GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/vmdvideo.c Lines: 149 245 60.8 %
Date: 2021-04-18 21:26:34 Branches: 87 172 50.6 %

Line Branch Exec Source
1
/*
2
 * Sierra VMD video decoder
3
 * Copyright (c) 2004 The FFmpeg Project
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
 * Sierra VMD video decoder
25
 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
26
 * for more information on the Sierra VMD format, visit:
27
 *   http://www.pcisys.net/~melanson/codecs/
28
 *
29
 * The video decoder outputs PAL8 colorspace data. The decoder expects
30
 * a 0x330-byte VMD file header to be transmitted via extradata during
31
 * codec initialization. Each encoded frame that is sent to this decoder
32
 * is expected to be prepended with the appropriate 16-byte frame
33
 * information record from the VMD file.
34
 */
35
36
#include <string.h>
37
38
#include "libavutil/common.h"
39
#include "libavutil/intreadwrite.h"
40
41
#include "avcodec.h"
42
#include "internal.h"
43
#include "bytestream.h"
44
45
#define VMD_HEADER_SIZE 0x330
46
#define PALETTE_COUNT 256
47
48
typedef struct VmdVideoContext {
49
50
    AVCodecContext *avctx;
51
    AVFrame *prev_frame;
52
53
    const unsigned char *buf;
54
    int size;
55
56
    unsigned char palette[PALETTE_COUNT * 4];
57
    unsigned char *unpack_buffer;
58
    int unpack_buffer_size;
59
60
    int x_off, y_off;
61
} VmdVideoContext;
62
63
#define QUEUE_SIZE 0x1000
64
#define QUEUE_MASK 0x0FFF
65
66
128
static int lz_unpack(const unsigned char *src, int src_len,
67
                      unsigned char *dest, int dest_len)
68
{
69
    unsigned char *d;
70
    unsigned char *d_end;
71
    unsigned char queue[QUEUE_SIZE];
72
    unsigned int qpos;
73
    unsigned int dataleft;
74
    unsigned int chainofs;
75
    unsigned int chainlen;
76
    unsigned int speclen;
77
    unsigned char tag;
78
    unsigned int i, j;
79
    GetByteContext gb;
80
81
128
    bytestream2_init(&gb, src, src_len);
82
128
    d = dest;
83
128
    d_end = d + dest_len;
84
128
    dataleft = bytestream2_get_le32(&gb);
85
128
    memset(queue, 0x20, QUEUE_SIZE);
86
128
    if (bytestream2_get_bytes_left(&gb) < 4)
87
        return AVERROR_INVALIDDATA;
88
128
    if (bytestream2_peek_le32(&gb) == 0x56781234) {
89
84
        bytestream2_skipu(&gb, 4);
90
84
        qpos = 0x111;
91
84
        speclen = 0xF + 3;
92
    } else {
93
44
        qpos = 0xFEE;
94
44
        speclen = 100;  /* no speclen */
95
    }
96
97

20091
    while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) {
98
19963
        tag = bytestream2_get_byteu(&gb);
99

19963
        if ((tag == 0xFF) && (dataleft > 8)) {
100

1814
            if (d_end - d < 8 || bytestream2_get_bytes_left(&gb) < 8)
101
                return AVERROR_INVALIDDATA;
102
16326
            for (i = 0; i < 8; i++) {
103
14512
                queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
104
14512
                qpos &= QUEUE_MASK;
105
            }
106
1814
            dataleft -= 8;
107
        } else {
108
162858
            for (i = 0; i < 8; i++) {
109
144819
                if (dataleft == 0)
110
110
                    break;
111
144709
                if (tag & 0x01) {
112

84919
                    if (d_end - d < 1 || bytestream2_get_bytes_left(&gb) < 1)
113
                        return AVERROR_INVALIDDATA;
114
84919
                    queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
115
84919
                    qpos &= QUEUE_MASK;
116
84919
                    dataleft--;
117
                } else {
118
59790
                    chainofs = bytestream2_get_byte(&gb);
119
59790
                    chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4);
120
59790
                    chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3;
121
59790
                    if (chainlen == speclen) {
122
7696
                        chainlen = bytestream2_get_byte(&gb) + 0xF + 3;
123
                    }
124
59790
                    if (d_end - d < chainlen)
125
                        return AVERROR_INVALIDDATA;
126
739328
                    for (j = 0; j < chainlen; j++) {
127
679538
                        *d = queue[chainofs++ & QUEUE_MASK];
128
679538
                        queue[qpos++] = *d++;
129
679538
                        qpos &= QUEUE_MASK;
130
                    }
131
59790
                    dataleft -= chainlen;
132
                }
133
144709
                tag >>= 1;
134
            }
135
        }
136
    }
137
128
    return d - dest;
138
}
139
static int rle_unpack(const unsigned char *src, unsigned char *dest,
140
                      int src_count, int src_size, int dest_len)
141
{
142
    unsigned char *pd;
143
    int i, l, used = 0;
144
    unsigned char *dest_end = dest + dest_len;
145
    GetByteContext gb;
146
    uint16_t run_val;
147
148
    bytestream2_init(&gb, src, src_size);
149
    pd = dest;
150
    if (src_count & 1) {
151
        if (bytestream2_get_bytes_left(&gb) < 1)
152
            return 0;
153
        *pd++ = bytestream2_get_byteu(&gb);
154
        used++;
155
    }
156
157
    do {
158
        if (bytestream2_get_bytes_left(&gb) < 1)
159
            break;
160
        l = bytestream2_get_byteu(&gb);
161
        if (l & 0x80) {
162
            l = (l & 0x7F) * 2;
163
            if (dest_end - pd < l || bytestream2_get_bytes_left(&gb) < l)
164
                return bytestream2_tell(&gb);
165
            bytestream2_get_bufferu(&gb, pd, l);
166
            pd += l;
167
        } else {
168
            if (dest_end - pd < 2*l || bytestream2_get_bytes_left(&gb) < 2)
169
                return bytestream2_tell(&gb);
170
            run_val = bytestream2_get_ne16(&gb);
171
            for (i = 0; i < l; i++) {
172
                AV_WN16(pd, run_val);
173
                pd += 2;
174
            }
175
            l *= 2;
176
        }
177
        used += l;
178
    } while (used < src_count);
179
180
    return bytestream2_tell(&gb);
181
}
182
183
137
static int vmd_decode(VmdVideoContext *s, AVFrame *frame)
184
{
185
    int i;
186
    unsigned int *palette32;
187
    unsigned char r, g, b;
188
189
    GetByteContext gb;
190
191
    unsigned char meth;
192
    unsigned char *dp;   /* pointer to current frame */
193
    unsigned char *pp;   /* pointer to previous frame */
194
    unsigned char len;
195
    int ofs;
196
197
    int frame_x, frame_y, prev_linesize;
198
    int frame_width, frame_height;
199
200
137
    frame_x = AV_RL16(&s->buf[6]);
201
137
    frame_y = AV_RL16(&s->buf[8]);
202
137
    frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
203
137
    frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
204
205

137
    if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
206
6
        (frame_x || frame_y)) {
207
208
        s->x_off = frame_x;
209
        s->y_off = frame_y;
210
    }
211
137
    frame_x -= s->x_off;
212
137
    frame_y -= s->y_off;
213
214

137
    if (frame_x < 0 || frame_width < 0 ||
215
137
        frame_x >= s->avctx->width ||
216
137
        frame_width > s->avctx->width ||
217
137
        frame_x + frame_width > s->avctx->width) {
218
        av_log(s->avctx, AV_LOG_ERROR,
219
               "Invalid horizontal range %d-%d\n",
220
               frame_x, frame_width);
221
        return AVERROR_INVALIDDATA;
222
    }
223

137
    if (frame_y < 0 || frame_height < 0 ||
224
137
        frame_y >= s->avctx->height ||
225
137
        frame_height > s->avctx->height ||
226
137
        frame_y + frame_height > s->avctx->height) {
227
        av_log(s->avctx, AV_LOG_ERROR,
228
               "Invalid vertical range %d-%d\n",
229
               frame_y, frame_height);
230
        return AVERROR_INVALIDDATA;
231
    }
232
233
    /* if only a certain region will be updated, copy the entire previous
234
     * frame before the decode */
235

137
    if (s->prev_frame->data[0] &&
236

8
        (frame_x || frame_y || (frame_width != s->avctx->width) ||
237
5
        (frame_height != s->avctx->height))) {
238
239
131
        memcpy(frame->data[0], s->prev_frame->data[0],
240
131
            s->avctx->height * frame->linesize[0]);
241
    }
242
243
    /* check if there is a new palette */
244
137
    bytestream2_init(&gb, s->buf + 16, s->size - 16);
245
137
    if (s->buf[15] & 0x02) {
246
        bytestream2_skip(&gb, 2);
247
        palette32 = (unsigned int *)s->palette;
248
        if (bytestream2_get_bytes_left(&gb) >= PALETTE_COUNT * 3) {
249
            for (i = 0; i < PALETTE_COUNT; i++) {
250
                r = bytestream2_get_byteu(&gb) * 4;
251
                g = bytestream2_get_byteu(&gb) * 4;
252
                b = bytestream2_get_byteu(&gb) * 4;
253
                palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
254
                palette32[i] |= palette32[i] >> 6 & 0x30303;
255
            }
256
        } else {
257
            av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
258
            return AVERROR_INVALIDDATA;
259
        }
260
    }
261
262
137
    if (!s->size)
263
        return 0;
264
265
    /* originally UnpackFrame in VAG's code */
266
137
    if (bytestream2_get_bytes_left(&gb) < 1)
267
        return AVERROR_INVALIDDATA;
268
137
    meth = bytestream2_get_byteu(&gb);
269
137
    if (meth & 0x80) {
270
        int size;
271
128
        if (!s->unpack_buffer_size) {
272
            av_log(s->avctx, AV_LOG_ERROR,
273
                   "Trying to unpack LZ-compressed frame with no LZ buffer\n");
274
            return AVERROR_INVALIDDATA;
275
        }
276
128
        size = lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb),
277
                         s->unpack_buffer, s->unpack_buffer_size);
278
128
        if (size < 0)
279
            return size;
280
128
        meth &= 0x7F;
281
128
        bytestream2_init(&gb, s->unpack_buffer, size);
282
    }
283
284
137
    dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x];
285
137
    if (s->prev_frame->data[0]) {
286
135
        prev_linesize = s->prev_frame->linesize[0];
287
135
        pp = s->prev_frame->data[0] + frame_y * prev_linesize + frame_x;
288
    } else {
289
2
        pp = NULL;
290
2
        prev_linesize = 0;
291
    }
292

137
    switch (meth) {
293
131
    case 1:
294
11919
        for (i = 0; i < frame_height; i++) {
295
11788
            ofs = 0;
296
            do {
297
56026
                len = bytestream2_get_byte(&gb);
298
56026
                if (len & 0x80) {
299
21508
                    len = (len & 0x7F) + 1;
300
21508
                    if (ofs + len > frame_width ||
301
21508
                        bytestream2_get_bytes_left(&gb) < len)
302
                        return AVERROR_INVALIDDATA;
303
21508
                    bytestream2_get_bufferu(&gb, &dp[ofs], len);
304
21508
                    ofs += len;
305
                } else {
306
                    /* interframe pixel copy */
307

