aboutsummaryrefslogtreecommitdiffstats
path: root/libavcodec/vmnc.c
blob: 23cfe254531c8be4da0ef90e1aa083c836a48b65 (plain) (blame)
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
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
/*
 * VMware Screen Codec (VMnc) decoder
 * Copyright (c) 2006 Konstantin Shishkov
 *
 * 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
 * VMware Screen Codec (VMnc) decoder
 * As Alex Beregszaszi discovered, this is effectively RFB data dump
 */

#include <stdio.h>
#include <stdlib.h>

#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "internal.h"
#include "bytestream.h"

enum EncTypes {
    MAGIC_WMVd = 0x574D5664,
    MAGIC_WMVe,
    MAGIC_WMVf,
    MAGIC_WMVg,
    MAGIC_WMVh,
    MAGIC_WMVi,
    MAGIC_WMVj
};

enum HexTile_Flags {
    HT_RAW =  1, // tile is raw
    HT_BKG =  2, // background color is present
    HT_FG  =  4, // foreground color is present
    HT_SUB =  8, // subrects are present
    HT_CLR = 16  // each subrect has own color
};

/*
 * Decoder context
 */
typedef struct VmncContext {
    AVCodecContext *avctx;
    AVFrame *pic;

    int bpp;
    int bpp2;
    int bigendian;
    uint8_t pal[768];
    int width, height;
    GetByteContext gb;

    /* cursor data */
    int cur_w, cur_h;
    int cur_x, cur_y;
    int cur_hx, cur_hy;
    uint8_t *curbits, *curmask;
    uint8_t *screendta;
} VmncContext;

/* read pixel value from stream */
static av_always_inline int vmnc_get_pixel(GetByteContext *gb, int bpp, int be)
{
    switch (bpp * 2 + be) {
    case 2:
    case 3:
        return bytestream2_get_byte(gb);
    case 4:
        return bytestream2_get_le16(gb);
    case 5:
        return bytestream2_get_be16(gb);
    case 8:
        return bytestream2_get_le32(gb);
    case 9:
        return bytestream2_get_be32(gb);
    default: return 0;
    }
}

static void load_cursor(VmncContext *c)
{
    int i, j, p;
    const int bpp   = c->bpp2;
    uint8_t *dst8   =             c->curbits;
    uint16_t *dst16 = (uint16_t *)c->curbits;
    uint32_t *dst32 = (uint32_t *)c->curbits;

    for (j = 0; j < c->cur_h; j++) {
        for (i = 0; i < c->cur_w; i++) {
            p = vmnc_get_pixel(&c->gb, bpp, c->bigendian);
            if (bpp == 1)
                *dst8++ = p;
            if (bpp == 2)
                *dst16++ = p;
            if (bpp == 4)
                *dst32++ = p;
        }
    }
    dst8  =            c->curmask;
    dst16 = (uint16_t*)c->curmask;
    dst32 = (uint32_t*)c->curmask;
    for (j = 0; j < c->cur_h; j++) {
        for (i = 0; i < c->cur_w; i++) {
            p = vmnc_get_pixel(&c->gb, bpp, c->bigendian);
            if (bpp == 1)
                *dst8++ = p;
            if (bpp == 2)
                *dst16++ = p;
            if (bpp == 4)
                *dst32++ = p;
        }
    }
}

static void put_cursor(uint8_t *dst, int stride, VmncContext *c, int dx, int dy)
{
    int i, j;
    int w, h, x, y;
    w = c->cur_w;
    if (c->width < c->cur_x + c->cur_w)
        w = c->width - c->cur_x;
    h = c->cur_h;
    if (c->height < c->cur_y + c->cur_h)
        h = c->height - c->cur_y;
    x = c->cur_x;
    y = c->cur_y;
    if (x < 0) {
        w += x;
        x  = 0;
    }
    if (y < 0) {
        h += y;
        y  = 0;
    }

    if ((w < 1) || (h < 1))
        return;
    dst += x * c->bpp2 + y * stride;

