1 /*
2  * LCL (LossLess Codec Library) Codec
3  * Copyright (c) 2002-2004 Roberto Togni
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 #include "config_components.h"
41 
42 #include <stdio.h>
43 #include <stdlib.h>
44 
45 #include "libavutil/mem.h"
46 #include "libavutil/pixdesc.h"
47 #include "avcodec.h"
48 #include "bytestream.h"
49 #include "codec_internal.h"
50 #include "lcl.h"
51 #include "thread.h"
52 
53 #if CONFIG_ZLIB_DECODER
54 #include "zlib_wrapper.h"
55 #include <zlib.h>
56 #endif
57 
58 typedef struct LclDecContext {
59     // Image type
60     int imgtype;
61     // Compression type
62     int compression;
63     // Flags
64     int flags;
65     // Decompressed data size
66     unsigned int decomp_size;
67     // Decompression buffer
68     unsigned char* decomp_buf;
69 #if CONFIG_ZLIB_DECODER
70     FFZStream zstream;
71 #endif
72 } LclDecContext;
73 
74 
75 /**
76  * @param srcptr compressed source buffer, must be padded with at least 5 extra bytes
77  * @param destptr must be padded sufficiently for av_memcpy_backptr
78  */
mszh_decomp(const unsigned char * srcptr, int srclen, unsigned char * destptr, unsigned int destsize)79 static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsigned char * destptr, unsigned int destsize)
80 {
81     unsigned char *destptr_bak = destptr;
82     unsigned char *destptr_end = destptr + destsize;
83     const unsigned char *srcptr_end = srcptr + srclen;
84     unsigned mask = *srcptr++;
85     unsigned maskbit = 0x80;
86 
87     while (srcptr < srcptr_end && destptr < destptr_end) {
88         if (!(mask & maskbit)) {
89             memcpy(destptr, srcptr, 4);
90             destptr += 4;
91             srcptr += 4;
92         } else {
93             unsigned ofs = bytestream_get_le16(&srcptr);
94             unsigned cnt = (ofs >> 11) + 1;
95             ofs &= 0x7ff;
96             ofs = FFMIN(ofs, destptr - destptr_bak);
97             cnt *= 4;
98             cnt = FFMIN(cnt, destptr_end - destptr);
99             if (ofs) {
100                 av_memcpy_backptr(destptr, ofs, cnt);
101             } else {
102                 // Not known what the correct behaviour is, but
103                 // this at least avoids uninitialized data.
104                 memset(destptr, 0, cnt);
105             }
106             destptr += cnt;
107         }
108         maskbit >>= 1;
109         if (!maskbit) {
110             mask = *srcptr++;
111             while (!mask) {
112                 if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;
113                 memcpy(destptr, srcptr, 32);
114                 destptr += 32;
115                 srcptr += 32;
116                 mask = *srcptr++;
117             }
118             maskbit = 0x80;
119         }
120     }
121 
122     return destptr - destptr_bak;
123 }
124 
125 
126 #if CONFIG_ZLIB_DECODER
127 /**
128  * @brief decompress a zlib-compressed data block into decomp_buf
129  * @param src compressed input buffer
130  * @param src_len data length in input buffer
131  * @param offset offset in decomp_buf
132  * @param expected expected decompressed length
133  */
zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)134 static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)
135 {
136     LclDecContext *c = avctx->priv_data;
137     z_stream *const zstream = &c->zstream.zstream;
138     int zret = inflateReset(zstream);
139     if (zret != Z_OK) {
140         av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
141         return AVERROR_UNKNOWN;
142     }
143     zstream->next_in   = src;
144     zstream->avail_in  = src_len;
145     zstream->next_out  = c->decomp_buf + offset;
146     zstream->avail_out = c->decomp_size - offset;
147     zret = inflate(zstream, Z_FINISH);
148     if (zret != Z_OK && zret != Z_STREAM_END) {
149         av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
150         return AVERROR_UNKNOWN;
151     }
152     if (expected != (unsigned int)zstream->total_out) {
153         av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %lu)\n",
154                expected, zstream->total_out);
155         if (expected > (unsigned int)zstream->total_out)
156             return (unsigned int)zstream->total_out;
157         return AVERROR_UNKNOWN;
158     }
159     return zstream->total_out;
160 }
161 #endif
162 
163 
decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)164 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
