/*

 * LCL (LossLess Codec Library) Codec

 * Copyright (c) 2002-2004 Roberto Togni

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file

 * LCL (LossLess Codec Library) Video Codec

 * Decoder for MSZH and ZLIB codecs

 * Experimental encoder for ZLIB RGB24

 *

 * Fourcc: MSZH, ZLIB

 *

 * Original Win32 dll:

 * Ver2.23 By Kenji Oshima 2000.09.20

 * avimszh.dll, avizlib.dll

 *

 * A description of the decoding algorithm can be found here:

 *   http://www.pcisys.net/~melanson/codecs

 *

 * Supports: BGR24 (RGB 24bpp)

 */

#include "config_components.h"

#include <stdio.h>

#include <stdlib.h>

#include "libavutil/attributes.h"

#include "libavutil/mem.h"

#include "libavutil/pixdesc.h"

#include "avcodec.h"

#include "bytestream.h"

#include "codec_internal.h"

#include "lcl.h"

#include "thread.h"

#if CONFIG_ZLIB_DECODER

#include "zlib_wrapper.h"

#include <zlib.h>

#endif

typedef struct LclDecContext {

    // Image type

    int imgtype;

    // Compression type

    int compression;

    // Flags

    int flags;

    // Decompressed data size

    unsigned int decomp_size;

    // Decompression buffer

    unsigned char* decomp_buf;

#if CONFIG_ZLIB_DECODER

    FFZStream zstream;

#endif

} LclDecContext;

/**

 * @param srcptr compressed source buffer, must be padded with at least 5 extra bytes

 * @param destptr must be padded sufficiently for av_memcpy_backptr

 */

static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsigned char * destptr, unsigned int destsize)

{

    unsigned char *destptr_bak = destptr;

    unsigned char *destptr_end = destptr + destsize;

    const unsigned char *srcptr_end = srcptr + srclen;

    unsigned mask = *srcptr++;

    unsigned maskbit = 0x80;

    while (srcptr < srcptr_end && destptr < destptr_end) {

        if (!(mask & maskbit)) {

            memcpy(destptr, srcptr, 4);

            destptr += 4;

            srcptr += 4;

        } else {

            unsigned ofs = bytestream_get_le16(&srcptr);

            unsigned cnt = (ofs >> 11) + 1;

            ofs &= 0x7ff;

            ofs = FFMIN(ofs, destptr - destptr_bak);

            cnt *= 4;

            cnt = FFMIN(cnt, destptr_end - destptr);

            if (ofs) {

                av_memcpy_backptr(destptr, ofs, cnt);

            } else {

                // Not known what the correct behaviour is, but

                // this at least avoids uninitialized data.

                memset(destptr, 0, cnt);

            }

            destptr += cnt;

        }

        maskbit >>= 1;

        if (!maskbit) {

            mask = *srcptr++;

            while (!mask) {

                if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;

                memcpy(destptr, srcptr, 32);

                destptr += 32;

                srcptr += 32;

                mask = *srcptr++;

            }

            maskbit = 0x80;

        }

    }

    if (destptr < destptr_end)

        memset(destptr, 0, destptr_end - destptr);

    return destptr - destptr_bak;

}

#if CONFIG_ZLIB_DECODER

/**

 * @brief decompress a zlib-compressed data block into decomp_buf

 * @param src compressed input buffer

 * @param src_len data length in input buffer

 * @param offset offset in decomp_buf

 * @param expected expected decompressed length

 */

static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)

{

    LclDecContext *c = avctx->priv_data;

    z_stream *const zstream = &c->zstream.zstream;

    int zret = inflateReset(zstream);

    if (zret != Z_OK) {

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

        return AVERROR_UNKNOWN;

    }

    zstream->next_in   = src;

    zstream->avail_in  = src_len;

    zstream->next_out  = c->decomp_buf + offset;

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

    zret = inflate(zstream, Z_FINISH);

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

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

        return AVERROR_UNKNOWN;

    }

    if (expected != (unsigned int)zstream->total_out) {

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

               expected, zstream->total_out);

        if (expected > (unsigned int)zstream->total_out) {

            memset(c->decomp_buf + offset + zstream->total_out, 0,

                   c->decomp_size - offset - zstream->total_out);

            return (unsigned int)zstream->total_out;

