2 * Copyright (c) 2012 Konstantin Shishkov
4 * This file is part of FFmpeg.
6 * FFmpeg 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.
11 * FFmpeg 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.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * Common functions for Microsoft Screen 1 and 2
28 #include "libavutil/intfloat.h"
29 #include "libavutil/intreadwrite.h"
39 static const int sec_order_sizes[4] = { 1, 7, 6, 1 };
41 enum ContextDirection {
48 static int model_calc_threshold(Model *m)
52 thr = 2 * m->weights[m->num_syms] - 1;
53 thr = ((thr >> 1) + 4 * m->cum_prob[0]) / thr;
55 return FFMIN(thr, 0x3FFF);
58 static void model_reset(Model *m)
62 for (i = 0; i <= m->num_syms; i++) {
64 m->cum_prob[i] = m->num_syms - i;
67 for (i = 0; i < m->num_syms; i++)
68 m->idx2sym[i + 1] = i;
71 static av_cold void model_init(Model *m, int num_syms, int thr_weight)
73 m->num_syms = num_syms;
74 m->thr_weight = thr_weight;
75 m->threshold = num_syms * thr_weight;
78 static void model_rescale_weights(Model *m)
83 if (m->thr_weight == THRESH_ADAPTIVE)
84 m->threshold = model_calc_threshold(m);
85 while (m->cum_prob[0] > m->threshold) {
87 for (i = m->num_syms; i >= 0; i--) {
88 m->cum_prob[i] = cum_prob;
89 m->weights[i] = (m->weights[i] + 1) >> 1;
90 cum_prob += m->weights[i];
95 void ff_mss12_model_update(Model *m, int val)
99 if (m->weights[val] == m->weights[val - 1]) {
100 for (i = val; m->weights[i - 1] == m->weights[val]; i--);
104 sym1 = m->idx2sym[val];
105 sym2 = m->idx2sym[i];
107 m->idx2sym[val] = sym2;
108 m->idx2sym[i] = sym1;
114 for (i = val - 1; i >= 0; i--)
116 model_rescale_weights(m);
119 static void pixctx_reset(PixContext *ctx)
123 if (!ctx->special_initial_cache)
124 for (i = 0; i < ctx->cache_size; i++)
132 model_reset(&ctx->cache_model);
133 model_reset(&ctx->full_model);
135 for (i = 0; i < 15; i++)
136 for (j = 0; j < 4; j++)
137 model_reset(&ctx->sec_models[i][j]);
140 static av_cold void pixctx_init(PixContext *ctx, int cache_size,
141 int full_model_syms, int special_initial_cache)
145 ctx->cache_size = cache_size + 4;
146 ctx->num_syms = cache_size;
147 ctx->special_initial_cache = special_initial_cache;
149 model_init(&ctx->cache_model, ctx->num_syms + 1, THRESH_LOW);
150 model_init(&ctx->full_model, full_model_syms, THRESH_HIGH);
152 for (i = 0, idx = 0; i < 4; i++)
153 for (j = 0; j < sec_order_sizes[i]; j++, idx++)
154 for (k = 0; k < 4; k++)
155 model_init(&ctx->sec_models[idx][k], 2 + i,
156 i ? THRESH_LOW : THRESH_ADAPTIVE);
159 static av_always_inline int decode_pixel(ArithCoder *acoder, PixContext *pctx,
160 uint8_t *ngb, int num_ngb, int any_ngb)
164 if (acoder->overread > MAX_OVERREAD)
165 return AVERROR_INVALIDDATA;
166 val = acoder->get_model_sym(acoder, &pctx->cache_model);
167 if (val < pctx->num_syms) {
172 for (i = 0; i < pctx->cache_size; i++) {
173 for (j = 0; j < num_ngb; j++)
174 if (pctx->cache[i] == ngb[j])
182 val = FFMIN(i, pctx->cache_size - 1);
184 pix = pctx->cache[val];
186 pix = acoder->get_model_sym(acoder, &pctx->full_model);
187 for (i = 0; i < pctx->cache_size - 1; i++)
188 if (pctx->cache[i] == pix)
193 for (i = val; i > 0; i--)
194 pctx->cache[i] = pctx->cache[i - 1];
195 pctx->cache[0] = pix;
201 static int decode_pixel_in_context(ArithCoder *acoder, PixContext *pctx,
202 uint8_t *src, ptrdiff_t stride, int x, int y,
205 uint8_t neighbours[4];
213 memset(neighbours, src[-1], 4);
215 neighbours[TOP] = src[-stride];
217 neighbours[TOP_LEFT] = neighbours[LEFT] = neighbours[TOP];
219 neighbours[TOP_LEFT] = src[-stride - 1];
220 neighbours[ LEFT] = src[-1];
223 neighbours[TOP_RIGHT] = src[-stride + 1];
225 neighbours[TOP_RIGHT] = neighbours[TOP];
229 if (x >= 2 && src[-2] == neighbours[LEFT])
231 if (y >= 2 && src[-2 * stride] == neighbours[TOP])
235 ref_pix[0] = neighbours[0];
236 for (i = 1; i < 4; i++) {
237 for (j = 0; j < nlen; j++)
238 if (ref_pix[j] == neighbours[i])
241 ref_pix[nlen++] = neighbours[i];
249 if (neighbours[TOP] == neighbours[TOP_LEFT]) {
250 if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT])
252 else if (neighbours[LEFT] == neighbours[TOP_LEFT])
256 } else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT]) {
257 if (neighbours[LEFT] == neighbours[TOP_LEFT])
261 } else if (neighbours[LEFT] == neighbours[TOP_LEFT]) {
268 if (neighbours[TOP] == neighbours[TOP_LEFT])
270 else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT])
272 else if (neighbours[LEFT] == neighbours[TOP_LEFT])
274 else if (neighbours[TOP_RIGHT] == neighbours[TOP])
276 else if (neighbours[TOP] == neighbours[LEFT])
286 pix = acoder->get_model_sym(acoder,
287 &pctx->sec_models[layer][sub]);
291 return decode_pixel(acoder, pctx, ref_pix, nlen, 1);
294 static int decode_region(ArithCoder *acoder, uint8_t *dst, uint8_t *rgb_dst,
295 int x, int y, int width, int height, ptrdiff_t stride,
296 ptrdiff_t rgb_stride, PixContext *pctx,
301 rgb_stride = rgb_dst ? rgb_stride : 0;
302 rgb_dst = rgb_dst ? rgb_dst + x * 3 + y * rgb_stride : NULL;
303 dst += x + y * stride;
305 for (j = 0; j < height; j++) {
306 for (i = 0; i < width; i++) {
308 p = decode_pixel(acoder, pctx, NULL, 0, 0);
310 p = decode_pixel_in_context(acoder, pctx, dst + i, stride,
311 i, j, width - i - 1);
317 AV_WB24(rgb_dst + i * 3, pal[p]);
320 rgb_dst = FF_PTR_ADD(rgb_dst, rgb_stride);
326 static void copy_rectangles(MSS12Context const *c,
327 int x, int y, int width, int height)
332 for (j = y; j < y + height; j++) {
333 memcpy(c->rgb_pic + j * c->rgb_stride + x * 3,
334 c->last_rgb_pic + j * c->rgb_stride + x * 3,
336 memcpy(c->pal_pic + j * c->pal_stride + x,
337 c->last_pal_pic + j * c->pal_stride + x,
342 static int motion_compensation(MSS12Context const *c,
343 int x, int y, int width, int height)
345 if (x + c->mvX < 0 || x + c->mvX + width > c->avctx->width ||
346 y + c->mvY < 0 || y + c->mvY + height > c->avctx->height ||
