mss12.c 20.7 KB
Newer Older
1 2 3
/*
 * Copyright (c) 2012 Konstantin Shishkov
 *
4
 * This file is part of FFmpeg.
5
 *
6
 * FFmpeg is free software; you can redistribute it and/or
7 8 9 10
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * 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 13 14 15 16
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * 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 19 20 21 22 23 24 25
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * Common functions for Microsoft Screen 1 and 2
 */

26 27
#include <inttypes.h>

28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51
#include "libavutil/intfloat.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "mss12.h"

enum SplitMode {
    SPLIT_VERT = 0,
    SPLIT_HOR,
    SPLIT_NONE
};

static const int sec_order_sizes[4] = { 1, 7, 6, 1 };

enum ContextDirection {
    TOP_LEFT = 0,
    TOP,
    TOP_RIGHT,
    LEFT
};

static int model_calc_threshold(Model *m)
{
    int thr;

Alberto Delmás's avatar
Alberto Delmás committed
52 53
    thr = 2 * m->weights[m->num_syms] - 1;
    thr = ((thr >> 1) + 4 * m->cum_prob[0]) / thr;
54 55 56 57 58 59 60 61 62 63 64 65

    return FFMIN(thr, 0x3FFF);
}

static void model_reset(Model *m)
{
    int i;

    for (i = 0; i <= m->num_syms; i++) {
        m->weights[i]  = 1;
        m->cum_prob[i] = m->num_syms - i;
    }
66 67
    m->weights[0] = 0;
    for (i = 0; i < m->num_syms; i++)
68 69 70 71 72 73 74
        m->idx2sym[i + 1] = i;
}

static av_cold void model_init(Model *m, int num_syms, int thr_weight)
{
    m->num_syms   = num_syms;
    m->thr_weight = thr_weight;
Alberto Delmás's avatar
Alberto Delmás committed
75
    m->threshold  = num_syms * thr_weight;
76 77 78 79 80 81 82
}

static void model_rescale_weights(Model *m)
{
    int i;
    int cum_prob;

Alberto Delmás's avatar
Alberto Delmás committed
83
    if (m->thr_weight == THRESH_ADAPTIVE)
84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120
        m->threshold = model_calc_threshold(m);
    while (m->cum_prob[0] > m->threshold) {
        cum_prob = 0;
        for (i = m->num_syms; i >= 0; i--) {
            m->cum_prob[i] = cum_prob;
            m->weights[i]  = (m->weights[i] + 1) >> 1;
            cum_prob      += m->weights[i];
        }
    }
}

void ff_mss12_model_update(Model *m, int val)
{
    int i;

    if (m->weights[val] == m->weights[val - 1]) {
        for (i = val; m->weights[i - 1] == m->weights[val]; i--);
        if (i != val) {
            int sym1, sym2;

            sym1 = m->idx2sym[val];
            sym2 = m->idx2sym[i];

            m->idx2sym[val]  = sym2;
            m->idx2sym[i]    = sym1;

            val = i;
        }
    }
    m->weights[val]++;
    for (i = val - 1; i >= 0; i--)
        m->cum_prob[i]++;
    model_rescale_weights(m);
}

static void pixctx_reset(PixContext *ctx)
{
121
    int i, j;
122

Alberto Delmás's avatar
Alberto Delmás committed
123 124 125 126 127 128 129 130
    if (!ctx->special_initial_cache)
        for (i = 0; i < ctx->cache_size; i++)
            ctx->cache[i] = i;
    else {
        ctx->cache[0] = 1;
        ctx->cache[1] = 2;
        ctx->cache[2] = 4;
    }
131 132 133 134

    model_reset(&ctx->cache_model);
    model_reset(&ctx->full_model);

135 136 137
    for (i = 0; i < 15; i++)
        for (j = 0; j < 4; j++)
            model_reset(&ctx->sec_models[i][j]);
138 139
}

Alberto Delmás's avatar
Alberto Delmás committed
140 141
static av_cold void pixctx_init(PixContext *ctx, int cache_size,
                                int full_model_syms, int special_initial_cache)
142
{
143
    int i, j, k, idx;
144