    if (c->bpp2 == 1) {
        uint8_t *cd = c->curbits, *msk = c->curmask;
        for (j = 0; j < h; j++) {
            for (i = 0; i < w; i++)
                dst[i] = (dst[i] & cd[i]) ^ msk[i];
            msk += c->cur_w;
            cd  += c->cur_w;
            dst += stride;
        }
    } else if (c->bpp2 == 2) {
        uint16_t *cd = (uint16_t*)c->curbits, *msk = (uint16_t*)c->curmask;
        uint16_t *dst2;
        for (j = 0; j < h; j++) {
            dst2 = (uint16_t*)dst;
            for (i = 0; i < w; i++)
                dst2[i] = (dst2[i] & cd[i]) ^ msk[i];
            msk += c->cur_w;
            cd  += c->cur_w;
            dst += stride;
        }
    } else if (c->bpp2 == 4) {
        uint32_t *cd = (uint32_t*)c->curbits, *msk = (uint32_t*)c->curmask;
        uint32_t *dst2;
        for (j = 0; j < h; j++) {
            dst2 = (uint32_t*)dst;
            for (i = 0; i < w; i++)
                dst2[i] = (dst2[i] & cd[i]) ^ msk[i];
            msk += c->cur_w;
            cd  += c->cur_w;
            dst += stride;
        }
    }
}

/* fill rectangle with given color */
static av_always_inline void paint_rect(uint8_t *dst, int dx, int dy,
                                        int w, int h, int color,
                                        int bpp, int stride)
{
    int i, j;
    dst += dx * bpp + dy * stride;
    if (bpp == 1) {
        for (j = 0; j < h; j++) {
            memset(dst, color, w);
            dst += stride;
        }
    } else if (bpp == 2) {
        uint16_t *dst2;
        for (j = 0; j < h; j++) {
            dst2 = (uint16_t*)dst;
            for (i = 0; i < w; i++)
                *dst2++ = color;
            dst += stride;
        }
    } else if (bpp == 4) {
        uint32_t *dst2;
        for (j = 0; j < h; j++) {
            dst2 = (uint32_t*)dst;
            for (i = 0; i < w; i++)
                dst2[i] = color;
            dst += stride;
        }
    }
}

static av_always_inline void paint_raw(uint8_t *dst, int w, int h,
                                       GetByteContext *gb, int bpp,
                                       int be, int stride)
{
    int i, j, p;
    for (j = 0; j < h; j++) {
        for (i = 0; i < w; i++) {
            p = vmnc_get_pixel(gb, bpp, be);
            switch (bpp) {
            case 1:
                dst[i] = p;
                break;
            case 2:
                ((uint16_t*)dst)[i] = p;
                break;
            case 4:
                ((uint32_t*)dst)[i] = p;
                break;
            }
        }
        dst += stride;
    }
}

static int decode_hextile(VmncContext *c, uint8_t* dst, GetByteContext *gb,
                          int w, int h, int stride)
{
    int i, j, k;
    int bg = 0, fg = 0, rects, color, flags, xy, wh;
    const int bpp = c->bpp2;
    uint8_t *dst2;
    int bw = 16, bh = 16;

    for (j = 0; j < h; j += 16) {
        dst2 = dst;
        bw   = 16;
        if (j + 16 > h)
            bh = h - j;
        for (i = 0; i < w; i += 16, dst2 += 16 * bpp) {
            if (bytestream2_get_bytes_left(gb) <= 0) {
                av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
                return AVERROR_INVALIDDATA;
            }
            if (i + 16 > w)
                bw = w - i;
            flags = bytestream2_get_byte(gb);
            if (flags & HT_RAW) {
                if (bytestream2_get_bytes_left(gb) < bw * bh * bpp) {
                    av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
                    return AVERROR_INVALIDDATA;
                }
                paint_raw(dst2, bw, bh, gb, bpp, c->bigendian, stride);
            } else {
                if (flags & HT_BKG)
                    bg = vmnc_get_pixel(gb, bpp, c->bigendian);
                if (flags & HT_FG)
                    fg = vmnc_get_pixel(gb, bpp, c->bigendian);
                rects = 0;
                if (flags & HT_SUB)
                    rects = bytestream2_get_byte(gb);
                color = !!(flags & HT_CLR);

                paint_rect(dst2, 0, 0, bw, bh, bg, bpp, stride);

                if (bytestream2_get_bytes_left(gb) < rects * (color * bpp + 2)) {
                    av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
                    return AVERROR_INVALIDDATA;
                }
                for (k = 0; k < rects; k++) {
                    if (color)
                        fg = vmnc_get_pixel(gb, bpp, c->bigendian);
                    xy = bytestream2_get_byte(gb);
                    wh = bytestream2_get_byte(gb);
                    paint_rect(dst2, xy >> 4, xy & 0xF,
                               (wh>>4)+1, (wh & 0xF)+1, fg, bpp, stride);
                }
            }
        }
        dst += stride * 16;
    }
    return 0;
}

static void reset_buffers(VmncContext *c)
{
    av_freep(&c->curbits);
    av_freep(&c->curmask);
    av_freep(&c->screendta);
    c->cur_w = c->cur_h = 0;
}

static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
                        AVPacket *avpkt)
{
    const uint8_t *buf = avpkt->data;
    int buf_size       = avpkt->size;
    VmncContext * const c = avctx->priv_data;
    GetByteContext *gb = &c->gb;
    uint8_t *outptr;
    int dx, dy, w, h, depth, enc, chunks, res, size_left, ret;

    if ((ret = ff_reget_buffer(avctx, c->pic)) < 0) {
        av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
        return ret;
    }

    bytestream2_init(gb, buf, buf_size);

    c->pic->key_frame = 0;
    c->pic->pict_type = AV_PICTURE_TYPE_P;

    // restore screen after cursor
    if (c->screendta) {
        int i;
        w = c->cur_w;
        if (c->width < c->cur_x + w)
            w = c->width - c->cur_x;
        h = c->cur_h;
        if (c->height < c->cur_y + h)
            h = c->height - c->cur_y;
        dx = c->cur_x;
        if (dx < 0) {
            w += dx;
            dx = 0;
        }
        dy = c->cur_y;
        if (dy < 0) {
            h += dy;
            dy = 0;
        }
        if ((w > 0) && (h > 0)) {
            outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
            for (i = 0; i < h; i++) {
                memcpy(outptr, c->screendta + i * c->cur_w * c->bpp2,
                       w * c->bpp2);
                outptr += c->pic->linesize[0];
            }
        }
    }
    bytestream2_skip(gb, 2);
    chunks = bytestream2_get_be16(gb);
    while (chunks--) {
        dx  = bytestream2_get_be16(gb);
        dy  = bytestream2_get_be16(gb);
        w   = bytestream2_get_be16(gb);
        h   = bytestream2_get_be16(gb);
        enc = bytestream2_get_be32(gb);
        outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
        size_left = bytestream2_get_bytes_left(gb);
        switch (enc) {
        case MAGIC_WMVd: // cursor
            if (size_left < 2 + w * h * c->bpp2 * 2) {
                av_log(avctx, AV_LOG_ERROR,
                       "Premature end of data! (need %i got %i)\n",
                       2 + w * h * c->bpp2 * 2, size_left);
                return AVERROR_INVALIDDATA;
            }
            bytestream2_skip(gb, 2);
            c->cur_w  = w;
            c->cur_h  = h;
            c->cur_hx = dx;
            c->cur_hy = dy;
            if ((c->cur_hx > c->cur_w) || (c->cur_hy > c->cur_h)) {
                av_log(avctx, AV_LOG_ERROR,
                       "Cursor hot spot is not in image: "
                       "%ix%i of %ix%i cursor size\n",
                       c->cur_hx, c->cur_hy, c->cur_w, c->cur_h);
                c->cur_hx = c->cur_hy = 0;
            }
            if (c->cur_w * c->cur_h >= INT_MAX / c->bpp2) {
                reset_buffers(c);
                return AVERROR(EINVAL);
            } else {
                int screen_size = c->cur_w * c->cur_h * c->bpp2;
                if ((ret = av_reallocp(&c->curbits, screen_size)) < 0 ||
                    (ret = av_reallocp(&c->curmask, screen_size)) < 0 ||
                    (ret = av_reallocp(&c->screendta, screen_size)) < 0) {
                    reset_buffers(c);
                    return ret;
                }
            }
            load_cursor(c);
            break;
        case MAGIC_WMVe: // unknown
            bytestream2_skip(gb, 2);
            break;
        case MAGIC_WMVf: // update cursor position
            c->cur_x = dx - c->cur_hx;
            c->cur_y = dy - c->cur_hy;
            break;
        case MAGIC_WMVg: // unknown
            bytestream2_skip(gb, 10);
            break;
        case MAGIC_WMVh: // unknown
            bytestream2_skip(gb, 4);
            break;
        case MAGIC_WMVi: // ServerInitialization struct
            c->pic->key_frame = 1;
            c->pic->pict_type = AV_PICTURE_TYPE_I;
            depth = bytestream2_get_byte(gb);
            if (depth != c->bpp) {
                av_log(avctx, AV_LOG_WARNING, "Depth mismatch. "
                       "Container %i bpp / Codec %i bpp\n", c->bpp, depth);

                if (depth != 8 && depth != 16 && depth != 32) {
                    av_log(avctx, AV_LOG_ERROR,
                           "Unsupported codec bitdepth %i\n", depth);
                    return AVERROR_INVALIDDATA;
                }

