7c65f14fc6a165ae536367f4a2479f39b2f2bc98
[libav.git] / libavcodec / mss2.c
1 /*
2 * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder
3 *
4 * This file is part of Libav.
5 *
6 * Libav is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * Libav is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with Libav; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 /**
22 * @file
23 * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder
24 */
25
26 #include "libavutil/avassert.h"
27 #include "internal.h"
28 #include "msmpeg4data.h"
29 #include "vc1.h"
30 #include "mss12.h"
31 #include "mss2dsp.h"
32
33 typedef struct MSS2Context {
34 VC1Context v;
35 int split_position;
36 AVFrame pic;
37 AVFrame last_pic;
38 MSS12Context c;
39 MSS2DSPContext dsp;
40 SliceContext sc[2];
41 } MSS2Context;
42
43 static void arith2_normalise(ArithCoder *c)
44 {
45 while ((c->high >> 15) - (c->low >> 15) < 2) {
46 if ((c->low ^ c->high) & 0x10000) {
47 c->high ^= 0x8000;
48 c->value ^= 0x8000;
49 c->low ^= 0x8000;
50 }
51 c->high = c->high << 8 & 0xFFFFFF | 0xFF;
52 c->value = c->value << 8 & 0xFFFFFF | bytestream2_get_byte(c->gbc.gB);
53 c->low = c->low << 8 & 0xFFFFFF;
54 }
55 }
56
57 ARITH_GET_BIT(2)
58
59 /* L. Stuiver and A. Moffat: "Piecewise Integer Mapping for Arithmetic Coding."
60 * In Proc. 8th Data Compression Conference (DCC '98), pp. 3-12, Mar. 1998 */
61
62 static int arith2_get_scaled_value(int value, int n, int range)
63 {
64 int split = (n << 1) - range;
65
66 if (value > split)
67 return split + (value - split >> 1);
68 else
69 return value;
70 }
71
72 static void arith2_rescale_interval(ArithCoder *c, int range,
73 int low, int high, int n)
74 {
75 int split = (n << 1) - range;
76
77 if (high > split)
78 c->high = split + (high - split << 1);
79 else
80 c->high = high;
81
82 c->high += c->low - 1;
83
84 if (low > split)
85 c->low += split + (low - split << 1);
86 else
87 c->low += low;
88 }
89
90 static int arith2_get_number(ArithCoder *c, int n)
91 {
92 int range = c->high - c->low + 1;
93 int scale = av_log2(range) - av_log2(n);
94 int val;
95
96 if (n << scale > range)
97 scale--;
98
99 n <<= scale;
100
101 val = arith2_get_scaled_value(c->value - c->low, n, range) >> scale;
102
103 arith2_rescale_interval(c, range, val << scale, (val + 1) << scale, n);
104
105 arith2_normalise(c);
106
107 return val;
108 }
109
110 static int arith2_get_prob(ArithCoder *c, int16_t *probs)
111 {
112 int range = c->high - c->low + 1, n = *probs;
113 int scale = av_log2(range) - av_log2(n);
114 int i = 0, val;
115
116 if (n << scale > range)
117 scale--;
118
119 n <<= scale;
120
121 val = arith2_get_scaled_value(c->value - c->low, n, range) >> scale;
122 while (probs[++i] > val) ;
123
124 arith2_rescale_interval(c, range,
125 probs[i] << scale, probs[i - 1] << scale, n);
126
127 return i;
128 }
129
