2 * LCL (LossLess Codec Library) Codec
3 * Copyright (c) 2002-2004 Roberto Togni
5 * This file is part of Libav.
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.
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.
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
24 * LCL (LossLess Codec Library) Video Codec
25 * Decoder for MSZH and ZLIB codecs
26 * Experimental encoder for ZLIB RGB24
31 * Ver2.23 By Kenji Oshima 2000.09.20
32 * avimszh.dll, avizlib.dll
34 * A description of the decoding algorithm can be found here:
35 * http://www.pcisys.net/~melanson/codecs
37 * Supports: BGR24 (RGB 24bpp)
43 #include "libavutil/mem.h"
45 #include "bytestream.h"
49 #if CONFIG_ZLIB_DECODER
53 typedef struct LclDecContext {
60 // Decompressed data size
61 unsigned int decomp_size;
62 // Decompression buffer
63 unsigned char* decomp_buf;
64 #if CONFIG_ZLIB_DECODER
71 * @param srcptr compressed source buffer, must be padded with at least 5 extra bytes
72 * @param destptr must be padded sufficiently for av_memcpy_backptr
74 static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsigned char * destptr, unsigned int destsize)
76 unsigned char *destptr_bak = destptr;
77 unsigned char *destptr_end = destptr + destsize;
78 const unsigned char *srcptr_end = srcptr + srclen;
79 unsigned mask = *srcptr++;
80 unsigned maskbit = 0x80;
82 while (srcptr < srcptr_end && destptr < destptr_end) {
83 if (!(mask & maskbit)) {
84 memcpy(destptr, srcptr, 4);
88 unsigned ofs = bytestream_get_le16(&srcptr);
89 unsigned cnt = (ofs >> 11) + 1;
91 ofs = FFMIN(ofs, destptr - destptr_bak);
93 cnt = FFMIN(cnt, destptr_end - destptr);
94 av_memcpy_backptr(destptr, ofs, cnt);
101 if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;
102 memcpy(destptr, srcptr, 32);
111 return destptr - destptr_bak;
115 #if CONFIG_ZLIB_DECODER
117 * @brief decompress a zlib-compressed data block into decomp_buf
118 * @param src compressed input buffer
119 * @param src_len data length in input buffer
120 * @param offset offset in decomp_buf
121 * @param expected expected decompressed length
123 static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)
125 LclDecContext *c = avctx->priv_data;
126 int zret = inflateReset(&c->zstream);
128 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
129 return AVERROR_UNKNOWN;
131 c->zstream.next_in = src;
132 c->zstream.avail_in = src_len;
133 c->zstream.next_out = c->decomp_buf + offset;
134 c->zstream.avail_out = c->decomp_size - offset;
135 zret = inflate(&c->zstream, Z_FINISH);
136 if (zret != Z_OK && zret != Z_STREAM_END) {
137 av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
138 return AVERROR_UNKNOWN;
140 if (expected != (unsigned int)c->zstream.total_out) {
141 av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %lu)\n",
142 expected, c->zstream.total_out);
143 return AVERROR_UNKNOWN;
145 return c->zstream.total_out;
150 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
152 AVFrame *frame = data;
153 const uint8_t *buf = avpkt->data;
154 int buf_size = avpkt->size;
155 LclDecContext * const c = avctx->priv_data;
156 unsigned int pixel_ptr;
158 unsigned char *encoded, *outptr;
159 uint8_t *y_out, *u_out, *v_out;
160 unsigned int width = avctx->width; // Real image width
161 unsigned int height = avctx->height; // Real image height
162 unsigned int mszh_dlen;
163 unsigned char yq, y1q, uq, vq;
165 unsigned int mthread_inlen, mthread_outlen;
166 unsigned int len = buf_size;
168 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
169 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
173 outptr = frame->data[0]; // Output image pointer
175 /* Decompress frame */
176 switch (avctx->codec_id) {
177 case AV_CODEC_ID_MSZH:
178 switch (c->compression) {
180 if (c->flags & FLAG_MULTITHREAD) {
181 mthread_inlen = AV_RL32(buf);
182 mthread_inlen = FFMIN(mthread_inlen, len - 8);
183 mthread_outlen = AV_RL32(buf + 4);
184 mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
185 mszh_dlen = mszh_decomp(buf + 8, mthread_inlen, c->decomp_buf, c->decomp_size);
186 if (mthread_outlen != mszh_dlen) {
187 av_log(avctx, AV_LOG_ERROR, "Mthread1 decoded size differs (%d != %d)\n",
188 mthread_outlen, mszh_dlen);
189 return AVERROR_INVALIDDATA;
191 mszh_dlen = mszh_decomp(buf + 8 + mthread_inlen, len - 8 - mthread_inlen,
192 c->decomp_buf + mthread_outlen, c->decomp_size - mthread_outlen);
193 if (mthread_outlen != mszh_dlen) {
194 av_log(avctx, AV_LOG_ERROR, "Mthread2 decoded size differs (%d != %d)\n",
195 mthread_outlen, mszh_dlen);
196 return AVERROR_INVALIDDATA;
198 encoded = c->decomp_buf;
199 len = c->decomp_size;
201 mszh_dlen = mszh_decomp(buf, len, c->decomp_buf, c->decomp_size);
202 if (c->decomp_size != mszh_dlen) {
203 av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %d)\n",
204 c->decomp_size, mszh_dlen);
205 return AVERROR_INVALIDDATA;
207 encoded = c->decomp_buf;
211 case COMP_MSZH_NOCOMP: {
213 switch (c->imgtype) {
227 bppx2 = 0; // will error out below
230 if (len < ((width * height * bppx2) >> 1))
231 return AVERROR_INVALIDDATA;
235 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown MSZH compression in frame decoder.\n");
236 return AVERROR_INVALIDDATA;
239 #if CONFIG_ZLIB_DECODER
240 case AV_CODEC_ID_ZLIB:
241 /* Using the original dll with normal compression (-1) and RGB format
242 * gives a file with ZLIB fourcc, but frame is really uncompressed.
