Function wavpack_decode_frame

libavcodec/wavpack.c:675–1019

}

static int wavpack_decode_frame(AVCodecContext *avctx,
                            void *data, int *data_size,
                            AVPacket *avpkt)
{
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
    WavpackContext *s = avctx->priv_data;
    void *samples = data;
    int samplecount;
    int got_terms = 0, got_weights = 0, got_samples = 0, got_entropy = 0, got_bs = 0, got_float = 0;
    int got_hybrid = 0;
    const uint8_t* buf_end = buf + buf_size;
    int i, j, id, size, ssize, weights, t;
    int bpp;

    if (buf_size == 0){
        *data_size = 0;
        return 0;
    }

    if(!s->samples_left){
        memset(s->decorr, 0, MAX_TERMS * sizeof(Decorr));
        memset(s->ch, 0, sizeof(s->ch));
        s->extra_bits = 0;
        s->and = s->or = s->shift = 0;
        s->got_extra_bits = 0;
    }

    s->samples = AV_RL32(buf); buf += 4;
    if(!s->samples){
        *data_size = 0;
        return buf_size;
    }
    s->frame_flags = AV_RL32(buf); buf += 4;
    if(s->frame_flags&0x80){
        bpp = sizeof(float);
        avctx->sample_fmt = SAMPLE_FMT_FLT;
    } else if((s->frame_flags&0x03) <= 1){
        bpp = 2;
        avctx->sample_fmt = SAMPLE_FMT_S16;
    } else {
        bpp = 4;
        avctx->sample_fmt = SAMPLE_FMT_S32;
    }
    s->stereo_in = (s->frame_flags & WV_FALSE_STEREO) ? 0 : s->stereo;
    s->joint = s->frame_flags & WV_JOINT_STEREO;
    s->hybrid = s->frame_flags & WV_HYBRID_MODE;
    s->hybrid_bitrate = s->frame_flags & WV_HYBRID_BITRATE;
    s->post_shift = 8 * (bpp-1-(s->frame_flags&0x03)) + ((s->frame_flags >> 13) & 0x1f);
    s->CRC = AV_RL32(buf); buf += 4;

    s->max_samples = *data_size / (bpp * avctx->channels);
    s->max_samples = FFMIN(s->max_samples, s->samples);
    if(s->samples_left > 0){
        s->max_samples = FFMIN(s->max_samples, s->samples_left);
        buf = buf_end;
    }