2 * LCL (LossLess Codec Library) Codec
3 * Copyright (c) 2002-2004 Roberto Togni
5 * This file is part of FFmpeg.
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.
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.
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
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);
101 av_memcpy_backptr(destptr, ofs, cnt);
103 // Not known what the correct behaviour is, but
104 // this at least avoids uninitialized data.
105 memset(destptr, 0, cnt);
113 if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;
114 memcpy(destptr, srcptr, 32);
123 return destptr - destptr_bak;
127 #if CONFIG_ZLIB_DECODER
129 * @brief decompress a zlib-compressed data block into decomp_buf
130 * @param src compressed input buffer
131 * @param src_len data length in input buffer
132 * @param offset offset in decomp_buf
133 * @param expected expected decompressed length
135 static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)
137 LclDecContext *c = avctx->priv_data;
138 int zret = inflateReset(&c->zstream);
140 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
141 return AVERROR_UNKNOWN;
143 c->zstream.next_in = (uint8_t *)src;
144 c->zstream.avail_in = src_len;
145 c->zstream.next_out = c->decomp_buf + offset;
146 c->zstream.avail_out = c->decomp_size - offset;
147 zret = inflate(&c->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;
152 if (expected != (unsigned int)c->zstream.total_out) {
153 av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %lu)\n",
154 expected, c->zstream.total_out);
155 return AVERROR_UNKNOWN;
157 return c->zstream.total_out;
167 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
169 const uint8_t *buf = avpkt->data;
170 int buf_size = avpkt->size;
171 LclDecContext * const c = avctx->priv_data;
172 unsigned char *encoded = (unsigned char *)buf;
173 unsigned int pixel_ptr;
175 unsigned char *outptr;
176 uint8_t *y_out, *u_out, *v_out;
177 unsigned int width = avctx->width; // Real image width
178 unsigned int height = avctx->height; // Real image height
179 unsigned int mszh_dlen;
180 unsigned char yq, y1q, uq, vq;
182 unsigned int mthread_inlen, mthread_outlen;
183 unsigned int len = buf_size;
186 avctx->release_buffer(avctx, &c->pic);
188 c->pic.reference = 0;
189 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
190 if ((ret = ff_get_buffer(avctx, &c->pic)) < 0) {
191 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
195 outptr = c->pic.data[0]; // Output image pointer
197 /* Decompress frame */
198 switch (avctx->codec_id) {
199 case AV_CODEC_ID_MSZH:
200 switch (c->compression) {
202 if (c->imgtype == IMGTYPE_RGB24 && len == width * height * 3) {
204 } else if (c->flags & FLAG_MULTITHREAD) {
205 mthread_inlen = AV_RL32(encoded);
206 mthread_inlen = FFMIN(mthread_inlen, len - 8);
207 mthread_outlen = AV_RL32(encoded+4);
208 mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
209 mszh_dlen = mszh_decomp(encoded + 8, mthread_inlen, c->decomp_buf, c->decomp_size);
210 if (mthread_outlen != mszh_dlen) {
211 av_log(avctx, AV_LOG_ERROR, "Mthread1 decoded size differs (%d != %d)\n",
212 mthread_outlen, mszh_dlen);
213 return AVERROR_INVALIDDATA;
215 mszh_dlen = mszh_decomp(encoded + 8 + mthread_inlen, len - 8 - mthread_inlen,
216 c->decomp_buf + mthread_outlen, c->decomp_size - mthread_outlen);
217 if (mthread_outlen != mszh_dlen) {
218 av_log(avctx, AV_LOG_ERROR, "Mthread2 decoded size differs (%d != %d)\n",
219 mthread_outlen, mszh_dlen);
220 return AVERROR_INVALIDDATA;
222 encoded = c->decomp_buf;
223 len = c->decomp_size;
225 mszh_dlen = mszh_decomp(encoded, len, c->decomp_buf, c->decomp_size);
226 if (c->decomp_size != mszh_dlen) {
227 av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %d)\n",
228 c->decomp_size, mszh_dlen);
229 return AVERROR_INVALIDDATA;
231 encoded = c->decomp_buf;
235 case COMP_MSZH_NOCOMP: {
237 switch (c->imgtype) {
251 bppx2 = 0; // will error out below
254 if (len < ((width * height * bppx2) >> 1))
255 return AVERROR_INVALIDDATA;
259 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown MSZH compression in frame decoder.\n");
260 return AVERROR_INVALIDDATA;
263 #if CONFIG_ZLIB_DECODER
264 case AV_CODEC_ID_ZLIB:
265 /* Using the original dll with normal compression (-1) and RGB format
266 * gives a file with ZLIB fourcc, but frame is really uncompressed.
