static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size)

{

	LclContext * const c = (LclContext *)avctx->priv_data;

	unsigned char *encoded = (unsigned char *)buf;

    int pixel_ptr;

    int row, col;

    unsigned char *outptr;

    unsigned int width = avctx->width; // Real image width

    unsigned int height = avctx->height; // Real image height

    unsigned int mszh_dlen;

    unsigned char yq, y1q, uq, vq;

    int uqvq;

    unsigned int mthread_inlen, mthread_outlen;

#ifdef CONFIG_ZLIB

    int zret; // Zlib return code

#endif

    int len = buf_size;



	/* no supplementary picture */

	if (buf_size == 0)

		return 0;



	if(c->pic.data[0])

		avctx->release_buffer(avctx, &c->pic);



	c->pic.reference = 0;

	c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;

	if(avctx->get_buffer(avctx, &c->pic) < 0){

		av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

		return -1;

	}



    outptr = c->pic.data[0]; // Output image pointer



    /* Decompress frame */

    switch (avctx->codec_id) {

        case CODEC_ID_MSZH:

            switch (c->compression) {

                case COMP_MSZH:

                    if (c->flags & FLAG_MULTITHREAD) {

                        mthread_inlen = *((unsigned int*)encoded);

                        mthread_outlen = *((unsigned int*)(encoded+4));

                        mszh_dlen = mszh_decomp(encoded + 8, mthread_inlen, c->decomp_buf);

                        if (mthread_outlen != mszh_dlen) {

                            av_log(avctx, AV_LOG_ERROR, "Mthread1 decoded size differs (%d != %d)\n",

                                   mthread_outlen, mszh_dlen);

                        }

                        mszh_dlen = mszh_decomp(encoded + 8 + mthread_inlen, len - mthread_inlen,

                                                c->decomp_buf + mthread_outlen);

                        if ((c->decomp_size - mthread_outlen) != mszh_dlen) {

                            av_log(avctx, AV_LOG_ERROR, "Mthread2 decoded size differs (%d != %d)\n",

                                   c->decomp_size - mthread_outlen, mszh_dlen);

                        }

                        encoded = c->decomp_buf;

                        len = c->decomp_size;

                    } else {

                        mszh_dlen = mszh_decomp(encoded, len, c->decomp_buf);

                        if (c->decomp_size != mszh_dlen) {

                            av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %d)\n",

                                   c->decomp_size, mszh_dlen);

                        }

                        encoded = c->decomp_buf;

                        len = mszh_dlen;

                    }

                    break;

                case COMP_MSZH_NOCOMP:

                    break;

                default:

                    av_log(avctx, AV_LOG_ERROR, "BUG! Unknown MSZH compression in frame decoder.\n");

                    return -1;

            }

            break;

        case CODEC_ID_ZLIB:

#ifdef CONFIG_ZLIB

            /* Using the original dll with normal compression (-1) and RGB format

             * gives a file with ZLIB fourcc, but frame is really uncompressed.

             * To be sure that's true check also frame size */

            if ((c->compression == COMP_ZLIB_NORMAL) && (c->imgtype == IMGTYPE_RGB24) &&

               (len == width * height * 3))

                break;

            zret = inflateReset(&(c->zstream));

            if (zret != Z_OK) {

                av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);

                return -1;

            }

            if (c->flags & FLAG_MULTITHREAD) {

                mthread_inlen = *((unsigned int*)encoded);

                mthread_outlen = *((unsigned int*)(encoded+4));

                c->zstream.next_in = encoded + 8;

                c->zstream.avail_in = mthread_inlen;

                c->zstream.next_out = c->decomp_buf;

                c->zstream.avail_out = mthread_outlen;    

                zret = inflate(&(c->zstream), Z_FINISH);

                if ((zret != Z_OK) && (zret != Z_STREAM_END)) {

                    av_log(avctx, AV_LOG_ERROR, "Mthread1 inflate error: %d\n", zret);

                    return -1;