                /* reset values */
                c->bpp  = depth;
                c->bpp2 = c->bpp / 8;
            }
            bytestream2_skip(gb, 1);
            c->bigendian = bytestream2_get_byte(gb);
            if (c->bigendian & (~1)) {
                av_log(avctx, AV_LOG_INFO,
                       "Invalid header: bigendian flag = %i\n", c->bigendian);
                return AVERROR_INVALIDDATA;
            }
            //skip the rest of pixel format data
            bytestream2_skip(gb, 13);
            break;
        case MAGIC_WMVj: // unknown
            bytestream2_skip(gb, 2);
            break;
        case 0x00000000: // raw rectangle data
            if ((dx + w > c->width) || (dy + h > c->height)) {
                av_log(avctx, AV_LOG_ERROR,
                       "Incorrect frame size: %ix%i+%ix%i of %ix%i\n",
                       w, h, dx, dy, c->width, c->height);
                return AVERROR_INVALIDDATA;
            }
            if (size_left < w * h * c->bpp2) {
                av_log(avctx, AV_LOG_ERROR,
                       "Premature end of data! (need %i got %i)\n",
                       w * h * c->bpp2, size_left);
                return AVERROR_INVALIDDATA;
            }
            paint_raw(outptr, w, h, gb, c->bpp2, c->bigendian,
                      c->pic->linesize[0]);
            break;
        case 0x00000005: // HexTile encoded rectangle
            if ((dx + w > c->width) || (dy + h > c->height)) {
                av_log(avctx, AV_LOG_ERROR,
                       "Incorrect frame size: %ix%i+%ix%i of %ix%i\n",
                       w, h, dx, dy, c->width, c->height);
                return AVERROR_INVALIDDATA;
            }
            res = decode_hextile(c, outptr, gb, w, h, c->pic->linesize[0]);
            if (res < 0)
                return res;
            break;
        default:
            av_log(avctx, AV_LOG_ERROR, "Unsupported block type 0x%08X\n", enc);
            chunks = 0; // leave chunks decoding loop
        }
    }
    if (c->screendta) {
        int i;
        // save screen data before painting cursor
        w = c->cur_w;
        if (c->width < c->cur_x + w)
            w = c->width - c->cur_x;
        h = c->cur_h;
        if (c->height < c->cur_y + h)
            h = c->height - c->cur_y;
        dx = c->cur_x;
        if (dx < 0) {
            w += dx;
            dx = 0;
        }
        dy = c->cur_y;
        if (dy < 0) {
            h += dy;
            dy = 0;
        }
        if ((w > 0) && (h > 0)) {
            outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
            for (i = 0; i < h; i++) {
                memcpy(c->screendta + i * c->cur_w * c->bpp2, outptr,
                       w * c->bpp2);
                outptr += c->pic->linesize[0];
            }
            outptr = c->pic->data[0];
            put_cursor(outptr, c->pic->linesize[0], c, c->cur_x, c->cur_y);
        }
    }
    *got_frame = 1;
    if ((ret = av_frame_ref(data, c->pic)) < 0)
        return ret;

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

static av_cold int decode_init(AVCodecContext *avctx)
{
    VmncContext * const c = avctx->priv_data;

    c->avctx  = avctx;
    c->width  = avctx->width;
    c->height = avctx->height;
    c->bpp    = avctx->bits_per_coded_sample;
    c->bpp2   = c->bpp / 8;

    switch (c->bpp) {
    case 8:
        avctx->pix_fmt = AV_PIX_FMT_PAL8;
        break;
    case 16:
        avctx->pix_fmt = AV_PIX_FMT_RGB555;
        break;
    case 24:
        /* 24 bits is not technically supported, but some clients might
         * mistakenly set it -- delay the actual check until decode_frame() */
    case 32:
        avctx->pix_fmt = AV_PIX_FMT_RGB32;
        break;
    default:
        av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", c->bpp);
        return AVERROR_INVALIDDATA;
    }

    c->pic = av_frame_alloc();
    if (!c->pic)
        return AVERROR(ENOMEM);

    return 0;
}

static av_cold int decode_end(AVCodecContext *avctx)
{
    VmncContext * const c = avctx->priv_data;

    av_frame_free(&c->pic);

    av_free(c->curbits);
    av_free(c->curmask);
    av_free(c->screendta);
    return 0;
}

AVCodec ff_vmnc_decoder = {
    .name           = "vmnc",
    .long_name      = NULL_IF_CONFIG_SMALL("VMware Screen Codec / VMware Video"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_VMNC,
    .priv_data_size = sizeof(VmncContext),
    .init           = decode_init,
    .close          = decode_end,
    .decode         = decode_frame,
    .capabilities   = CODEC_CAP_DR1,
};