165                         int *got_frame, AVPacket *avpkt)
166 {
167     const uint8_t *buf = avpkt->data;
168     int buf_size = avpkt->size;
169     LclDecContext * const c = avctx->priv_data;
170     unsigned int pixel_ptr;
171     int row, col;
172     unsigned char *encoded = avpkt->data, *outptr;
173     uint8_t *y_out, *u_out, *v_out;
174     int width = avctx->width; // Real image width
175     int height = avctx->height; // Real image height
176     unsigned int mszh_dlen;
177     unsigned char yq, y1q, uq, vq;
178     int uqvq, ret;
179     unsigned int mthread_inlen, mthread_outlen;
180     unsigned int len = buf_size;
181     int linesize, offset;
182 
183     if ((ret = ff_thread_get_buffer(avctx, frame, 0)) < 0)
184         return ret;
185 
186     outptr = frame->data[0]; // Output image pointer
187 
188     /* Decompress frame */
189     switch (avctx->codec_id) {
190     case AV_CODEC_ID_MSZH:
191         switch (c->compression) {
192         case COMP_MSZH:
193             if (c->imgtype == IMGTYPE_RGB24 && len == FFALIGN(width * 3, 4) * height ||
194                 c->imgtype == IMGTYPE_YUV111 && len == width * height * 3) {
195                 ;
196             } else if (c->flags & FLAG_MULTITHREAD) {
197                 mthread_inlen = AV_RL32(buf);
198                 if (len < 8 || len - 8 < mthread_inlen) {
199                     av_log(avctx, AV_LOG_ERROR, "len %d is too small\n", len);
200                     return AVERROR_INVALIDDATA;
201                 }
202                 mthread_outlen = AV_RL32(buf + 4);
203                 mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
204                 mszh_dlen = mszh_decomp(buf + 8, mthread_inlen, c->decomp_buf, c->decomp_size);
205                 if (mthread_outlen != mszh_dlen) {
206                     av_log(avctx, AV_LOG_ERROR, "Mthread1 decoded size differs (%d != %d)\n",
207                            mthread_outlen, mszh_dlen);
208                     return AVERROR_INVALIDDATA;
209                 }
210                 mszh_dlen = mszh_decomp(buf + 8 + mthread_inlen, len - 8 - mthread_inlen,
211                                         c->decomp_buf + mthread_outlen, c->decomp_size - mthread_outlen);
212                 if (mthread_outlen != mszh_dlen) {
213                     av_log(avctx, AV_LOG_ERROR, "Mthread2 decoded size differs (%d != %d)\n",
214                            mthread_outlen, mszh_dlen);
215                     return AVERROR_INVALIDDATA;
216                 }
217                 encoded = c->decomp_buf;
218                 len = c->decomp_size;
219             } else {
220                 mszh_dlen = mszh_decomp(buf, len, c->decomp_buf, c->decomp_size);
221                 if (c->decomp_size != mszh_dlen) {
222                     av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %d)\n",
223                            c->decomp_size, mszh_dlen);
224                     return AVERROR_INVALIDDATA;
225                 }
226                 encoded = c->decomp_buf;
227                 len = mszh_dlen;
228             }
229             break;
230         case COMP_MSZH_NOCOMP: {
231             int bppx2;
232             int aligned_width = width;
233             switch (c->imgtype) {
234             case IMGTYPE_YUV111:
235             case IMGTYPE_RGB24:
236                 bppx2 = 6;
237                 break;
238             case IMGTYPE_YUV422:
239                 aligned_width &= ~3;
240             case IMGTYPE_YUV211:
241                 bppx2 = 4;
242                 break;
243             case IMGTYPE_YUV411:
244                 aligned_width &= ~3;
245             case IMGTYPE_YUV420:
246                 bppx2 = 3;
247                 break;
248             default:
249                 bppx2 = 0; // will error out below
250                 break;
251             }
252             if (len < ((aligned_width * height * bppx2) >> 1))
253                 return AVERROR_INVALIDDATA;
254             break;
255         }
256         default:
257             av_log(avctx, AV_LOG_ERROR, "BUG! Unknown MSZH compression in frame decoder.\n");
258             return AVERROR_INVALIDDATA;
259         }
260         break;
261 #if CONFIG_ZLIB_DECODER
262     case AV_CODEC_ID_ZLIB:
263         /* Using the original dll with normal compression (-1) and RGB format
264          * gives a file with ZLIB fourcc, but frame is really uncompressed.