        }

        return AVERROR_UNKNOWN;

    }

    return zstream->total_out;

}

#endif

static int decode_frame(AVCodecContext *avctx, AVFrame *frame,

                        int *got_frame, AVPacket *avpkt)

{

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    LclDecContext * const c = avctx->priv_data;

    ptrdiff_t pixel_ptr;

    int row, col;

    unsigned char *encoded = avpkt->data, *outptr;

    uint8_t *y_out, *u_out, *v_out;

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

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

    unsigned int mszh_dlen;

    unsigned char yq, y1q, uq, vq;

    int ret;

    unsigned int mthread_inlen, mthread_outlen;

    unsigned int len = buf_size;

    int linesize, offset;

    if ((ret = ff_thread_get_buffer(avctx, frame, 0)) < 0)

        return ret;

    outptr = frame->data[0]; // Output image pointer

    /* Decompress frame */

    switch (avctx->codec_id) {

    case AV_CODEC_ID_MSZH:

        switch (c->compression) {

        case COMP_MSZH:

            if (c->imgtype == IMGTYPE_RGB24 && len == FFALIGN(width * 3, 4) * height ||

                c->imgtype == IMGTYPE_YUV111 && len == width * height * 3) {

                ;

            } else if (c->flags & FLAG_MULTITHREAD) {

                mthread_inlen = AV_RL32(buf);

                if (len < 8 || len - 8 < mthread_inlen) {

                    av_log(avctx, AV_LOG_ERROR, "len %d is too small\n", len);

                    return AVERROR_INVALIDDATA;

                }

                mthread_outlen = AV_RL32(buf + 4);

                mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);

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

                if (mthread_outlen != mszh_dlen) {

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

                           mthread_outlen, mszh_dlen);

                    return AVERROR_INVALIDDATA;

                }

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

                                        c->decomp_buf + mthread_outlen, c->decomp_size - mthread_outlen);

                if (mthread_outlen != mszh_dlen) {

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

                           mthread_outlen, mszh_dlen);

                    return AVERROR_INVALIDDATA;

                }

                encoded = c->decomp_buf;

                len = c->decomp_size;

            } else {

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

                if (c->decomp_size != mszh_dlen) {

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

                           c->decomp_size, mszh_dlen);

                    if (c->decomp_size != mszh_dlen &&

                        c->decomp_size != mszh_dlen + 2) // YUV420 306x306 is missing 2 bytes

                        return AVERROR_INVALIDDATA;

                }

                encoded = c->decomp_buf;

                len = mszh_dlen;

            }

            break;

        case COMP_MSZH_NOCOMP: {

            int bppx2;

            int aligned_width = width;

            switch (c->imgtype) {

            case IMGTYPE_YUV111:

            case IMGTYPE_RGB24:

                bppx2 = 6;

                break;

            case IMGTYPE_YUV422:

                aligned_width &= ~3;

                av_fallthrough;

            case IMGTYPE_YUV211:

                bppx2 = 4;

                break;

            case IMGTYPE_YUV411:

                aligned_width &= ~3;

                av_fallthrough;

            case IMGTYPE_YUV420:

                bppx2 = 3;

                break;

            default:

                bppx2 = 0; // will error out below

                break;

            }

            if (len < ((aligned_width * height * bppx2) >> 1))

                return AVERROR_INVALIDDATA;

            break;

        }

        default:

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

            return AVERROR_INVALIDDATA;

        }

        break;

#if CONFIG_ZLIB_DECODER

    case AV_CODEC_ID_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) {

            if (c->flags & FLAG_PNGFILTER) {

                memcpy(c->decomp_buf, buf, len);

                encoded = c->decomp_buf;

            } else {

                break;

            }

        } else if (c->flags & FLAG_MULTITHREAD) {

            mthread_inlen = AV_RL32(buf);

            mthread_inlen = FFMIN(mthread_inlen, len - 8);

            mthread_outlen = AV_RL32(buf + 4);

            mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);

            ret = zlib_decomp(avctx, buf + 8, mthread_inlen, 0, mthread_outlen);

            if (ret < 0) return ret;

            ret = zlib_decomp(avctx, buf + 8 + mthread_inlen, len - 8 - mthread_inlen,

                              mthread_outlen, mthread_outlen);

            if (ret < 0) return ret;

            memset(c->decomp_buf + mthread_outlen + ret, 0,

                   c->decomp_size - mthread_outlen - ret);

            len = c->decomp_size;