Alberto Delmás's avatar
Alberto Delmás committed
145 146 147
    ctx->cache_size            = cache_size + 4;
    ctx->num_syms              = cache_size;
    ctx->special_initial_cache = special_initial_cache;
148 149

    model_init(&ctx->cache_model, ctx->num_syms + 1, THRESH_LOW);
Alberto Delmás's avatar
Alberto Delmás committed
150
    model_init(&ctx->full_model, full_model_syms, THRESH_HIGH);
151

152 153
    for (i = 0, idx = 0; i < 4; i++)
        for (j = 0; j < sec_order_sizes[i]; j++, idx++)
Alberto Delmás's avatar
Alberto Delmás committed
154
            for (k = 0; k < 4; k++)
155
                model_init(&ctx->sec_models[idx][k], 2 + i,
156 157 158
                           i ? THRESH_LOW : THRESH_ADAPTIVE);
}

159 160
static av_always_inline int decode_pixel(ArithCoder *acoder, PixContext *pctx,
                                         uint8_t *ngb, int num_ngb, int any_ngb)
161 162 163 164 165
{
    int i, val, pix;

    val = acoder->get_model_sym(acoder, &pctx->cache_model);
    if (val < pctx->num_syms) {
166 167 168 169 170 171 172 173 174 175 176 177 178
        if (any_ngb) {
            int idx, j;

            idx = 0;
            for (i = 0; i < pctx->cache_size; i++) {
                for (j = 0; j < num_ngb; j++)
                    if (pctx->cache[i] == ngb[j])
                        break;
                if (j == num_ngb) {
                    if (idx == val)
                        break;
                    idx++;
                }
179
            }
180
            val = FFMIN(i, pctx->cache_size - 1);
181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248
        }
        pix = pctx->cache[val];
    } else {
        pix = acoder->get_model_sym(acoder, &pctx->full_model);
        for (i = 0; i < pctx->cache_size - 1; i++)
            if (pctx->cache[i] == pix)
                break;
        val = i;
    }
    if (val) {
        for (i = val; i > 0; i--)
            pctx->cache[i] = pctx->cache[i - 1];
        pctx->cache[0] = pix;
    }

    return pix;
}

static int decode_pixel_in_context(ArithCoder *acoder, PixContext *pctx,
                                   uint8_t *src, int stride, int x, int y,
                                   int has_right)
{
    uint8_t neighbours[4];
    uint8_t ref_pix[4];
    int nlen;
    int layer = 0, sub;
    int pix;
    int i, j;

    if (!y) {
        memset(neighbours, src[-1], 4);
    } else {
        neighbours[TOP] = src[-stride];
        if (!x) {
            neighbours[TOP_LEFT] = neighbours[LEFT] = neighbours[TOP];
        } else {
            neighbours[TOP_LEFT] = src[-stride - 1];
            neighbours[    LEFT] = src[-1];
        }
        if (has_right)
            neighbours[TOP_RIGHT] = src[-stride + 1];
        else
            neighbours[TOP_RIGHT] = neighbours[TOP];
    }

    sub = 0;
    if (x >= 2 && src[-2] == neighbours[LEFT])
        sub  = 1;
    if (y >= 2 && src[-2 * stride] == neighbours[TOP])
        sub |= 2;

    nlen = 1;
    ref_pix[0] = neighbours[0];
    for (i = 1; i < 4; i++) {
        for (j = 0; j < nlen; j++)
            if (ref_pix[j] == neighbours[i])
                break;
        if (j == nlen)
            ref_pix[nlen++] = neighbours[i];
    }

    switch (nlen) {
    case 1:
        layer = 0;
        break;
    case 2:
        if (neighbours[TOP] == neighbours[TOP_LEFT]) {
            if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT])
249
                layer = 1;
250 251 252
            else if (neighbours[LEFT] == neighbours[TOP_LEFT])
                layer = 2;
            else
253
                layer = 3;
254 255
        } else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT]) {
            if (neighbours[LEFT] == neighbours[TOP_LEFT])
256
                layer = 4;
257 258 259 260 261
            else
                layer = 5;
        } else if (neighbours[LEFT] == neighbours[TOP_LEFT]) {
            layer = 6;
        } else {
262
            layer = 7;
263 264 265 266
        }
        break;
    case 3:
        if (neighbours[TOP] == neighbours[TOP_LEFT])
267
            layer = 8;
268
        else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT])
269
            layer = 9;
270
        else if (neighbours[LEFT] == neighbours[TOP_LEFT])
271
            layer = 10;
272
        else if (neighbours[TOP_RIGHT] == neighbours[TOP])
273
            layer = 11;
274
        else if (neighbours[TOP] == neighbours[LEFT])
275
            layer = 12;
276
        else
277 278 279 280
            layer = 13;
        break;
    case 4:
        layer = 14;
281 282 283
        break;
    }