34518
                    if (ofs + len + 1 > frame_width || !pp)
308
                        return AVERROR_INVALIDDATA;
309
34518
                    memcpy(&dp[ofs], &pp[ofs], len + 1);
310
34518
                    ofs += len + 1;
311
                }
312
56026
            } while (ofs < frame_width);
313
11788
            if (ofs > frame_width) {
314
                av_log(s->avctx, AV_LOG_ERROR,
315
                       "offset > width (%d > %d)\n",
316
                       ofs, frame_width);
317
                return AVERROR_INVALIDDATA;
318
            }
319
11788
            dp += frame->linesize[0];
320
11788
            pp  = FF_PTR_ADD(pp, prev_linesize);
321
        }
322
131
        break;
323
324
6
    case 2:
325
771
        for (i = 0; i < frame_height; i++) {
326
765
            bytestream2_get_buffer(&gb, dp, frame_width);
327
765
            dp += frame->linesize[0];
328
        }
329
6
        break;
330
331
    case 3:
332
        for (i = 0; i < frame_height; i++) {
333
            ofs = 0;
334
            do {
335
                len = bytestream2_get_byte(&gb);
336
                if (len & 0x80) {
337
                    len = (len & 0x7F) + 1;
338
                    if (bytestream2_peek_byte(&gb) == 0xFF) {
339
                        int slen = len;
340
                        bytestream2_get_byte(&gb);
341
                        len = rle_unpack(gb.buffer, &dp[ofs],
342
                                         len, bytestream2_get_bytes_left(&gb),
343
                                         frame_width - ofs);
344
                        ofs += slen;
345
                        bytestream2_skip(&gb, len);
346
                    } else {
347
                        if (ofs + len > frame_width ||
348
                            bytestream2_get_bytes_left(&gb) < len)
349
                            return AVERROR_INVALIDDATA;
350
                        bytestream2_get_buffer(&gb, &dp[ofs], len);
351
                        ofs += len;
352
                    }
353
                } else {
354
                    /* interframe pixel copy */
355
                    if (ofs + len + 1 > frame_width || !pp)
356
                        return AVERROR_INVALIDDATA;
357
                    memcpy(&dp[ofs], &pp[ofs], len + 1);
358
                    ofs += len + 1;
359
                }
360
            } while (ofs < frame_width);
361
            if (ofs > frame_width) {
362
                av_log(s->avctx, AV_LOG_ERROR,
363
                       "offset > width (%d > %d)\n",
364
                       ofs, frame_width);
365
                return AVERROR_INVALIDDATA;
366
            }
367
            dp += frame->linesize[0];
368
            pp  = FF_PTR_ADD(pp, prev_linesize);
369
        }
370
        break;
371
    }
372
137
    return 0;
373
}
374
375
5
static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
376
{
377
5
    VmdVideoContext *s = avctx->priv_data;
378
379
5
    av_frame_free(&s->prev_frame);
380
5
    av_freep(&s->unpack_buffer);
381
5
    s->unpack_buffer_size = 0;
382
383
5
    return 0;
384
}
385
386
5
static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
387
{
388
5
    VmdVideoContext *s = avctx->priv_data;
389
    int i;
390
    unsigned int *palette32;
391
5
    int palette_index = 0;
392
    unsigned char r, g, b;
393
    unsigned char *vmd_header;
394
    unsigned char *raw_palette;
395
396
5
    s->avctx = avctx;
397
5
    avctx->pix_fmt = AV_PIX_FMT_PAL8;
398
399
    /* make sure the VMD header made it */
400
5
    if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
401
        av_log(s->avctx, AV_LOG_ERROR, "expected extradata size of %d\n",
402
            VMD_HEADER_SIZE);
403
        return AVERROR_INVALIDDATA;
404
    }
405
5
    vmd_header = (unsigned char *)avctx->extradata;
406
407
5
    s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
408
5
    if (s->unpack_buffer_size) {
409
5
        s->unpack_buffer = av_malloc(s->unpack_buffer_size);
410
5
        if (!s->unpack_buffer)
411
            return AVERROR(ENOMEM);
412
    }
413
414
    /* load up the initial palette */
415
5
    raw_palette = &vmd_header[28];
416
5
    palette32 = (unsigned int *)s->palette;
417
1285
    for (i = 0; i < PALETTE_COUNT; i++) {
418
1280
        r = raw_palette[palette_index++] * 4;
419
1280
        g = raw_palette[palette_index++] * 4;
420
1280
        b = raw_palette[palette_index++] * 4;
421
1280
        palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
422
1280
        palette32[i] |= palette32[i] >> 6 & 0x30303;
423
    }
424
425
5
    s->prev_frame = av_frame_alloc();
426
5
    if (!s->prev_frame) {
427
        vmdvideo_decode_end(avctx);
428
        return AVERROR(ENOMEM);
429
    }
430
431
5
    return 0;
432
}
433
434
137
static int vmdvideo_decode_frame(AVCodecContext *avctx,
435
                                 void *data, int *got_frame,
436
                                 AVPacket *avpkt)
437
{
438
137
    const uint8_t *buf = avpkt->data;
439
137
    int buf_size = avpkt->size;
440
137
    VmdVideoContext *s = avctx->priv_data;
441
137
    AVFrame *frame = data;
442
    int ret;
443
444
137
    s->buf = buf;
445
137
    s->size = buf_size;
446
447
137
    if (buf_size < 16)
448
        return AVERROR_INVALIDDATA;
449
450
137
    if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
451
        return ret;
452
453
137
    if ((ret = vmd_decode(s, frame)) < 0)
454
        return ret;
455
456
    /* make the palette available on the way out */
457
137
    memcpy(frame->data[1], s->palette, PALETTE_COUNT * 4);
458
459
    /* shuffle frames */
460
137
    av_frame_unref(s->prev_frame);
461
137
    if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
462
        return ret;
463
464
137
    *got_frame      = 1;
465
466
    /* report that the buffer was completely consumed */
467
137
    return buf_size;
468
}
469
470
AVCodec ff_vmdvideo_decoder = {
471
    .name           = "vmdvideo",
472
    .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
473
    .type           = AVMEDIA_TYPE_VIDEO,
474
    .id             = AV_CODEC_ID_VMDVIDEO,
475
    .priv_data_size = sizeof(VmdVideoContext),
476
    .init           = vmdvideo_decode_init,
477
    .close          = vmdvideo_decode_end,
478
    .decode         = vmdvideo_decode_frame,
479
    .capabilities   = AV_CODEC_CAP_DR1,
480
};