Function decode_frame

libavcodec/cscd.c:137–215

#endif

static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
                        AVPacket *avpkt) {
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
    CamStudioContext *c = avctx->priv_data;
    AVFrame *picture = data;

    if (buf_size < 2) {
        av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
        return -1;
    }

    if (c->pic.data[0])
        avctx->release_buffer(avctx, &c->pic);
    c->pic.reference = 1;
    c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_READABLE |
                          FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
    if (avctx->get_buffer(avctx, &c->pic) < 0) {
        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
        return -1;
    }

    // decompress data
    switch ((buf[0] >> 1) & 7) {
        case 0: { // lzo compression
            int outlen = c->decomp_size, inlen = buf_size - 2;
            if (av_lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen))
                av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
            break;
        }
        case 1: { // zlib compression
#if CONFIG_ZLIB
            unsigned long dlen = c->decomp_size;
            if (uncompress(c->decomp_buf, &dlen, &buf[2], buf_size - 2) != Z_OK)
                av_log(avctx, AV_LOG_ERROR, "error during zlib decompression\n");
            break;
#else
            av_log(avctx, AV_LOG_ERROR, "compiled without zlib support\n");
            return -1;
#endif
        }
        default:
            av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
            return -1;
    }

    // flip upside down, add difference frame
    if (buf[0] & 1) { // keyframe
        c->pic.pict_type = FF_I_TYPE;
        c->pic.key_frame = 1;
        switch (c->bpp) {
          case 16:
              copy_frame_16(&c->pic, c->decomp_buf, c->linelen, c->height);
              break;
          case 32:
              copy_frame_32(&c->pic, c->decomp_buf, c->linelen, c->height);
              break;
          default: