1 /*
2 * Lagarith lossless decoder
3 * Copyright (c) 2009 Nathan Caldwell <saintdev (at) gmail.com>
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 * Lagarith lossless decoder
25 * @author Nathan Caldwell
26 */
27
28 #include <inttypes.h>
29
30 #include "avcodec.h"
31 #include "codec_internal.h"
32 #include "get_bits.h"
33 #include "mathops.h"
34 #include "lagarithrac.h"
35 #include "lossless_videodsp.h"
36 #include "thread.h"
37
38 enum LagarithFrameType {
39 FRAME_RAW = 1, /**< uncompressed */
40 FRAME_U_RGB24 = 2, /**< unaligned RGB24 */
41 FRAME_ARITH_YUY2 = 3, /**< arithmetic coded YUY2 */
42 FRAME_ARITH_RGB24 = 4, /**< arithmetic coded RGB24 */
43 FRAME_SOLID_GRAY = 5, /**< solid grayscale color frame */
44 FRAME_SOLID_COLOR = 6, /**< solid non-grayscale color frame */
45 FRAME_OLD_ARITH_RGB = 7, /**< obsolete arithmetic coded RGB (no longer encoded by upstream since version 1.1.0) */
46 FRAME_ARITH_RGBA = 8, /**< arithmetic coded RGBA */
47 FRAME_SOLID_RGBA = 9, /**< solid RGBA color frame */
48 FRAME_ARITH_YV12 = 10, /**< arithmetic coded YV12 */
49 FRAME_REDUCED_RES = 11, /**< reduced resolution YV12 frame */
50 };
51
52 typedef struct LagarithContext {
53 AVCodecContext *avctx;
54 LLVidDSPContext llviddsp;
55 int zeros; /**< number of consecutive zero bytes encountered */
56 int zeros_rem; /**< number of zero bytes remaining to output */
57 } LagarithContext;
58
59 /**
60 * Compute the 52-bit mantissa of 1/(double)denom.
61 * This crazy format uses floats in an entropy coder and we have to match x86
62 * rounding exactly, thus ordinary floats aren't portable enough.
63 * @param denom denominator
64 * @return 52-bit mantissa
65 * @see softfloat_mul
66 */
softfloat_reciprocal(uint32_t denom)67 static uint64_t softfloat_reciprocal(uint32_t denom)
68 {
69 int shift = av_log2(denom - 1) + 1;
70 uint64_t ret = (1ULL << 52) / denom;
71 uint64_t err = (1ULL << 52) - ret * denom;
72 ret <<= shift;
73 err <<= shift;
74 err += denom / 2;
75 return ret + err / denom;
76 }
77
78 /**
79 * (uint32_t)(x*f), where f has the given mantissa, and exponent 0
80 * Used in combination with softfloat_reciprocal computes x/(double)denom.
81 * @param x 32-bit integer factor
82 * @param mantissa mantissa of f with exponent 0
83 * @return 32-bit integer value (x*f)
84 * @see softfloat_reciprocal
85 */
softfloat_mul(uint32_t x, uint64_t mantissa)86 static uint32_t softfloat_mul(uint32_t x, uint64_t mantissa)
87 {
88 uint64_t l = x * (mantissa & 0xffffffff);
89 uint64_t h = x * (mantissa >> 32);
90 h += l >> 32;
91 l &= 0xffffffff;
92 l += 1LL << av_log2(h >> 21);
93 h += l >> 32;
94 return h >> 20;
95 }
96
lag_calc_zero_run(int8_t x)97 static uint8_t lag_calc_zero_run(int8_t x)
98 {
99 return (x * 2) ^ (x >> 7);
100 }
101
lag_decode_prob(GetBitContext *gb, uint32_t *value)102 static int lag_decode_prob(GetBitContext *gb, uint32_t *value)
103 {
104 static const uint8_t series[] = { 1, 2, 3, 5, 8, 13, 21 };
105 int i;
106 int bit = 0;
107 int bits = 0;
108 int prevbit = 0;
109 unsigned val;
110
111 for (i = 0; i < 7; i++) {
112 if (prevbit && bit)
113 break;
114 prevbit = bit;
115 bit = get_bits1(gb);
116 if (bit && !prevbit)
117 bits += series[i];
118 }
119 bits--;
120 if (bits < 0 || bits > 31) {
121 *value = 0;
122 return AVERROR_INVALIDDATA;
123 } else if (bits == 0) {
124 *value = 0;
125 return 0;
126 }
127
128 val = get_bits_long(gb, bits);
129 val |= 1U << bits;
130
131 *value = val - 1;
132
133 return 0;
134 }
135
lag_read_prob_header(lag_rac *rac, GetBitContext *gb)136 static int lag_read_prob_header(lag_rac *rac, GetBitContext *gb)
137 {
138 int i, j, scale_factor;
139 unsigned prob, cumulative_target;
140 unsigned cumul_prob = 0;
141 unsigned scaled_cumul_prob = 0;
142 int nnz = 0;
143
144 rac->prob[0] = 0;
145 rac->prob[257] = UINT_MAX;
146 /* Read probabilities from bitstream */
147 for (i = 1; i < 257; i++) {
148 if (lag_decode_prob(gb, &rac->prob[i]) < 0) {
149 av_log(rac->avctx, AV_LOG_ERROR, "Invalid probability encountered.\n");
150 return AVERROR_INVALIDDATA;
151 }
152 if ((uint64_t)cumul_prob + rac->prob[i] > UINT_MAX) {
153 av_log(rac->avctx, AV_LOG_ERROR, "Integer overflow encountered in cumulative probability calculation.\n");
154 return AVERROR_INVALIDDATA;
155 }
156 cumul_prob += rac->prob[i];
157 if (!rac->prob[i]) {
158 if (lag_decode_prob(gb, &prob)) {
159 av_log(rac->avctx, AV_LOG_ERROR, "Invalid probability run encountered.\n");
160 return AVERROR_INVALIDDATA;
161 }
162 if (prob > 256 - i)
163 prob = 256 - i;
164 for (j = 0; j < prob; j++)
165 rac->prob[++i] = 0;
166 }else {
167 nnz++;
168 }
169 }
170
171 if (!cumul_prob) {
172 av_log(rac->avctx, AV_LOG_ERROR, "All probabilities are 0!\n");
173 return AVERROR_INVALIDDATA;
174 }
175
176 if (nnz == 1 && (show_bits_long(gb, 32) & 0xFFFFFF)) {
177 return AVERROR_INVALIDDATA;
178 }
179
180 /* Scale probabilities so cumulative probability is an even power of 2. */
181 scale_factor = av_log2(cumul_prob);
182
183 if (cumul_prob & (cumul_prob - 1)) {
184 uint64_t mul = softfloat_reciprocal(cumul_prob);
185 for (i = 1; i <= 128; i++) {
186 rac->prob[i] = softfloat_mul(rac->prob[i], mul);
187 scaled_cumul_prob += rac->prob[i];
188 }
