libavcodec/lcldec.c

   1 /*
   2  * LCL (LossLess Codec Library) Codec
   3  * Copyright (c) 2002-2004 Roberto Togni
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file
  24  * LCL (LossLess Codec Library) Video Codec
  25  * Decoder for MSZH and ZLIB codecs
  26  * Experimental encoder for ZLIB RGB24
  27  *
  28  * Fourcc: MSZH, ZLIB
  29  *
  30  * Original Win32 dll:
  31  * Ver2.23 By Kenji Oshima 2000.09.20
  32  * avimszh.dll, avizlib.dll
  33  *
  34  * A description of the decoding algorithm can be found here:
  35  *   http://www.pcisys.net/~melanson/codecs
  36  *
  37  * Supports: BGR24 (RGB 24bpp)
  38  *
  39  */
  40
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43
  44 #include "libavutil/mem.h"
  45 #include "avcodec.h"
  46 #include "bytestream.h"
  47 #include "internal.h"
  48 #include "lcl.h"
  49
  50 #if CONFIG_ZLIB_DECODER
  51 #include <zlib.h>
  52 #endif
  53
  54 /*
  55  * Decoder context
  56  */
  57 typedef struct LclDecContext {
  58     AVFrame pic;
  59
  60     // Image type
  61     int imgtype;
  62     // Compression type
  63     int compression;
  64     // Flags
  65     int flags;
  66     // Decompressed data size
  67     unsigned int decomp_size;
  68     // Decompression buffer
  69     unsigned char* decomp_buf;
  70 #if CONFIG_ZLIB_DECODER
  71     z_stream zstream;
  72 #endif
  73 } LclDecContext;
  74
  75
  76 /**
  77  * @param srcptr compressed source buffer, must be padded with at least 5 extra bytes
  78  * @param destptr must be padded sufficiently for av_memcpy_backptr
  79  */
  80 static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsigned char * destptr, unsigned int destsize)
  81 {
  82     unsigned char *destptr_bak = destptr;
  83     unsigned char *destptr_end = destptr + destsize;
  84     const unsigned char *srcptr_end = srcptr + srclen;
  85     unsigned mask = *srcptr++;
  86     unsigned maskbit = 0x80;
  87
  88     while (srcptr < srcptr_end && destptr < destptr_end) {
  89         if (!(mask & maskbit)) {
  90             memcpy(destptr, srcptr, 4);
  91             destptr += 4;
  92             srcptr += 4;
  93         } else {
  94             unsigned ofs = bytestream_get_le16(&srcptr);
  95             unsigned cnt = (ofs >> 11) + 1;
  96             ofs &= 0x7ff;
  97             ofs = FFMIN(ofs, destptr - destptr_bak);
  98             cnt *= 4;
  99             cnt = FFMIN(cnt, destptr_end - destptr);
 100             av_memcpy_backptr(destptr, ofs, cnt);
 101             destptr += cnt;
 102         }
 103         maskbit >>= 1;
 104         if (!maskbit) {
 105             mask = *srcptr++;
 106             while (!mask) {
 107                 if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;
 108                 memcpy(destptr, srcptr, 32);
 109                 destptr += 32;
 110                 srcptr += 32;
 111                 mask = *srcptr++;
 112             }
 113             maskbit = 0x80;
 114         }
 115     }
 116
 117     return destptr - destptr_bak;
 118 }
 119
 120
 121 #if CONFIG_ZLIB_DECODER
 122 /**
 123  * @brief decompress a zlib-compressed data block into decomp_buf
 124  * @param src compressed input buffer
 125  * @param src_len data length in input buffer
 126  * @param offset offset in decomp_buf
 127  * @param expected expected decompressed length
 128  */
 129 static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)
 130 {
 131     LclDecContext *c = avctx->priv_data;
 132     int zret = inflateReset(&c->zstream);
 133     if (zret != Z_OK) {
 134         av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
 135         return AVERROR_UNKNOWN;
 136     }
 137     c->zstream.next_in = src;
 138     c->zstream.avail_in = src_len;
 139     c->zstream.next_out = c->decomp_buf + offset;
 140     c->zstream.avail_out = c->decomp_size - offset;
 141     zret = inflate(&c->zstream, Z_FINISH);
 142     if (zret != Z_OK && zret != Z_STREAM_END) {
 143         av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
 144         return AVERROR_UNKNOWN;
 145     }
 146     if (expected != (unsigned int)c->zstream.total_out) {
 147         av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %lu)\n",
 148                expected, c->zstream.total_out);
 149         return AVERROR_UNKNOWN;
 150     }
 151     return c->zstream.total_out;
 152 }
 153 #endif
 154