        } else {

            int ret = zlib_decomp(avctx, buf, len, 0, c->decomp_size);

            if (ret < 0) return ret;

            len = ret;

        }

        encoded = c->decomp_buf;

        break;

#endif

    default:

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

        return AVERROR_INVALIDDATA;

    }

    /* Apply PNG filter */

    if (avctx->codec_id == AV_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++];

                unsigned uqvq = AV_RL16(encoded+pixel_ptr);

                pixel_ptr += 2;

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

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

                    uqvq -= AV_RL16(encoded+pixel_ptr+1);

                    AV_WL16(encoded+pixel_ptr+1, uqvq);

                    pixel_ptr += 3;

                }

            }

            break;

        case IMGTYPE_YUV422:

            pixel_ptr = 0;

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

                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:

            pixel_ptr = 0;

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

                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 AVERROR_INVALIDDATA;

        }

    }

    /* Convert colorspace */

    y_out = frame->data[0] + (height - 1) * frame->linesize[0];

    offset = (height - 1) * frame->linesize[1];

    u_out = FF_PTR_ADD(frame->data[1], offset);

    offset = (height - 1) * frame->linesize[2];

    v_out = FF_PTR_ADD(frame->data[2], offset);

    switch (c->imgtype) {

    case IMGTYPE_YUV111:

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

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

                y_out[col] = *encoded++;

                u_out[col] = *encoded++ + 128;

                v_out[col] = *encoded++ + 128;

            }

            y_out -= frame->linesize[0];

            u_out -= frame->linesize[1];

            v_out -= frame->linesize[2];

        }

        break;

    case IMGTYPE_YUV422:

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

            for (col = 0; col < width - 3; col += 4) {

                memcpy(y_out + col, encoded, 4);

                encoded += 4;

                u_out[ col >> 1     ] = *encoded++ + 128;

                u_out[(col >> 1) + 1] = *encoded++ + 128;

                v_out[ col >> 1     ] = *encoded++ + 128;

                v_out[(col >> 1) + 1] = *encoded++ + 128;

            }

            if (col && col < width) {

                u_out[ col >> 1     ] = u_out[(col>>1) - 1];

                v_out[ col >> 1     ] = v_out[(col>>1) - 1];

            }

            y_out -= frame->linesize[0];

            u_out -= frame->linesize[1];

            v_out -= frame->linesize[2];

        }

        break;

    case IMGTYPE_RGB24:

        linesize = len < FFALIGN(3 * width, 4) * height ? 3 * width : FFALIGN(3 * width, 4);

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

            pixel_ptr = row * frame->linesize[0];

            memcpy(outptr + pixel_ptr, encoded, 3 * width);

            encoded += linesize;

        }

        break;

    case IMGTYPE_YUV411:

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

            for (col = 0; col < width - 3; col += 4) {

                memcpy(y_out + col, encoded, 4);

                encoded += 4;

                u_out[col >> 2] = *encoded++ + 128;

                v_out[col >> 2] = *encoded++ + 128;

            }

            if (col && col < width) {

                u_out[col >> 2] = u_out[(col>>2) - 1];

                v_out[col >> 2] = v_out[(col>>2) - 1];

            }

            y_out -= frame->linesize[0];

            u_out -= frame->linesize[1];

            v_out -= frame->linesize[2];

        }

        break;

    case IMGTYPE_YUV211:

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

            for (col = 0; col < width - 1; col += 2) {

                memcpy(y_out + col, encoded, 2);

                encoded += 2;

                u_out[col >> 1] = *encoded++ + 128;

                v_out[col >> 1] = *encoded++ + 128;

            }

            y_out -= frame->linesize[0];

            u_out -= frame->linesize[1];

            v_out -= frame->linesize[2];