189 if (scaled_cumul_prob <= 0) {
190 av_log(rac->avctx, AV_LOG_ERROR, "Scaled probabilities invalid\n");
191 return AVERROR_INVALIDDATA;
192 }
193 for (; i < 257; i++) {
194 rac->prob[i] = softfloat_mul(rac->prob[i], mul);
195 scaled_cumul_prob += rac->prob[i];
196 }
197
198 scale_factor++;
199 if (scale_factor >= 32U)
200 return AVERROR_INVALIDDATA;
201 cumulative_target = 1U << scale_factor;
202
203 if (scaled_cumul_prob > cumulative_target) {
204 av_log(rac->avctx, AV_LOG_ERROR,
205 "Scaled probabilities are larger than target!\n");
206 return AVERROR_INVALIDDATA;
207 }
208
209 scaled_cumul_prob = cumulative_target - scaled_cumul_prob;
210
211 for (i = 1; scaled_cumul_prob; i = (i & 0x7f) + 1) {
212 if (rac->prob[i]) {
213 rac->prob[i]++;
214 scaled_cumul_prob--;
215 }
216 /* Comment from reference source:
217 * if (b & 0x80 == 0) { // order of operations is 'wrong'; it has been left this way
218 * // since the compression change is negligible and fixing it
219 * // breaks backwards compatibility
220 * b =- (signed int)b;
221 * b &= 0xFF;
222 * } else {
223 * b++;
224 * b &= 0x7f;
225 * }
226 */
227 }
228 }
229
230 if (scale_factor > 23)
231 return AVERROR_INVALIDDATA;
232
233 rac->scale = scale_factor;
234
235 /* Fill probability array with cumulative probability for each symbol. */
236 for (i = 1; i < 257; i++)
237 rac->prob[i] += rac->prob[i - 1];
238
239 return 0;
240 }
241
add_lag_median_prediction(uint8_t *dst, uint8_t *src1, uint8_t *diff, int w, int *left, int *left_top)242 static void add_lag_median_prediction(uint8_t *dst, uint8_t *src1,
243 uint8_t *diff, int w, int *left,
244 int *left_top)
245 {
246 /* This is almost identical to add_hfyu_median_pred in huffyuvdsp.h.
247 * However the &0xFF on the gradient predictor yields incorrect output
248 * for lagarith.
249 */
250 int i;
251 uint8_t l, lt;
252
253 l = *left;
254 lt = *left_top;
255
256 for (i = 0; i < w; i++) {
257 l = mid_pred(l, src1[i], l + src1[i] - lt) + diff[i];
258 lt = src1[i];
259 dst[i] = l;
260 }
261
262 *left = l;
263 *left_top = lt;
264 }
265
lag_pred_line(LagarithContext *l, uint8_t *buf, int width, int stride, int line)266 static void lag_pred_line(LagarithContext *l, uint8_t *buf,
267 int width, int stride, int line)
268 {
269 int L, TL;
270
271 if (!line) {
272 /* Left prediction only for first line */
273 L = l->llviddsp.add_left_pred(buf, buf, width, 0);
274 } else {
275 /* Left pixel is actually prev_row[width] */
276 L = buf[width - stride - 1];
277
278 if (line == 1) {
279 /* Second line, left predict first pixel, the rest of the line is median predicted
280 * NOTE: In the case of RGB this pixel is top predicted */
281 TL = l->avctx->pix_fmt == AV_PIX_FMT_YUV420P ? buf[-stride] : L;
282 } else {
283 /* Top left is 2 rows back, last pixel */
284 TL = buf[width - (2 * stride) - 1];
285 }
286
287 add_lag_median_prediction(buf, buf - stride, buf,
288 width, &L, &TL);
289 }
290 }
291
lag_pred_line_yuy2(LagarithContext *l, uint8_t *buf, int width, int stride, int line, int is_luma)292 static void lag_pred_line_yuy2(LagarithContext *l, uint8_t *buf,