 155
 156 /*
 157  *
 158  * Decode a frame
 159  *
 160  */
 161 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
 162 {
 163     const uint8_t *buf = avpkt->data;
 164     int buf_size = avpkt->size;
 165     LclDecContext * const c = avctx->priv_data;
 166     unsigned char *encoded = (unsigned char *)buf;
 167     unsigned int pixel_ptr;
 168     int row, col;
 169     unsigned char *outptr;
 170     uint8_t *y_out, *u_out, *v_out;
 171     unsigned int width = avctx->width; // Real image width
 172     unsigned int height = avctx->height; // Real image height
 173     unsigned int mszh_dlen;
 174     unsigned char yq, y1q, uq, vq;
 175     int uqvq, ret;
 176     unsigned int mthread_inlen, mthread_outlen;
 177     unsigned int len = buf_size;
 178
 179     if(c->pic.data[0])
 180         avctx->release_buffer(avctx, &c->pic);
 181
 182     c->pic.reference = 0;
 183     c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
 184     if ((ret = ff_get_buffer(avctx, &c->pic)) < 0) {
 185         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 186         return ret;
 187     }
 188
 189     outptr = c->pic.data[0]; // Output image pointer
 190
 191     /* Decompress frame */
 192     switch (avctx->codec_id) {
 193     case AV_CODEC_ID_MSZH:
 194         switch (c->compression) {
 195         case COMP_MSZH:
 196             if (c->flags & FLAG_MULTITHREAD) {
 197                 mthread_inlen = AV_RL32(encoded);
 198                 mthread_inlen = FFMIN(mthread_inlen, len - 8);
 199                 mthread_outlen = AV_RL32(encoded+4);
 200                 mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
 201                 mszh_dlen = mszh_decomp(encoded + 8, mthread_inlen, c->decomp_buf, c->decomp_size);
 202                 if (mthread_outlen != mszh_dlen) {
 203                     av_log(avctx, AV_LOG_ERROR, "Mthread1 decoded size differs (%d != %d)\n",
 204                            mthread_outlen, mszh_dlen);
 205                     return AVERROR_INVALIDDATA;
 206                 }
 207                 mszh_dlen = mszh_decomp(encoded + 8 + mthread_inlen, len - 8 - mthread_inlen,
 208                                         c->decomp_buf + mthread_outlen, c->decomp_size - mthread_outlen);
 209                 if (mthread_outlen != mszh_dlen) {
 210                     av_log(avctx, AV_LOG_ERROR, "Mthread2 decoded size differs (%d != %d)\n",
 211                            mthread_outlen, mszh_dlen);
 212                     return AVERROR_INVALIDDATA;
 213                 }
 214                 encoded = c->decomp_buf;
 215                 len = c->decomp_size;
 216             } else {
 217                 mszh_dlen = mszh_decomp(encoded, len, c->decomp_buf, c->decomp_size);
 218                 if (c->decomp_size != mszh_dlen) {
 219                     av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %d)\n",
 220                            c->decomp_size, mszh_dlen);
 221                     return AVERROR_INVALIDDATA;
 222                 }
 223                 encoded = c->decomp_buf;
 224                 len = mszh_dlen;
 225             }
 226             break;
 227         case COMP_MSZH_NOCOMP: {
 228             int bppx2;
 229             switch (c->imgtype) {
 230             case IMGTYPE_YUV111:
 231             case IMGTYPE_RGB24:
 232                 bppx2 = 6;
 233                 break;
 234             case IMGTYPE_YUV422:
 235             case IMGTYPE_YUV211:
 236                 bppx2 = 4;
 237                 break;
 238             case IMGTYPE_YUV411:
 239             case IMGTYPE_YUV420:
 240                 bppx2 = 3;
 241                 break;
 242             default:
 243                 bppx2 = 0; // will error out below
 244                 break;
 245             }
 246             if (len < ((width * height * bppx2) >> 1))
 247                 return AVERROR_INVALIDDATA;
 248             break;
 249         }
 250         default:
 251             av_log(avctx, AV_LOG_ERROR, "BUG! Unknown MSZH compression in frame decoder.\n");
 252             return AVERROR_INVALIDDATA;
 253         }
 254         break;
 255 #if CONFIG_ZLIB_DECODER
 256     case AV_CODEC_ID_ZLIB:
 257         /* Using the original dll with normal compression (-1) and RGB format
 258          * gives a file with ZLIB fourcc, but frame is really uncompressed.
