GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/zmbv.c Lines: 249 297 83.8 %
Date: 2020-09-25 14:59:26 Branches: 119 163 73.0 %

Line Branch Exec Source
1
/*
2
 * Zip Motion Blocks Video (ZMBV) decoder
3
 * Copyright (c) 2006 Konstantin Shishkov
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
 * Zip Motion Blocks Video decoder
25
 */
26
27
#include <stdio.h>
28
#include <stdlib.h>
29
30
#include "libavutil/common.h"
31
#include "libavutil/imgutils.h"
32
#include "libavutil/intreadwrite.h"
33
#include "avcodec.h"
34
#include "internal.h"
35
36
#include <zlib.h>
37
38
#define ZMBV_KEYFRAME 1
39
#define ZMBV_DELTAPAL 2
40
41
enum ZmbvFormat {
42
    ZMBV_FMT_NONE  = 0,
43
    ZMBV_FMT_1BPP  = 1,
44
    ZMBV_FMT_2BPP  = 2,
45
    ZMBV_FMT_4BPP  = 3,
46
    ZMBV_FMT_8BPP  = 4,
47
    ZMBV_FMT_15BPP = 5,
48
    ZMBV_FMT_16BPP = 6,
49
    ZMBV_FMT_24BPP = 7,
50
    ZMBV_FMT_32BPP = 8
51
};
52
53
/*
54
 * Decoder context
55
 */
56
typedef struct ZmbvContext {
57
    AVCodecContext *avctx;
58
59
    int bpp;
60
    int alloc_bpp;
61
    unsigned int decomp_size;
62
    uint8_t* decomp_buf;
63
    uint8_t pal[768];
64
    uint8_t *prev, *cur;
65
    int width, height;
66
    int fmt;
67
    int comp;
68
    int flags;
69
    int stride;
70
    int bw, bh, bx, by;
71
    int decomp_len;
72
    int got_keyframe;
73
    z_stream zstream;
74
    int (*decode_xor)(struct ZmbvContext *c);
75
} ZmbvContext;
76
77
/**
78
 * Decode XOR'ed frame - 8bpp version
79
 */
80
81
275
static int zmbv_decode_xor_8(ZmbvContext *c)
82
{
83
275
    uint8_t *src = c->decomp_buf;
84
    uint8_t *output, *prev;
85
    int8_t *mvec;
86
    int x, y;
87
    int d, dx, dy, bw2, bh2;
88
    int block;
89
    int i, j;
90
    int mx, my;
91
92
275
    output = c->cur;
93
275
    prev = c->prev;
94
95
275
    if (c->flags & ZMBV_DELTAPAL) {
96
        for (i = 0; i < 768; i++)
97
            c->pal[i] ^= *src++;
98
    }
99
100
275
    mvec = (int8_t*)src;
101
275
    src += ((c->bx * c->by * 2 + 3) & ~3);
102
103
275
    block = 0;
104
3850
    for (y = 0; y < c->height; y += c->bh) {
105
3575
        bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);
106
75075
        for (x = 0; x < c->width; x += c->bw) {
107
            uint8_t *out, *tprev;
108
109
71500
            d = mvec[block] & 1;
110
71500
            dx = mvec[block] >> 1;
111
71500
            dy = mvec[block + 1] >> 1;
112
71500
            block += 2;
113
114
71500
            bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);
115
116
            /* copy block - motion vectors out of bounds are used to zero blocks */
117
71500
            out = output + x;
118
71500
            tprev = prev + x + dx + dy * c->width;
119
71500
            mx = x + dx;
120
71500
            my = y + dy;
121
1171500
            for (j = 0; j < bh2; j++) {
122

1100000
                if (my + j < 0 || my + j >= c->height) {
123
                    memset(out, 0, bw2);
124