293 int width, int stride, int line,
294 int is_luma)
295 {
296 int L, TL;
297
298 if (!line) {
299 L= buf[0];
300 if (is_luma)
301 buf[0] = 0;
302 l->llviddsp.add_left_pred(buf, buf, width, 0);
303 if (is_luma)
304 buf[0] = L;
305 return;
306 }
307 if (line == 1) {
308 const int HEAD = is_luma ? 4 : 2;
309 int i;
310
311 L = buf[width - stride - 1];
312 TL = buf[HEAD - stride - 1];
313 for (i = 0; i < HEAD; i++) {
314 L += buf[i];
315 buf[i] = L;
316 }
317 for (; i < width; i++) {
318 L = mid_pred(L & 0xFF, buf[i - stride], (L + buf[i - stride] - TL) & 0xFF) + buf[i];
319 TL = buf[i - stride];
320 buf[i] = L;
321 }
322 } else {
323 TL = buf[width - (2 * stride) - 1];
324 L = buf[width - stride - 1];
325 l->llviddsp.add_median_pred(buf, buf - stride, buf, width, &L, &TL);
326 }
327 }
328
lag_decode_line(LagarithContext *l, lag_rac *rac, uint8_t *dst, int width, int stride, int esc_count)329 static int lag_decode_line(LagarithContext *l, lag_rac *rac,
330 uint8_t *dst, int width, int stride,
331 int esc_count)
332 {
333 int i = 0;
334 int ret = 0;
335
336 if (!esc_count)
337 esc_count = -1;
338
339 /* Output any zeros remaining from the previous run */
340 handle_zeros:
341 if (l->zeros_rem) {
342 int count = FFMIN(l->zeros_rem, width - i);
343 memset(dst + i, 0, count);
344 i += count;
345 l->zeros_rem -= count;
346 }
347
348 while (i < width) {
349 dst[i] = lag_get_rac(rac);
350 ret++;
351
352 if (dst[i])
353 l->zeros = 0;
354 else
355 l->zeros++;
356
357 i++;
358 if (l->zeros == esc_count) {
359 int index = lag_get_rac(rac);
360 ret++;
361
362 l->zeros = 0;
363
364 l->zeros_rem = lag_calc_zero_run(index);
365 goto handle_zeros;
366 }
367 }
368 return ret;
369 }
370
lag_decode_zero_run_line(LagarithContext *l, uint8_t *dst, const uint8_t *src, const uint8_t *src_end, int width, int esc_count)371 static int lag_decode_zero_run_line(LagarithContext *l, uint8_t *dst,
372 const uint8_t *src, const uint8_t *src_end,
373 int width, int esc_count)
374 {
375 int i = 0;
376 int count;
377 uint8_t zero_run = 0;
378 const uint8_t *src_start = src;
379 uint8_t mask1 = -(esc_count < 2);
380 uint8_t mask2 = -(esc_count < 3);
381 uint8_t *end = dst + (width - 2);
382
383 avpriv_request_sample(l->avctx, "zero_run_line");
384
385 memset(dst, 0, width);
386
387 output_zeros:
388 if (l->zeros_rem) {
389 count = FFMIN(l->zeros_rem, width - i);
390 if (end - dst < count) {
391 av_log(l->avctx, AV_LOG_ERROR, "Too many zeros remaining.\n");
392 return AVERROR_INVALIDDATA;
393 }
394
395 memset(dst, 0, count);
396 l->zeros_rem -= count;
397 dst += count;
398 }
399
400 while (dst < end) {
401 i = 0;
402 while (!zero_run && dst + i < end) {
403 i++;
404 if (i+2 >= src_end - src)
405 return AVERROR_INVALIDDATA;
406 zero_run =
407 !(src[i] | (src[i + 1] & mask1) | (src[i + 2] & mask2));
408 }
409 if (zero_run) {
410 zero_run = 0;
411 i += esc_count;
412 if (i > end - dst ||
413 i >= src_end - src)
414 return AVERROR_INVALIDDATA;
415 memcpy(dst, src, i);
416 dst += i;