 259          * To be sure that's true check also frame size */
 260         if (c->compression == COMP_ZLIB_NORMAL && c->imgtype == IMGTYPE_RGB24 &&
 261             len == width * height * 3) {
 262             if (c->flags & FLAG_PNGFILTER) {
 263                 memcpy(c->decomp_buf, encoded, len);
 264                 encoded = c->decomp_buf;
 265             } else {
 266                 break;
 267             }
 268         } else if (c->flags & FLAG_MULTITHREAD) {
 269             mthread_inlen = AV_RL32(encoded);
 270             mthread_inlen = FFMIN(mthread_inlen, len - 8);
 271             mthread_outlen = AV_RL32(encoded+4);
 272             mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
 273             ret = zlib_decomp(avctx, encoded + 8, mthread_inlen, 0, mthread_outlen);
 274             if (ret < 0) return ret;
 275             ret = zlib_decomp(avctx, encoded + 8 + mthread_inlen, len - 8 - mthread_inlen,
 276                               mthread_outlen, mthread_outlen);
 277             if (ret < 0) return ret;
 278         } else {
 279             int ret = zlib_decomp(avctx, encoded, len, 0, c->decomp_size);
 280             if (ret < 0) return ret;
 281         }
 282         encoded = c->decomp_buf;
 283         len = c->decomp_size;
 284         break;
 285 #endif
 286     default:
 287         av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in frame decoder compression switch.\n");
 288         return AVERROR_INVALIDDATA;
 289     }
 290
 291
 292     /* Apply PNG filter */
 293     if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER)) {
 294         switch (c->imgtype) {
 295         case IMGTYPE_YUV111:
 296         case IMGTYPE_RGB24:
 297             for (row = 0; row < height; row++) {
 298                 pixel_ptr = row * width * 3;
 299                 yq = encoded[pixel_ptr++];
 300                 uqvq = AV_RL16(encoded+pixel_ptr);
 301                 pixel_ptr += 2;
 302                 for (col = 1; col < width; col++) {
 303                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
 304                     uqvq -= AV_RL16(encoded+pixel_ptr+1);
 305                     AV_WL16(encoded+pixel_ptr+1, uqvq);
 306                     pixel_ptr += 3;
 307                 }
 308             }
 309             break;
 310         case IMGTYPE_YUV422:
 311             for (row = 0; row < height; row++) {
 312                 pixel_ptr = row * width * 2;
 313                 yq = uq = vq =0;
 314                 for (col = 0; col < width/4; col++) {
 315                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
 316                     encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
 317                     encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
 318                     encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
 319                     encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
 320                     encoded[pixel_ptr+5] = uq -= encoded[pixel_ptr+5];
 321                     encoded[pixel_ptr+6] = vq -= encoded[pixel_ptr+6];
 322                     encoded[pixel_ptr+7] = vq -= encoded[pixel_ptr+7];
 323                     pixel_ptr += 8;
 324                 }
 325             }
 326             break;
 327         case IMGTYPE_YUV411:
 328             for (row = 0; row < height; row++) {
 329                 pixel_ptr = row * width / 2 * 3;
 330                 yq = uq = vq =0;
 331                 for (col = 0; col < width/4; col++) {
 332                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
 333                     encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
 334                     encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
 335                     encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
 336                     encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
 337                     encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
 338                     pixel_ptr += 6;
 339                 }
 340             }
 341             break;
 342         case IMGTYPE_YUV211:
 343             for (row = 0; row < height; row++) {
 344                 pixel_ptr = row * width * 2;
 345                 yq = uq = vq =0;
