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)
44 #include "libavutil/mem.h"
46 #include "bytestream.h"
50 #if CONFIG_ZLIB_DECODER
57 typedef struct LclDecContext {
66 // Decompressed data size
67 unsigned int decomp_size;
68 // Decompression buffer
69 unsigned char* decomp_buf;
70 #if CONFIG_ZLIB_DECODER
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
80 static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsigned char * destptr, unsigned int destsize)
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;
88 while (srcptr < srcptr_end && destptr < destptr_end) {
89 if (!(mask & maskbit)) {
90 memcpy(destptr, srcptr, 4);
94 unsigned ofs = bytestream_get_le16(&srcptr);
95 unsigned cnt = (ofs >> 11) + 1;
97 ofs = FFMIN(ofs, destptr - destptr_bak);
99 cnt = FFMIN(cnt, destptr_end - destptr);
100 av_memcpy_backptr(destptr, ofs, cnt);
107 if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;
108 memcpy(destptr, srcptr, 32);
117 return destptr - destptr_bak;
121 #if CONFIG_ZLIB_DECODER
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
129 static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)
131 LclDecContext *c = avctx->priv_data;
132 int zret = inflateReset(&c->zstream);
134 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
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);
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);
151 return c->zstream.total_out;
161 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
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;
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;
176 unsigned int mthread_inlen, mthread_outlen;
177 unsigned int len = buf_size;
180 avctx->release_buffer(avctx, &c->pic);
182 c->pic.reference = 0;
183 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
184 if(ff_get_buffer(avctx, &c->pic) < 0){
185 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
189 outptr = c->pic.data[0]; // Output image pointer
191 /* Decompress frame */
192 switch (avctx->codec_id) {
193 case AV_CODEC_ID_MSZH:
194 switch (c->compression) {
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);
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);
214 encoded = c->decomp_buf;
215 len = c->decomp_size;
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);
223 encoded = c->decomp_buf;
227 case COMP_MSZH_NOCOMP: {
229 switch (c->imgtype) {
243 bppx2 = 0; // will error out below
246 if (len < ((width * height * bppx2) >> 1))
247 return AVERROR_INVALIDDATA;
251 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown MSZH compression in frame decoder.\n");
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;
268 } else if (c->flags & FLAG_MULTITHREAD) {
270 mthread_inlen = AV_RL32(encoded);
271 mthread_inlen = FFMIN(mthread_inlen, len - 8);
272 mthread_outlen = AV_RL32(encoded+4);
273 mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
274 ret = zlib_decomp(avctx, encoded + 8, mthread_inlen, 0, mthread_outlen);
275 if (ret < 0) return ret;
276 ret = zlib_decomp(avctx, encoded + 8 + mthread_inlen, len - 8 - mthread_inlen,
277 mthread_outlen, mthread_outlen);
278 if (ret < 0) return ret;
280 int ret = zlib_decomp(avctx, encoded, len, 0, c->decomp_size);
281 if (ret < 0) return ret;
283 encoded = c->decomp_buf;
284 len = c->decomp_size;
288 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in frame decoder compression switch.\n");
293 /* Apply PNG filter */
294 if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER)) {
295 switch (c->imgtype) {
298 for (row = 0; row < height; row++) {
299 pixel_ptr = row * width * 3;
300 yq = encoded[pixel_ptr++];
301 uqvq = AV_RL16(encoded+pixel_ptr);
303 for (col = 1; col < width; col++) {
304 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
305 uqvq -= AV_RL16(encoded+pixel_ptr+1);
306 AV_WL16(encoded+pixel_ptr+1, uqvq);
312 for (row = 0; row < height; row++) {
313 pixel_ptr = row * width * 2;
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] = uq -= encoded[pixel_ptr+5];
322 encoded[pixel_ptr+6] = vq -= encoded[pixel_ptr+6];
323 encoded[pixel_ptr+7] = vq -= encoded[pixel_ptr+7];
329 for (row = 0; row < height; row++) {
330 pixel_ptr = row * width / 2 * 3;
332 for (col = 0; col < width/4; col++) {
333 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
334 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