1100000
                } else if (mx >= 0 && mx + bw2 <= c->width){
125
1100000
                    memcpy(out, tprev, sizeof(*out) * bw2);
126
                } else {
127
                    for (i = 0; i < bw2; i++) {
128
                        if (mx + i < 0 || mx + i >= c->width)
129
                            out[i] = 0;
130
                        else
131
                            out[i] = tprev[i];
132
                    }
133
                }
134
1100000
                out += c->width;
135
1100000
                tprev += c->width;
136
            }
137
138
71500
            if (d) { /* apply XOR'ed difference */
139
1486
                out = output + x;
140
25262
                for (j = 0; j < bh2; j++) {
141
404192
                    for (i = 0; i < bw2; i++)
142
380416
                        out[i] ^= *src++;
143
23776
                    out += c->width;
144
                }
145
            }
146
        }
147
3575
        output += c->width * c->bh;
148
3575
        prev += c->width * c->bh;
149
    }
150
275
    if (src - c->decomp_buf != c->decomp_len)
151
1
        av_log(c->avctx, AV_LOG_ERROR, "Used %"PTRDIFF_SPECIFIER" of %i bytes\n",
152
1
               src-c->decomp_buf, c->decomp_len);
153
275
    return 0;
154
}
155
156
/**
157
 * Decode XOR'ed frame - 15bpp and 16bpp version
158
 */
159
160
318
static int zmbv_decode_xor_16(ZmbvContext *c)
161
{
162
318
    uint8_t *src = c->decomp_buf;
163
    uint16_t *output, *prev;
164
    int8_t *mvec;
165
    int x, y;
166
    int d, dx, dy, bw2, bh2;
167
    int block;
168
    int i, j;
169
    int mx, my;
170
171
318
    output = (uint16_t*)c->cur;
172
318
    prev = (uint16_t*)c->prev;
173
174
318
    mvec = (int8_t*)src;
175
318
    src += ((c->bx * c->by * 2 + 3) & ~3);
176
177
318
    block = 0;
178
4452
    for (y = 0; y < c->height; y += c->bh) {
179
4134
        bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);
180
86814
        for (x = 0; x < c->width; x += c->bw) {
181
            uint16_t *out, *tprev;
182
183
82680
            d = mvec[block] & 1;
184
82680
            dx = mvec[block] >> 1;
185
82680
            dy = mvec[block + 1] >> 1;
186
82680
            block += 2;
187
188
82680
            bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);
189
190
            /* copy block - motion vectors out of bounds are used to zero blocks */
191
82680
            out = output + x;
192
82680
            tprev = prev + x + dx + dy * c->width;
193
82680
            mx = x + dx;
194
82680
            my = y + dy;
195
1354680
            for (j = 0; j < bh2; j++) {
196

1272000
                if (my + j < 0 || my + j >= c->height) {
197
335
                    memset(out, 0, bw2 * 2);
198

1271665
                } else if (mx >= 0 && mx + bw2 <= c->width){
199
1271577
                    memcpy(out, tprev, sizeof(*out) * bw2);
200
                } else {
201
1496
                    for (i = 0; i < bw2; i++) {
202