350 uint8_t *dst = c->pal_pic + x + y * c->pal_stride;
351 uint8_t *rgb_dst = c->rgb_pic + x * 3 + y * c->rgb_stride;
357 if (c->last_rgb_pic) {
358 src = c->last_pal_pic + x + y * c->pal_stride;
359 rgb_src = c->last_rgb_pic + x * 3 + y * c->rgb_stride;
361 src = c->pal_pic + x + y * c->pal_stride;
362 rgb_src = c->rgb_pic + x * 3 + y * c->rgb_stride;
364 for (j = 0; j < height; j++) {
365 memmove(dst, src, width);
366 memmove(rgb_dst, rgb_src, width * 3);
367 dst += c->pal_stride;
368 src += c->pal_stride;
369 rgb_dst += c->rgb_stride;
370 rgb_src += c->rgb_stride;
376 static int decode_region_masked(MSS12Context const *c, ArithCoder *acoder,
377 uint8_t *dst, ptrdiff_t stride, uint8_t *mask,
378 ptrdiff_t mask_stride, int x, int y,
379 int width, int height,
383 uint8_t *rgb_dst = c->rgb_pic + x * 3 + y * c->rgb_stride;
385 dst += x + y * stride;
386 mask += x + y * mask_stride;
388 for (j = 0; j < height; j++) {
389 for (i = 0; i < width; i++) {
390 if (c->avctx->err_recognition & AV_EF_EXPLODE &&
391 ( c->rgb_pic && mask[i] != 0x01 && mask[i] != 0x02 && mask[i] != 0x04 ||
392 !c->rgb_pic && mask[i] != 0x80 && mask[i] != 0xFF))
395 if (mask[i] == 0x02) {
396 copy_rectangles(c, x + i, y + j, 1, 1);
397 } else if (mask[i] == 0x04) {
398 if (motion_compensation(c, x + i, y + j, 1, 1))
400 } else if (mask[i] != 0x80) {
402 p = decode_pixel(acoder, pctx, NULL, 0, 0);
404 p = decode_pixel_in_context(acoder, pctx, dst + i, stride,
405 i, j, width - i - 1);
410 AV_WB24(rgb_dst + i * 3, c->pal[p]);
415 rgb_dst += c->rgb_stride;
421 static av_cold void slicecontext_init(SliceContext *sc,
422 int version, int full_model_syms)
424 model_init(&sc->intra_region, 2, THRESH_ADAPTIVE);
425 model_init(&sc->inter_region, 2, THRESH_ADAPTIVE);
426 model_init(&sc->split_mode, 3, THRESH_HIGH);
427 model_init(&sc->edge_mode, 2, THRESH_HIGH);
428 model_init(&sc->pivot, 3, THRESH_LOW);
430 pixctx_init(&sc->intra_pix_ctx, 8, full_model_syms, 0);
432 pixctx_init(&sc->inter_pix_ctx, version ? 3 : 2,
433 full_model_syms, version ? 1 : 0);
436 void ff_mss12_slicecontext_reset(SliceContext *sc)
438 model_reset(&sc->intra_region);
439 model_reset(&sc->inter_region);
440 model_reset(&sc->split_mode);
441 model_reset(&sc->edge_mode);
442 model_reset(&sc->pivot);
443 pixctx_reset(&sc->intra_pix_ctx);
444 pixctx_reset(&sc->inter_pix_ctx);
447 static int decode_pivot(SliceContext *sc, ArithCoder *acoder, int base)
451 inv = acoder->get_model_sym(acoder, &sc->edge_mode);
452 val = acoder->get_model_sym(acoder, &sc->pivot) + 1;
455 if ((base + 1) / 2 - 2 <= 0)
458 val = acoder->get_number(acoder, (base + 1) / 2 - 2) + 3;
461 if ((unsigned)val >= base)
464 return inv ? base - val : val;
467 static int decode_region_intra(SliceContext *sc, ArithCoder *acoder,
468 int x, int y, int width, int height)
470 MSS12Context const *c = sc->c;
473 mode = acoder->get_model_sym(acoder, &sc->intra_region);
476 int i, j, pix, rgb_pix;
477 ptrdiff_t stride = c->pal_stride;
