libavcodec/vmnc.c

   1 /*
   2  * VMware Screen Codec (VMnc) decoder
   3  * Copyright (c) 2006 Konstantin Shishkov
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; 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  * VMware Screen Codec (VMnc) decoder
  25  * As Alex Beregszaszi discovered, this is effectively RFB data dump
  26  */
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30
  31 #include "libavutil/common.h"
  32 #include "libavutil/intreadwrite.h"
  33 #include "avcodec.h"
  34 #include "internal.h"
  35 #include "bytestream.h"
  36
  37 enum EncTypes {
  38     MAGIC_WMVd = 0x574D5664,
  39     MAGIC_WMVe,
  40     MAGIC_WMVf,
  41     MAGIC_WMVg,
  42     MAGIC_WMVh,
  43     MAGIC_WMVi,
  44     MAGIC_WMVj
  45 };
  46
  47 enum HexTile_Flags {
  48     HT_RAW =  1, // tile is raw
  49     HT_BKG =  2, // background color is present
  50     HT_FG  =  4, // foreground color is present
  51     HT_SUB =  8, // subrects are present
  52     HT_CLR = 16  // each subrect has own color
  53 };
  54
  55 /*
  56  * Decoder context
  57  */
  58 typedef struct VmncContext {
  59     AVCodecContext *avctx;
  60     AVFrame *pic;
  61
  62     int bpp;
  63     int bpp2;
  64     int bigendian;
  65     uint8_t pal[768];
  66     int width, height;
  67     GetByteContext gb;
  68
  69     /* cursor data */
  70     int cur_w, cur_h;
  71     int cur_x, cur_y;
  72     int cur_hx, cur_hy;
  73     uint8_t *curbits, *curmask;
  74     uint8_t *screendta;
  75 } VmncContext;
  76
  77 /* read pixel value from stream */
  78 static av_always_inline int vmnc_get_pixel(GetByteContext *gb, int bpp, int be)
  79 {
  80     switch (bpp * 2 + be) {
  81     case 2:
  82     case 3:
  83         return bytestream2_get_byte(gb);
  84     case 4:
  85         return bytestream2_get_le16(gb);
  86     case 5:
  87         return bytestream2_get_be16(gb);
  88     case 8:
  89         return bytestream2_get_le32(gb);
  90     case 9:
  91         return bytestream2_get_be32(gb);
  92     default: return 0;
  93     }
  94 }
  95
  96 static void load_cursor(VmncContext *c)
  97 {
  98     int i, j, p;
  99     const int bpp   = c->bpp2;
 100     uint8_t *dst8   =             c->curbits;
 101     uint16_t *dst16 = (uint16_t *)c->curbits;
 102     uint32_t *dst32 = (uint32_t *)c->curbits;
 103
 104     for (j = 0; j < c->cur_h; j++) {
 105         for (i = 0; i < c->cur_w; i++) {
 106             p = vmnc_get_pixel(&c->gb, bpp, c->bigendian);
 107             if (bpp == 1)
 108                 *dst8++ = p;
 109             if (bpp == 2)
 110                 *dst16++ = p;
 111             if (bpp == 4)
 112                 *dst32++ = p;
 113         }
 114     }
 115     dst8  =            c->curmask;
 116     dst16 = (uint16_t*)c->curmask;
 117     dst32 = (uint32_t*)c->curmask;
 118     for (j = 0; j < c->cur_h; j++) {
 119         for (i = 0; i < c->cur_w; i++) {
 120             p = vmnc_get_pixel(&c->gb, bpp, c->bigendian);
 121             if (bpp == 1)
 122                 *dst8++ = p;
 123             if (bpp == 2)
 124                 *dst16++ = p;
 125             if (bpp == 4)
 126                 *dst32++ = p;
 127         }
 128     }
 129 }
 130
 131 static void put_cursor(uint8_t *dst, int stride, VmncContext *c, int dx, int dy)
 132 {
 133     int i, j;
 134     int w, h, x, y;
 135     w = c->cur_w;
 136     if (c->width < c->cur_x + c->cur_w)
 137         w = c->width - c->cur_x;
 138     h = c->cur_h;
 139     if (c->height < c->cur_y + c->cur_h)
 140         h = c->height - c->cur_y;
 141     x = c->cur_x;
 142     y = c->cur_y;
 143     if (x < 0) {
 144         w += x;
 145         x  = 0;
 146     }
 147     if (y < 0) {
 148         h += y;
 149         y  = 0;
 150     }
 151
 152     if ((w < 1) || (h < 1))
 153         return;
 154     dst += x * c->bpp2 + y * stride;
 155
 156     if (c->bpp2 == 1) {
 157         uint8_t *cd = c->curbits, *msk = c->curmask;
 158         for (j = 0; j < h; j++) {
 159             for (i = 0; i < w; i++)
 160                 dst[i] = (dst[i] & cd[i]) ^ msk[i];
 161             msk += c->cur_w;
 162             cd  += c->cur_w;
 163             dst += stride;
 164         }
 165     } else if (c->bpp2 == 2) {
 166         uint16_t *cd = (uint16_t*)c->curbits, *msk = (uint16_t*)c->curmask;
 167         uint16_t *dst2;