335 encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
336 encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
337 encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
338 encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
344 for (row = 0; row < height; row++) {
345 pixel_ptr = row * width * 2;
347 for (col = 0; col < width/2; col++) {
348 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
349 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
350 encoded[pixel_ptr+2] = uq -= encoded[pixel_ptr+2];
351 encoded[pixel_ptr+3] = vq -= encoded[pixel_ptr+3];
357 for (row = 0; row < height/2; row++) {
358 pixel_ptr = row * width * 3;
359 yq = y1q = uq = vq =0;
360 for (col = 0; col < width/2; col++) {
361 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
362 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
363 encoded[pixel_ptr+2] = y1q -= encoded[pixel_ptr+2];
364 encoded[pixel_ptr+3] = y1q -= encoded[pixel_ptr+3];
365 encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
366 encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
372 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in pngfilter switch.\n");
377 /* Convert colorspace */
378 y_out = c->pic.data[0] + (height - 1) * c->pic.linesize[0];
379 u_out = c->pic.data[1] + (height - 1) * c->pic.linesize[1];
380 v_out = c->pic.data[2] + (height - 1) * c->pic.linesize[2];
381 switch (c->imgtype) {
383 for (row = 0; row < height; row++) {
384 for (col = 0; col < width; col++) {
385 y_out[col] = *encoded++;
386 u_out[col] = *encoded++ + 128;
387 v_out[col] = *encoded++ + 128;
389 y_out -= c->pic.linesize[0];
390 u_out -= c->pic.linesize[1];
391 v_out -= c->pic.linesize[2];
395 for (row = 0; row < height; row++) {
396 for (col = 0; col < width - 3; col += 4) {
397 memcpy(y_out + col, encoded, 4);
399 u_out[ col >> 1 ] = *encoded++ + 128;
400 u_out[(col >> 1) + 1] = *encoded++ + 128;
401 v_out[ col >> 1 ] = *encoded++ + 128;
402 v_out[(col >> 1) + 1] = *encoded++ + 128;
404 y_out -= c->pic.linesize[0];
405 u_out -= c->pic.linesize[1];
406 v_out -= c->pic.linesize[2];
410 for (row = height - 1; row >= 0; row--) {
411 pixel_ptr = row * c->pic.linesize[0];
412 memcpy(outptr + pixel_ptr, encoded, 3 * width);
413 encoded += 3 * width;
417 for (row = 0; row < height; row++) {
418 for (col = 0; col < width - 3; col += 4) {
419 memcpy(y_out + col, encoded, 4);
421 u_out[col >> 2] = *encoded++ + 128;
422 v_out[col >> 2] = *encoded++ + 128;
424 y_out -= c->pic.linesize[0];
425 u_out -= c->pic.linesize[1];
426 v_out -= c->pic.linesize[2];
430 for (row = 0; row < height; row++) {
431 for (col = 0; col < width - 1; col += 2) {
432 memcpy(y_out + col, encoded, 2);
434 u_out[col >> 1] = *encoded++ + 128;
435 v_out[col >> 1] = *encoded++ + 128;
437 y_out -= c->pic.linesize[0];
438 u_out -= c->pic.linesize[1];
439 v_out -= c->pic.linesize[2];
443 u_out = c->pic.data[1] + ((height >> 1) - 1) * c->pic.linesize[1];
444 v_out = c->pic.data[2] + ((height >> 1) - 1) * c->pic.linesize[2];
445 for (row = 0; row < height - 1; row += 2) {
446 for (col = 0; col < width - 1; col += 2) {
447 memcpy(y_out + col, encoded, 2);
449 memcpy(y_out + col - c->pic.linesize[0], encoded, 2);
451 u_out[col >> 1] = *encoded++ + 128;
452 v_out[col >> 1] = *encoded++ + 128;
454 y_out -= c->pic.linesize[0] << 1;
455 u_out -= c->pic.linesize[1];
456 v_out -= c->pic.linesize[2];
460 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in image decoder.\n");
465 *(AVFrame*)data = c->pic;
467 /* always report that the buffer was completely consumed */
476 static av_cold int decode_init(AVCodecContext *avctx)
478 LclDecContext * const c = avctx->priv_data;
479 unsigned int basesize = avctx->width * avctx->height;
480 unsigned int max_basesize = FFALIGN(avctx->width, 4) *
481 FFALIGN(avctx->height, 4);
482 unsigned int max_decomp_size;
484 if (avctx->extradata_size < 8) {
485 av_log(avctx, AV_LOG_ERROR, "Extradata size too small.\n");
486 return AVERROR_INVALIDDATA;
489 /* Check codec type */
490 if ((avctx->codec_id == AV_CODEC_ID_MSZH && avctx->extradata[7] != CODEC_MSZH) ||
491 (avctx->codec_id == AV_CODEC_ID_ZLIB && avctx->extradata[7] != CODEC_ZLIB)) {
492 av_log(avctx, AV_LOG_ERROR, "Codec id and codec type mismatch. This should not happen.\n");
495 /* Detect image type */
496 switch (c->imgtype = avctx->extradata[4]) {
498 c->decomp_size = basesize * 3;
