summaryrefslogtreecommitdiffstats
path: root/libavcodec/vmdvideo.c
blob: 2e91c06374890faf57737b0df8dd4b64c93a9c5a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
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
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
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
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
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
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
/*
 * Sierra VMD video decoder
 *
 * This file is part of Libav.
 *
 * Libav is free software; you can redistribute it and/or
 * 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.
 *
 * Libav is distributed in the hope that it will be useful,
 * 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
 * License along with Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * Sierra VMD video decoder
 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
 * for more information on the Sierra VMD format, visit:
 *   http://www.pcisys.net/~melanson/codecs/
 *
 * The video decoder outputs PAL8 colorspace data. The decoder expects
 * a 0x330-byte VMD file header to be transmitted via extradata during
 * codec initialization. Each encoded frame that is sent to this decoder
 * is expected to be prepended with the appropriate 16-byte frame
 * information record from the VMD file.
 */

#include <string.h>

#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"

#include "avcodec.h"
#include "internal.h"
#include "bytestream.h"

#define VMD_HEADER_SIZE 0x330
#define PALETTE_COUNT 256

typedef struct VmdVideoContext {

    AVCodecContext *avctx;
    AVFrame *prev_frame;

    const unsigned char *buf;
    int size;

    unsigned char palette[PALETTE_COUNT * 4];
    unsigned char *unpack_buffer;
    int unpack_buffer_size;

    int x_off, y_off;
} VmdVideoContext;

#define QUEUE_SIZE 0x1000
#define QUEUE_MASK 0x0FFF

static void lz_unpack(const unsigned char *src, int src_len,
                      unsigned char *dest, int dest_len)
{
    unsigned char *d;
    unsigned char *d_end;
    unsigned char queue[QUEUE_SIZE];
    unsigned int qpos;
    unsigned int dataleft;
    unsigned int chainofs;
    unsigned int chainlen;
    unsigned int speclen;
    unsigned char tag;
    unsigned int i, j;
    GetByteContext gb;

    bytestream2_init(&gb, src, src_len);
    d = dest;
    d_end = d + dest_len;
    dataleft = bytestream2_get_le32(&gb);
    memset(queue, 0x20, QUEUE_SIZE);
    if (bytestream2_get_bytes_left(&gb) < 4)
        return;
    if (bytestream2_peek_le32(&gb) == 0x56781234) {
        bytestream2_get_le32(&gb);
        qpos = 0x111;
        speclen = 0xF + 3;
    } else {
        qpos = 0xFEE;
        speclen = 100;  /* no speclen */
    }

    while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) {
        tag = bytestream2_get_byteu(&gb);
        if ((tag == 0xFF) && (dataleft > 8)) {
            if (d + 8 > d_end || bytestream2_get_bytes_left(&gb) < 8)
                return;
            for (i = 0; i < 8; i++) {
                queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
                qpos &= QUEUE_MASK;
            }
            dataleft -= 8;
        } else {
            for (i = 0; i < 8; i++) {
                if (dataleft == 0)
                    break;
                if (tag & 0x01) {
                    if (d + 1 > d_end || bytestream2_get_bytes_left(&gb) < 1)
                        return;
                    queue[qpos++] = *d++ = bytestream2_get_byte(&gb);
                    qpos &= QUEUE_MASK;
                    dataleft--;
                } else {
                    chainofs = bytestream2_get_byte(&gb);
                    chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4);
                    chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3;
                    if (chainlen == speclen) {
                        chainlen = bytestream2_get_byte(&gb) + 0xF + 3;
                    }
                    if (d + chainlen > d_end)
                        return;
                    for (j = 0; j < chainlen; j++) {
                        *d = queue[chainofs++ & QUEUE_MASK];
                        queue[qpos++] = *d++;
                        qpos &= QUEUE_MASK;
                    }
                    dataleft -= chainlen;
                }
                tag >>= 1;
            }
        }
    }
}

static int rle_unpack(const unsigned char *src, unsigned char *dest,
    int src_count, int src_size, int dest_len)
{
    unsigned char *pd;
    int i, l, used = 0;
    unsigned char *dest_end = dest + dest_len;
    GetByteContext gb;
    uint16_t run_val;

    bytestream2_init(&gb, src, src_size);
    pd = dest;
    if (src_count & 1) {
        if (bytestream2_get_bytes_left(&gb) < 1)
            return 0;
        *pd++ = bytestream2_get_byteu(&gb);
        used++;
    }

    do {
        if (bytestream2_get_bytes_left(&gb) < 1)
            break;
        l = bytestream2_get_byteu(&gb);
        if (l & 0x80) {
            l = (l & 0x7F) * 2;
            if (pd + l > dest_end || bytestream2_get_bytes_left(&gb) < l)
                return bytestream2_tell(&gb);
            bytestream2_get_buffer(&gb, pd, l);
            pd += l;
        } else {
            if (pd + l > dest_end || bytestream2_get_bytes_left(&gb) < 2)
                return bytestream2_tell(&gb);
            run_val = bytestream2_get_ne16(&gb);
            for (i = 0; i < l; i++) {
                AV_WN16(pd, run_val);
                pd += 2;
            }
            l *= 2;
        }
        used += l;
    } while (used < src_count);

    return bytestream2_tell(&gb);
}

static int vmd_decode(VmdVideoContext *s, AVFrame *frame)
{
    int i;
    unsigned int *palette32;
    unsigned char r, g, b;

    GetByteContext gb;

    unsigned char meth;
    unsigned char *dp;   /* pointer to current frame */
    unsigned char *pp;   /* pointer to previous frame */
    unsigned char len;
    int ofs;

    int frame_x, frame_y;
    int frame_width, frame_height;

    frame_x = AV_RL16(&s->buf[6]);
    frame_y = AV_RL16(&s->buf[8]);
    frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
    frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
    if (frame_x < 0 || frame_width < 0 ||
        frame_x >= s->avctx->width ||
        frame_width > s->avctx->width ||
        frame_x + frame_width > s->avctx->width) {
        av_log(s->avctx, AV_LOG_ERROR,
               "Invalid horizontal range %d-%d\n",
               frame_x, frame_width);
        return AVERROR_INVALIDDATA;
    }
    if (frame_y < 0 || frame_height < 0 ||
        frame_y >= s->avctx->height ||
        frame_height > s->avctx->height ||
        frame_y + frame_height > s->avctx->height) {
        av_log(s->avctx, AV_LOG_ERROR,
               "Invalid vertical range %d-%d\n",
               frame_x, frame_width);
        return AVERROR_INVALIDDATA;
    }

    if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
        (frame_x || frame_y)) {

        s->x_off = frame_x;
        s->y_off = frame_y;
    }
    frame_x -= s->x_off;
    frame_y -= s->y_off;

    /* if only a certain region will be updated, copy the entire previous
     * frame before the decode */
    if (s->prev_frame->data[0] &&
        (frame_x || frame_y || (frame_width != s->avctx->width) ||
        (frame_height != s->avctx->height))) {

        memcpy(frame->data[0], s->prev_frame->data[0],
            s->avctx->height * frame->linesize[0]);
    }

    /* check if there is a new palette */
    bytestream2_init(&gb, s->buf + 16, s->size - 16);
    if (s->buf[15] & 0x02) {
        bytestream2_skip(&gb, 2);
        palette32 = (unsigned int *)s->palette;
        if (bytestream2_get_bytes_left(&gb) >= PALETTE_COUNT * 3) {
            for (i = 0; i < PALETTE_COUNT; i++) {
                r = bytestream2_get_byteu(&gb) * 4;
                g = bytestream2_get_byteu(&gb) * 4;
                b = bytestream2_get_byteu(&gb) * 4;
                palette32[i] = (r << 16) | (g << 8) | (b);
            }
        } else {
            av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
            return AVERROR_INVALIDDATA;
        }
        s->size -= PALETTE_COUNT * 3 + 2;
    }

    if (!s->size)
        return 0;

    /* originally UnpackFrame in VAG's code */
    if (bytestream2_get_bytes_left(&gb) < 1)
        return AVERROR_INVALIDDATA;
    meth = bytestream2_get_byteu(&gb);
    if (meth & 0x80) {
        if (!s->unpack_buffer_size) {
            av_log(s->avctx, AV_LOG_ERROR,
                   "Trying to unpack LZ-compressed frame with no LZ buffer\n");
            return AVERROR_INVALIDDATA;
        }
        lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb),
                  s->unpack_buffer, s->unpack_buffer_size);
        meth &= 0x7F;
        bytestream2_init(&gb, s->unpack_buffer, s->unpack_buffer_size);
    }

    dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x];
    pp = &s->prev_frame->data[0][frame_y * s->prev_frame->linesize[0] + frame_x];
    switch (meth) {
    case 1:
        for (i = 0; i < frame_height; i++) {
            ofs = 0;
            do {
                len = bytestream2_get_byte(&gb);
                if (len & 0x80) {
                    len = (len & 0x7F) + 1;
                    if (ofs + len > frame_width ||
                        bytestream2_get_bytes_left(&gb) < len)
                        return AVERROR_INVALIDDATA;
                    bytestream2_get_buffer(&gb, &dp[ofs], len);
                    ofs += len;
                } else {
                    /* interframe pixel copy */
                    if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
                        return AVERROR_INVALIDDATA;
                    memcpy(&dp[ofs], &pp[ofs], len + 1);
                    ofs += len + 1;
                }
            } while (ofs < frame_width);
            if (ofs > frame_width) {
                av_log(s->avctx, AV_LOG_ERROR,
                       "VMD video: offset > width (%d > %d)\n",
                       ofs, frame_width);
                return AVERROR_INVALIDDATA;
            }
            dp += frame->linesize[0];
            pp += s->prev_frame->linesize[0];
        }
        break;