417 l->zeros_rem = lag_calc_zero_run(src[i]);
418
419 src += i + 1;
420 goto output_zeros;
421 } else {
422 memcpy(dst, src, i);
423 src += i;
424 dst += i;
425 }
426 }
427 return src - src_start;
428 }
429
430
431
lag_decode_arith_plane(LagarithContext *l, uint8_t *dst, int width, int height, int stride, const uint8_t *src, int src_size)432 static int lag_decode_arith_plane(LagarithContext *l, uint8_t *dst,
433 int width, int height, int stride,
434 const uint8_t *src, int src_size)
435 {
436 int i = 0;
437 int read = 0;
438 uint32_t length;
439 uint32_t offset = 1;
440 int esc_count;
441 GetBitContext gb;
442 lag_rac rac;
443 const uint8_t *src_end = src + src_size;
444 int ret;
445
446 rac.avctx = l->avctx;
447 l->zeros = 0;
448
449 if(src_size < 2)
450 return AVERROR_INVALIDDATA;
451
452 esc_count = src[0];
453 if (esc_count < 4) {
454 length = width * height;
455 if(src_size < 5)
456 return AVERROR_INVALIDDATA;
457 if (esc_count && AV_RL32(src + 1) < length) {
458 length = AV_RL32(src + 1);
459 offset += 4;
460 }
461
462 if ((ret = init_get_bits8(&gb, src + offset, src_size - offset)) < 0)
463 return ret;
464
465 if ((ret = lag_read_prob_header(&rac, &gb)) < 0)
466 return ret;
467
468 ff_lag_rac_init(&rac, &gb, length - stride);
469 for (i = 0; i < height; i++) {
470 if (rac.overread > MAX_OVERREAD)
471 return AVERROR_INVALIDDATA;
472 read += lag_decode_line(l, &rac, dst + (i * stride), width,
473 stride, esc_count);
474 }
475
476 if (read > length)
477 av_log(l->avctx, AV_LOG_WARNING,
478 "Output more bytes than length (%d of %"PRIu32")\n", read,
479 length);
480 } else if (esc_count < 8) {
481 esc_count -= 4;
482 src ++;
483 src_size --;
484 if (esc_count > 0) {
485 /* Zero run coding only, no range coding. */
486 for (i = 0; i < height; i++) {
487 int res = lag_decode_zero_run_line(l, dst + (i * stride), src,
488 src_end, width, esc_count);
489 if (res < 0)
490 return res;
491 src += res;
492 }
493 } else {
494 if (src_size < width * height)
495 return AVERROR_INVALIDDATA; // buffer not big enough
496 /* Plane is stored uncompressed */
497 for (i = 0; i < height; i++) {
498 memcpy(dst + (i * stride), src, width);
499 src += width;
500 }
501 }
502 } else if (esc_count == 0xff) {
503 /* Plane is a solid run of given value */
504 for (i = 0; i < height; i++)
505 memset(dst + i * stride, src[1], width);
506 /* Do not apply prediction.
507 Note: memset to 0 above, setting first value to src[1]
508 and applying prediction gives the same result. */
509 return 0;
510 } else {
511 av_log(l->avctx, AV_LOG_ERROR,
512 "Invalid zero run escape code! (%#x)\n", esc_count);
513 return AVERROR_INVALIDDATA;
514 }
515
516 if (l->avctx->pix_fmt != AV_PIX_FMT_YUV422P) {
517 for (i = 0; i < height; i++) {
518 lag_pred_line(l, dst, width, stride, i);
519 dst += stride;
520 }
521 } else {
522 for (i = 0; i < height; i++) {
523 lag_pred_line_yuy2(l, dst, width, stride, i,
524 width == l->avctx->width);
525 dst += stride;
526 }
527 }
528
529 return 0;
530 }
531
532 /**
533 * Decode a frame.