499 max_decomp_size = max_basesize * 3;
500 avctx->pix_fmt = AV_PIX_FMT_YUV444P;
501 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 1:1:1.\n");
504 c->decomp_size = basesize * 2;
505 max_decomp_size = max_basesize * 2;
506 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
507 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:2.\n");
510 c->decomp_size = basesize * 3;
511 max_decomp_size = max_basesize * 3;
512 avctx->pix_fmt = AV_PIX_FMT_BGR24;
513 av_log(avctx, AV_LOG_DEBUG, "Image type is RGB 24.\n");
516 c->decomp_size = basesize / 2 * 3;
517 max_decomp_size = max_basesize / 2 * 3;
518 avctx->pix_fmt = AV_PIX_FMT_YUV411P;
519 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:1:1.\n");
522 c->decomp_size = basesize * 2;
523 max_decomp_size = max_basesize * 2;
524 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
525 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 2:1:1.\n");
528 c->decomp_size = basesize / 2 * 3;
529 max_decomp_size = max_basesize / 2 * 3;
530 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
531 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:0.\n");
534 av_log(avctx, AV_LOG_ERROR, "Unsupported image format %d.\n", c->imgtype);
535 return AVERROR_INVALIDDATA;
538 /* Detect compression method */
539 c->compression = (int8_t)avctx->extradata[5];
540 switch (avctx->codec_id) {
541 case AV_CODEC_ID_MSZH:
542 switch (c->compression) {
544 av_log(avctx, AV_LOG_DEBUG, "Compression enabled.\n");
546 case COMP_MSZH_NOCOMP:
548 av_log(avctx, AV_LOG_DEBUG, "No compression.\n");
551 av_log(avctx, AV_LOG_ERROR, "Unsupported compression format for MSZH (%d).\n", c->compression);
552 return AVERROR_INVALIDDATA;
555 #if CONFIG_ZLIB_DECODER
556 case AV_CODEC_ID_ZLIB:
557 switch (c->compression) {
558 case COMP_ZLIB_HISPEED:
559 av_log(avctx, AV_LOG_DEBUG, "High speed compression.\n");
561 case COMP_ZLIB_HICOMP:
562 av_log(avctx, AV_LOG_DEBUG, "High compression.\n");
564 case COMP_ZLIB_NORMAL:
565 av_log(avctx, AV_LOG_DEBUG, "Normal compression.\n");
568 if (c->compression < Z_NO_COMPRESSION || c->compression > Z_BEST_COMPRESSION) {
569 av_log(avctx, AV_LOG_ERROR, "Unsupported compression level for ZLIB: (%d).\n", c->compression);
570 return AVERROR_INVALIDDATA;
572 av_log(avctx, AV_LOG_DEBUG, "Compression level for ZLIB: (%d).\n", c->compression);
577 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in compression switch.\n");
578 return AVERROR_INVALIDDATA;
581 /* Allocate decompression buffer */
582 if (c->decomp_size) {
583 if ((c->decomp_buf = av_malloc(max_decomp_size)) == NULL) {
584 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
585 return AVERROR(ENOMEM);
590 c->flags = avctx->extradata[6];
591 if (c->flags & FLAG_MULTITHREAD)
592 av_log(avctx, AV_LOG_DEBUG, "Multithread encoder flag set.\n");
593 if (c->flags & FLAG_NULLFRAME)
594 av_log(avctx, AV_LOG_DEBUG, "Nullframe insertion flag set.\n");
595 if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER))
596 av_log(avctx, AV_LOG_DEBUG, "PNG filter flag set.\n");
597 if (c->flags & FLAGMASK_UNUSED)
598 av_log(avctx, AV_LOG_ERROR, "Unknown flag set (%d).\n", c->flags);
600 /* If needed init zlib */
601 #if CONFIG_ZLIB_DECODER
602 if (avctx->codec_id == AV_CODEC_ID_ZLIB) {
604 c->zstream.zalloc = Z_NULL;
605 c->zstream.zfree = Z_NULL;
606 c->zstream.opaque = Z_NULL;
607 zret = inflateInit(&c->zstream);
609 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
610 av_freep(&c->decomp_buf);
611 return AVERROR_UNKNOWN;
624 static av_cold int decode_end(AVCodecContext *avctx)
626 LclDecContext * const c = avctx->priv_data;
628 av_freep(&c->decomp_buf);
630 avctx->release_buffer(avctx, &c->pic);
631 #if CONFIG_ZLIB_DECODER
632 if (avctx->codec_id == AV_CODEC_ID_ZLIB)
633 inflateEnd(&c->zstream);
639 #if CONFIG_MSZH_DECODER
640 AVCodec ff_mszh_decoder = {
642 .type = AVMEDIA_TYPE_VIDEO,
643 .id = AV_CODEC_ID_MSZH,
644 .priv_data_size = sizeof(LclDecContext),
647 .decode = decode_frame,
648 .capabilities = CODEC_CAP_DR1,
649 .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) MSZH"),
653 #if CONFIG_ZLIB_DECODER
654 AVCodec ff_zlib_decoder = {
656 .type = AVMEDIA_TYPE_VIDEO,
657 .id = AV_CODEC_ID_ZLIB,
658 .priv_data_size = sizeof(LclDecContext),
661 .decode = decode_frame,
662 .capabilities = CODEC_CAP_DR1,
663 .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),