006432b17b2a75067395d51d0e5336b315d23e89
[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 AVERROR_INVALIDDATA;
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 AVERROR_INVALIDDATA;
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 int ret;
377
378 ff_mpeg_flush(avctx);
379
380 if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
381 int i = ff_find_unused_picture(s, 0);
382 if (i < 0)
383 return i;
384 s->current_picture_ptr = &s->picture[i];
385 }
386
387 init_get_bits(&s->gb, buf, buf_size * 8);
388
389 s->loop_filter = avctx->skip_loop_filter < AVDISCARD_ALL;
390
391 if (ff_vc1_parse_frame_header(v, &s->gb) == -1) {
392 av_log(v->s.avctx, AV_LOG_ERROR, "header error\n");
393 return AVERROR_INVALIDDATA;
394 }
395
396 if (s->pict_type != AV_PICTURE_TYPE_I) {
397 av_log(v->s.avctx, AV_LOG_ERROR, "expected I-frame\n");
398 return AVERROR_INVALIDDATA;
399 }
400
401 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
402
403 if ((ret = ff_MPV_frame_start(s, avctx)) < 0) {
404 av_log(v->s.avctx, AV_LOG_ERROR, "ff_MPV_frame_start error\n");
405 avctx->pix_fmt = AV_PIX_FMT_RGB24;
406 return ret;
407 }
408
409 ff_mpeg_er_frame_start(s);
410
411 v->bits = buf_size * 8;
412
413 v->end_mb_x = (w + 15) >> 4;
414 s->end_mb_y = (h + 15) >> 4;
415 if (v->respic & 1)
416 v->end_mb_x = v->end_mb_x + 1 >> 1;
417 if (v->respic & 2)
418 s->end_mb_y = s->end_mb_y + 1 >> 1;
419
420 ff_vc1_decode_blocks(v);
421
422 ff_er_frame_end(&s->er);
423
424 ff_MPV_frame_end(s);
425
426 f = &s->current_picture.f;
427
428 if (v->respic == 3) {
429 ctx->dsp.upsample_plane(f->data[0], f->linesize[0], w, h);
430 ctx->dsp.upsample_plane(f->data[1], f->linesize[1], w >> 1, h >> 1);
431 ctx->dsp.upsample_plane(f->data[2], f->linesize[2], w >> 1, h >> 1);
432 } else if (v->respic)
433 av_log_ask_for_sample(v->s.avctx,
434 "Asymmetric WMV9 rectangle subsampling\n");
435
436 av_assert0(f->linesize[1] == f->linesize[2]);
437
438 if (wmv9_mask != -1)
439 ctx->dsp.mss2_blit_wmv9_masked(c->rgb_pic + y * c->rgb_stride + x * 3,
440 c->rgb_stride, wmv9_mask,
441 c->pal_pic + y * c->pal_stride + x,
442 c->pal_stride,
443 f->data[0], f->linesize[0],
444 f->data[1], f->data[2], f->linesize[1],
445 w, h);
446 else
447 ctx->dsp.mss2_blit_wmv9(c->rgb_pic + y * c->rgb_stride + x * 3,
448 c->rgb_stride,
449 f->data[0], f->linesize[0],
450 f->data[1], f->data[2], f->linesize[1],
451 w, h);
452
453 avctx->pix_fmt = AV_PIX_FMT_RGB24;
454
455 return 0;
456 }
457
458 typedef struct Rectangle {
459 int coded, x, y, w, h;
460 } Rectangle;
461
462 #define MAX_WMV9_RECTANGLES 20
463 #define ARITH2_PADDING 2
464
465 static int mss2_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
466 AVPacket *avpkt)
467 {
468 const uint8_t *buf = avpkt->data;
469 int buf_size = avpkt->size;
470 MSS2Context *ctx = avctx->priv_data;