 346                 for (col = 0; col < width/2; col++) {
 347                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
 348                     encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
 349                     encoded[pixel_ptr+2] = uq -= encoded[pixel_ptr+2];
 350                     encoded[pixel_ptr+3] = vq -= encoded[pixel_ptr+3];
 351                     pixel_ptr += 4;
 352                 }
 353             }
 354             break;
 355         case IMGTYPE_YUV420:
 356             for (row = 0; row < height/2; row++) {
 357                 pixel_ptr = row * width * 3;
 358                 yq = y1q = uq = vq =0;
 359                 for (col = 0; col < width/2; col++) {
 360                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
 361                     encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
 362                     encoded[pixel_ptr+2] = y1q -= encoded[pixel_ptr+2];
 363                     encoded[pixel_ptr+3] = y1q -= encoded[pixel_ptr+3];
 364                     encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
 365                     encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
 366                     pixel_ptr += 6;
 367                 }
 368             }
 369             break;
 370         default:
 371             av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in pngfilter switch.\n");
 372             return AVERROR_INVALIDDATA;
 373         }
 374     }
 375
 376     /* Convert colorspace */
 377     y_out = c->pic.data[0] + (height - 1) * c->pic.linesize[0];
 378     u_out = c->pic.data[1] + (height - 1) * c->pic.linesize[1];
 379     v_out = c->pic.data[2] + (height - 1) * c->pic.linesize[2];
 380     switch (c->imgtype) {
 381     case IMGTYPE_YUV111:
 382         for (row = 0; row < height; row++) {
 383             for (col = 0; col < width; col++) {
 384                 y_out[col] = *encoded++;
 385                 u_out[col] = *encoded++ + 128;
 386                 v_out[col] = *encoded++ + 128;
 387             }
 388             y_out -= c->pic.linesize[0];
 389             u_out -= c->pic.linesize[1];
 390             v_out -= c->pic.linesize[2];
 391         }
 392         break;
 393     case IMGTYPE_YUV422:
 394         for (row = 0; row < height; row++) {
 395             for (col = 0; col < width - 3; col += 4) {
 396                 memcpy(y_out + col, encoded, 4);
 397                 encoded += 4;
 398                 u_out[ col >> 1     ] = *encoded++ + 128;
 399                 u_out[(col >> 1) + 1] = *encoded++ + 128;
 400                 v_out[ col >> 1     ] = *encoded++ + 128;
 401                 v_out[(col >> 1) + 1] = *encoded++ + 128;
 402             }
 403             y_out -= c->pic.linesize[0];
 404             u_out -= c->pic.linesize[1];
 405             v_out -= c->pic.linesize[2];
 406         }
 407         break;
 408     case IMGTYPE_RGB24:
 409         for (row = height - 1; row >= 0; row--) {
 410             pixel_ptr = row * c->pic.linesize[0];
 411             memcpy(outptr + pixel_ptr, encoded, 3 * width);
 412             encoded += 3 * width;
 413         }
 414         break;
 415     case IMGTYPE_YUV411:
 416         for (row = 0; row < height; row++) {
 417             for (col = 0; col < width - 3; col += 4) {
 418                 memcpy(y_out + col, encoded, 4);
 419                 encoded += 4;
 420                 u_out[col >> 2] = *encoded++ + 128;
 421                 v_out[col >> 2] = *encoded++ + 128;
 422             }
 423             y_out -= c->pic.linesize[0];
 424             u_out -= c->pic.linesize[1];
 425             v_out -= c->pic.linesize[2];
 426         }
 427         break;
 428     case IMGTYPE_YUV211:
 429         for (row = 0; row < height; row++) {
 430             for (col = 0; col < width - 1; col += 2) {
 431                 memcpy(y_out + col, encoded, 2);
 432                 encoded += 2;
 433                 u_out[col >> 1] = *encoded++ + 128;
 434                 v_out[col >> 1] = *encoded++ + 128;
 435             }
 436             y_out -= c->pic.linesize[0];
 437             u_out -= c->pic.linesize[1];
 438             v_out -= c->pic.linesize[2];
 439         }
 440         break;
 441     case IMGTYPE_YUV420:
 442         u_out = c->pic.data[1] + ((height >> 1) - 1) * c->pic.linesize[1];