534 * @param avctx codec context
535 * @param data output AVFrame
536 * @param data_size size of output data or 0 if no picture is returned
537 * @param avpkt input packet
538 * @return number of consumed bytes on success or negative if decode fails
539 */
lag_decode_frame(AVCodecContext *avctx, AVFrame *p, int *got_frame, AVPacket *avpkt)540 static int lag_decode_frame(AVCodecContext *avctx, AVFrame *p,
541 int *got_frame, AVPacket *avpkt)
542 {
543 const uint8_t *buf = avpkt->data;
544 unsigned int buf_size = avpkt->size;
545 LagarithContext *l = avctx->priv_data;
546 uint8_t frametype;
547 uint32_t offset_gu = 0, offset_bv = 0, offset_ry = 9;
548 uint32_t offs[4];
549 uint8_t *srcs[4];
550 int i, j, planes = 3;
551 int ret = 0;
552
553 p->key_frame = 1;
554 p->pict_type = AV_PICTURE_TYPE_I;
555
556 frametype = buf[0];
557
558 offset_gu = AV_RL32(buf + 1);
559 offset_bv = AV_RL32(buf + 5);
560
561 switch (frametype) {
562 case FRAME_SOLID_RGBA:
563 avctx->pix_fmt = AV_PIX_FMT_GBRAP;
564 case FRAME_SOLID_GRAY:
565 if (frametype == FRAME_SOLID_GRAY)
566 if (avctx->bits_per_coded_sample == 24) {
567 avctx->pix_fmt = AV_PIX_FMT_GBRP;
568 } else {
569 avctx->pix_fmt = AV_PIX_FMT_GBRAP;
570 planes = 4;
571 }
572
573 if ((ret = ff_thread_get_buffer(avctx, p, 0)) < 0)
574 return ret;
575
576 if (frametype == FRAME_SOLID_RGBA) {
577 for (i = 0; i < avctx->height; i++) {
578 memset(p->data[0] + i * p->linesize[0], buf[2], avctx->width);
579 memset(p->data[1] + i * p->linesize[1], buf[1], avctx->width);
580 memset(p->data[2] + i * p->linesize[2], buf[3], avctx->width);
581 memset(p->data[3] + i * p->linesize[3], buf[4], avctx->width);
582 }
583 } else {
584 for (i = 0; i < avctx->height; i++) {
585 for (j = 0; j < planes; j++)
586 memset(p->data[j] + i * p->linesize[j], buf[1], avctx->width);
587 }
588 }
589 break;
590 case FRAME_SOLID_COLOR:
591 if (avctx->bits_per_coded_sample == 24) {
592 avctx->pix_fmt = AV_PIX_FMT_GBRP;
593 } else {
594 avctx->pix_fmt = AV_PIX_FMT_GBRAP;
595 }
596
597 if ((ret = ff_thread_get_buffer(avctx, p,0)) < 0)
598 return ret;
599
600 for (i = 0; i < avctx->height; i++) {
601 memset(p->data[0] + i * p->linesize[0], buf[2], avctx->width);
602 memset(p->data[1] + i * p->linesize[1], buf[1], avctx->width);
603 memset(p->data[2] + i * p->linesize[2], buf[3], avctx->width);
604 if (avctx->pix_fmt == AV_PIX_FMT_GBRAP)
605 memset(p->data[3] + i * p->linesize[3], 0xFFu, avctx->width);
606 }
607 break;
608 case FRAME_ARITH_RGBA:
609 avctx->pix_fmt = AV_PIX_FMT_GBRAP;
610 planes = 4;
611 offset_ry += 4;
612 offs[3] = AV_RL32(buf + 9);
613 case FRAME_ARITH_RGB24:
614 case FRAME_U_RGB24:
615 if (frametype == FRAME_ARITH_RGB24 || frametype == FRAME_U_RGB24)
616 avctx->pix_fmt = AV_PIX_FMT_GBRP;
617
618 if ((ret = ff_thread_get_buffer(avctx, p, 0)) < 0)
619 return ret;
620
621 offs[0] = offset_bv;
622 offs[1] = offset_gu;
623 offs[2] = offset_ry;
624
625 for (i = 0; i < planes; i++)
626 srcs[i] = p->data[i] + (avctx->height - 1) * p->linesize[i];
627 for (i = 0; i < planes; i++)
628 if (buf_size <= offs[i]) {
629 av_log(avctx, AV_LOG_ERROR,
630 "Invalid frame offsets\n");
631 return AVERROR_INVALIDDATA;
632 }
633
634 for (i = 0; i < planes; i++) {
635 ret = lag_decode_arith_plane(l, srcs[i],
636 avctx->width, avctx->height,