471 MSS12Context *c = &ctx->c;
472 GetBitContext gb;
473 GetByteContext gB;
474 ArithCoder acoder;
475
476 int keyframe, has_wmv9, has_mv, is_rle, is_555, ret;
477
478 Rectangle wmv9rects[MAX_WMV9_RECTANGLES], *r;
479 int used_rects = 0, i, implicit_rect = 0, av_uninit(wmv9_mask);
480
481 av_assert0(FF_INPUT_BUFFER_PADDING_SIZE >=
482 ARITH2_PADDING + (MIN_CACHE_BITS + 7) / 8);
483
484 init_get_bits(&gb, buf, buf_size * 8);
485
486 if (keyframe = get_bits1(&gb))
487 skip_bits(&gb, 7);
488 has_wmv9 = get_bits1(&gb);
489 has_mv = keyframe ? 0 : get_bits1(&gb);
490 is_rle = get_bits1(&gb);
491 is_555 = is_rle && get_bits1(&gb);
492 if (c->slice_split > 0)
493 ctx->split_position = c->slice_split;
494 else if (c->slice_split < 0) {
495 if (get_bits1(&gb)) {
496 if (get_bits1(&gb)) {
497 if (get_bits1(&gb))
498 ctx->split_position = get_bits(&gb, 16);
499 else
500 ctx->split_position = get_bits(&gb, 12);
501 } else
502 ctx->split_position = get_bits(&gb, 8) << 4;
503 } else {
504 if (keyframe)
505 ctx->split_position = avctx->height / 2;
506 }
507 } else
508 ctx->split_position = avctx->height;
509
510 if (c->slice_split && (ctx->split_position < 1 - is_555 ||
511 ctx->split_position > avctx->height - 1))
512 return AVERROR_INVALIDDATA;
513
514 align_get_bits(&gb);
515 buf += get_bits_count(&gb) >> 3;
516 buf_size -= get_bits_count(&gb) >> 3;
517
518 if (buf_size < 1)
519 return AVERROR_INVALIDDATA;
520
521 if (is_555 && (has_wmv9 || has_mv || c->slice_split && ctx->split_position))
522 return AVERROR_INVALIDDATA;
523
524 avctx->pix_fmt = is_555 ? AV_PIX_FMT_RGB555 : AV_PIX_FMT_RGB24;
525 if (ctx->pic.data[0] && ctx->pic.format != avctx->pix_fmt)
526 avctx->release_buffer(avctx, &ctx->pic);
527
528 if (has_wmv9) {
529 bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
530 arith2_init(&acoder, &gB);
531
532 implicit_rect = !arith2_get_bit(&acoder);
533
534 while (arith2_get_bit(&acoder)) {
535 if (used_rects == MAX_WMV9_RECTANGLES)
536 return AVERROR_INVALIDDATA;
537 r = &wmv9rects[used_rects];
538 if (!used_rects)
539 r->x = arith2_get_number(&acoder, avctx->width);
540 else
541 r->x = arith2_get_number(&acoder, avctx->width -
542 wmv9rects[used_rects - 1].x) +
543 wmv9rects[used_rects - 1].x;
544 r->y = arith2_get_number(&acoder, avctx->height);
545 r->w = arith2_get_number(&acoder, avctx->width - r->x) + 1;
546 r->h = arith2_get_number(&acoder, avctx->height - r->y) + 1;
547 used_rects++;
548 }
549
550 if (implicit_rect && used_rects) {
551 av_log(avctx, AV_LOG_ERROR, "implicit_rect && used_rects > 0\n");
552 return AVERROR_INVALIDDATA;
553 }
554
555 if (implicit_rect) {
556 wmv9rects[0].x = 0;
557 wmv9rects[0].y = 0;
558 wmv9rects[0].w = avctx->width;
559 wmv9rects[0].h = avctx->height;
560
561 used_rects = 1;
562 }
