samples_per_channel = q->subpacket[s].samples_per_frame / q->nb_channels;
        q->subpacket[s].bits_per_subpacket = avctx->block_align * 8;

        /* Initialize default data states. */
        q->subpacket[s].log2_numvector_size = 5;
        q->subpacket[s].total_subbands = q->subpacket[s].subbands;
        q->subpacket[s].num_channels = 1;

        /* Initialize version-dependent variables */

        av_log(avctx,AV_LOG_DEBUG,"subpacket[%i].cookversion=%x\n",s,q->subpacket[s].cookversion);
        q->subpacket[s].joint_stereo = 0;
        switch (q->subpacket[s].cookversion) {
            case MONO:
                if (q->nb_channels != 1) {
                    av_log(avctx,AV_LOG_ERROR,"Container channels != 1, report sample!\n");