                }

                if (mthread_outlen != (unsigned int)(c->zstream.total_out)) {

                    av_log(avctx, AV_LOG_ERROR, "Mthread1 decoded size differs (%u != %lu)\n",

                           mthread_outlen, c->zstream.total_out);

                }

                zret = inflateReset(&(c->zstream));

                if (zret != Z_OK) {

                    av_log(avctx, AV_LOG_ERROR, "Mthread2 inflate reset error: %d\n", zret);

                    return -1;

                }

                c->zstream.next_in = encoded + 8 + mthread_inlen;

                c->zstream.avail_in = len - mthread_inlen;

                c->zstream.next_out = c->decomp_buf + mthread_outlen;

                c->zstream.avail_out = mthread_outlen;    

                zret = inflate(&(c->zstream), Z_FINISH);

                if ((zret != Z_OK) && (zret != Z_STREAM_END)) {

                    av_log(avctx, AV_LOG_ERROR, "Mthread2 inflate error: %d\n", zret);

                    return -1;

                }

                if ((c->decomp_size - mthread_outlen) != (unsigned int)(c->zstream.total_out)) {

                    av_log(avctx, AV_LOG_ERROR, "Mthread2 decoded size differs (%d != %lu)\n",

                           c->decomp_size - mthread_outlen, c->zstream.total_out);

                }

            } else {

                c->zstream.next_in = encoded;

                c->zstream.avail_in = len;

                c->zstream.next_out = c->decomp_buf;

                c->zstream.avail_out = c->decomp_size;

                zret = inflate(&(c->zstream), Z_FINISH);

                if ((zret != Z_OK) && (zret != Z_STREAM_END)) {

                    av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);

                    return -1;

                }

                if (c->decomp_size != (unsigned int)(c->zstream.total_out)) {

                    av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %lu)\n",

                           c->decomp_size, c->zstream.total_out);

                }

            }

            encoded = c->decomp_buf;

            len = c->decomp_size;;

#else

            av_log(avctx, AV_LOG_ERROR, "BUG! Zlib support not compiled in frame decoder.\n");

            return -1;

#endif

            break;

        default:

            av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in frame decoder compression switch.\n");

            return -1;

    }





    /* Apply PNG filter */

    if ((avctx->codec_id == CODEC_ID_ZLIB) && (c->flags & FLAG_PNGFILTER)) {

        switch (c->imgtype) {

            case IMGTYPE_YUV111:

            case IMGTYPE_RGB24:

                for (row = 0; row < height; row++) {

                    pixel_ptr = row * width * 3;

                    yq = encoded[pixel_ptr++];

                    uqvq = encoded[pixel_ptr++];

              	  uqvq+=(encoded[pixel_ptr++] << 8);

                    for (col = 1; col < width; col++) {

                        encoded[pixel_ptr] = yq -= encoded[pixel_ptr];

                        uqvq -= (encoded[pixel_ptr+1] | (encoded[pixel_ptr+2]<<8));

                        encoded[pixel_ptr+1] = (uqvq) & 0xff;

                        encoded[pixel_ptr+2] = ((uqvq)>>8) & 0xff;

                        pixel_ptr += 3;

                    }

                }

                break;

            case IMGTYPE_YUV422:

                for (row = 0; row < height; row++) {

                    pixel_ptr = row * width * 2;

                    yq = uq = vq =0;

                    for (col = 0; col < width/4; col++) {

                        encoded[pixel_ptr] = yq -= encoded[pixel_ptr];

                        encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];

                        encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];

                        encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];

                        encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];

                        encoded[pixel_ptr+5] = uq -= encoded[pixel_ptr+5];

                        encoded[pixel_ptr+6] = vq -= encoded[pixel_ptr+6];

                        encoded[pixel_ptr+7] = vq -= encoded[pixel_ptr+7];

                        pixel_ptr += 8;