 168         for (j = 0; j < h; j++) {
 169             dst2 = (uint16_t*)dst;
 170             for (i = 0; i < w; i++)
 171                 dst2[i] = (dst2[i] & cd[i]) ^ msk[i];
 172             msk += c->cur_w;
 173             cd  += c->cur_w;
 174             dst += stride;
 175         }
 176     } else if (c->bpp2 == 4) {
 177         uint32_t *cd = (uint32_t*)c->curbits, *msk = (uint32_t*)c->curmask;
 178         uint32_t *dst2;
 179         for (j = 0; j < h; j++) {
 180             dst2 = (uint32_t*)dst;
 181             for (i = 0; i < w; i++)
 182                 dst2[i] = (dst2[i] & cd[i]) ^ msk[i];
 183             msk += c->cur_w;
 184             cd  += c->cur_w;
 185             dst += stride;
 186         }
 187     }
 188 }
 189
 190 /* fill rectangle with given color */
 191 static av_always_inline void paint_rect(uint8_t *dst, int dx, int dy,
 192                                         int w, int h, int color,
 193                                         int bpp, int stride)
 194 {
 195     int i, j;
 196     dst += dx * bpp + dy * stride;
 197     if (bpp == 1) {
 198         for (j = 0; j < h; j++) {
 199             memset(dst, color, w);
 200             dst += stride;
 201         }
 202     } else if (bpp == 2) {
 203         uint16_t *dst2;
 204         for (j = 0; j < h; j++) {
 205             dst2 = (uint16_t*)dst;
 206             for (i = 0; i < w; i++)
 207                 *dst2++ = color;
 208             dst += stride;
 209         }
 210     } else if (bpp == 4) {
 211         uint32_t *dst2;
 212         for (j = 0; j < h; j++) {
 213             dst2 = (uint32_t*)dst;
 214             for (i = 0; i < w; i++)
 215                 dst2[i] = color;
 216             dst += stride;
 217         }
 218     }
 219 }
 220
 221 static av_always_inline void paint_raw(uint8_t *dst, int w, int h,
 222                                        GetByteContext *gb, int bpp,
 223                                        int be, int stride)
 224 {
 225     int i, j, p;
 226     for (j = 0; j < h; j++) {
 227         for (i = 0; i < w; i++) {
 228             p = vmnc_get_pixel(gb, bpp, be);
 229             switch (bpp) {
 230             case 1:
 231                 dst[i] = p;
 232                 break;
 233             case 2:
 234                 ((uint16_t*)dst)[i] = p;
 235                 break;
 236             case 4:
 237                 ((uint32_t*)dst)[i] = p;
 238                 break;
 239             }
 240         }
 241         dst += stride;
 242     }
 243 }
 244
 245 static int decode_hextile(VmncContext *c, uint8_t* dst, GetByteContext *gb,
 246                           int w, int h, int stride)
 247 {
 248     int i, j, k;
 249     int bg = 0, fg = 0, rects, color, flags, xy, wh;
 250     const int bpp = c->bpp2;
 251     uint8_t *dst2;
 252     int bw = 16, bh = 16;
 253
 254     for (j = 0; j < h; j += 16) {
 255         dst2 = dst;
 256         bw   = 16;
 257         if (j + 16 > h)
 258             bh = h - j;
 259         for (i = 0; i < w; i += 16, dst2 += 16 * bpp) {
 260             if (bytestream2_get_bytes_left(gb) <= 0) {
 261                 av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
 262                 return AVERROR_INVALIDDATA;
 263             }
 264             if (i + 16 > w)
 265                 bw = w - i;
 266             flags = bytestream2_get_byte(gb);
 267             if (flags & HT_RAW) {
 268                 if (bytestream2_get_bytes_left(gb) < bw * bh * bpp) {
 269                     av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
 270                     return AVERROR_INVALIDDATA;
 271                 }
 272                 paint_raw(dst2, bw, bh, gb, bpp, c->bigendian, stride);
 273             } else {
 274                 if (flags & HT_BKG)
 275                     bg = vmnc_get_pixel(gb, bpp, c->bigendian);
 276                 if (flags & HT_FG)
 277                     fg = vmnc_get_pixel(gb, bpp, c->bigendian);
 278                 rects = 0;
 279                 if (flags & HT_SUB)
 280                     rects = bytestream2_get_byte(gb);
 281                 color = !!(flags & HT_CLR);
 282
 283                 paint_rect(dst2, 0, 0, bw, bh, bg, bpp, stride);
 284
 285                 if (bytestream2_get_bytes_left(gb) < rects * (color * bpp + 2)) {