 443         v_out = c->pic.data[2] + ((height >> 1) - 1) * c->pic.linesize[2];
 444         for (row = 0; row < height - 1; row += 2) {
 445             for (col = 0; col < width - 1; col += 2) {
 446                 memcpy(y_out + col, encoded, 2);
 447                 encoded += 2;
 448                 memcpy(y_out + col - c->pic.linesize[0], encoded, 2);
 449                 encoded += 2;
 450                 u_out[col >> 1] = *encoded++ + 128;
 451                 v_out[col >> 1] = *encoded++ + 128;
 452             }
 453             y_out -= c->pic.linesize[0] << 1;
 454             u_out -= c->pic.linesize[1];
 455             v_out -= c->pic.linesize[2];
 456         }
 457         break;
 458     default:
 459         av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in image decoder.\n");
 460         return AVERROR_INVALIDDATA;
 461     }
 462
 463     *got_frame = 1;
 464     *(AVFrame*)data = c->pic;
 465
 466     /* always report that the buffer was completely consumed */
 467     return buf_size;
 468 }
 469
 470 /*
 471  *
 472  * Init lcl decoder
 473  *
 474  */
 475 static av_cold int decode_init(AVCodecContext *avctx)
 476 {
 477     LclDecContext * const c = avctx->priv_data;
 478     unsigned int basesize = avctx->width * avctx->height;
 479     unsigned int max_basesize = FFALIGN(avctx->width,  4) *
 480                                 FFALIGN(avctx->height, 4);
 481     unsigned int max_decomp_size;
 482
 483     if (avctx->extradata_size < 8) {
 484         av_log(avctx, AV_LOG_ERROR, "Extradata size too small.\n");
 485         return AVERROR_INVALIDDATA;
 486     }
 487
 488     /* Check codec type */
 489     if ((avctx->codec_id == AV_CODEC_ID_MSZH  && avctx->extradata[7] != CODEC_MSZH) ||
 490         (avctx->codec_id == AV_CODEC_ID_ZLIB  && avctx->extradata[7] != CODEC_ZLIB)) {
 491         av_log(avctx, AV_LOG_ERROR, "Codec id and codec type mismatch. This should not happen.\n");
 492     }
 493
 494     /* Detect image type */
 495     switch (c->imgtype = avctx->extradata[4]) {
 496     case IMGTYPE_YUV111:
 497         c->decomp_size = basesize * 3;
 498         max_decomp_size = max_basesize * 3;
 499         avctx->pix_fmt = AV_PIX_FMT_YUV444P;
 500         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 1:1:1.\n");
 501         break;
 502     case IMGTYPE_YUV422:
 503         c->decomp_size = basesize * 2;
 504         max_decomp_size = max_basesize * 2;
 505         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
 506         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:2.\n");
 507         break;
 508     case IMGTYPE_RGB24:
 509         c->decomp_size = basesize * 3;
 510         max_decomp_size = max_basesize * 3;
 511         avctx->pix_fmt = AV_PIX_FMT_BGR24;
 512         av_log(avctx, AV_LOG_DEBUG, "Image type is RGB 24.\n");
 513         break;
 514     case IMGTYPE_YUV411:
 515         c->decomp_size = basesize / 2 * 3;
 516         max_decomp_size = max_basesize / 2 * 3;
 517         avctx->pix_fmt = AV_PIX_FMT_YUV411P;
 518         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:1:1.\n");
 519         break;
 520     case IMGTYPE_YUV211:
 521         c->decomp_size = basesize * 2;
 522         max_decomp_size = max_basesize * 2;
 523         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
 524         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 2:1:1.\n");
 525         break;
 526     case IMGTYPE_YUV420:
 527         c->decomp_size = basesize / 2 * 3;
 528         max_decomp_size = max_basesize / 2 * 3;
 529         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
 530         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:0.\n");
 531         break;
 532     default:
 533         av_log(avctx, AV_LOG_ERROR, "Unsupported image format %d.\n", c->imgtype);
 534         return AVERROR_INVALIDDATA;
 535     }
 536
 537     /* Detect compression method */
 538     c->compression = (int8_t)avctx->extradata[5];
 539     switch (avctx->codec_id) {
 540     case AV_CODEC_ID_MSZH:
 541         switch (c->compression) {
 542         case COMP_MSZH:
 543             av_log(avctx, AV_LOG_DEBUG, "Compression enabled.\n");
 544             break;
 545         case COMP_MSZH_NOCOMP:
 546             c->decomp_size = 0;