Alberto Delmás's avatar
Alberto Delmás committed
284
    pix = acoder->get_model_sym(acoder,
285
                                &pctx->sec_models[layer][sub]);
286 287 288
    if (pix < nlen)
        return ref_pix[pix];
    else
289
        return decode_pixel(acoder, pctx, ref_pix, nlen, 1);
290 291
}

Alberto Delmás's avatar
Alberto Delmás committed
292
static int decode_region(ArithCoder *acoder, uint8_t *dst, uint8_t *rgb_pic,
293
                         int x, int y, int width, int height, int stride,
Alberto Delmás's avatar
Alberto Delmás committed
294
                         int rgb_stride, PixContext *pctx, const uint32_t *pal)
295
{
Alberto Delmás's avatar
Alberto Delmás committed
296 297
    int i, j, p;
    uint8_t *rgb_dst = rgb_pic + x * 3 + y * rgb_stride;
298 299 300 301 302 303

    dst += x + y * stride;

    for (j = 0; j < height; j++) {
        for (i = 0; i < width; i++) {
            if (!i && !j)
304
                p = decode_pixel(acoder, pctx, NULL, 0, 0);
Alberto Delmás's avatar
Alberto Delmás committed
305 306 307 308
            else
                p = decode_pixel_in_context(acoder, pctx, dst + i, stride,
                                            i, j, width - i - 1);
            dst[i] = p;
309

Alberto Delmás's avatar
Alberto Delmás committed
310 311
            if (rgb_pic)
                AV_WB24(rgb_dst + i * 3, pal[p]);
312
        }
Alberto Delmás's avatar
Alberto Delmás committed
313 314
        dst     += stride;
        rgb_dst += rgb_stride;
315 316 317 318 319
    }

    return 0;
}

Alberto Delmás's avatar
Alberto Delmás committed
320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370
static void copy_rectangles(MSS12Context const *c,
                            int x, int y, int width, int height)
{
    int j;

    if (c->last_rgb_pic)
        for (j = y; j < y + height; j++) {
            memcpy(c->rgb_pic      + j * c->rgb_stride + x * 3,
                   c->last_rgb_pic + j * c->rgb_stride + x * 3,
                   width * 3);
            memcpy(c->pal_pic      + j * c->pal_stride + x,
                   c->last_pal_pic + j * c->pal_stride + x,
                   width);
        }
}

static int motion_compensation(MSS12Context const *c,
                               int x, int y, int width, int height)
{
    if (x + c->mvX < 0 || x + c->mvX + width  > c->avctx->width  ||
        y + c->mvY < 0 || y + c->mvY + height > c->avctx->height ||
        !c->rgb_pic)
        return -1;
    else {
        uint8_t *dst     = c->pal_pic + x     + y * c->pal_stride;
        uint8_t *rgb_dst = c->rgb_pic + x * 3 + y * c->rgb_stride;
        uint8_t *src;
        uint8_t *rgb_src;
        int j;
        x += c->mvX;
        y += c->mvY;
        if (c->last_rgb_pic) {
            src     = c->last_pal_pic + x +     y * c->pal_stride;
            rgb_src = c->last_rgb_pic + x * 3 + y * c->rgb_stride;
        } else {
            src     = c->pal_pic + x     + y * c->pal_stride;
            rgb_src = c->rgb_pic + x * 3 + y * c->rgb_stride;
        }
        for (j = 0; j < height; j++) {
            memmove(dst, src, width);
            memmove(rgb_dst, rgb_src, width * 3);
            dst     += c->pal_stride;
            src     += c->pal_stride;
            rgb_dst += c->rgb_stride;
            rgb_src += c->rgb_stride;
        }
    }
    return 0;
}