563 for (i = 0; i < used_rects; i++) {
564 if (!implicit_rect && arith2_get_bit(&acoder)) {
565 av_log(avctx, AV_LOG_ERROR, "Unexpected grandchildren\n");
566 return AVERROR_INVALIDDATA;
567 }
568 if (!i) {
569 wmv9_mask = arith2_get_bit(&acoder) - 1;
570 if (!wmv9_mask)
571 wmv9_mask = arith2_get_number(&acoder, 256);
572 }
573 wmv9rects[i].coded = arith2_get_number(&acoder, 2);
574 }
575
576 buf += arith2_get_consumed_bytes(&acoder);
577 buf_size -= arith2_get_consumed_bytes(&acoder);
578 if (buf_size < 1)
579 return AVERROR_INVALIDDATA;
580 }
581
582 c->mvX = c->mvY = 0;
583 if (keyframe && !is_555) {
584 if ((i = decode_pal_v2(c, buf, buf_size)) < 0)
585 return AVERROR_INVALIDDATA;
586 buf += i;
587 buf_size -= i;
588 } else if (has_mv) {
589 buf += 4;
590 buf_size -= 4;
591 if (buf_size < 1)
592 return AVERROR_INVALIDDATA;
593 c->mvX = AV_RB16(buf - 4) - avctx->width;
594 c->mvY = AV_RB16(buf - 2) - avctx->height;
595 }
596
597 if (c->mvX < 0 || c->mvY < 0) {
598 FFSWAP(AVFrame, ctx->pic, ctx->last_pic);
599 FFSWAP(uint8_t *, c->pal_pic, c->last_pal_pic);
600
601 if (ctx->pic.data[0])
602 avctx->release_buffer(avctx, &ctx->pic);
603
604 ctx->pic.reference = 3;
605 ctx->pic.buffer_hints = FF_BUFFER_HINTS_VALID |
606 FF_BUFFER_HINTS_READABLE |
607 FF_BUFFER_HINTS_PRESERVE |
608 FF_BUFFER_HINTS_REUSABLE;
609
610 if ((ret = ff_get_buffer(avctx, &ctx->pic)) < 0) {
611 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
612 return ret;
613 }
614
615 if (ctx->last_pic.data[0]) {
616 av_assert0(ctx->pic.linesize[0] == ctx->last_pic.linesize[0]);
617 c->last_rgb_pic = ctx->last_pic.data[0] +
618 ctx->last_pic.linesize[0] * (avctx->height - 1);
619 } else {
620 av_log(avctx, AV_LOG_ERROR, "Missing keyframe\n");
621 return AVERROR_INVALIDDATA;
622 }
623 } else {
624 if (ctx->last_pic.data[0])
625 avctx->release_buffer(avctx, &ctx->last_pic);
626
627 ctx->pic.reference = 3;
628 ctx->pic.buffer_hints = FF_BUFFER_HINTS_VALID |
629 FF_BUFFER_HINTS_READABLE |
630 FF_BUFFER_HINTS_PRESERVE |
631 FF_BUFFER_HINTS_REUSABLE;
632
633 if ((ret = avctx->reget_buffer(avctx, &ctx->pic)) < 0) {
634 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
635 return ret;
636 }
637
638 c->last_rgb_pic = NULL;
639 }
640 c->rgb_pic = ctx->pic.data[0] +
641 ctx->pic.linesize[0] * (avctx->height - 1);
642 c->rgb_stride = -ctx->pic.linesize[0];
643
644 ctx->pic.key_frame = keyframe;
645 ctx->pic.pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
646
647 if (is_555) {
648 bytestream2_init(&gB, buf, buf_size);
649
650 if (decode_555(&gB, (uint16_t *)c->rgb_pic, c->rgb_stride >> 1,
651 keyframe, avctx->width, avctx->height))
652 return AVERROR_INVALIDDATA;
653
654 buf_size -= bytestream2_tell(&gB);
655 } else {
656 if (keyframe) {
657 c->corrupted = 0;
658 ff_mss12_slicecontext_reset(&ctx->sc[0]);