478 ptrdiff_t rgb_stride = c->rgb_stride;
479 uint8_t *dst = c->pal_pic + x + y * stride;
480 uint8_t *rgb_dst = c->rgb_pic ? c->rgb_pic + x * 3 + y * rgb_stride : NULL;
482 pix = decode_pixel(acoder, &sc->intra_pix_ctx, NULL, 0, 0);
485 rgb_pix = c->pal[pix];
486 for (i = 0; i < height; i++, dst += stride) {
487 memset(dst, pix, width);
489 for (j = 0; j < width * 3; j += 3)
490 AV_WB24(rgb_dst + j, rgb_pix);
491 rgb_dst += rgb_stride;
495 return decode_region(acoder, c->pal_pic, c->rgb_pic,
496 x, y, width, height, c->pal_stride, c->rgb_stride,
497 &sc->intra_pix_ctx, &c->pal[0]);
503 static int decode_region_inter(SliceContext *sc, ArithCoder *acoder,
504 int x, int y, int width, int height)
506 MSS12Context const *c = sc->c;
509 mode = acoder->get_model_sym(acoder, &sc->inter_region);
512 mode = decode_pixel(acoder, &sc->inter_pix_ctx, NULL, 0, 0);
516 if (c->avctx->err_recognition & AV_EF_EXPLODE &&
517 ( c->rgb_pic && mode != 0x01 && mode != 0x02 && mode != 0x04 ||
518 !c->rgb_pic && mode != 0x80 && mode != 0xFF))
522 copy_rectangles(c, x, y, width, height);
523 else if (mode == 0x04)
524 return motion_compensation(c, x, y, width, height);
525 else if (mode != 0x80)
526 return decode_region_intra(sc, acoder, x, y, width, height);
528 if (decode_region(acoder, c->mask, NULL,
529 x, y, width, height, c->mask_stride, 0,
530 &sc->inter_pix_ctx, &c->pal[0]) < 0)
532 return decode_region_masked(c, acoder, c->pal_pic,
533 c->pal_stride, c->mask,
542 int ff_mss12_decode_rect(SliceContext *sc, ArithCoder *acoder,
543 int x, int y, int width, int height)
546 if (acoder->overread > MAX_OVERREAD)
547 return AVERROR_INVALIDDATA;
549 mode = acoder->get_model_sym(acoder, &sc->split_mode);
553 if ((pivot = decode_pivot(sc, acoder, height)) < 1)
555 if (ff_mss12_decode_rect(sc, acoder, x, y, width, pivot))
557 if (ff_mss12_decode_rect(sc, acoder, x, y + pivot, width, height - pivot))
561 if ((pivot = decode_pivot(sc, acoder, width)) < 1)
563 if (ff_mss12_decode_rect(sc, acoder, x, y, pivot, height))
565 if (ff_mss12_decode_rect(sc, acoder, x + pivot, y, width - pivot, height))
570 return decode_region_intra(sc, acoder, x, y, width, height);
572 return decode_region_inter(sc, acoder, x, y, width, height);
580 av_cold int ff_mss12_decode_init(MSS12Context *c, int version,
581 SliceContext* sc1, SliceContext *sc2)
583 AVCodecContext *avctx = c->avctx;
586 if (avctx->extradata_size < 52 + 256 * 3) {
587 av_log(avctx, AV_LOG_ERROR, "Insufficient extradata size %d\n",
588 avctx->extradata_size);
589 return AVERROR_INVALIDDATA;
592 if (AV_RB32(avctx->extradata) < avctx->extradata_size) {
593 av_log(avctx, AV_LOG_ERROR,
594 "Insufficient extradata size: expected %"PRIu32" got %d\n",
595 AV_RB32(avctx->extradata),
596 avctx->extradata_size);
597 return AVERROR_INVALIDDATA;
600 avctx->coded_width = FFMAX(AV_RB32(avctx->extradata + 20), avctx->width);
601 avctx->coded_height = FFMAX(AV_RB32(avctx->extradata + 24), avctx->height);