 547             av_log(avctx, AV_LOG_DEBUG, "No compression.\n");
 548             break;
 549         default:
 550             av_log(avctx, AV_LOG_ERROR, "Unsupported compression format for MSZH (%d).\n", c->compression);
 551             return AVERROR_INVALIDDATA;
 552         }
 553         break;
 554 #if CONFIG_ZLIB_DECODER
 555     case AV_CODEC_ID_ZLIB:
 556         switch (c->compression) {
 557         case COMP_ZLIB_HISPEED:
 558             av_log(avctx, AV_LOG_DEBUG, "High speed compression.\n");
 559             break;
 560         case COMP_ZLIB_HICOMP:
 561             av_log(avctx, AV_LOG_DEBUG, "High compression.\n");
 562             break;
 563         case COMP_ZLIB_NORMAL:
 564             av_log(avctx, AV_LOG_DEBUG, "Normal compression.\n");
 565             break;
 566         default:
 567             if (c->compression < Z_NO_COMPRESSION || c->compression > Z_BEST_COMPRESSION) {
 568                 av_log(avctx, AV_LOG_ERROR, "Unsupported compression level for ZLIB: (%d).\n", c->compression);
 569                 return AVERROR_INVALIDDATA;
 570             }
 571             av_log(avctx, AV_LOG_DEBUG, "Compression level for ZLIB: (%d).\n", c->compression);
 572         }
 573         break;
 574 #endif
 575     default:
 576         av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in compression switch.\n");
 577         return AVERROR_INVALIDDATA;
 578     }
 579
 580     /* Allocate decompression buffer */
 581     if (c->decomp_size) {
 582         if ((c->decomp_buf = av_malloc(max_decomp_size)) == NULL) {
 583             av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
 584             return AVERROR(ENOMEM);
 585         }
 586     }
 587
 588     /* Detect flags */
 589     c->flags = avctx->extradata[6];
 590     if (c->flags & FLAG_MULTITHREAD)
 591         av_log(avctx, AV_LOG_DEBUG, "Multithread encoder flag set.\n");
 592     if (c->flags & FLAG_NULLFRAME)
 593         av_log(avctx, AV_LOG_DEBUG, "Nullframe insertion flag set.\n");
 594     if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER))
 595         av_log(avctx, AV_LOG_DEBUG, "PNG filter flag set.\n");
 596     if (c->flags & FLAGMASK_UNUSED)
 597         av_log(avctx, AV_LOG_ERROR, "Unknown flag set (%d).\n", c->flags);
 598
 599     /* If needed init zlib */
 600 #if CONFIG_ZLIB_DECODER
 601     if (avctx->codec_id == AV_CODEC_ID_ZLIB) {
 602         int zret;
 603         c->zstream.zalloc = Z_NULL;
 604         c->zstream.zfree = Z_NULL;
 605         c->zstream.opaque = Z_NULL;
 606         zret = inflateInit(&c->zstream);
 607         if (zret != Z_OK) {
 608             av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
 609             av_freep(&c->decomp_buf);
 610             return AVERROR_UNKNOWN;
 611         }
 612     }
 613 #endif
 614
 615     return 0;
 616 }
 617
 618 /*
 619  *
 620  * Uninit lcl decoder
 621  *
 622  */
 623 static av_cold int decode_end(AVCodecContext *avctx)
 624 {
 625     LclDecContext * const c = avctx->priv_data;
 626
 627     av_freep(&c->decomp_buf);
 628     if (c->pic.data[0])
 629         avctx->release_buffer(avctx, &c->pic);
 630 #if CONFIG_ZLIB_DECODER
 631     if (avctx->codec_id == AV_CODEC_ID_ZLIB)
 632         inflateEnd(&c->zstream);
 633 #endif
 634
 635     return 0;
 636 }
 637
 638 #if CONFIG_MSZH_DECODER
 639 AVCodec ff_mszh_decoder = {
 640     .name           = "mszh",
 641     .type           = AVMEDIA_TYPE_VIDEO,
 642     .id             = AV_CODEC_ID_MSZH,
 643     .priv_data_size = sizeof(LclDecContext),
 644     .init           = decode_init,
 645     .close          = decode_end,
 646     .decode         = decode_frame,
 647     .capabilities   = CODEC_CAP_DR1,
 648     .long_name      = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) MSZH"),
 649 };
 650 #endif
 651
 652 #if CONFIG_ZLIB_DECODER
 653 AVCodec ff_zlib_decoder = {
 654     .name           = "zlib",
 655     .type           = AVMEDIA_TYPE_VIDEO,
 656     .id             = AV_CODEC_ID_ZLIB,
 657     .priv_data_size = sizeof(LclDecContext),
 658     .init           = decode_init,
 659     .close          = decode_end,
 660     .decode         = decode_frame,
 661     .capabilities   = CODEC_CAP_DR1,
 662     .long_name      = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
 663 };
 664 #endif