                    }

                }

                break;

            case IMGTYPE_YUV411:

                for (row = 0; row < height; row++) {

                    pixel_ptr = row * width / 2 * 3;

                    yq = uq = vq =0;

                    for (col = 0; col < width/4; col++) {

                        encoded[pixel_ptr] = yq -= encoded[pixel_ptr];

                        encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];

                        encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];

                        encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];

                        encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];

                        encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];

                        pixel_ptr += 6;

                    }

                }

                break;

            case IMGTYPE_YUV211:

                for (row = 0; row < height; row++) {

                    pixel_ptr = row * width * 2;

                    yq = uq = vq =0;

                    for (col = 0; col < width/2; col++) {

                        encoded[pixel_ptr] = yq -= encoded[pixel_ptr];

                        encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];

                        encoded[pixel_ptr+2] = uq -= encoded[pixel_ptr+2];

                        encoded[pixel_ptr+3] = vq -= encoded[pixel_ptr+3];

                        pixel_ptr += 4;

                    }

                }

                break;

            case IMGTYPE_YUV420:

                for (row = 0; row < height/2; row++) {

                    pixel_ptr = row * width * 3;

                    yq = y1q = uq = vq =0;

                    for (col = 0; col < width/2; col++) {

                        encoded[pixel_ptr] = yq -= encoded[pixel_ptr];

                        encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];

                        encoded[pixel_ptr+2] = y1q -= encoded[pixel_ptr+2];

                        encoded[pixel_ptr+3] = y1q -= encoded[pixel_ptr+3];

                        encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];

                        encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];

                        pixel_ptr += 6;

                    }

                }

                break;

            default:

                av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in pngfilter switch.\n");

                return -1;

        }

    }



    /* Convert colorspace */

    switch (c->imgtype) {

        case IMGTYPE_YUV111:

            for (row = height - 1; row >= 0; row--) {

                pixel_ptr = row * c->pic.linesize[0];

                for (col = 0; col < width; col++) {

                    outptr[pixel_ptr++] = get_b(encoded[0], encoded[1]);

                    outptr[pixel_ptr++] = get_g(encoded[0], encoded[1], encoded[2]);

                    outptr[pixel_ptr++] = get_r(encoded[0], encoded[2]);

                    encoded += 3;

                }

            }

            break;

        case IMGTYPE_YUV422:

            for (row = height - 1; row >= 0; row--) {

                pixel_ptr = row * c->pic.linesize[0];

                for (col = 0; col < width/4; col++) {

                    outptr[pixel_ptr++] = get_b(encoded[0], encoded[4]);

                    outptr[pixel_ptr++] = get_g(encoded[0], encoded[4], encoded[6]);

                    outptr[pixel_ptr++] = get_r(encoded[0], encoded[6]);

                    outptr[pixel_ptr++] = get_b(encoded[1], encoded[4]);

                    outptr[pixel_ptr++] = get_g(encoded[1], encoded[4], encoded[6]);

                    outptr[pixel_ptr++] = get_r(encoded[1], encoded[6]);

                    outptr[pixel_ptr++] = get_b(encoded[2], encoded[5]);

                    outptr[pixel_ptr++] = get_g(encoded[2], encoded[5], encoded[7]);

                    outptr[pixel_ptr++] = get_r(encoded[2], encoded[7]);

                    outptr[pixel_ptr++] = get_b(encoded[3], encoded[5]);

                    outptr[pixel_ptr++] = get_g(encoded[3], encoded[5], encoded[7]);

                    outptr[pixel_ptr++] = get_r(encoded[3], encoded[7]);

                    encoded += 8;

                }

            }

            break;

        case IMGTYPE_RGB24:

            for (row = height - 1; row >= 0; row--) {

                pixel_ptr = row * c->pic.linesize[0];

                for (col = 0; col < width; col++) {

                    outptr[pixel_ptr++] = encoded[0];

                    outptr[pixel_ptr++] = encoded[1];

                    outptr[pixel_ptr++] = encoded[2];

                    encoded += 3;