130 ARITH_GET_MODEL_SYM(2)
131
132 static int arith2_get_consumed_bytes(ArithCoder *c)
133 {
134 int diff = (c->high >> 16) - (c->low >> 16);
135 int bp = bytestream2_tell(c->gbc.gB) - 3 << 3;
136 int bits = 1;
137
138 while (!(diff & 0x80)) {
139 bits++;
140 diff <<= 1;
141 }
142
143 return (bits + bp + 7 >> 3) + ((c->low >> 16) + 1 == c->high >> 16);
144 }
145
146 static void arith2_init(ArithCoder *c, GetByteContext *gB)
147 {
148 c->low = 0;
149 c->high = 0xFFFFFF;
150 c->value = bytestream2_get_be24(gB);
151 c->gbc.gB = gB;
152 c->get_model_sym = arith2_get_model_sym;
153 c->get_number = arith2_get_number;
154 }
155
156 static int decode_pal_v2(MSS12Context *ctx, const uint8_t *buf, int buf_size)
157 {
158 int i, ncol;
159 uint32_t *pal = ctx->pal + 256 - ctx->free_colours;
160
161 if (!ctx->free_colours)
162 return 0;
163
164 ncol = *buf++;
165 if (ncol > ctx->free_colours || buf_size < 2 + ncol * 3)
166 return -1;
167 for (i = 0; i < ncol; i++)
168 *pal++ = AV_RB24(buf + 3 * i);
169
170 return 1 + ncol * 3;
171 }
172
173 static int decode_555(GetByteContext *gB, uint16_t *dst, int stride,
174 int keyframe, int w, int h)
175 {
176 int last_symbol = 0, repeat = 0, prev_avail = 0;
177
178 if (!keyframe) {
179 int x, y, endx, endy, t;
180
181 #define READ_PAIR(a, b) \
182 a = bytestream2_get_byte(gB) << 4; \
183 t = bytestream2_get_byte(gB); \
184 a |= t >> 4; \
185 b = (t & 0xF) << 8; \
186 b |= bytestream2_get_byte(gB); \
187
188 READ_PAIR(x, endx)
189 READ_PAIR(y, endy)
190
191 if (endx >= w || endy >= h || x > endx || y > endy)
192 return -1;
193 dst += x + stride * y;
194 w = endx - x + 1;
195 h = endy - y + 1;
196 if (y)
197 prev_avail = 1;
198 }
199
200 do {
201 uint16_t *p = dst;
202 do {
203 if (repeat-- < 1) {
204 int b = bytestream2_get_byte(gB);
205 if (b < 128)
206 last_symbol = b << 8 | bytestream2_get_byte(gB);
207 else if (b > 129) {
208 repeat = 0;
209 while (b-- > 130)
210 repeat = (repeat << 8) + bytestream2_get_byte(gB) + 1;
211 if (last_symbol == -2) {
212 int skip = FFMIN((unsigned)repeat, dst + w - p);
213 repeat -= skip;
214 p += skip;
215 }
216 } else
217 last_symbol = 127 - b;
218 }
219 if (last_symbol >= 0)
220 *p = last_symbol;
221 else if (last_symbol == -1 && prev_avail)
222 *p = *(p - stride);
223 } while (++p < dst + w);
224 dst += stride;
225 prev_avail = 1;
226 } while (--h);
227
228 return 0;
229 }
230
231 static int decode_rle(GetBitContext *gb, uint8_t *pal_dst, int pal_stride,
232 uint8_t *rgb_dst, int rgb_stride, uint32_t *pal,
233 int keyframe, int kf_slipt, int slice, int w, int h)
234 {
235 uint8_t bits[270] = { 0 };
236 uint32_t codes[270];
237 VLC vlc;
238
239 int current_length = 0, read_codes = 0, next_code = 0, current_codes = 0;
240 int remaining_codes, surplus_codes, i;
241
242 const int alphabet_size = 270 - keyframe;
243
244 int last_symbol = 0, repeat = 0, prev_avail = 0;