267 * To be sure that's true check also frame size */
268 if (c->compression == COMP_ZLIB_NORMAL && c->imgtype == IMGTYPE_RGB24 &&
269 len == width * height * 3) {
270 if (c->flags & FLAG_PNGFILTER) {
271 memcpy(c->decomp_buf, encoded, len);
272 encoded = c->decomp_buf;
276 } else if (c->flags & FLAG_MULTITHREAD) {
277 mthread_inlen = AV_RL32(encoded);
278 mthread_inlen = FFMIN(mthread_inlen, len - 8);
279 mthread_outlen = AV_RL32(encoded+4);
280 mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
281 ret = zlib_decomp(avctx, encoded + 8, mthread_inlen, 0, mthread_outlen);
282 if (ret < 0) return ret;
283 ret = zlib_decomp(avctx, encoded + 8 + mthread_inlen, len - 8 - mthread_inlen,
284 mthread_outlen, mthread_outlen);
285 if (ret < 0) return ret;
287 int ret = zlib_decomp(avctx, encoded, len, 0, c->decomp_size);
288 if (ret < 0) return ret;
290 encoded = c->decomp_buf;
291 len = c->decomp_size;
295 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in frame decoder compression switch.\n");
296 return AVERROR_INVALIDDATA;
300 /* Apply PNG filter */
301 if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER)) {
302 switch (c->imgtype) {
305 for (row = 0; row < height; row++) {
306 pixel_ptr = row * width * 3;
307 yq = encoded[pixel_ptr++];
308 uqvq = AV_RL16(encoded+pixel_ptr);
310 for (col = 1; col < width; col++) {
311 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
312 uqvq -= AV_RL16(encoded+pixel_ptr+1);
313 AV_WL16(encoded+pixel_ptr+1, uqvq);
319 for (row = 0; row < height; row++) {
320 pixel_ptr = row * width * 2;
322 for (col = 0; col < width/4; col++) {
323 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
324 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
325 encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
326 encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
327 encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
328 encoded[pixel_ptr+5] = uq -= encoded[pixel_ptr+5];
329 encoded[pixel_ptr+6] = vq -= encoded[pixel_ptr+6];
330 encoded[pixel_ptr+7] = vq -= encoded[pixel_ptr+7];
336 for (row = 0; row < height; row++) {
337 pixel_ptr = row * width / 2 * 3;
339 for (col = 0; col < width/4; col++) {
340 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
341 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
342 encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
343 encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
344 encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
345 encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
351 for (row = 0; row < height; row++) {
352 pixel_ptr = row * width * 2;
354 for (col = 0; col < width/2; col++) {
355 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
356 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
357 encoded[pixel_ptr+2] = uq -= encoded[pixel_ptr+2];
358 encoded[pixel_ptr+3] = vq -= encoded[pixel_ptr+3];
364 for (row = 0; row < height/2; row++) {
365 pixel_ptr = row * width * 3;
366 yq = y1q = uq = vq =0;
367 for (col = 0; col < width/2; col++) {
368 encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
369 encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
370 encoded[pixel_ptr+2] = y1q -= encoded[pixel_ptr+2];
371 encoded[pixel_ptr+3] = y1q -= encoded[pixel_ptr+3];
372 encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
373 encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
379 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in pngfilter switch.\n");
380 return AVERROR_INVALIDDATA;
384 /* Convert colorspace */
385 y_out = c->pic.data[0] + (height - 1) * c->pic.linesize[0];
386 u_out = c->pic.data[1] + (height - 1) * c->pic.linesize[1];
387 v_out = c->pic.data[2] + (height - 1) * c->pic.linesize[2];