602 if (avctx->coded_width > 4096 || avctx->coded_height > 4096) {
603 av_log(avctx, AV_LOG_ERROR, "Frame dimensions %dx%d too large",
604 avctx->coded_width, avctx->coded_height);
605 return AVERROR_INVALIDDATA;
607 if (avctx->coded_width < 1 || avctx->coded_height < 1) {
608 av_log(avctx, AV_LOG_ERROR, "Frame dimensions %dx%d too small",
609 avctx->coded_width, avctx->coded_height);
610 return AVERROR_INVALIDDATA;
613 av_log(avctx, AV_LOG_DEBUG, "Encoder version %"PRIu32".%"PRIu32"\n",
614 AV_RB32(avctx->extradata + 4), AV_RB32(avctx->extradata + 8));
615 if (version != AV_RB32(avctx->extradata + 4) > 1) {
616 av_log(avctx, AV_LOG_ERROR,
617 "Header version doesn't match codec tag\n");
621 c->free_colours = AV_RB32(avctx->extradata + 48);
622 if ((unsigned)c->free_colours > 256) {
623 av_log(avctx, AV_LOG_ERROR,
624 "Incorrect number of changeable palette entries: %d\n",
626 return AVERROR_INVALIDDATA;
628 av_log(avctx, AV_LOG_DEBUG, "%d free colour(s)\n", c->free_colours);
630 av_log(avctx, AV_LOG_DEBUG, "Display dimensions %"PRIu32"x%"PRIu32"\n",
631 AV_RB32(avctx->extradata + 12), AV_RB32(avctx->extradata + 16));
632 av_log(avctx, AV_LOG_DEBUG, "Coded dimensions %dx%d\n",
633 avctx->coded_width, avctx->coded_height);
634 av_log(avctx, AV_LOG_DEBUG, "%g frames per second\n",
635 av_int2float(AV_RB32(avctx->extradata + 28)));
636 av_log(avctx, AV_LOG_DEBUG, "Bitrate %"PRIu32" bps\n",
637 AV_RB32(avctx->extradata + 32));
638 av_log(avctx, AV_LOG_DEBUG, "Max. lead time %g ms\n",
639 av_int2float(AV_RB32(avctx->extradata + 36)));
640 av_log(avctx, AV_LOG_DEBUG, "Max. lag time %g ms\n",
641 av_int2float(AV_RB32(avctx->extradata + 40)));
642 av_log(avctx, AV_LOG_DEBUG, "Max. seek time %g ms\n",
643 av_int2float(AV_RB32(avctx->extradata + 44)));
646 if (avctx->extradata_size < 60 + 256 * 3) {
647 av_log(avctx, AV_LOG_ERROR,
648 "Insufficient extradata size %d for v2\n",
649 avctx->extradata_size);
650 return AVERROR_INVALIDDATA;
653 c->slice_split = AV_RB32(avctx->extradata + 52);
654 av_log(avctx, AV_LOG_DEBUG, "Slice split %d\n", c->slice_split);
656 c->full_model_syms = AV_RB32(avctx->extradata + 56);
657 if (c->full_model_syms < 2 || c->full_model_syms > 256) {
658 av_log(avctx, AV_LOG_ERROR,
659 "Incorrect number of used colours %d\n",
661 return AVERROR_INVALIDDATA;
663 av_log(avctx, AV_LOG_DEBUG, "Used colours %d\n",
667 c->full_model_syms = 256;
670 for (i = 0; i < 256; i++)
671 c->pal[i] = 0xFFU << 24 | AV_RB24(avctx->extradata + 52 +
672 (version ? 8 : 0) + i * 3);
674 c->mask_stride = FFALIGN(avctx->width, 16);
675 c->mask = av_malloc_array(c->mask_stride, avctx->height);
677 av_log(avctx, AV_LOG_ERROR, "Cannot allocate mask plane\n");
678 return AVERROR(ENOMEM);
682 slicecontext_init(sc1, version, c->full_model_syms);
683 if (c->slice_split) {
685 slicecontext_init(sc2, version, c->full_model_syms);
692 av_cold int ff_mss12_decode_end(MSS12Context *c)