1408
                        if (mx + i < 0 || mx + i >= c->width)
203
304
                            out[i] = 0;
204
                        else
205
1104
                            out[i] = tprev[i];
206
                    }
207
                }
208
1272000
                out += c->width;
209
1272000
                tprev += c->width;
210
            }
211
212
82680
            if (d) { /* apply XOR'ed difference */
213
7776
                out = output + x;
214
128576
                for (j = 0; j < bh2; j++){
215
2053600
                    for (i = 0; i < bw2; i++) {
216
1932800
                        out[i] ^= *((uint16_t*)src);
217
1932800
                        src += 2;
218
                    }
219
120800
                    out += c->width;
220
                }
221
            }
222
        }
223
4134
        output += c->width * c->bh;
224
4134
        prev += c->width * c->bh;
225
    }
226
318
    if (src - c->decomp_buf != c->decomp_len)
227
        av_log(c->avctx, AV_LOG_ERROR, "Used %"PTRDIFF_SPECIFIER" of %i bytes\n",
228
               src-c->decomp_buf, c->decomp_len);
229
318
    return 0;
230
}
231
232
#ifdef ZMBV_ENABLE_24BPP
233
/**
234
 * Decode XOR'ed frame - 24bpp version
235
 */
236
237
static int zmbv_decode_xor_24(ZmbvContext *c)
238
{
239
    uint8_t *src = c->decomp_buf;
240
    uint8_t *output, *prev;
241
    int8_t *mvec;
242
    int x, y;
243
    int d, dx, dy, bw2, bh2;
244
    int block;
245
    int i, j;
246
    int mx, my;
247
    int stride;
248
249
    output = c->cur;
250
    prev = c->prev;
251
252
    stride = c->width * 3;
253
    mvec = (int8_t*)src;
254
    src += ((c->bx * c->by * 2 + 3) & ~3);
255
256
    block = 0;
257
    for (y = 0; y < c->height; y += c->bh) {
258
        bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);
259
        for (x = 0; x < c->width; x += c->bw) {
260
            uint8_t *out, *tprev;
261
262
            d = mvec[block] & 1;
263
            dx = mvec[block] >> 1;
264
            dy = mvec[block + 1] >> 1;
265
            block += 2;
266
267
            bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);
268
269
            /* copy block - motion vectors out of bounds are used to zero blocks */
270
            out = output + x * 3;
271
            tprev = prev + (x + dx) * 3 + dy * stride;
272
            mx = x + dx;
273
            my = y + dy;
274
            for (j = 0; j < bh2; j++) {
275
                if (my + j < 0 || my + j >= c->height) {
276
                    memset(out, 0, bw2 * 3);
277
                } else if (mx >= 0 && mx + bw2 <= c->width){
278
                    memcpy(out, tprev, 3 * bw2);
279
                } else {
280
                    for (i = 0; i < bw2; i++){
281
                        if (mx + i < 0 || mx + i >= c->width) {
282
                            out[i * 3 + 0] = 0;
283
                            out[i * 3 + 1] = 0;
284
                            out[i * 3 + 2] = 0;
285
                        } else {
286
                            out[i * 3 + 0] = tprev[i * 3 + 0];
287
                            out[i * 3 + 1] = tprev[i * 3 + 1];
288
                            out[i * 3 + 2] = tprev[i * 3 + 2];
289
                        }
290
                    }
291
                }
292
                out += stride;
293
                tprev += stride;
294
            }
295
296
            if (d) { /* apply XOR'ed difference */
297
                out = output + x * 3;
298
                for (j = 0; j < bh2; j++) {
299
                    for (i = 0; i < bw2; i++) {
300
                        out[i * 3 + 0] ^= *src++;
301
                        out[i * 3 + 1] ^= *src++;
302
                        out[i * 3 + 2] ^= *src++;
303
                    }
304
                    out += stride;
305
                }
306
            }
307
        }
308
        output += stride * c->bh;
309
        prev += stride * c->bh;
310
    }
311
    if (src - c->decomp_buf != c->decomp_len)
312
        av_log(c->avctx, AV_LOG_ERROR, "Used %"PTRDIFF_SPECIFIER" of %i bytes\n",
313
               src-c->decomp_buf, c->decomp_len);
314
    return 0;
315
}
316
#endif //ZMBV_ENABLE_24BPP
317
318
/**
319
 * Decode XOR'ed frame - 32bpp version
320
 */
321
322
159
static int zmbv_decode_xor_32(ZmbvContext *c)
323
{
324
159
    uint8_t *src = c->decomp_buf;
325
    uint32_t *output, *prev;
326
    int8_t *mvec;
327
    int x, y;
328
    int d, dx, dy, bw2, bh2;
329
    int block;
330
    int i, j;
331
    int mx, my;
332
333
159
    output = (uint32_t*)c->cur;
334
159
    prev = (uint32_t*)c->prev;
335
336
159
    mvec = (int8_t*)src;
337
159
    src += ((c->bx * c->by * 2 + 3) & ~3);
338
339
159
    block = 0;
340
2226
    for (y = 0; y < c->height; y += c->bh) {
341
2067
        bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);
342
43407
        for (x = 0; x < c->width; x += c->bw) {
343
            uint32_t *out, *tprev;
344
345
41340
            d = mvec[block] & 1;
346
41340
            dx = mvec[block] >> 1;
347
41340
            dy = mvec[block + 1] >> 1;
348
41340
            block += 2;
349
350
41340
            bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);
351
352
            /* copy block - motion vectors out of bounds are used to zero blocks */
353
41340
            out = output + x;
354
41340
            tprev = prev + x + dx + dy * c->width;
355
41340
            mx = x + dx;
356
41340
            my = y + dy;
357
677340
            for (j = 0; j < bh2; j++) {
358

636000
                if (my + j < 0 || my + j >= c->height) {
359
176
                    memset(out, 0, bw2 * 4);
360

635824
                } else if (mx >= 0 && mx + bw2 <= c->width){
361
635760
                    memcpy(out, tprev, sizeof(*out) * bw2);
362
                } else {
363
1088
                    for (i = 0; i < bw2; i++){
364

1024
                        if (mx + i < 0 || mx + i >= c->width)
365
256
                            out[i] = 0;
366
                        else
367
768
                            out[i] = tprev[i];
368
                    }
369
                }
370
636000
                out += c->width;
371
636000
                tprev += c->width;
372
            }
373
374
41340
            if (d) { /* apply XOR'ed difference */
375
4451
                out = output + x;
376
73587
                for (j = 0; j < bh2; j++){
377
1175312
                    for (i = 0; i < bw2; i++) {
378
1106176
                        out[i] ^= *((uint32_t *) src);
379
1106176
                        src += 4;
380
                    }
381
69136
                    out += c->width;
382
                }
383
            }
384
        }
385
2067
        output += c->width * c->bh;
386
2067
        prev   += c->width * c->bh;
387
    }
388
159
    if (src - c->decomp_buf != c->decomp_len)
389
        av_log(c->avctx, AV_LOG_ERROR, "Used %"PTRDIFF_SPECIFIER" of %i bytes\n",
390
               src-c->decomp_buf, c->decomp_len);
391
159
    return 0;
392
}
393
394
/**
395
 * Decode intraframe
396
 */
397
8
static int zmbv_decode_intra(ZmbvContext *c)
398
{
399
8
    uint8_t *src = c->decomp_buf;
400
401
    /* make the palette available on the way out */
402
8
    if (c->fmt == ZMBV_FMT_8BPP) {
403
2
        memcpy(c->pal, src, 768);
404
2
        src += 768;
405
    }
406
407
8
    memcpy(c->cur, src, c->width * c->height * (c->bpp / 8));
408
8
    return 0;
409
}
410
411
760
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
412
{
413
760
    AVFrame *frame = data;
414
760
    const uint8_t *buf = avpkt->data;
415
760
    int buf_size = avpkt->size;
416
760
    ZmbvContext * const c = avctx->priv_data;
417
760
    int zret = Z_OK; // Zlib return code
418
760
    int len = buf_size;
419
    int hi_ver, lo_ver, ret;
420
    int expected_size;
421
422
    /* parse header */
423
760
    if (len < 1)
424
        return AVERROR_INVALIDDATA;
425
760
    c->flags = buf[0];
426
760
    buf++; len--;
427
760
    if (c->flags & ZMBV_KEYFRAME) {
428
8
        c->got_keyframe = 0;
429
430
8
        if (len < 6)
431
            return AVERROR_INVALIDDATA;
432
8
        hi_ver = buf[0];
433
8
        lo_ver = buf[1];
434
8
        c->comp = buf[2];
435
8
        c->fmt = buf[3];
436
8
        c->bw = buf[4];
437
8
        c->bh = buf[5];
438
8
        c->decode_xor = NULL;
439
440
8
        buf += 6;
441
8
        len -= 6;
442
8
        av_log(avctx, AV_LOG_DEBUG,
443
               "Flags=%X ver=%i.%i comp=%i fmt=%i blk=%ix%i\n",
444
               c->flags,hi_ver,lo_ver,c->comp,c->fmt,c->bw,c->bh);
445

8
        if (hi_ver != 0 || lo_ver != 1) {
446
            avpriv_request_sample(avctx, "Version %i.%i", hi_ver, lo_ver);
447
            return AVERROR_PATCHWELCOME;
448
        }
449

8
        if (c->bw == 0 || c->bh == 0) {
450
            avpriv_request_sample(avctx, "Block size %ix%i", c->bw, c->bh);
451
            return AVERROR_PATCHWELCOME;
452
        }
453

8
        if (c->comp != 0 && c->comp != 1) {
454
            avpriv_request_sample(avctx, "Compression type %i", c->comp);
455
            return AVERROR_PATCHWELCOME;
456
        }
457
458