659 if (c->slice_split)
660 ff_mss12_slicecontext_reset(&ctx->sc[1]);
661 }
662 if (is_rle) {
663 init_get_bits(&gb, buf, buf_size * 8);
664 if (ret = decode_rle(&gb, c->pal_pic, c->pal_stride,
665 c->rgb_pic, c->rgb_stride, c->pal, keyframe,
666 ctx->split_position, 0,
667 avctx->width, avctx->height))
668 return ret;
669 align_get_bits(&gb);
670
671 if (c->slice_split)
672 if (ret = decode_rle(&gb, c->pal_pic, c->pal_stride,
673 c->rgb_pic, c->rgb_stride, c->pal, keyframe,
674 ctx->split_position, 1,
675 avctx->width, avctx->height))
676 return ret;
677
678 align_get_bits(&gb);
679 buf += get_bits_count(&gb) >> 3;
680 buf_size -= get_bits_count(&gb) >> 3;
681 } else if (!implicit_rect || wmv9_mask != -1) {
682 if (c->corrupted)
683 return AVERROR_INVALIDDATA;
684 bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
685 arith2_init(&acoder, &gB);
686 c->keyframe = keyframe;
687 if (c->corrupted = ff_mss12_decode_rect(&ctx->sc[0], &acoder, 0, 0,
688 avctx->width,
689 ctx->split_position))
690 return AVERROR_INVALIDDATA;
691
692 buf += arith2_get_consumed_bytes(&acoder);
693 buf_size -= arith2_get_consumed_bytes(&acoder);
694 if (c->slice_split) {
695 if (buf_size < 1)
696 return AVERROR_INVALIDDATA;
697 bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
698 arith2_init(&acoder, &gB);
699 if (c->corrupted = ff_mss12_decode_rect(&ctx->sc[1], &acoder, 0,
700 ctx->split_position,
701 avctx->width,
702 avctx->height - ctx->split_position))
703 return AVERROR_INVALIDDATA;
704
705 buf += arith2_get_consumed_bytes(&acoder);
706 buf_size -= arith2_get_consumed_bytes(&acoder);
707 }
708 } else
709 memset(c->pal_pic, 0, c->pal_stride * avctx->height);
710 }
711
712 if (has_wmv9) {
713 for (i = 0; i < used_rects; i++) {
714 int x = wmv9rects[i].x;
715 int y = wmv9rects[i].y;
716 int w = wmv9rects[i].w;
717 int h = wmv9rects[i].h;
718 if (wmv9rects[i].coded) {
719 int WMV9codedFrameSize;
720 if (buf_size < 4 || !(WMV9codedFrameSize = AV_RL24(buf)))
721 return AVERROR_INVALIDDATA;
722 if (ret = decode_wmv9(avctx, buf + 3, buf_size - 3,
723 x, y, w, h, wmv9_mask))
724 return ret;
725 buf += WMV9codedFrameSize + 3;
726 buf_size -= WMV9codedFrameSize + 3;
727 } else {
728 uint8_t *dst = c->rgb_pic + y * c->rgb_stride + x * 3;
729 if (wmv9_mask != -1) {
730 ctx->dsp.mss2_gray_fill_masked(dst, c->rgb_stride,
731 wmv9_mask,
732 c->pal_pic + y * c->pal_stride + x,
733 c->pal_stride,
734 w, h);
735 } else {
736 do {
737 memset(dst, 0x80, w * 3);
738 dst += c->rgb_stride;
739 } while (--h);
740 }
741 }
742 }
743 }
744
745 if (buf_size)
746 av_log(avctx, AV_LOG_WARNING, "buffer not fully consumed\n");
747
748 *got_frame = 1;
749 *(AVFrame *)data = ctx->pic;
750
751 return avpkt->size;
752 }
753
754 static av_cold int wmv9_init(AVCodecContext *avctx)
755 {