265          * To be sure that's true check also frame size */
266         if (c->compression == COMP_ZLIB_NORMAL && c->imgtype == IMGTYPE_RGB24 &&
267             len == width * height * 3) {
268             if (c->flags & FLAG_PNGFILTER) {
269                 memcpy(c->decomp_buf, buf, len);
270                 encoded = c->decomp_buf;
271             } else {
272                 break;
273             }
274         } else if (c->flags & FLAG_MULTITHREAD) {
275             mthread_inlen = AV_RL32(buf);
276             mthread_inlen = FFMIN(mthread_inlen, len - 8);
277             mthread_outlen = AV_RL32(buf + 4);
278             mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
279             ret = zlib_decomp(avctx, buf + 8, mthread_inlen, 0, mthread_outlen);
280             if (ret < 0) return ret;
281             ret = zlib_decomp(avctx, buf + 8 + mthread_inlen, len - 8 - mthread_inlen,
282                               mthread_outlen, mthread_outlen);
283             if (ret < 0) return ret;
284             len = c->decomp_size;
285         } else {
286             int ret = zlib_decomp(avctx, buf, len, 0, c->decomp_size);
287             if (ret < 0) return ret;
288             len = ret;
289         }
290         encoded = c->decomp_buf;
291         break;
292 #endif
293     default:
294         av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in frame decoder compression switch.\n");
295         return AVERROR_INVALIDDATA;
296     }
297 
298 
299     /* Apply PNG filter */
300     if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER)) {
301         switch (c->imgtype) {
302         case IMGTYPE_YUV111:
303         case IMGTYPE_RGB24:
304             for (row = 0; row < height; row++) {
305                 pixel_ptr = row * width * 3;
306                 yq = encoded[pixel_ptr++];
307                 uqvq = AV_RL16(encoded+pixel_ptr);
308                 pixel_ptr += 2;
309                 for (col = 1; col < width; col++) {
310                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
311                     uqvq -= AV_RL16(encoded+pixel_ptr+1);
312                     AV_WL16(encoded+pixel_ptr+1, uqvq);
313                     pixel_ptr += 3;
314                 }
315             }
316             break;
317         case IMGTYPE_YUV422:
318             pixel_ptr = 0;
319             for (row = 0; row < height; row++) {
320                 yq = uq = vq =0;
321                 for (col = 0; col < width/4; col++) {
322                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
323                     encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
324                     encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
325                     encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
326                     encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
327                     encoded[pixel_ptr+5] = uq -= encoded[pixel_ptr+5];
328                     encoded[pixel_ptr+6] = vq -= encoded[pixel_ptr+6];
329                     encoded[pixel_ptr+7] = vq -= encoded[pixel_ptr+7];
330                     pixel_ptr += 8;
331                 }
332             }
333             break;
334         case IMGTYPE_YUV411:
335             pixel_ptr = 0;
336             for (row = 0; row < height; row++) {
337                 yq = uq = vq =0;
338                 for (col = 0; col < width/4; col++) {
339                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
340                     encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
341                     encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
342                     encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
343                     encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
344                     encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
345                     pixel_ptr += 6;
346                 }
347             }
348             break;
349         case IMGTYPE_YUV211:
350             for (row = 0; row < height; row++) {
351                 pixel_ptr = row * width * 2;
352                 yq = uq = vq =0;
353                 for (col = 0; col < width/2; col++) {
354                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
355                     encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