        }

        break;

    case IMGTYPE_YUV420:

        u_out = frame->data[1] + ((height >> 1) - 1) * frame->linesize[1];

        v_out = frame->data[2] + ((height >> 1) - 1) * frame->linesize[2];

        for (row = 0; row < height - 1; row += 2) {

            for (col = 0; col < width - 1; col += 2) {

                memcpy(y_out + col, encoded, 2);

                encoded += 2;

                memcpy(y_out + col - frame->linesize[0], encoded, 2);

                encoded += 2;

                u_out[col >> 1] = *encoded++ + 128;

                v_out[col >> 1] = *encoded++ + 128;

            }

            y_out -= frame->linesize[0] << 1;

            u_out -= frame->linesize[1];

            v_out -= frame->linesize[2];

        }

        break;

    default:

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

        return AVERROR_INVALIDDATA;

    }

    *got_frame = 1;

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

    return buf_size;

}

static av_cold int decode_init(AVCodecContext *avctx)

{

    LclDecContext * const c = avctx->priv_data;

    unsigned int basesize = avctx->width * avctx->height;

    unsigned int max_basesize = FFALIGN(avctx->width,  4) *

                                FFALIGN(avctx->height, 4);

    unsigned int max_decomp_size;

    int subsample_h, subsample_v;

    int partial_h_supported = 0;

    if (avctx->extradata_size < 8) {

        av_log(avctx, AV_LOG_ERROR, "Extradata size too small.\n");

        return AVERROR_INVALIDDATA;

    }

    /* Check codec type */

    if ((avctx->codec_id == AV_CODEC_ID_MSZH  && avctx->extradata[7] != CODEC_MSZH) ||

        (avctx->codec_id == AV_CODEC_ID_ZLIB  && avctx->extradata[7] != CODEC_ZLIB)) {

        av_log(avctx, AV_LOG_ERROR, "Codec id and codec type mismatch. This should not happen.\n");

    }

    /* Detect image type */

    switch (c->imgtype = avctx->extradata[4]) {

    case IMGTYPE_YUV111:

        c->decomp_size = basesize * 3;

        max_decomp_size = max_basesize * 3;

        avctx->pix_fmt = AV_PIX_FMT_YUV444P;

        av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 1:1:1.\n");

        break;

    case IMGTYPE_YUV422:

        c->decomp_size = (avctx->width & ~3) * avctx->height * 2;

        max_decomp_size = max_basesize * 2;

        avctx->pix_fmt = AV_PIX_FMT_YUV422P;

        av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:2.\n");

        partial_h_supported = 1;

        break;

    case IMGTYPE_RGB24:

        c->decomp_size = FFALIGN(avctx->width*3, 4) * avctx->height;

        max_decomp_size = max_basesize * 3;

        avctx->pix_fmt = AV_PIX_FMT_BGR24;

        av_log(avctx, AV_LOG_DEBUG, "Image type is RGB 24.\n");

        break;

    case IMGTYPE_YUV411:

        c->decomp_size = (avctx->width & ~3) * avctx->height / 2 * 3;

        max_decomp_size = max_basesize / 2 * 3;

        avctx->pix_fmt = AV_PIX_FMT_YUV411P;

        av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:1:1.\n");

        partial_h_supported = 1;

        break;

    case IMGTYPE_YUV211:

        c->decomp_size = basesize * 2;

        max_decomp_size = max_basesize * 2;

        avctx->pix_fmt = AV_PIX_FMT_YUV422P;

        av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 2:1:1.\n");

        break;

    case IMGTYPE_YUV420:

        c->decomp_size = basesize / 2 * 3;

        max_decomp_size = max_basesize / 2 * 3;

        avctx->pix_fmt = AV_PIX_FMT_YUV420P;

        av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:0.\n");

        break;

    default:

        av_log(avctx, AV_LOG_ERROR, "Unsupported image format %d.\n", c->imgtype);

        return AVERROR_INVALIDDATA;

    }

    av_pix_fmt_get_chroma_sub_sample(avctx->pix_fmt, &subsample_h, &subsample_v);

    if ((avctx->width % (1<<subsample_h) && !partial_h_supported) || avctx->height % (1<<subsample_v)) {

        avpriv_request_sample(avctx, "Unsupported dimensions");

        return AVERROR_INVALIDDATA;