243 * To be sure that's true check also frame size */
244 if (c->compression == COMP_ZLIB_NORMAL && c->imgtype == IMGTYPE_RGB24 &&
245 len == width * height * 3) {
246 if (c->flags & FLAG_PNGFILTER) {
247 memcpy(c->decomp_buf, buf, len);
248 encoded = c->decomp_buf;
252 } else if (c->flags & FLAG_MULTITHREAD) {
253 mthread_inlen = AV_RL32(buf);
254 mthread_inlen = FFMIN(mthread_inlen, len - 8);
255 mthread_outlen = AV_RL32(buf + 4);
256 mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
257 ret = zlib_decomp(avctx, buf + 8, mthread_inlen, 0, mthread_outlen);
258 if (ret < 0) return ret;
259 ret = zlib_decomp(avctx, buf + 8 + mthread_inlen, len - 8 - mthread_inlen,
260 mthread_outlen, mthread_outlen);
261 if (ret < 0) return ret;
263 int ret = zlib_decomp(avctx, buf, len, 0, c->decomp_size);
264 if (ret < 0) return ret;
266 encoded = c->decomp_buf;
267 len = c->decomp_size;
271 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in frame decoder compression switch.\n");
272 return AVERROR_INVALIDDATA;
276 /* Apply PNG filter */
277 if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER)) {
278 switch (c->imgtype) {
281 for (row = 0; row < height; row++) {
282 pixel_ptr = row * width * 3;
283 yq = encoded[pixel_ptr++];
284 uqvq = AV_RL16(encoded+pixel_ptr);
286 for (col = 1; col < width; col++) {
287 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
288 uqvq -= AV_RL16(encoded+pixel_ptr+1);
289 AV_WL16(encoded+pixel_ptr+1, uqvq);
295 for (row = 0; row < height; row++) {
296 pixel_ptr = row * width * 2;
298 for (col = 0; col < width/4; col++) {
299 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
300 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
301 encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
302 encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
303 encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
304 encoded[pixel_ptr+5] = uq -= encoded[pixel_ptr+5];
305 encoded[pixel_ptr+6] = vq -= encoded[pixel_ptr+6];
306 encoded[pixel_ptr+7] = vq -= encoded[pixel_ptr+7];
312 for (row = 0; row < height; row++) {
313 pixel_ptr = row * width / 2 * 3;
315 for (col = 0; col < width/4; col++) {
316 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
317 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
318 encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
319 encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
320 encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
321 encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
327 for (row = 0; row < height; row++) {
328 pixel_ptr = row * width * 2;
330 for (col = 0; col < width/2; col++) {
331 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
332 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
333 encoded[pixel_ptr+2] = uq -= encoded[pixel_ptr+2];
334 encoded[pixel_ptr+3] = vq -= encoded[pixel_ptr+3];
340 for (row = 0; row < height/2; row++) {
341 pixel_ptr = row * width * 3;
342 yq = y1q = uq = vq =0;
343 for (col = 0; col < width/2; col++) {
344 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
345 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
346 encoded[pixel_ptr+2] = y1q -= encoded[pixel_ptr+2];
347 encoded[pixel_ptr+3] = y1q -= encoded[pixel_ptr+3];
348 encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
349 encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
355 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in pngfilter switch.\n");
356 return AVERROR_INVALIDDATA;
360 /* Convert colorspace */
361 y_out = frame->data[0] + (height - 1) * frame->linesize[0];
362 u_out = frame->data[1] + (height - 1) * frame->linesize[1];
363 v_out = frame->data[2] + (height - 1) * frame->linesize[2];