245
246 if (!keyframe) {
247 int x, y, clipw, cliph;
248
249 x = get_bits(gb, 12);
250 y = get_bits(gb, 12);
251 clipw = get_bits(gb, 12) + 1;
252 cliph = get_bits(gb, 12) + 1;
253
254 if (x + clipw > w || y + cliph > h)
255 return AVERROR_INVALIDDATA;
256 pal_dst += pal_stride * y + x;
257 rgb_dst += rgb_stride * y + x * 3;
258 w = clipw;
259 h = cliph;
260 if (y)
261 prev_avail = 1;
262 } else {
263 if (slice > 0) {
264 pal_dst += pal_stride * kf_slipt;
265 rgb_dst += rgb_stride * kf_slipt;
266 prev_avail = 1;
267 h -= kf_slipt;
268 } else
269 h = kf_slipt;
270 }
271
272 /* read explicit codes */
273 do {
274 while (current_codes--) {
275 int symbol = get_bits(gb, 8);
276 if (symbol >= 204 - keyframe)
277 symbol += 14 - keyframe;
278 else if (symbol > 189)
279 symbol = get_bits1(gb) + (symbol << 1) - 190;
280 if (bits[symbol])
281 return AVERROR_INVALIDDATA;
282 bits[symbol] = current_length;
283 codes[symbol] = next_code++;
284 read_codes++;
285 }
286 current_length++;
287 next_code <<= 1;
288 remaining_codes = (1 << current_length) - next_code;
289 current_codes = get_bits(gb, av_ceil_log2(remaining_codes + 1));
290 if (current_length > 22 || current_codes > remaining_codes)
291 return AVERROR_INVALIDDATA;
292 } while (current_codes != remaining_codes);
293
294 remaining_codes = alphabet_size - read_codes;
295
296 /* determine the minimum length to fit the rest of the alphabet */
297 while ((surplus_codes = (2 << current_length) -
298 (next_code << 1) - remaining_codes) < 0) {
299 current_length++;
300 next_code <<= 1;
301 }
302
303 /* add the rest of the symbols lexicographically */
304 for (i = 0; i < alphabet_size; i++)
305 if (!bits[i]) {
306 if (surplus_codes-- == 0) {
307 current_length++;
308 next_code <<= 1;
309 }
310 bits[i] = current_length;
311 codes[i] = next_code++;
312 }
313
314 if (next_code != 1 << current_length)
315 return AVERROR_INVALIDDATA;
316
317 if (i = init_vlc(&vlc, 9, alphabet_size, bits, 1, 1, codes, 4, 4, 0))
318 return i;
319
320 /* frame decode */
321 do {
322 uint8_t *pp = pal_dst;
323 uint8_t *rp = rgb_dst;
324 do {
325 if (repeat-- < 1) {
326 int b = get_vlc2(gb, vlc.table, 9, 3);
327 if (b < 256)
328 last_symbol = b;
329 else if (b < 268) {
330 b -= 256;
331 if (b == 11)
332 b = get_bits(gb, 4) + 10;
333
334 if (!b)
335 repeat = 0;
336 else
337 repeat = get_bits(gb, b);
338
339 repeat += (1 << b) - 1;
340
341 if (last_symbol == -2) {
342 int skip = FFMIN(repeat, pal_dst + w - pp);
343 repeat -= skip;
344 pp += skip;
345 rp += skip * 3;
346 }
347 } else
348 last_symbol = 267 - b;
349 }
350 if (last_symbol >= 0) {
351 *pp = last_symbol;
352 AV_WB24(rp, pal[last_symbol]);
353 } else if (last_symbol == -1 && prev_avail) {
354 *pp = *(pp - pal_stride);
355 memcpy(rp, rp - rgb_stride, 3);
356 }
357 rp += 3;
358 } while (++pp < pal_dst + w);