388 switch (c->imgtype) {
390 for (row = 0; row < height; row++) {
391 for (col = 0; col < width; col++) {
392 y_out[col] = *encoded++;
393 u_out[col] = *encoded++ + 128;
394 v_out[col] = *encoded++ + 128;
396 y_out -= c->pic.linesize[0];
397 u_out -= c->pic.linesize[1];
398 v_out -= c->pic.linesize[2];
402 for (row = 0; row < height; row++) {
403 for (col = 0; col < width - 3; col += 4) {
404 memcpy(y_out + col, encoded, 4);
406 u_out[ col >> 1 ] = *encoded++ + 128;
407 u_out[(col >> 1) + 1] = *encoded++ + 128;
408 v_out[ col >> 1 ] = *encoded++ + 128;
409 v_out[(col >> 1) + 1] = *encoded++ + 128;
411 y_out -= c->pic.linesize[0];
412 u_out -= c->pic.linesize[1];
413 v_out -= c->pic.linesize[2];
417 for (row = height - 1; row >= 0; row--) {
418 pixel_ptr = row * c->pic.linesize[0];
419 memcpy(outptr + pixel_ptr, encoded, 3 * width);
420 encoded += 3 * width;
424 for (row = 0; row < height; row++) {
425 for (col = 0; col < width - 3; col += 4) {
426 memcpy(y_out + col, encoded, 4);
428 u_out[col >> 2] = *encoded++ + 128;
429 v_out[col >> 2] = *encoded++ + 128;
431 y_out -= c->pic.linesize[0];
432 u_out -= c->pic.linesize[1];
433 v_out -= c->pic.linesize[2];
437 for (row = 0; row < height; row++) {
438 for (col = 0; col < width - 1; col += 2) {
439 memcpy(y_out + col, encoded, 2);
441 u_out[col >> 1] = *encoded++ + 128;
442 v_out[col >> 1] = *encoded++ + 128;
444 y_out -= c->pic.linesize[0];
445 u_out -= c->pic.linesize[1];
446 v_out -= c->pic.linesize[2];
450 u_out = c->pic.data[1] + ((height >> 1) - 1) * c->pic.linesize[1];
451 v_out = c->pic.data[2] + ((height >> 1) - 1) * c->pic.linesize[2];
452 for (row = 0; row < height - 1; row += 2) {
453 for (col = 0; col < width - 1; col += 2) {
454 memcpy(y_out + col, encoded, 2);
456 memcpy(y_out + col - c->pic.linesize[0], encoded, 2);
458 u_out[col >> 1] = *encoded++ + 128;
459 v_out[col >> 1] = *encoded++ + 128;
461 y_out -= c->pic.linesize[0] << 1;
462 u_out -= c->pic.linesize[1];
463 v_out -= c->pic.linesize[2];
467 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in image decoder.\n");
468 return AVERROR_INVALIDDATA;
472 *(AVFrame*)data = c->pic;
474 /* always report that the buffer was completely consumed */
483 static av_cold int decode_init(AVCodecContext *avctx)
485 LclDecContext * const c = avctx->priv_data;
486 unsigned int basesize = avctx->width * avctx->height;
487 unsigned int max_basesize = FFALIGN(avctx->width, 4) *
488 FFALIGN(avctx->height, 4);
489 unsigned int max_decomp_size;
491 avcodec_get_frame_defaults(&c->pic);
492 if (avctx->extradata_size < 8) {
493 av_log(avctx, AV_LOG_ERROR, "Extradata size too small.\n");
494 return AVERROR_INVALIDDATA;
497 /* Check codec type */
498 if ((avctx->codec_id == AV_CODEC_ID_MSZH && avctx->extradata[7] != CODEC_MSZH) ||
499 (avctx->codec_id == AV_CODEC_ID_ZLIB && avctx->extradata[7] != CODEC_ZLIB)) {
500 av_log(avctx, AV_LOG_ERROR, "Codec id and codec type mismatch. This should not happen.\n");
503 /* Detect image type */
504 switch (c->imgtype = avctx->extradata[4]) {
506 c->decomp_size = basesize * 3;
507 max_decomp_size = max_basesize * 3;
508 avctx->pix_fmt = AV_PIX_FMT_YUV444P;
509 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 1:1:1.\n");
512 c->decomp_size = basesize * 2;
513 max_decomp_size = max_basesize * 2;
514 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
515 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:2.\n");
518 c->decomp_size = basesize * 3;
519 max_decomp_size = max_basesize * 3;
520 avctx->pix_fmt = AV_PIX_FMT_BGR24;
521 av_log(avctx, AV_LOG_DEBUG, "Image type is RGB 24.\n");
524 c->decomp_size = basesize / 2 * 3;
525 max_decomp_size = max_basesize / 2 * 3;
526 avctx->pix_fmt = AV_PIX_FMT_YUV411P;