static int decode_region_masked(MSS12Context const *c, ArithCoder *acoder,
371 372 373 374 375
                                uint8_t *dst, int stride, uint8_t *mask,
                                int mask_stride, int x, int y,
                                int width, int height,
                                PixContext *pctx)
{
Alberto Delmás's avatar
Alberto Delmás committed
376 377
    int i, j, p;
    uint8_t *rgb_dst = c->rgb_pic + x * 3 + y * c->rgb_stride;
378 379 380 381 382 383

    dst  += x + y * stride;
    mask += x + y * mask_stride;

    for (j = 0; j < height; j++) {
        for (i = 0; i < width; i++) {
Alberto Delmás's avatar
Alberto Delmás committed
384 385 386 387 388 389 390 391 392 393 394 395
            if (c->avctx->err_recognition & AV_EF_EXPLODE &&
                ( c->rgb_pic && mask[i] != 0x01 && mask[i] != 0x02 && mask[i] != 0x04 ||
                 !c->rgb_pic && mask[i] != 0x80 && mask[i] != 0xFF))
                return -1;

            if (mask[i] == 0x02) {
                copy_rectangles(c, x + i, y + j, 1, 1);
            } else if (mask[i] == 0x04) {
                if (motion_compensation(c, x + i, y + j, 1, 1))
                    return -1;
            } else if (mask[i] != 0x80) {
                if (!i && !j)
396
                    p = decode_pixel(acoder, pctx, NULL, 0, 0);
Alberto Delmás's avatar
Alberto Delmás committed
397 398 399 400 401 402 403
                else
                    p = decode_pixel_in_context(acoder, pctx, dst + i, stride,
                                                i, j, width - i - 1);
                dst[i] = p;
                if (c->rgb_pic)
                    AV_WB24(rgb_dst + i * 3, c->pal[p]);
            }
404
        }
Alberto Delmás's avatar
Alberto Delmás committed
405 406 407
        dst     += stride;
        mask    += mask_stride;
        rgb_dst += c->rgb_stride;
408 409 410 411 412
    }

    return 0;
}

413 414
static av_cold void slicecontext_init(SliceContext *sc,
                                      int version, int full_model_syms)
415
{
416 417 418 419 420 421 422 423 424 425
    model_init(&sc->intra_region, 2, THRESH_ADAPTIVE);
    model_init(&sc->inter_region, 2, THRESH_ADAPTIVE);
    model_init(&sc->split_mode,   3, THRESH_HIGH);
    model_init(&sc->edge_mode,    2, THRESH_HIGH);
    model_init(&sc->pivot,        3, THRESH_LOW);

    pixctx_init(&sc->intra_pix_ctx, 8, full_model_syms, 0);

    pixctx_init(&sc->inter_pix_ctx, version ? 3 : 2,
                full_model_syms, version ? 1 : 0);
426 427
}

428
void ff_mss12_slicecontext_reset(SliceContext *sc)
429
{
430 431 432 433 434 435 436
    model_reset(&sc->intra_region);
    model_reset(&sc->inter_region);
    model_reset(&sc->split_mode);
    model_reset(&sc->edge_mode);
    model_reset(&sc->pivot);
    pixctx_reset(&sc->intra_pix_ctx);
    pixctx_reset(&sc->inter_pix_ctx);
437 438
}

Alberto Delmás's avatar
Alberto Delmás committed
439
static int decode_pivot(SliceContext *sc, ArithCoder *acoder, int base)
440 441 442
{
    int val, inv;

Alberto Delmás's avatar
Alberto Delmás committed
443 444
    inv = acoder->get_model_sym(acoder, &sc->edge_mode);
    val = acoder->get_model_sym(acoder, &sc->pivot) + 1;
445 446

    if (val > 2) {
Alberto Delmás's avatar
Alberto Delmás committed
447 448 449
        if ((base + 1) / 2 - 2 <= 0)
            return -1;

450 451 452
        val = acoder->get_number(acoder, (base + 1) / 2 - 2) + 3;
    }