356                     encoded[pixel_ptr+2] = uq -= encoded[pixel_ptr+2];
357                     encoded[pixel_ptr+3] = vq -= encoded[pixel_ptr+3];
358                     pixel_ptr += 4;
359                 }
360             }
361             break;
362         case IMGTYPE_YUV420:
363             for (row = 0; row < height/2; row++) {
364                 pixel_ptr = row * width * 3;
365                 yq = y1q = uq = vq =0;
366                 for (col = 0; col < width/2; col++) {
367                     encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
368                     encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
369                     encoded[pixel_ptr+2] = y1q -= encoded[pixel_ptr+2];
370                     encoded[pixel_ptr+3] = y1q -= encoded[pixel_ptr+3];
371                     encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
372                     encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
373                     pixel_ptr += 6;
374                 }
375             }
376             break;
377         default:
378             av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in pngfilter switch.\n");
379             return AVERROR_INVALIDDATA;
380         }
381     }
382 
383     /* Convert colorspace */
384     y_out = frame->data[0] + (height - 1) * frame->linesize[0];
385     offset = (height - 1) * frame->linesize[1];
386     u_out = FF_PTR_ADD(frame->data[1], offset);
387     offset = (height - 1) * frame->linesize[2];
388     v_out = FF_PTR_ADD(frame->data[2], offset);
389     switch (c->imgtype) {
390     case IMGTYPE_YUV111:
391         for (row = 0; row < height; row++) {
392             for (col = 0; col < width; col++) {
393                 y_out[col] = *encoded++;
394                 u_out[col] = *encoded++ + 128;
395                 v_out[col] = *encoded++ + 128;
396             }
397             y_out -= frame->linesize[0];
398             u_out -= frame->linesize[1];
399             v_out -= frame->linesize[2];
400         }
401         break;
402     case IMGTYPE_YUV422:
403         for (row = 0; row < height; row++) {
404             for (col = 0; col < width - 3; col += 4) {
405                 memcpy(y_out + col, encoded, 4);
406                 encoded += 4;
407                 u_out[ col >> 1     ] = *encoded++ + 128;
408                 u_out[(col >> 1) + 1] = *encoded++ + 128;
409                 v_out[ col >> 1     ] = *encoded++ + 128;
410                 v_out[(col >> 1) + 1] = *encoded++ + 128;
411             }
412             if (col && col < width) {
413                 u_out[ col >> 1     ] = u_out[(col>>1) - 1];
414                 v_out[ col >> 1     ] = v_out[(col>>1) - 1];
415             }
416 
417             y_out -= frame->linesize[0];
418             u_out -= frame->linesize[1];
419             v_out -= frame->linesize[2];
420         }
421         break;
422     case IMGTYPE_RGB24:
423         linesize = len < FFALIGN(3 * width, 4) * height ? 3 * width : FFALIGN(3 * width, 4);
424         for (row = height - 1; row >= 0; row--) {
425             pixel_ptr = row * frame->linesize[0];
426             memcpy(outptr + pixel_ptr, encoded, 3 * width);
427             encoded += linesize;
428         }
429         break;
430     case IMGTYPE_YUV411:
431         for (row = 0; row < height; row++) {
432             for (col = 0; col < width - 3; col += 4) {
433                 memcpy(y_out + col, encoded, 4);
434                 encoded += 4;
435                 u_out[col >> 2] = *encoded++ + 128;
436                 v_out[col >> 2] = *encoded++ + 128;
437             }
438             if (col && col < width) {
439                 u_out[col >> 2] = u_out[(col>>2) - 1];
440                 v_out[col >> 2] = v_out[(col>>2) - 1];
441             }
442             y_out -= frame->linesize[0];
443             u_out -= frame->linesize[1];
444             v_out -= frame->linesize[2];
445         }
446         break;
447     case IMGTYPE_YUV211:
448         for (row = 0; row < height; row++) {
449             for (col = 0; col < width - 1; col += 2) {
450                 memcpy(y_out + col, encoded, 2);
451                 encoded += 2;
452                 u_out[col >> 1] = *encoded++ + 128;
453                 v_out[col >> 1] = *encoded++ + 128;
454             }
455             y_out -= frame->linesize[0];