637 -p->linesize[i], buf + offs[i],
638 buf_size - offs[i]);
639 if (ret < 0)
640 return ret;
641 }
642 for (i = 0; i < avctx->height; i++) {
643 l->llviddsp.add_bytes(p->data[0] + i * p->linesize[0], p->data[1] + i * p->linesize[1], avctx->width);
644 l->llviddsp.add_bytes(p->data[2] + i * p->linesize[2], p->data[1] + i * p->linesize[1], avctx->width);
645 }
646 FFSWAP(uint8_t*, p->data[0], p->data[1]);
647 FFSWAP(int, p->linesize[0], p->linesize[1]);
648 FFSWAP(uint8_t*, p->data[2], p->data[1]);
649 FFSWAP(int, p->linesize[2], p->linesize[1]);
650 break;
651 case FRAME_ARITH_YUY2:
652 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
653
654 if ((ret = ff_thread_get_buffer(avctx, p, 0)) < 0)
655 return ret;
656
657 if (offset_ry >= buf_size ||
658 offset_gu >= buf_size ||
659 offset_bv >= buf_size) {
660 av_log(avctx, AV_LOG_ERROR,
661 "Invalid frame offsets\n");
662 return AVERROR_INVALIDDATA;
663 }
664
665 ret = lag_decode_arith_plane(l, p->data[0], avctx->width, avctx->height,
666 p->linesize[0], buf + offset_ry,
667 buf_size - offset_ry);
668 if (ret < 0)
669 return ret;
670 ret = lag_decode_arith_plane(l, p->data[1], (avctx->width + 1) / 2,
671 avctx->height, p->linesize[1],
672 buf + offset_gu, buf_size - offset_gu);
673 if (ret < 0)
674 return ret;
675 ret = lag_decode_arith_plane(l, p->data[2], (avctx->width + 1) / 2,
676 avctx->height, p->linesize[2],
677 buf + offset_bv, buf_size - offset_bv);
678 break;
679 case FRAME_ARITH_YV12:
680 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
681
682 if ((ret = ff_thread_get_buffer(avctx, p, 0)) < 0)
683 return ret;
684
685 if (offset_ry >= buf_size ||
686 offset_gu >= buf_size ||
687 offset_bv >= buf_size) {
688 av_log(avctx, AV_LOG_ERROR,
689 "Invalid frame offsets\n");
690 return AVERROR_INVALIDDATA;
691 }
692
693 ret = lag_decode_arith_plane(l, p->data[0], avctx->width, avctx->height,
694 p->linesize[0], buf + offset_ry,
695 buf_size - offset_ry);
696 if (ret < 0)
697 return ret;
698 ret = lag_decode_arith_plane(l, p->data[2], (avctx->width + 1) / 2,
699 (avctx->height + 1) / 2, p->linesize[2],
700 buf + offset_gu, buf_size - offset_gu);
701 if (ret < 0)
702 return ret;
703 ret = lag_decode_arith_plane(l, p->data[1], (avctx->width + 1) / 2,
704 (avctx->height + 1) / 2, p->linesize[1],
705 buf + offset_bv, buf_size - offset_bv);
706 break;
707 default:
708 av_log(avctx, AV_LOG_ERROR,
709 "Unsupported Lagarith frame type: %#"PRIx8"\n", frametype);
710 return AVERROR_PATCHWELCOME;
711 }
712
713 if (ret < 0)
714 return ret;
715
716 *got_frame = 1;
717
718 return buf_size;
719 }
720
lag_decode_init(AVCodecContext *avctx)721 static av_cold int lag_decode_init(AVCodecContext *avctx)
722 {
723 LagarithContext *l = avctx->priv_data;
724 l->avctx = avctx;
725
726 ff_llviddsp_init(&l->llviddsp);
727
728 return 0;
729 }
730
731 const FFCodec ff_lagarith_decoder = {
732 .p.name = "lagarith",
733 .p.long_name = NULL_IF_CONFIG_SMALL("Lagarith lossless"),
734 .p.type = AVMEDIA_TYPE_VIDEO,
735 .p.id = AV_CODEC_ID_LAGARITH,
736 .priv_data_size = sizeof(LagarithContext),
737 .init = lag_decode_init,
738 FF_CODEC_DECODE_CB(lag_decode_frame),
739 .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
740 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
741 };
742