8
        switch (c->fmt) {
459
2
        case ZMBV_FMT_8BPP:
460
2
            c->bpp = 8;
461
2
            c->decode_xor = zmbv_decode_xor_8;
462
2
            avctx->pix_fmt = AV_PIX_FMT_PAL8;
463
2
            c->stride = c->width;
464
2
            break;
465
4
        case ZMBV_FMT_15BPP:
466
        case ZMBV_FMT_16BPP:
467
4
            c->bpp = 16;
468
4
            c->decode_xor = zmbv_decode_xor_16;
469
4
            if (c->fmt == ZMBV_FMT_15BPP)
470
2
                avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
471
            else
472
2
                avctx->pix_fmt = AV_PIX_FMT_RGB565LE;
473
4
            c->stride = c->width * 2;
474
4
            break;
475
#ifdef ZMBV_ENABLE_24BPP
476
        case ZMBV_FMT_24BPP:
477
            c->bpp = 24;
478
            c->decode_xor = zmbv_decode_xor_24;
479
            avctx->pix_fmt = AV_PIX_FMT_BGR24;
480
            c->stride = c->width * 3;
481
            break;
482
#endif //ZMBV_ENABLE_24BPP
483
2
        case ZMBV_FMT_32BPP:
484
2
            c->bpp = 32;
485
2
            c->decode_xor = zmbv_decode_xor_32;
486
2
            avctx->pix_fmt = AV_PIX_FMT_BGR0;
487
2
            c->stride = c->width * 4;
488
2
            break;
489
        default:
490
            c->decode_xor = NULL;
491
            avpriv_request_sample(avctx, "Format %i", c->fmt);
492
            return AVERROR_PATCHWELCOME;
493
        }
494
495
8
        zret = inflateReset(&c->zstream);
496
8
        if (zret != Z_OK) {
497
            av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
498
            return AVERROR_UNKNOWN;
499
        }
500
501
8
        if (c->alloc_bpp < c->bpp) {
502
8
            c->cur  = av_realloc_f(c->cur, avctx->width * avctx->height,  (c->bpp / 8));
503
8
            c->prev = av_realloc_f(c->prev, avctx->width * avctx->height,  (c->bpp / 8));
504
8
            c->alloc_bpp = c->bpp;
505
        }
506
8
        c->bx = (c->width + c->bw - 1) / c->bw;
507
8
        c->by = (c->height+ c->bh - 1) / c->bh;
508

8
        if (!c->cur || !c->prev) {
509
            c->alloc_bpp = 0;
510
            return AVERROR(ENOMEM);
511
        }
512
8
        memset(c->cur, 0, avctx->width * avctx->height * (c->bpp / 8));
513
8
        memset(c->prev, 0, avctx->width * avctx->height * (c->bpp / 8));
514
8
        c->got_keyframe = 1;
515
    }
516
760
    if (c->flags & ZMBV_KEYFRAME) {
517
8
        expected_size = avctx->width * avctx->height * (c->bpp / 8);
518
    } else {
519
752
        expected_size = (c->bx * c->by * 2 + 3) & ~3;
520
    }
521
760
    if (avctx->pix_fmt == AV_PIX_FMT_PAL8 &&
522
277
        (c->flags & (ZMBV_DELTAPAL | ZMBV_KEYFRAME)))
523
2
        expected_size += 768;
524
525
760
    if (!c->got_keyframe) {
526
        av_log(avctx, AV_LOG_ERROR, "Error! Got no format or no keyframe!\n");
527
        return AVERROR_INVALIDDATA;
528
    }
529
530
760
    if (c->comp == 0) { // uncompressed data
531
        if (c->decomp_size < len) {
532
            av_log(avctx, AV_LOG_ERROR, "Buffer too small\n");
533
            return AVERROR_INVALIDDATA;
534
        }
535
        memcpy(c->decomp_buf, buf, len);
536
        c->decomp_len = len;
537
    } else { // ZLIB-compressed data
538
760
        c->zstream.total_in = c->zstream.total_out = 0;
539
760
        c->zstream.next_in = buf;
540
760
        c->zstream.avail_in = len;
541
760
        c->zstream.next_out = c->decomp_buf;
542
760
        c->zstream.avail_out = c->decomp_size;
543
760
        zret = inflate(&c->zstream, Z_SYNC_FLUSH);
544

760
        if (zret != Z_OK && zret != Z_STREAM_END) {
545
            av_log(avctx, AV_LOG_ERROR, "inflate error %d\n", zret);
546
            return AVERROR_INVALIDDATA;
547
        }
548
760
        c->decomp_len = c->zstream.total_out;
549
    }
550
760
    if (expected_size > c->decomp_len ||
551