456             u_out -= frame->linesize[1];
457             v_out -= frame->linesize[2];
458         }
459         break;
460     case IMGTYPE_YUV420:
461         u_out = frame->data[1] + ((height >> 1) - 1) * frame->linesize[1];
462         v_out = frame->data[2] + ((height >> 1) - 1) * frame->linesize[2];
463         for (row = 0; row < height - 1; row += 2) {
464             for (col = 0; col < width - 1; col += 2) {
465                 memcpy(y_out + col, encoded, 2);
466                 encoded += 2;
467                 memcpy(y_out + col - frame->linesize[0], encoded, 2);
468                 encoded += 2;
469                 u_out[col >> 1] = *encoded++ + 128;
470                 v_out[col >> 1] = *encoded++ + 128;
471             }
472             y_out -= frame->linesize[0] << 1;
473             u_out -= frame->linesize[1];
474             v_out -= frame->linesize[2];
475         }
476         break;
477     default:
478         av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in image decoder.\n");
479         return AVERROR_INVALIDDATA;
480     }
481 
482     frame->key_frame = 1;
483     frame->pict_type = AV_PICTURE_TYPE_I;
484 
485     *got_frame = 1;
486 
487     /* always report that the buffer was completely consumed */
488     return buf_size;
489 }
490 
decode_init(AVCodecContext *avctx)491 static av_cold int decode_init(AVCodecContext *avctx)
492 {
493     LclDecContext * const c = avctx->priv_data;
494     unsigned int basesize = avctx->width * avctx->height;
495     unsigned int max_basesize = FFALIGN(avctx->width,  4) *
496                                 FFALIGN(avctx->height, 4);
497     unsigned int max_decomp_size;
498     int subsample_h, subsample_v;
499     int partial_h_supported = 0;
500 
501     if (avctx->extradata_size < 8) {
502         av_log(avctx, AV_LOG_ERROR, "Extradata size too small.\n");
503         return AVERROR_INVALIDDATA;
504     }
505 
506     /* Check codec type */
507     if ((avctx->codec_id == AV_CODEC_ID_MSZH  && avctx->extradata[7] != CODEC_MSZH) ||
508         (avctx->codec_id == AV_CODEC_ID_ZLIB  && avctx->extradata[7] != CODEC_ZLIB)) {
509         av_log(avctx, AV_LOG_ERROR, "Codec id and codec type mismatch. This should not happen.\n");
510     }
511 
512     /* Detect image type */
513     switch (c->imgtype = avctx->extradata[4]) {
514     case IMGTYPE_YUV111:
515         c->decomp_size = basesize * 3;
516         max_decomp_size = max_basesize * 3;
517         avctx->pix_fmt = AV_PIX_FMT_YUV444P;
518         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 1:1:1.\n");
519         break;
520     case IMGTYPE_YUV422:
521         c->decomp_size = (avctx->width & ~3) * avctx->height * 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 4:2:2.\n");
525         partial_h_supported = 1;
526         break;
527     case IMGTYPE_RGB24:
528         c->decomp_size = FFALIGN(avctx->width*3, 4) * avctx->height;
529         max_decomp_size = max_basesize * 3;
530         avctx->pix_fmt = AV_PIX_FMT_BGR24;
531         av_log(avctx, AV_LOG_DEBUG, "Image type is RGB 24.\n");
532         break;
533     case IMGTYPE_YUV411:
534         c->decomp_size = (avctx->width & ~3) * avctx->height / 2 * 3;
535         max_decomp_size = max_basesize / 2 * 3;
536         avctx->pix_fmt = AV_PIX_FMT_YUV411P;
537         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:1:1.\n");
538         partial_h_supported = 1;
539         break;
540     case IMGTYPE_YUV211:
541         c->decomp_size = basesize * 2;
542         max_decomp_size = max_basesize * 2;
543         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
544         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 2:1:1.\n");
545         break;
546     case IMGTYPE_YUV420:
547         c->decomp_size = basesize / 2 * 3;
548         max_decomp_size = max_basesize / 2 * 3;
549         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
550         av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:0.\n");
551         break;
552     default:
553         av_log(avctx, AV_LOG_ERROR, "Unsupported image format %d.\n", c->imgtype);
554         return AVERROR_INVALIDDATA;
555     }
556 
557     av_pix_fmt_get_chroma_sub_sample(avctx->pix_fmt, &subsample_h, &subsample_v);
558     if ((avctx->width % (1<<subsample_h) && !partial_h_supported) || avctx->height % (1<<subsample_v)) {
559         avpriv_request_sample(avctx, "Unsupported dimensions");