                }

            }

            break;

        case IMGTYPE_YUV411:

            for (row = height - 1; row >= 0; row--) {

                pixel_ptr = row * c->pic.linesize[0];

                for (col = 0; col < width/4; col++) {

                    outptr[pixel_ptr++] = get_b(encoded[0], encoded[4]);

                    outptr[pixel_ptr++] = get_g(encoded[0], encoded[4], encoded[5]);

                    outptr[pixel_ptr++] = get_r(encoded[0], encoded[5]);

                    outptr[pixel_ptr++] = get_b(encoded[1], encoded[4]);

                    outptr[pixel_ptr++] = get_g(encoded[1], encoded[4], encoded[5]);

                    outptr[pixel_ptr++] = get_r(encoded[1], encoded[5]);

                    outptr[pixel_ptr++] = get_b(encoded[2], encoded[4]);

                    outptr[pixel_ptr++] = get_g(encoded[2], encoded[4], encoded[5]);

                    outptr[pixel_ptr++] = get_r(encoded[2], encoded[5]);

                    outptr[pixel_ptr++] = get_b(encoded[3], encoded[4]);

                    outptr[pixel_ptr++] = get_g(encoded[3], encoded[4], encoded[5]);

                    outptr[pixel_ptr++] = get_r(encoded[3], encoded[5]);

                    encoded += 6;

                }

            }

            break;

        case IMGTYPE_YUV211:

            for (row = height - 1; row >= 0; row--) {

                pixel_ptr = row * c->pic.linesize[0];

                for (col = 0; col < width/2; col++) {

                    outptr[pixel_ptr++] = get_b(encoded[0], encoded[2]);

                    outptr[pixel_ptr++] = get_g(encoded[0], encoded[2], encoded[3]);

                    outptr[pixel_ptr++] = get_r(encoded[0], encoded[3]);

                    outptr[pixel_ptr++] = get_b(encoded[1], encoded[2]);

                    outptr[pixel_ptr++] = get_g(encoded[1], encoded[2], encoded[3]);

                    outptr[pixel_ptr++] = get_r(encoded[1], encoded[3]);

                    encoded += 4;

                }

            }

            break;

        case IMGTYPE_YUV420:

            for (row = height / 2 - 1; row >= 0; row--) {

                pixel_ptr = 2 * row * c->pic.linesize[0];

                for (col = 0; col < width/2; col++) {

                    outptr[pixel_ptr] = get_b(encoded[0], encoded[4]);

                    outptr[pixel_ptr+1] = get_g(encoded[0], encoded[4], encoded[5]);

                    outptr[pixel_ptr+2] = get_r(encoded[0], encoded[5]);

                    outptr[pixel_ptr+3] = get_b(encoded[1], encoded[4]);

                    outptr[pixel_ptr+4] = get_g(encoded[1], encoded[4], encoded[5]);

                    outptr[pixel_ptr+5] = get_r(encoded[1], encoded[5]);

                    outptr[pixel_ptr-c->pic.linesize[0]] = get_b(encoded[2], encoded[4]);

                    outptr[pixel_ptr-c->pic.linesize[0]+1] = get_g(encoded[2], encoded[4], encoded[5]);

                    outptr[pixel_ptr-c->pic.linesize[0]+2] = get_r(encoded[2], encoded[5]);

                    outptr[pixel_ptr-c->pic.linesize[0]+3] = get_b(encoded[3], encoded[4]);

                    outptr[pixel_ptr-c->pic.linesize[0]+4] = get_g(encoded[3], encoded[4], encoded[5]);

                    outptr[pixel_ptr-c->pic.linesize[0]+5] = get_r(encoded[3], encoded[5]);

                    pixel_ptr += 6;

                    encoded += 6;

                }

            }

            break;

        default:

            av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in image decoder.\n");

            return -1;

    }



    *data_size = sizeof(AVFrame);

    *(AVFrame*)data = c->pic;



    /* always report that the buffer was completely consumed */

    return buf_size;

}