527 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:1:1.\n");
530 c->decomp_size = basesize * 2;
531 max_decomp_size = max_basesize * 2;
532 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
533 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 2:1:1.\n");
536 c->decomp_size = basesize / 2 * 3;
537 max_decomp_size = max_basesize / 2 * 3;
538 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
539 av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:0.\n");
542 av_log(avctx, AV_LOG_ERROR, "Unsupported image format %d.\n", c->imgtype);
543 return AVERROR_INVALIDDATA;
546 /* Detect compression method */
547 c->compression = (int8_t)avctx->extradata[5];
548 switch (avctx->codec_id) {
549 case AV_CODEC_ID_MSZH:
550 switch (c->compression) {
552 av_log(avctx, AV_LOG_DEBUG, "Compression enabled.\n");
554 case COMP_MSZH_NOCOMP:
556 av_log(avctx, AV_LOG_DEBUG, "No compression.\n");
559 av_log(avctx, AV_LOG_ERROR, "Unsupported compression format for MSZH (%d).\n", c->compression);
560 return AVERROR_INVALIDDATA;
563 #if CONFIG_ZLIB_DECODER
564 case AV_CODEC_ID_ZLIB:
565 switch (c->compression) {
566 case COMP_ZLIB_HISPEED:
567 av_log(avctx, AV_LOG_DEBUG, "High speed compression.\n");
569 case COMP_ZLIB_HICOMP:
570 av_log(avctx, AV_LOG_DEBUG, "High compression.\n");
572 case COMP_ZLIB_NORMAL:
573 av_log(avctx, AV_LOG_DEBUG, "Normal compression.\n");
576 if (c->compression < Z_NO_COMPRESSION || c->compression > Z_BEST_COMPRESSION) {
577 av_log(avctx, AV_LOG_ERROR, "Unsupported compression level for ZLIB: (%d).\n", c->compression);
578 return AVERROR_INVALIDDATA;
580 av_log(avctx, AV_LOG_DEBUG, "Compression level for ZLIB: (%d).\n", c->compression);
585 av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in compression switch.\n");
586 return AVERROR_INVALIDDATA;
589 /* Allocate decompression buffer */
590 if (c->decomp_size) {
591 if ((c->decomp_buf = av_malloc(max_decomp_size)) == NULL) {
592 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
593 return AVERROR(ENOMEM);
598 c->flags = avctx->extradata[6];
599 if (c->flags & FLAG_MULTITHREAD)
600 av_log(avctx, AV_LOG_DEBUG, "Multithread encoder flag set.\n");
601 if (c->flags & FLAG_NULLFRAME)
602 av_log(avctx, AV_LOG_DEBUG, "Nullframe insertion flag set.\n");
603 if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER))
604 av_log(avctx, AV_LOG_DEBUG, "PNG filter flag set.\n");
605 if (c->flags & FLAGMASK_UNUSED)
606 av_log(avctx, AV_LOG_ERROR, "Unknown flag set (%d).\n", c->flags);
608 /* If needed init zlib */
609 #if CONFIG_ZLIB_DECODER
610 if (avctx->codec_id == AV_CODEC_ID_ZLIB) {
612 c->zstream.zalloc = Z_NULL;
613 c->zstream.zfree = Z_NULL;
614 c->zstream.opaque = Z_NULL;
615 zret = inflateInit(&c->zstream);
617 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
618 av_freep(&c->decomp_buf);
619 return AVERROR_UNKNOWN;
632 static av_cold int decode_end(AVCodecContext *avctx)
634 LclDecContext * const c = avctx->priv_data;
636 av_freep(&c->decomp_buf);
638 avctx->release_buffer(avctx, &c->pic);
639 #if CONFIG_ZLIB_DECODER
640 if (avctx->codec_id == AV_CODEC_ID_ZLIB)
641 inflateEnd(&c->zstream);
647 #if CONFIG_MSZH_DECODER
648 AVCodec ff_mszh_decoder = {
650 .type = AVMEDIA_TYPE_VIDEO,
651 .id = AV_CODEC_ID_MSZH,
652 .priv_data_size = sizeof(LclDecContext),
655 .decode = decode_frame,
656 .capabilities = CODEC_CAP_DR1,
657 .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) MSZH"),
661 #if CONFIG_ZLIB_DECODER
662 AVCodec ff_zlib_decoder = {
664 .type = AVMEDIA_TYPE_VIDEO,
665 .id = AV_CODEC_ID_ZLIB,
666 .priv_data_size = sizeof(LclDecContext),
669 .decode = decode_frame,
670 .capabilities = CODEC_CAP_DR1,
671 .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),