364 switch (c->imgtype) {
366 for (row = 0; row < height; row++) {
367 for (col = 0; col < width; col++) {
368 y_out[col] = *encoded++;
369 u_out[col] = *encoded++ + 128;
370 v_out[col] = *encoded++ + 128;
372 y_out -= frame->linesize[0];
373 u_out -= frame->linesize[1];
374 v_out -= frame->linesize[2];
378 for (row = 0; row < height; row++) {
379 for (col = 0; col < width - 3; col += 4) {
380 memcpy(y_out + col, encoded, 4);
382 u_out[ col >> 1 ] = *encoded++ + 128;
383 u_out[(col >> 1) + 1] = *encoded++ + 128;
384 v_out[ col >> 1 ] = *encoded++ + 128;
385 v_out[(col >> 1) + 1] = *encoded++ + 128;
387 y_out -= frame->linesize[0];
388 u_out -= frame->linesize[1];
389 v_out -= frame->linesize[2];
393 for (row = height - 1; row >= 0; row--) {
394 pixel_ptr = row * frame->linesize[0];
395 memcpy(outptr + pixel_ptr, encoded, 3 * width);
396 encoded += 3 * width;
400 for (row = 0; row < height; row++) {
401 for (col = 0; col < width - 3; col += 4) {
402 memcpy(y_out + col, encoded, 4);
404 u_out[col >> 2] = *encoded++ + 128;
405 v_out[col >> 2] = *encoded++ + 128;
407 y_out -= frame->linesize[0];
408 u_out -= frame->linesize[1];
409 v_out -= frame->linesize[2];
413 for (row = 0; row < height; row++) {
414 for (col = 0; col < width - 1; col += 2) {
415 memcpy(y_out + col, encoded, 2);
417 u_out[col >> 1] = *encoded++ + 128;
418 v_out[col >> 1] = *encoded++ + 128;
420 y_out -= frame->linesize[0];
421 u_out -= frame->linesize[1];
422 v_out -= frame->linesize[2];
426 u_out = frame->data[1] + ((height >> 1) - 1) * frame->linesize[1];
427 v_out = frame->data[2] + ((height >> 1) - 1) * frame->linesize[2];
428 for (row = 0; row < height - 1; row += 2) {
429 for (col = 0; col < width - 1; col += 2) {
430 memcpy(y_out + col, encoded, 2);
432 memcpy(y_out + col - frame->linesize[0], encoded, 2);
434 u_out[col >> 1] = *encoded++ + 128;
435 v_out[col >> 1] = *encoded++ + 128;
437 y_out -= frame->linesize[0] << 1;
438 u_out -= frame->linesize[1];
439 v_out -= frame->linesize[2];
443 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in image decoder.\n");
444 return AVERROR_INVALIDDATA;
449 /* always report that the buffer was completely consumed */
453 static av_cold int decode_init(AVCodecContext *avctx)
455 LclDecContext * const c = avctx->priv_data;
456 unsigned int basesize = avctx->width * avctx->height;
457 unsigned int max_basesize = FFALIGN(avctx->width, 4) *
458 FFALIGN(avctx->height, 4);
459 unsigned int max_decomp_size;
461 if (avctx->extradata_size < 8) {
462 av_log(avctx, AV_LOG_ERROR, "Extradata size too small.\n");
463 return AVERROR_INVALIDDATA;
466 /* Check codec type */
467 if ((avctx->codec_id == AV_CODEC_ID_MSZH && avctx->extradata[7] != CODEC_MSZH) ||
468 (avctx->codec_id == AV_CODEC_ID_ZLIB && avctx->extradata[7] != CODEC_ZLIB)) {
469 av_log(avctx, AV_LOG_ERROR, "Codec id and codec type mismatch. This should not happen.\n");
472 /* Detect image type */
473 switch (c->imgtype = avctx->extradata[4]) {
475 c->decomp_size = basesize * 3;
476 max_decomp_size = max_basesize * 3;
477 avctx->pix_fmt = AV_PIX_FMT_YUV444P;
478 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 1:1:1.\n");
481 c->decomp_size = basesize * 2;
482 max_decomp_size = max_basesize * 2;
483 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
484 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:2.\n");
487 c->decomp_size = basesize * 3;
488 max_decomp_size = max_basesize * 3;
489 avctx->pix_fmt = AV_PIX_FMT_BGR24;
490 av_log(avctx, AV_LOG_DEBUG, "Image type is RGB 24.\n");
493 c->decomp_size = basesize / 2 * 3;
494 max_decomp_size = max_basesize / 2 * 3;
495 avctx->pix_fmt = AV_PIX_FMT_YUV411P;