    case 2:
        for (i = 0; i < frame_height; i++) {
            bytestream2_get_buffer(&gb, dp, frame_width);
            dp += frame->linesize[0];
            pp += s->prev_frame->linesize[0];
        }
        break;

    case 3:
        for (i = 0; i < frame_height; i++) {
            ofs = 0;
            do {
                len = bytestream2_get_byte(&gb);
                if (len & 0x80) {
                    len = (len & 0x7F) + 1;
                    if (bytestream2_peek_byte(&gb) == 0xFF) {
                        int slen = len;
                        bytestream2_get_byte(&gb);
                        len = rle_unpack(gb.buffer, &dp[ofs],
                                         len, bytestream2_get_bytes_left(&gb),
                                         frame_width - ofs);
                        ofs += slen;
                        bytestream2_skip(&gb, len);
                    } else {
                        bytestream2_get_buffer(&gb, &dp[ofs], len);
                        ofs += len;
                    }
                } else {
                    /* interframe pixel copy */
                    if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
                        return AVERROR_INVALIDDATA;
                    memcpy(&dp[ofs], &pp[ofs], len + 1);
                    ofs += len + 1;
                }
            } while (ofs < frame_width);
            if (ofs > frame_width) {
                av_log(s->avctx, AV_LOG_ERROR,
                       "VMD video: offset > width (%d > %d)\n",
                       ofs, frame_width);
                return AVERROR_INVALIDDATA;
            }
            dp += frame->linesize[0];
            pp += s->prev_frame->linesize[0];
        }
        break;
    }
    return 0;
}

static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
{
    VmdVideoContext *s = avctx->priv_data;

    av_frame_free(&s->prev_frame);
    av_free(s->unpack_buffer);

    return 0;
}

static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
{
    VmdVideoContext *s = avctx->priv_data;
    int i;
    unsigned int *palette32;
    int palette_index = 0;
    unsigned char r, g, b;
    unsigned char *vmd_header;
    unsigned char *raw_palette;

    s->avctx = avctx;
    avctx->pix_fmt = AV_PIX_FMT_PAL8;

    /* make sure the VMD header made it */
    if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
        av_log(s->avctx, AV_LOG_ERROR, "VMD video: expected extradata size of %d\n",
            VMD_HEADER_SIZE);
        return -1;
    }
    vmd_header = (unsigned char *)avctx->extradata;

    s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
    if (s->unpack_buffer_size) {
        s->unpack_buffer = av_malloc(s->unpack_buffer_size);
        if (!s->unpack_buffer)
            return AVERROR(ENOMEM);
    }

    /* load up the initial palette */
    raw_palette = &vmd_header[28];
    palette32 = (unsigned int *)s->palette;
    for (i = 0; i < PALETTE_COUNT; i++) {
        r = raw_palette[palette_index++] * 4;
        g = raw_palette[palette_index++] * 4;
        b = raw_palette[palette_index++] * 4;
        palette32[i] = (r << 16) | (g << 8) | (b);
    }

    s->prev_frame = av_frame_alloc();
    if (!s->prev_frame) {
        vmdvideo_decode_end(avctx);
        return AVERROR(ENOMEM);
    }

    return 0;
}

static int vmdvideo_decode_frame(AVCodecContext *avctx,
                                 void *data, int *got_frame,
                                 AVPacket *avpkt)
{
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
    VmdVideoContext *s = avctx->priv_data;
    AVFrame *frame = data;
    int ret;

    s->buf = buf;
    s->size = buf_size;

    if (buf_size < 16)
        return AVERROR_INVALIDDATA;

    if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) {
        av_log(s->avctx, AV_LOG_ERROR, "VMD Video: get_buffer() failed\n");
        return ret;
    }

    if ((ret = vmd_decode(s, frame)) < 0)
        return ret;

    /* make the palette available on the way out */
    memcpy(frame->data[1], s->palette, PALETTE_COUNT * 4);

    /* shuffle frames */
    av_frame_unref(s->prev_frame);
    if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
        return ret;

    *got_frame      = 1;

    /* report that the buffer was completely consumed */
    return buf_size;
}

AVCodec ff_vmdvideo_decoder = {
    .name           = "vmdvideo",
    .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_VMDVIDEO,
    .priv_data_size = sizeof(VmdVideoContext),
    .init           = vmdvideo_decode_init,
    .close          = vmdvideo_decode_end,
    .decode         = vmdvideo_decode_frame,
    .capabilities   = AV_CODEC_CAP_DR1,
};
OpenPOWER on IntegriCloud