453
    if ((unsigned)val >= base)
Alberto Delmás's avatar
Alberto Delmás committed
454
        return -1;
455 456 457 458

    return inv ? base - val : val;
}

Alberto Delmás's avatar
Alberto Delmás committed
459
static int decode_region_intra(SliceContext *sc, ArithCoder *acoder,
460 461
                               int x, int y, int width, int height)
{
Alberto Delmás's avatar
Alberto Delmás committed
462
    MSS12Context const *c = sc->c;
463 464
    int mode;

Alberto Delmás's avatar
Alberto Delmás committed
465
    mode = acoder->get_model_sym(acoder, &sc->intra_region);
466 467

    if (!mode) {
Alberto Delmás's avatar
Alberto Delmás committed
468 469 470 471 472 473
        int i, j, pix, rgb_pix;
        int stride       = c->pal_stride;
        int rgb_stride   = c->rgb_stride;
        uint8_t *dst     = c->pal_pic + x     + y * stride;
        uint8_t *rgb_dst = c->rgb_pic + x * 3 + y * rgb_stride;

474
        pix     = decode_pixel(acoder, &sc->intra_pix_ctx, NULL, 0, 0);
Alberto Delmás's avatar
Alberto Delmás committed
475 476
        rgb_pix = c->pal[pix];
        for (i = 0; i < height; i++, dst += stride, rgb_dst += rgb_stride) {
477
            memset(dst, pix, width);
Alberto Delmás's avatar
Alberto Delmás committed
478 479 480 481
            if (c->rgb_pic)
                for (j = 0; j < width * 3; j += 3)
                    AV_WB24(rgb_dst + j, rgb_pix);
        }
482
    } else {
Alberto Delmás's avatar
Alberto Delmás committed
483 484 485
        return decode_region(acoder, c->pal_pic, c->rgb_pic,
                             x, y, width, height, c->pal_stride, c->rgb_stride,
                             &sc->intra_pix_ctx, &c->pal[0]);
486 487 488 489 490
    }

    return 0;
}

Alberto Delmás's avatar
Alberto Delmás committed
491
static int decode_region_inter(SliceContext *sc, ArithCoder *acoder,
492 493
                               int x, int y, int width, int height)
{
Alberto Delmás's avatar
Alberto Delmás committed
494
    MSS12Context const *c = sc->c;
495 496
    int mode;

Alberto Delmás's avatar
Alberto Delmás committed
497
    mode = acoder->get_model_sym(acoder, &sc->inter_region);
498 499

    if (!mode) {
500
        mode = decode_pixel(acoder, &sc->inter_pix_ctx, NULL, 0, 0);
Alberto Delmás's avatar
Alberto Delmás committed
501 502 503 504 505 506 507 508 509 510 511 512

        if (c->avctx->err_recognition & AV_EF_EXPLODE &&
            ( c->rgb_pic && mode != 0x01 && mode != 0x02 && mode != 0x04 ||
             !c->rgb_pic && mode != 0x80 && mode != 0xFF))
            return -1;

        if (mode == 0x02)
            copy_rectangles(c, x, y, width, height);
        else if (mode == 0x04)
            return motion_compensation(c, x, y, width, height);
        else if (mode != 0x80)
            return decode_region_intra(sc, acoder, x, y, width, height);
513
    } else {
Alberto Delmás's avatar
Alberto Delmás committed
514 515 516
        if (decode_region(acoder, c->mask, NULL,
                          x, y, width, height, c->mask_stride, 0,
                          &sc->inter_pix_ctx, &c->pal[0]) < 0)
517
            return -1;
Alberto Delmás's avatar
Alberto Delmás committed
518 519 520
        return decode_region_masked(c, acoder, c->pal_pic,
                                    c->pal_stride, c->mask,
                                    c->mask_stride,
521
                                    x, y, width, height,
Alberto Delmás's avatar
Alberto Delmás committed
522
                                    &sc->intra_pix_ctx);
523 524 525 526 527
    }

    return 0;
}

Alberto Delmás's avatar
Alberto Delmás committed
528
int ff_mss12_decode_rect(SliceContext *sc, ArithCoder *acoder,
529 530 531 532
                         int x, int y, int width, int height)
{
    int mode, pivot;