760
        (c->flags & ZMBV_KEYFRAME) && expected_size < c->decomp_len) {
552
        av_log(avctx, AV_LOG_ERROR, "decompressed size %d is incorrect, expected %d\n", c->decomp_len, expected_size);
553
        return AVERROR_INVALIDDATA;
554
    }
555
760
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
556
        return ret;
557
558
760
    if (c->flags & ZMBV_KEYFRAME) {
559
8
        frame->key_frame = 1;
560
8
        frame->pict_type = AV_PICTURE_TYPE_I;
561
8
        zmbv_decode_intra(c);
562
    } else {
563
752
        frame->key_frame = 0;
564
752
        frame->pict_type = AV_PICTURE_TYPE_P;
565
752
        if (c->decomp_len < 2LL * ((c->width + c->bw - 1) / c->bw) * ((c->height + c->bh - 1) / c->bh))
566
            return AVERROR_INVALIDDATA;
567
752
        if (c->decomp_len)
568
752
            c->decode_xor(c);
569
    }
570
571
    /* update frames */
572
    {
573
        uint8_t *out, *src;
574
        int j;
575
576
760
        out = frame->data[0];
577
760
        src = c->cur;
578
760
        switch (c->fmt) {
579
277
        case ZMBV_FMT_8BPP:
580
71189
            for (j = 0; j < 256; j++)
581
70912
                AV_WN32(&frame->data[1][j * 4], 0xFFU << 24 | AV_RB24(&c->pal[j * 3]));
582
        case ZMBV_FMT_15BPP:
583
        case ZMBV_FMT_16BPP:
584
#ifdef ZMBV_ENABLE_24BPP
585
        case ZMBV_FMT_24BPP:
586
#endif
587
        case ZMBV_FMT_32BPP:
588
760
            av_image_copy_plane(out, frame->linesize[0], src, c->stride,
589
                                c->stride, c->height);
590
760
            break;
591
        default:
592
            av_log(avctx, AV_LOG_ERROR, "Cannot handle format %i\n", c->fmt);
593
        }
594
760
        FFSWAP(uint8_t *, c->cur, c->prev);
595
    }
596
760
    *got_frame = 1;
597
598
    /* always report that the buffer was completely consumed */
599
760
    return buf_size;
600
}
601
602
8
static av_cold int decode_init(AVCodecContext *avctx)
603
{
604
8
    ZmbvContext * const c = avctx->priv_data;
605
    int zret; // Zlib return code
606
607
8
    c->avctx = avctx;
608
609
8
    c->width = avctx->width;
610
8
    c->height = avctx->height;
611
612
8
    c->bpp = avctx->bits_per_coded_sample;
613
614
    // Needed if zlib unused or init aborted before inflateInit
615
8
    memset(&c->zstream, 0, sizeof(z_stream));
616
617
8
    if ((avctx->width + 255ULL) * (avctx->height + 64ULL) > FFMIN(avctx->max_pixels, INT_MAX / 4) ) {
618
        av_log(avctx, AV_LOG_ERROR, "Internal buffer (decomp_size) larger than max_pixels or too large\n");
619
        return AVERROR_INVALIDDATA;
620
    }
621
622
8
    c->decomp_size = (avctx->width + 255) * 4 * (avctx->height + 64);
623
624
    /* Allocate decompression buffer */
625
8
    c->decomp_buf = av_mallocz(c->decomp_size);
626
8
    if (!c->decomp_buf) {
627
        av_log(avctx, AV_LOG_ERROR,
628
                "Can't allocate decompression buffer.\n");
629
        return AVERROR(ENOMEM);
630
    }
631
632
8
    c->zstream.zalloc = Z_NULL;
633
8
    c->zstream.zfree = Z_NULL;
634
8
    c->zstream.opaque = Z_NULL;
635
8
    zret = inflateInit(&c->zstream);
636
8
    if (zret != Z_OK) {
637
        av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
638
        return AVERROR_UNKNOWN;
639
    }
640
641
8
    return 0;
642
}
643
644
8
static av_cold int decode_end(AVCodecContext *avctx)
645
{
646
8
    ZmbvContext * const c = avctx->priv_data;
647
648
8
    av_freep(&c->decomp_buf);
649
650
8
    inflateEnd(&c->zstream);
651
8
    av_freep(&c->cur);
652
8
    av_freep(&c->prev);
653
654
8
    return 0;
655
}
656
657
AVCodec ff_zmbv_decoder = {
658
    .name           = "zmbv",
659
    .long_name      = NULL_IF_CONFIG_SMALL("Zip Motion Blocks Video"),
660
    .type           = AVMEDIA_TYPE_VIDEO,
661
    .id             = AV_CODEC_ID_ZMBV,
662
    .priv_data_size = sizeof(ZmbvContext),
663
    .init           = decode_init,
664
    .close          = decode_end,
665
    .decode         = decode_frame,
666
    .capabilities   = AV_CODEC_CAP_DR1,
667
    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
668
};