359 pal_dst += pal_stride;
360 rgb_dst += rgb_stride;
361 prev_avail = 1;
362 } while (--h);
363
364 ff_free_vlc(&vlc);
365 return 0;
366 }
367
368 static int decode_wmv9(AVCodecContext *avctx, const uint8_t *buf, int buf_size,
369 int x, int y, int w, int h, int wmv9_mask)
370 {
371 MSS2Context *ctx = avctx->priv_data;
372 MSS12Context *c = &ctx->c;
373 VC1Context *v = avctx->priv_data;
374 MpegEncContext *s = &v->s;
375 AVFrame *f;
376
377 ff_mpeg_flush(avctx);
378
379 if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
380 int i = ff_find_unused_picture(s, 0);
381 if (i < 0)
382 return -1;
383 s->current_picture_ptr = &s->picture[i];
384 }
385
386 init_get_bits(&s->gb, buf, buf_size * 8);
387
388 s->loop_filter = avctx->skip_loop_filter < AVDISCARD_ALL;
389
390 if (ff_vc1_parse_frame_header(v, &s->gb) == -1) {
391 av_log(v->s.avctx, AV_LOG_ERROR, "header error\n");
392 return AVERROR_INVALIDDATA;
393 }
394
395 if (s->pict_type != AV_PICTURE_TYPE_I) {
396 av_log(v->s.avctx, AV_LOG_ERROR, "expected I-frame\n");
397 return AVERROR_INVALIDDATA;
398 }
399
400 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
401
402 if (ff_MPV_frame_start(s, avctx) < 0) {
403 av_log(v->s.avctx, AV_LOG_ERROR, "ff_MPV_frame_start error\n");
404 avctx->pix_fmt = AV_PIX_FMT_RGB24;
405 return -1;
406 }
407
408 ff_er_frame_start(s);
409
410 v->bits = buf_size * 8;
411
412 v->end_mb_x = (w + 15) >> 4;
413 s->end_mb_y = (h + 15) >> 4;
414 if (v->respic & 1)
415 v->end_mb_x = v->end_mb_x + 1 >> 1;
416 if (v->respic & 2)
417 s->end_mb_y = s->end_mb_y + 1 >> 1;
418
419 ff_vc1_decode_blocks(v);
420
421 ff_er_frame_end(s);
422
423 ff_MPV_frame_end(s);
424
425 f = &s->current_picture.f;
426
427 if (v->respic == 3) {
428 ctx->dsp.upsample_plane(f->data[0], f->linesize[0], w, h);
429 ctx->dsp.upsample_plane(f->data[1], f->linesize[1], w >> 1, h >> 1);
430 ctx->dsp.upsample_plane(f->data[2], f->linesize[2], w >> 1, h >> 1);
431 } else if (v->respic)
432 av_log_ask_for_sample(v->s.avctx,
433 "Asymmetric WMV9 rectangle subsampling\n");
434
435 av_assert0(f->linesize[1] == f->linesize[2]);
436
437 if (wmv9_mask != -1)
438 ctx->dsp.mss2_blit_wmv9_masked(c->rgb_pic + y * c->rgb_stride + x * 3,
439 c->rgb_stride, wmv9_mask,
440 c->pal_pic + y * c->pal_stride + x,
441 c->pal_stride,
442 f->data[0], f->linesize[0],
443 f->data[1], f->data[2], f->linesize[1],
444 w, h);
445 else
446 ctx->dsp.mss2_blit_wmv9(c->rgb_pic + y * c->rgb_stride + x * 3,
447 c->rgb_stride,
448 f->data[0], f->linesize[0],
449 f->data[1], f->data[2], f->linesize[1],
450 w, h);
451
452 avctx->pix_fmt = AV_PIX_FMT_RGB24;
453
454 return 0;
455 }
456
457 typedef struct Rectangle {
458 int coded, x, y, w, h;
459 } Rectangle;
460
461 #define MAX_WMV9_RECTANGLES 20
462 #define ARITH2_PADDING 2
463
464 static int mss2_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