Alberto Delmás's avatar
Alberto Delmás committed
533
    mode = acoder->get_model_sym(acoder, &sc->split_mode);
534 535 536

    switch (mode) {
    case SPLIT_VERT:
Alberto Delmás's avatar
Alberto Delmás committed
537
        if ((pivot = decode_pivot(sc, acoder, height)) < 1)
538
            return -1;
Alberto Delmás's avatar
Alberto Delmás committed
539
        if (ff_mss12_decode_rect(sc, acoder, x, y, width, pivot))
540
            return -1;
Alberto Delmás's avatar
Alberto Delmás committed
541
        if (ff_mss12_decode_rect(sc, acoder, x, y + pivot, width, height - pivot))
542 543 544
            return -1;
        break;
    case SPLIT_HOR:
Alberto Delmás's avatar
Alberto Delmás committed
545
        if ((pivot = decode_pivot(sc, acoder, width)) < 1)
546
            return -1;
Alberto Delmás's avatar
Alberto Delmás committed
547
        if (ff_mss12_decode_rect(sc, acoder, x, y, pivot, height))
548
            return -1;
Alberto Delmás's avatar
Alberto Delmás committed
549
        if (ff_mss12_decode_rect(sc, acoder, x + pivot, y, width - pivot, height))
550 551 552
            return -1;
        break;
    case SPLIT_NONE:
Alberto Delmás's avatar
Alberto Delmás committed
553 554
        if (sc->c->keyframe)
            return decode_region_intra(sc, acoder, x, y, width, height);
555
        else
Alberto Delmás's avatar
Alberto Delmás committed
556
            return decode_region_inter(sc, acoder, x, y, width, height);
557 558 559 560 561 562 563
    default:
        return -1;
    }

    return 0;
}

564 565
av_cold int ff_mss12_decode_init(MSS12Context *c, int version,
                                 SliceContext* sc1, SliceContext *sc2)
566
{
Alberto Delmás's avatar
Alberto Delmás committed
567
    AVCodecContext *avctx = c->avctx;
568 569 570 571 572 573 574 575 576 577
    int i;

    if (avctx->extradata_size < 52 + 256 * 3) {
        av_log(avctx, AV_LOG_ERROR, "Insufficient extradata size %d\n",
               avctx->extradata_size);
        return AVERROR_INVALIDDATA;
    }

    if (AV_RB32(avctx->extradata) < avctx->extradata_size) {
        av_log(avctx, AV_LOG_ERROR,
578
               "Insufficient extradata size: expected %"PRIu32" got %d\n",
579 580 581 582 583
               AV_RB32(avctx->extradata),
               avctx->extradata_size);
        return AVERROR_INVALIDDATA;
    }

584 585
    avctx->coded_width  = FFMAX(AV_RB32(avctx->extradata + 20), avctx->width);
    avctx->coded_height = FFMAX(AV_RB32(avctx->extradata + 24), avctx->height);
Alberto Delmás's avatar
Alberto Delmás committed
586 587 588 589 590
    if (avctx->coded_width > 4096 || avctx->coded_height > 4096) {
        av_log(avctx, AV_LOG_ERROR, "Frame dimensions %dx%d too large",
               avctx->coded_width, avctx->coded_height);
        return AVERROR_INVALIDDATA;
    }
591 592 593 594 595
    if (avctx->coded_width < 1 || avctx->coded_height < 1) {
        av_log(avctx, AV_LOG_ERROR, "Frame dimensions %dx%d too small",
               avctx->coded_width, avctx->coded_height);
        return AVERROR_INVALIDDATA;
    }
Alberto Delmás's avatar
Alberto Delmás committed
596

597
    av_log(avctx, AV_LOG_DEBUG, "Encoder version %"PRIu32".%"PRIu32"\n",
598
           AV_RB32(avctx->extradata + 4), AV_RB32(avctx->extradata + 8));
Alberto Delmás's avatar
Alberto Delmás committed
599 600 601 602 603 604 605
    if (version != AV_RB32(avctx->extradata + 4) > 1) {
        av_log(avctx, AV_LOG_ERROR,
               "Header version doesn't match codec tag\n");
        return -1;
    }

    c->free_colours = AV_RB32(avctx->extradata + 48);
606 607 608 609 610 611 612 613
    if ((unsigned)c->free_colours > 256) {
        av_log(avctx, AV_LOG_ERROR,
               "Incorrect number of changeable palette entries: %d\n",
               c->free_colours);
        return AVERROR_INVALIDDATA;
    }
    av_log(avctx, AV_LOG_DEBUG, "%d free colour(s)\n", c->free_colours);