560         return AVERROR_INVALIDDATA;
561     }
562 
563     /* Detect compression method */
564     c->compression = (int8_t)avctx->extradata[5];
565     switch (avctx->codec_id) {
566     case AV_CODEC_ID_MSZH:
567         switch (c->compression) {
568         case COMP_MSZH:
569             av_log(avctx, AV_LOG_DEBUG, "Compression enabled.\n");
570             break;
571         case COMP_MSZH_NOCOMP:
572             c->decomp_size = 0;
573             av_log(avctx, AV_LOG_DEBUG, "No compression.\n");
574             break;
575         default:
576             av_log(avctx, AV_LOG_ERROR, "Unsupported compression format for MSZH (%d).\n", c->compression);
577             return AVERROR_INVALIDDATA;
578         }
579         break;
580 #if CONFIG_ZLIB_DECODER
581     case AV_CODEC_ID_ZLIB:
582         switch (c->compression) {
583         case COMP_ZLIB_HISPEED:
584             av_log(avctx, AV_LOG_DEBUG, "High speed compression.\n");
585             break;
586         case COMP_ZLIB_HICOMP:
587             av_log(avctx, AV_LOG_DEBUG, "High compression.\n");
588             break;
589         case COMP_ZLIB_NORMAL:
590             av_log(avctx, AV_LOG_DEBUG, "Normal compression.\n");
591             break;
592         default:
593             if (c->compression < Z_NO_COMPRESSION || c->compression > Z_BEST_COMPRESSION) {
594                 av_log(avctx, AV_LOG_ERROR, "Unsupported compression level for ZLIB: (%d).\n", c->compression);
595                 return AVERROR_INVALIDDATA;
596             }
597             av_log(avctx, AV_LOG_DEBUG, "Compression level for ZLIB: (%d).\n", c->compression);
598         }
599         break;
600 #endif
601     default:
602         av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in compression switch.\n");
603         return AVERROR_INVALIDDATA;
604     }
605 
606     /* Allocate decompression buffer */
607     if (c->decomp_size) {
608         if (!(c->decomp_buf = av_malloc(max_decomp_size))) {
609             av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
610             return AVERROR(ENOMEM);
611         }
612     }
613 
614     /* Detect flags */
615     c->flags = avctx->extradata[6];
616     if (c->flags & FLAG_MULTITHREAD)
617         av_log(avctx, AV_LOG_DEBUG, "Multithread encoder flag set.\n");
618     if (c->flags & FLAG_NULLFRAME)
619         av_log(avctx, AV_LOG_DEBUG, "Nullframe insertion flag set.\n");
620     if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER))
621         av_log(avctx, AV_LOG_DEBUG, "PNG filter flag set.\n");
622     if (c->flags & FLAGMASK_UNUSED)
623         av_log(avctx, AV_LOG_ERROR, "Unknown flag set (%d).\n", c->flags);
624 
625     /* If needed init zlib */
626 #if CONFIG_ZLIB_DECODER
627     if (avctx->codec_id == AV_CODEC_ID_ZLIB)
628         return ff_inflate_init(&c->zstream, avctx);
629 #endif
630 
631     return 0;
632 }
633 
decode_end(AVCodecContext *avctx)634 static av_cold int decode_end(AVCodecContext *avctx)
635 {
636     LclDecContext * const c = avctx->priv_data;
637 
638     av_freep(&c->decomp_buf);
639 #if CONFIG_ZLIB_DECODER
640     ff_inflate_end(&c->zstream);
641 #endif
642 
643     return 0;
644 }
645 
646 #if CONFIG_MSZH_DECODER
647 const FFCodec ff_mszh_decoder = {
648     .p.name         = "mszh",
649     .p.long_name    = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) MSZH"),
650     .p.type         = AVMEDIA_TYPE_VIDEO,
651     .p.id           = AV_CODEC_ID_MSZH,
652     .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
653     .priv_data_size = sizeof(LclDecContext),
654     .init           = decode_init,
655     .close          = decode_end,
656     FF_CODEC_DECODE_CB(decode_frame),
657     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
658 };
659 #endif
660 
661 #if CONFIG_ZLIB_DECODER
662 const FFCodec ff_zlib_decoder = {
663     .p.name         = "zlib",
664     .p.long_name    = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
665     .p.type         = AVMEDIA_TYPE_VIDEO,
666     .p.id           = AV_CODEC_ID_ZLIB,
667     .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
668     .priv_data_size = sizeof(LclDecContext),
669     .init           = decode_init,
670     .close          = decode_end,
671     FF_CODEC_DECODE_CB(decode_frame),
672     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
673 };
674 #endif
675