465 AVPacket *avpkt)
466 {
467 const uint8_t *buf = avpkt->data;
468 int buf_size = avpkt->size;
469 MSS2Context *ctx = avctx->priv_data;
470 MSS12Context *c = &ctx->c;
471 GetBitContext gb;
472 GetByteContext gB;
473 ArithCoder acoder;
474
475 int keyframe, has_wmv9, has_mv, is_rle, is_555, ret;
476
477 Rectangle wmv9rects[MAX_WMV9_RECTANGLES], *r;
478 int used_rects = 0, i, implicit_rect = 0, av_uninit(wmv9_mask);
479
480 av_assert0(FF_INPUT_BUFFER_PADDING_SIZE >=
481 ARITH2_PADDING + (MIN_CACHE_BITS + 7) / 8);
482
483 init_get_bits(&gb, buf, buf_size * 8);
484
485 if (keyframe = get_bits1(&gb))
486 skip_bits(&gb, 7);
487 has_wmv9 = get_bits1(&gb);
488 has_mv = keyframe ? 0 : get_bits1(&gb);
489 is_rle = get_bits1(&gb);
490 is_555 = is_rle && get_bits1(&gb);
491 if (c->slice_split > 0)
492 ctx->split_position = c->slice_split;
493 else if (c->slice_split < 0) {
494 if (get_bits1(&gb)) {
495 if (get_bits1(&gb)) {
496 if (get_bits1(&gb))
497 ctx->split_position = get_bits(&gb, 16);
498 else
499 ctx->split_position = get_bits(&gb, 12);
500 } else
501 ctx->split_position = get_bits(&gb, 8) << 4;
502 } else {
503 if (keyframe)
504 ctx->split_position = avctx->height / 2;
505 }
506 } else
507 ctx->split_position = avctx->height;
508
509 if (c->slice_split && (ctx->split_position < 1 - is_555 ||
510 ctx->split_position > avctx->height - 1))
511 return AVERROR_INVALIDDATA;
512
513 align_get_bits(&gb);
514 buf += get_bits_count(&gb) >> 3;
515 buf_size -= get_bits_count(&gb) >> 3;
516
517 if (buf_size < 1)
518 return AVERROR_INVALIDDATA;
519
520 if (is_555 && (has_wmv9 || has_mv || c->slice_split && ctx->split_position))
521 return AVERROR_INVALIDDATA;
522
523 avctx->pix_fmt = is_555 ? AV_PIX_FMT_RGB555 : AV_PIX_FMT_RGB24;
524 if (ctx->pic.data[0] && ctx->pic.format != avctx->pix_fmt)
525 avctx->release_buffer(avctx, &ctx->pic);
526
527 if (has_wmv9) {
528 bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
529 arith2_init(&acoder, &gB);
530
531 implicit_rect = !arith2_get_bit(&acoder);
532
533 while (arith2_get_bit(&acoder)) {
534 if (used_rects == MAX_WMV9_RECTANGLES)
535 return AVERROR_INVALIDDATA;
536 r = &wmv9rects[used_rects];
537 if (!used_rects)
538 r->x = arith2_get_number(&acoder, avctx->width);
539 else
540 r->x = arith2_get_number(&acoder, avctx->width -
541 wmv9rects[used_rects - 1].x) +
542 wmv9rects[used_rects - 1].x;
543 r->y = arith2_get_number(&acoder, avctx->height);
544 r->w = arith2_get_number(&acoder, avctx->width - r->x) + 1;
545 r->h = arith2_get_number(&acoder, avctx->height - r->y) + 1;
546 used_rects++;
547 }
548
549 if (implicit_rect && used_rects) {
550 av_log(avctx, AV_LOG_ERROR, "implicit_rect && used_rects > 0\n");
551 return AVERROR_INVALIDDATA;
552 }
553
554 if (implicit_rect) {
555 wmv9rects[0].x = 0;
556 wmv9rects[0].y = 0;
557 wmv9rects[0].w = avctx->width;