756 VC1Context *v = avctx->priv_data;
757 int ret;
758
759 v->s.avctx = avctx;
760 avctx->flags |= CODEC_FLAG_EMU_EDGE;
761 v->s.flags |= CODEC_FLAG_EMU_EDGE;
762
763 if ((ret = ff_vc1_init_common(v)) < 0)
764 return ret;
765 ff_vc1dsp_init(&v->vc1dsp);
766
767 v->profile = PROFILE_MAIN;
768
769 v->zz_8x4 = ff_wmv2_scantableA;
770 v->zz_4x8 = ff_wmv2_scantableB;
771 v->res_y411 = 0;
772 v->res_sprite = 0;
773
774 v->frmrtq_postproc = 7;
775 v->bitrtq_postproc = 31;
776
777 v->res_x8 = 0;
778 v->multires = 0;
779 v->res_fasttx = 1;
780
781 v->fastuvmc = 0;
782
783 v->extended_mv = 0;
784
785 v->dquant = 1;
786 v->vstransform = 1;
787
788 v->res_transtab = 0;
789
790 v->overlap = 0;
791
792 v->s.resync_marker = 0;
793 v->rangered = 0;
794
795 v->s.max_b_frames = avctx->max_b_frames = 0;
796 v->quantizer_mode = 0;
797
798 v->finterpflag = 0;
799
800 v->res_rtm_flag = 1;
801
802 ff_vc1_init_transposed_scantables(v);
803
804 if ((ret = ff_msmpeg4_decode_init(avctx)) < 0 ||
805 (ret = ff_vc1_decode_init_alloc_tables(v)) < 0)
806 return ret;
807
808 /* error concealment */
809 v->s.me.qpel_put = v->s.dsp.put_qpel_pixels_tab;
810 v->s.me.qpel_avg = v->s.dsp.avg_qpel_pixels_tab;
811
812 return 0;
813 }
814
815 static av_cold int mss2_decode_end(AVCodecContext *avctx)
816 {
817 MSS2Context *const ctx = avctx->priv_data;
818
819 if (ctx->pic.data[0])
820 avctx->release_buffer(avctx, &ctx->pic);
821 if (ctx->last_pic.data[0])
822 avctx->release_buffer(avctx, &ctx->last_pic);
823
824 ff_mss12_decode_end(&ctx->c);
825 av_freep(&ctx->c.pal_pic);
826 av_freep(&ctx->c.last_pal_pic);
827 ff_vc1_decode_end(avctx);
828
829 return 0;
830 }
831
832 static av_cold int mss2_decode_init(AVCodecContext *avctx)
833 {
834 MSS2Context * const ctx = avctx->priv_data;
835 MSS12Context *c = &ctx->c;
836 int ret;
837 c->avctx = avctx;
838 avctx->coded_frame = &ctx->pic;
839 if (ret = ff_mss12_decode_init(c, 1, &ctx->sc[0], &ctx->sc[1]))
840 return ret;
841 c->pal_stride = c->mask_stride;
842 c->pal_pic = av_mallocz(c->pal_stride * avctx->height);
843 c->last_pal_pic = av_mallocz(c->pal_stride * avctx->height);
844 if (!c->pal_pic || !c->last_pal_pic) {
845 mss2_decode_end(avctx);
846 return AVERROR(ENOMEM);
847 }
848 if (ret = wmv9_init(avctx)) {
849 mss2_decode_end(avctx);
850 return ret;
851 }
852 ff_mss2dsp_init(&ctx->dsp);
853
854 avctx->pix_fmt = c->free_colours == 127 ? AV_PIX_FMT_RGB555
855 : AV_PIX_FMT_RGB24;
856
857 return 0;
858 }
859
860 AVCodec ff_mss2_decoder = {
861 .name = "mss2",
862 .type = AVMEDIA_TYPE_VIDEO,
863 .id = AV_CODEC_ID_MSS2,
864 .priv_data_size = sizeof(MSS2Context),
865 .init = mss2_decode_init,
866 .close = mss2_decode_end,
867 .decode = mss2_decode_frame,
868 .capabilities = CODEC_CAP_DR1,
869 .long_name = NULL_IF_CONFIG_SMALL("MS Windows Media Video V9 Screen"),
870 };