614
    av_log(avctx, AV_LOG_DEBUG, "Display dimensions %"PRIu32"x%"PRIu32"\n",
615 616 617 618 619
           AV_RB32(avctx->extradata + 12), AV_RB32(avctx->extradata + 16));
    av_log(avctx, AV_LOG_DEBUG, "Coded dimensions %dx%d\n",
           avctx->coded_width, avctx->coded_height);
    av_log(avctx, AV_LOG_DEBUG, "%g frames per second\n",
           av_int2float(AV_RB32(avctx->extradata + 28)));
620
    av_log(avctx, AV_LOG_DEBUG, "Bitrate %"PRIu32" bps\n",
621 622 623 624 625 626 627 628
           AV_RB32(avctx->extradata + 32));
    av_log(avctx, AV_LOG_DEBUG, "Max. lead time %g ms\n",
           av_int2float(AV_RB32(avctx->extradata + 36)));
    av_log(avctx, AV_LOG_DEBUG, "Max. lag time %g ms\n",
           av_int2float(AV_RB32(avctx->extradata + 40)));
    av_log(avctx, AV_LOG_DEBUG, "Max. seek time %g ms\n",
           av_int2float(AV_RB32(avctx->extradata + 44)));

Alberto Delmás's avatar
Alberto Delmás committed
629 630 631 632 633 634 635
    if (version) {
        if (avctx->extradata_size < 60 + 256 * 3) {
            av_log(avctx, AV_LOG_ERROR,
                   "Insufficient extradata size %d for v2\n",
                   avctx->extradata_size);
            return AVERROR_INVALIDDATA;
        }
636

Alberto Delmás's avatar
Alberto Delmás committed
637 638
        c->slice_split = AV_RB32(avctx->extradata + 52);
        av_log(avctx, AV_LOG_DEBUG, "Slice split %d\n", c->slice_split);
639

Alberto Delmás's avatar
Alberto Delmás committed
640 641 642 643 644 645 646 647 648 649 650 651 652
        c->full_model_syms = AV_RB32(avctx->extradata + 56);
        if (c->full_model_syms < 2 || c->full_model_syms > 256) {
            av_log(avctx, AV_LOG_ERROR,
                   "Incorrect number of used colours %d\n",
                   c->full_model_syms);
            return AVERROR_INVALIDDATA;
        }
        av_log(avctx, AV_LOG_DEBUG, "Used colours %d\n",
               c->full_model_syms);
    } else {
        c->slice_split     = 0;
        c->full_model_syms = 256;
    }
653

Alberto Delmás's avatar
Alberto Delmás committed
654
    for (i = 0; i < 256; i++)
655
        c->pal[i] = 0xFFU << 24 | AV_RB24(avctx->extradata + 52 +
Alberto Delmás's avatar
Alberto Delmás committed
656 657 658
                            (version ? 8 : 0) + i * 3);

    c->mask_stride = FFALIGN(avctx->width, 16);
659
    c->mask        = av_malloc_array(c->mask_stride, avctx->height);
660 661 662 663 664
    if (!c->mask) {
        av_log(avctx, AV_LOG_ERROR, "Cannot allocate mask plane\n");
        return AVERROR(ENOMEM);
    }

665 666 667 668 669 670 671
    sc1->c = c;
    slicecontext_init(sc1, version, c->full_model_syms);
    if (c->slice_split) {
        sc2->c = c;
        slicecontext_init(sc2, version, c->full_model_syms);
    }
    c->corrupted = 1;
672 673 674 675

    return 0;
}

Alberto Delmás's avatar
Alberto Delmás committed
676
av_cold int ff_mss12_decode_end(MSS12Context *c)
677 678 679 680 681
{
    av_freep(&c->mask);

    return 0;
}