558 wmv9rects[0].h = avctx->height;
559
560 used_rects = 1;
561 }
562 for (i = 0; i < used_rects; i++) {
563 if (!implicit_rect && arith2_get_bit(&acoder)) {
564 av_log(avctx, AV_LOG_ERROR, "Unexpected grandchildren\n");
565 return AVERROR_INVALIDDATA;
566 }
567 if (!i) {
568 wmv9_mask = arith2_get_bit(&acoder) - 1;
569 if (!wmv9_mask)
570 wmv9_mask = arith2_get_number(&acoder, 256);
571 }
572 wmv9rects[i].coded = arith2_get_number(&acoder, 2);
573 }
574
575 buf += arith2_get_consumed_bytes(&acoder);
576 buf_size -= arith2_get_consumed_bytes(&acoder);
577 if (buf_size < 1)
578 return AVERROR_INVALIDDATA;
579 }
580
581 c->mvX = c->mvY = 0;
582 if (keyframe && !is_555) {
583 if ((i = decode_pal_v2(c, buf, buf_size)) < 0)
584 return AVERROR_INVALIDDATA;
585 buf += i;
586 buf_size -= i;
587 } else if (has_mv) {
588 buf += 4;
589 buf_size -= 4;
590 if (buf_size < 1)
591 return AVERROR_INVALIDDATA;
592 c->mvX = AV_RB16(buf - 4) - avctx->width;
593 c->mvY = AV_RB16(buf - 2) - avctx->height;
594 }
595
596 if (c->mvX < 0 || c->mvY < 0) {
597 FFSWAP(AVFrame, ctx->pic, ctx->last_pic);
598 FFSWAP(uint8_t *, c->pal_pic, c->last_pal_pic);
599
600 if (ctx->pic.data[0])
601 avctx->release_buffer(avctx, &ctx->pic);
602
603 ctx->pic.reference = 3;
604 ctx->pic.buffer_hints = FF_BUFFER_HINTS_VALID |
605 FF_BUFFER_HINTS_READABLE |
606 FF_BUFFER_HINTS_PRESERVE |
607 FF_BUFFER_HINTS_REUSABLE;
608
609 if ((ret = ff_get_buffer(avctx, &ctx->pic)) < 0) {
610 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
611 return ret;
612 }
613
614 if (ctx->last_pic.data[0]) {
615 av_assert0(ctx->pic.linesize[0] == ctx->last_pic.linesize[0]);
616 c->last_rgb_pic = ctx->last_pic.data[0] +
617 ctx->last_pic.linesize[0] * (avctx->height - 1);
618 } else {
619 av_log(avctx, AV_LOG_ERROR, "Missing keyframe\n");
620 return -1;
621 }
622 } else {
623 if (ctx->last_pic.data[0])
624 avctx->release_buffer(avctx, &ctx->last_pic);
625
626 ctx->pic.reference = 3;
627 ctx->pic.buffer_hints = FF_BUFFER_HINTS_VALID |
628 FF_BUFFER_HINTS_READABLE |
629 FF_BUFFER_HINTS_PRESERVE |
630 FF_BUFFER_HINTS_REUSABLE;
631
632 if ((ret = avctx->reget_buffer(avctx, &ctx->pic)) < 0) {
633 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
634 return ret;
635 }
636
637 c->last_rgb_pic = NULL;
638 }
639 c->rgb_pic = ctx->pic.data[0] +
640 ctx->pic.linesize[0] * (avctx->height - 1);
641 c->rgb_stride = -ctx->pic.linesize[0];
642
643 ctx->pic.key_frame = keyframe;
644 ctx->pic.pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
645
646 if (is_555) {
647 bytestream2_init(&gB, buf, buf_size);
648
649 if (decode_555(&gB, (uint16_t *)c->rgb_pic, c->rgb_stride >> 1,
650 keyframe, avctx->width, avctx->height))
651 return AVERROR_INVALIDDATA;
652
653 buf_size -= bytestream2_tell(&gB);
654 } else {
655 if (keyframe) {
656 c->corrupted = 0;