496 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:1:1.\n");
499 c->decomp_size = basesize * 2;
500 max_decomp_size = max_basesize * 2;
501 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
502 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 2:1:1.\n");
505 c->decomp_size = basesize / 2 * 3;
506 max_decomp_size = max_basesize / 2 * 3;
507 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
508 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:0.\n");
511 av_log(avctx, AV_LOG_ERROR, "Unsupported image format %d.\n", c->imgtype);
512 return AVERROR_INVALIDDATA;
515 /* Detect compression method */
516 c->compression = (int8_t)avctx->extradata[5];
517 switch (avctx->codec_id) {
518 case AV_CODEC_ID_MSZH:
519 switch (c->compression) {
521 av_log(avctx, AV_LOG_DEBUG, "Compression enabled.\n");
523 case COMP_MSZH_NOCOMP:
525 av_log(avctx, AV_LOG_DEBUG, "No compression.\n");
528 av_log(avctx, AV_LOG_ERROR, "Unsupported compression format for MSZH (%d).\n", c->compression);
529 return AVERROR_INVALIDDATA;
532 #if CONFIG_ZLIB_DECODER
533 case AV_CODEC_ID_ZLIB:
534 switch (c->compression) {
535 case COMP_ZLIB_HISPEED:
536 av_log(avctx, AV_LOG_DEBUG, "High speed compression.\n");
538 case COMP_ZLIB_HICOMP:
539 av_log(avctx, AV_LOG_DEBUG, "High compression.\n");
541 case COMP_ZLIB_NORMAL:
542 av_log(avctx, AV_LOG_DEBUG, "Normal compression.\n");
545 if (c->compression < Z_NO_COMPRESSION || c->compression > Z_BEST_COMPRESSION) {
546 av_log(avctx, AV_LOG_ERROR, "Unsupported compression level for ZLIB: (%d).\n", c->compression);
547 return AVERROR_INVALIDDATA;
549 av_log(avctx, AV_LOG_DEBUG, "Compression level for ZLIB: (%d).\n", c->compression);
554 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in compression switch.\n");
555 return AVERROR_INVALIDDATA;
558 /* Allocate decompression buffer */
559 if (c->decomp_size) {
560 if (!(c->decomp_buf = av_malloc(max_decomp_size))) {
561 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
562 return AVERROR(ENOMEM);
567 c->flags = avctx->extradata[6];
568 if (c->flags & FLAG_MULTITHREAD)
569 av_log(avctx, AV_LOG_DEBUG, "Multithread encoder flag set.\n");
570 if (c->flags & FLAG_NULLFRAME)
571 av_log(avctx, AV_LOG_DEBUG, "Nullframe insertion flag set.\n");
572 if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER))
573 av_log(avctx, AV_LOG_DEBUG, "PNG filter flag set.\n");
574 if (c->flags & FLAGMASK_UNUSED)
575 av_log(avctx, AV_LOG_ERROR, "Unknown flag set (%d).\n", c->flags);
577 /* If needed init zlib */
578 #if CONFIG_ZLIB_DECODER
579 if (avctx->codec_id == AV_CODEC_ID_ZLIB) {
581 c->zstream.zalloc = Z_NULL;
582 c->zstream.zfree = Z_NULL;
583 c->zstream.opaque = Z_NULL;
584 zret = inflateInit(&c->zstream);
586 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
587 av_freep(&c->decomp_buf);
588 return AVERROR_UNKNOWN;
596 static av_cold int decode_end(AVCodecContext *avctx)
598 LclDecContext * const c = avctx->priv_data;
600 av_freep(&c->decomp_buf);
601 #if CONFIG_ZLIB_DECODER
602 if (avctx->codec_id == AV_CODEC_ID_ZLIB)
603 inflateEnd(&c->zstream);
609 #if CONFIG_MSZH_DECODER
610 AVCodec ff_mszh_decoder = {
612 .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) MSZH"),
613 .type = AVMEDIA_TYPE_VIDEO,
614 .id = AV_CODEC_ID_MSZH,
615 .priv_data_size = sizeof(LclDecContext),
618 .decode = decode_frame,
619 .capabilities = AV_CODEC_CAP_DR1,
623 #if CONFIG_ZLIB_DECODER
624 AVCodec ff_zlib_decoder = {
626 .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
627 .type = AVMEDIA_TYPE_VIDEO,
628 .id = AV_CODEC_ID_ZLIB,
629 .priv_data_size = sizeof(LclDecContext),
632 .decode = decode_frame,
633 .capabilities = AV_CODEC_CAP_DR1,