    }

    /* Detect compression method */

    c->compression = (int8_t)avctx->extradata[5];

    switch (avctx->codec_id) {

    case AV_CODEC_ID_MSZH:

        switch (c->compression) {

        case COMP_MSZH:

            av_log(avctx, AV_LOG_DEBUG, "Compression enabled.\n");

            break;

        case COMP_MSZH_NOCOMP:

            c->decomp_size = 0;

            av_log(avctx, AV_LOG_DEBUG, "No compression.\n");

            break;

        default:

            av_log(avctx, AV_LOG_ERROR, "Unsupported compression format for MSZH (%d).\n", c->compression);

            return AVERROR_INVALIDDATA;

        }

        break;

#if CONFIG_ZLIB_DECODER

    case AV_CODEC_ID_ZLIB:

        switch (c->compression) {

        case COMP_ZLIB_HISPEED:

            av_log(avctx, AV_LOG_DEBUG, "High speed compression.\n");

            break;

        case COMP_ZLIB_HICOMP:

            av_log(avctx, AV_LOG_DEBUG, "High compression.\n");

            break;

        case COMP_ZLIB_NORMAL:

            av_log(avctx, AV_LOG_DEBUG, "Normal compression.\n");

            break;

        default:

            if (c->compression < Z_NO_COMPRESSION || c->compression > Z_BEST_COMPRESSION) {

                av_log(avctx, AV_LOG_ERROR, "Unsupported compression level for ZLIB: (%d).\n", c->compression);

                return AVERROR_INVALIDDATA;

            }

            av_log(avctx, AV_LOG_DEBUG, "Compression level for ZLIB: (%d).\n", c->compression);

        }

        break;

#endif

    default:

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

        return AVERROR_INVALIDDATA;

    }

    /* Allocate decompression buffer */

    if (c->decomp_size) {

        if (!(c->decomp_buf = av_malloc(max_decomp_size))) {

            av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");

            return AVERROR(ENOMEM);

        }

    }

    /* Detect flags */

    c->flags = avctx->extradata[6];

    if (c->flags & FLAG_MULTITHREAD)

        av_log(avctx, AV_LOG_DEBUG, "Multithread encoder flag set.\n");

    if (c->flags & FLAG_NULLFRAME)

        av_log(avctx, AV_LOG_DEBUG, "Nullframe insertion flag set.\n");

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

        av_log(avctx, AV_LOG_DEBUG, "PNG filter flag set.\n");

    if (c->flags & FLAGMASK_UNUSED)

        av_log(avctx, AV_LOG_ERROR, "Unknown flag set (%d).\n", c->flags);

    /* If needed init zlib */

#if CONFIG_ZLIB_DECODER

    if (avctx->codec_id == AV_CODEC_ID_ZLIB)

        return ff_inflate_init(&c->zstream, avctx);

#endif

    return 0;

}

static av_cold int decode_end(AVCodecContext *avctx)

{

    LclDecContext * const c = avctx->priv_data;

    av_freep(&c->decomp_buf);

#if CONFIG_ZLIB_DECODER

    ff_inflate_end(&c->zstream);

#endif

    return 0;

}

#if CONFIG_MSZH_DECODER

const FFCodec ff_mszh_decoder = {

    .p.name         = "mszh",

    CODEC_LONG_NAME("LCL (LossLess Codec Library) MSZH"),

    .p.type         = AVMEDIA_TYPE_VIDEO,

    .p.id           = AV_CODEC_ID_MSZH,

    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,

    .priv_data_size = sizeof(LclDecContext),

    .init           = decode_init,

    .close          = decode_end,

    FF_CODEC_DECODE_CB(decode_frame),

    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,

};

#endif

#if CONFIG_ZLIB_DECODER

const FFCodec ff_zlib_decoder = {

    .p.name         = "zlib",

    CODEC_LONG_NAME("LCL (LossLess Codec Library) ZLIB"),

    .p.type         = AVMEDIA_TYPE_VIDEO,

    .p.id           = AV_CODEC_ID_ZLIB,

    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,

    .priv_data_size = sizeof(LclDecContext),

    .init           = decode_init,

    .close          = decode_end,

    FF_CODEC_DECODE_CB(decode_frame),

    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,

};

#endif