657 ff_mss12_slicecontext_reset(&ctx->sc[0]);
658 if (c->slice_split)
659 ff_mss12_slicecontext_reset(&ctx->sc[1]);
660 }
661 if (is_rle) {
662 init_get_bits(&gb, buf, buf_size * 8);
663 if (ret = decode_rle(&gb, c->pal_pic, c->pal_stride,
664 c->rgb_pic, c->rgb_stride, c->pal, keyframe,
665 ctx->split_position, 0,
666 avctx->width, avctx->height))
667 return ret;
668 align_get_bits(&gb);
669
670 if (c->slice_split)
671 if (ret = decode_rle(&gb, c->pal_pic, c->pal_stride,
672 c->rgb_pic, c->rgb_stride, c->pal, keyframe,
673 ctx->split_position, 1,
674 avctx->width, avctx->height))
675 return ret;
676
677 align_get_bits(&gb);
678 buf += get_bits_count(&gb) >> 3;
679 buf_size -= get_bits_count(&gb) >> 3;
680 } else if (!implicit_rect || wmv9_mask != -1) {
681 if (c->corrupted)
682 return AVERROR_INVALIDDATA;
683 bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
684 arith2_init(&acoder, &gB);
685 c->keyframe = keyframe;
686 if (c->corrupted = ff_mss12_decode_rect(&ctx->sc[0], &acoder, 0, 0,
687 avctx->width,
688 ctx->split_position))
689 return AVERROR_INVALIDDATA;
690
691 buf += arith2_get_consumed_bytes(&acoder);
692 buf_size -= arith2_get_consumed_bytes(&acoder);
693 if (c->slice_split) {
694 if (buf_size < 1)
695 return AVERROR_INVALIDDATA;
696 bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
697 arith2_init(&acoder, &gB);
698 if (c->corrupted = ff_mss12_decode_rect(&ctx->sc[1], &acoder, 0,
699 ctx->split_position,
700 avctx->width,
701 avctx->height - ctx->split_position))
702 return AVERROR_INVALIDDATA;
703
704 buf += arith2_get_consumed_bytes(&acoder);
705 buf_size -= arith2_get_consumed_bytes(&acoder);
706 }
707 } else
708 memset(c->pal_pic, 0, c->pal_stride * avctx->height);
709 }
710
711 if (has_wmv9) {
712 for (i = 0; i < used_rects; i++) {
713 int x = wmv9rects[i].x;
714 int y = wmv9rects[i].y;
715 int w = wmv9rects[i].w;
716 int h = wmv9rects[i].h;
717 if (wmv9rects[i].coded) {
718 int WMV9codedFrameSize;
719 if (buf_size < 4 || !(WMV9codedFrameSize = AV_RL24(buf)))
720 return AVERROR_INVALIDDATA;
721 if (ret = decode_wmv9(avctx, buf + 3, buf_size - 3,
722 x, y, w, h, wmv9_mask))
723 return ret;
724 buf += WMV9codedFrameSize + 3;
725 buf_size -= WMV9codedFrameSize + 3;
726 } else {
727 uint8_t *dst = c->rgb_pic + y * c->rgb_stride + x * 3;
728 if (wmv9_mask != -1) {
729 ctx->dsp.mss2_gray_fill_masked(dst, c->rgb_stride,
730 wmv9_mask,
731 c->pal_pic + y * c->pal_stride + x,
732 c->pal_stride,
733 w, h);
734 } else {
735 do {
736 memset(dst, 0x80, w * 3);
737 dst += c->rgb_stride;
738 } while (--h);
739 }
740 }
741 }
742 }
743
744 if (buf_size)
745 av_log(avctx, AV_LOG_WARNING, "buffer not fully consumed\n");
746
747 *data_size = sizeof(AVFrame);
748 *(AVFrame *)data = ctx->pic;
749
750 return avpkt->size;
751 }
752
753 static av_cold int wmv9_init(AVCodecContext *avctx)
754 {
755 VC1Context *v = avctx->priv_data;
756
757 v->s.avctx = avctx;
758 avctx->flags |= CODEC_FLAG_EMU_EDGE;
759 v->s.flags |= CODEC_FLAG_EMU_EDGE;
760
761 if (avctx->idct_algo == FF_IDCT_AUTO)
762 avctx->idct_algo = FF_IDCT_WMV2;
763
764 if (ff_vc1_init_common(v) < 0)
765 return -1;
766 ff_vc1dsp_init(&v->vc1dsp);
767
768 v->profile = PROFILE_MAIN;
769
770 v->zz_8x4 = ff_wmv2_scantableA;
771 v->zz_4x8 = ff_wmv2_scantableB;
772 v->res_y411 = 0;
773 v->res_sprite = 0;
774
775 v->frmrtq_postproc = 7;
776 v->bitrtq_postproc = 31;
777
778 v->res_x8 = 0;
779 v->multires = 0;
780 v->res_fasttx = 1;
781
782 v->fastuvmc = 0;
783
784 v->extended_mv = 0;
785
786 v->dquant = 1;
787 v->vstransform = 1;
788
789 v->res_transtab = 0;
790
791 v->overlap = 0;
792
793 v->s.resync_marker = 0;
794 v->rangered = 0;
795
796 v->s.max_b_frames = avctx->max_b_frames = 0;
797 v->quantizer_mode = 0;
798
799 v->finterpflag = 0;
800
801 v->res_rtm_flag = 1;
802
803 ff_vc1_init_transposed_scantables(v);
804
805 if (ff_msmpeg4_decode_init(avctx) < 0 ||
806 ff_vc1_decode_init_alloc_tables(v) < 0)
807 return -1;
808
809 /* error concealment */
810 v->s.me.qpel_put = v->s.dsp.put_qpel_pixels_tab;
811 v->s.me.qpel_avg = v->s.dsp.avg_qpel_pixels_tab;
812
813 return 0;
814 }
815
816 static av_cold int mss2_decode_end(AVCodecContext *avctx)
817 {
818 MSS2Context *const ctx = avctx->priv_data;
819
820 if (ctx->pic.data[0])
821 avctx->release_buffer(avctx, &ctx->pic);
822 if (ctx->last_pic.data[0])
823 avctx->release_buffer(avctx, &ctx->last_pic);
824
825 ff_mss12_decode_end(&ctx->c);
826 av_freep(&ctx->c.pal_pic);
827 av_freep(&ctx->c.last_pal_pic);
828 ff_vc1_decode_end(avctx);
829
830 return 0;
831 }
832
833 static av_cold int mss2_decode_init(AVCodecContext *avctx)
834 {
835 MSS2Context * const ctx = avctx->priv_data;
836 MSS12Context *c = &ctx->c;
837 int ret;
838 c->avctx = avctx;
839 avctx->coded_frame = &ctx->pic;
840 if (ret = ff_mss12_decode_init(c, 1, &ctx->sc[0], &ctx->sc[1]))
841 return ret;
842 c->pal_stride = c->mask_stride;
843 c->pal_pic = av_mallocz(c->pal_stride * avctx->height);
844 c->last_pal_pic = av_mallocz(c->pal_stride * avctx->height);
845 if (!c->pal_pic || !c->last_pal_pic) {
846 mss2_decode_end(avctx);
847 return AVERROR(ENOMEM);
848 }
849 if (ret = wmv9_init(avctx)) {
850 mss2_decode_end(avctx);
851 return ret;
852 }
853 ff_mss2dsp_init(&ctx->dsp);
854
855 avctx->pix_fmt = c->free_colours == 127 ? AV_PIX_FMT_RGB555
856 : AV_PIX_FMT_RGB24;
857
858 return 0;
859 }
860
861 AVCodec ff_mss2_decoder = {
862 .name = "mss2",
863 .type = AVMEDIA_TYPE_VIDEO,
864 .id = AV_CODEC_ID_MSS2,
865 .priv_data_size = sizeof(MSS2Context),
866 .init = mss2_decode_init,
867 .close = mss2_decode_end,
868 .decode = mss2_decode_frame,
869 .capabilities = CODEC_CAP_DR1,
870 .long_name = NULL_IF_CONFIG_SMALL("MS Windows Media Video V9 Screen"),
871 };