 286                     av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
 287                     return AVERROR_INVALIDDATA;
 288                 }
 289                 for (k = 0; k < rects; k++) {
 290                     int rect_x, rect_y, rect_w, rect_h;
 291                     if (color)
 292                         fg = vmnc_get_pixel(gb, bpp, c->bigendian);
 293                     xy = bytestream2_get_byte(gb);
 294                     wh = bytestream2_get_byte(gb);
 295
 296                     rect_x = xy >> 4;
 297                     rect_y = xy & 0xF;
 298                     rect_w = (wh >> 4) + 1;
 299                     rect_h = (wh & 0xF) + 1;
 300
 301                     if (rect_x + rect_w > bw || rect_y + rect_h > bh) {
 302                         av_log(c->avctx, AV_LOG_ERROR, "Invalid subrect\n");
 303                         return AVERROR_INVALIDDATA;
 304                     }
 305
 306                     paint_rect(dst2, rect_x, rect_y,
 307                                rect_w, rect_h, fg, bpp, stride);
 308                 }
 309             }
 310         }
 311         dst += stride * 16;
 312     }
 313     return 0;
 314 }
 315
 316 static void reset_buffers(VmncContext *c)
 317 {
 318     av_freep(&c->curbits);
 319     av_freep(&c->curmask);
 320     av_freep(&c->screendta);
 321     c->cur_w = c->cur_h = 0;
 322 }
 323
 324 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
 325                         AVPacket *avpkt)
 326 {
 327     const uint8_t *buf = avpkt->data;
 328     int buf_size       = avpkt->size;
 329     VmncContext * const c = avctx->priv_data;
 330     GetByteContext *gb = &c->gb;
 331     uint8_t *outptr;
 332     int dx, dy, w, h, depth, enc, chunks, res, size_left, ret;
 333
 334     if ((ret = ff_reget_buffer(avctx, c->pic)) < 0) {
 335         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 336         return ret;
 337     }
 338
 339     bytestream2_init(gb, buf, buf_size);
 340
 341     c->pic->key_frame = 0;
 342     c->pic->pict_type = AV_PICTURE_TYPE_P;
 343
 344     // restore screen after cursor
 345     if (c->screendta) {
 346         int i;
 347         w = c->cur_w;
 348         if (c->width < c->cur_x + w)
 349             w = c->width - c->cur_x;
 350         h = c->cur_h;
 351         if (c->height < c->cur_y + h)
 352             h = c->height - c->cur_y;
 353         dx = c->cur_x;
 354         if (dx < 0) {
 355             w += dx;
 356             dx = 0;
 357         }
 358         dy = c->cur_y;
 359         if (dy < 0) {
 360             h += dy;
 361             dy = 0;
 362         }
 363         if ((w > 0) && (h > 0)) {
 364             outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
 365             for (i = 0; i < h; i++) {
 366                 memcpy(outptr, c->screendta + i * c->cur_w * c->bpp2,
 367                        w * c->bpp2);
 368                 outptr += c->pic->linesize[0];
 369             }
 370         }
 371     }
 372     bytestream2_skip(gb, 2);
 373     chunks = bytestream2_get_be16(gb);
 374     while (chunks--) {
 375         dx  = bytestream2_get_be16(gb);
 376         dy  = bytestream2_get_be16(gb);
 377         w   = bytestream2_get_be16(gb);
 378         h   = bytestream2_get_be16(gb);
 379         enc = bytestream2_get_be32(gb);
 380         outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
 381         size_left = bytestream2_get_bytes_left(gb);
 382         switch (enc) {
 383         case MAGIC_WMVd: // cursor
 384             if (size_left < 2 + w * h * c->bpp2 * 2) {
 385                 av_log(avctx, AV_LOG_ERROR,
 386                        "Premature end of data! (need %i got %i)\n",
 387                        2 + w * h * c->bpp2 * 2, size_left);
 388                 return AVERROR_INVALIDDATA;
 389             }
 390             bytestream2_skip(gb, 2);
 391             c->cur_w  = w;
 392             c->cur_h  = h;
 393             c->cur_hx = dx;
 394             c->cur_hy = dy;
 395             if ((c->cur_hx > c->cur_w) || (c->cur_hy > c->cur_h)) {
 396                 av_log(avctx, AV_LOG_ERROR,
 397                        "Cursor hot spot is not in image: "
 398                        "%ix%i of %ix%i cursor size\n",
 399                        c->cur_hx, c->cur_hy, c->cur_w, c->cur_h);
 400                 c->cur_hx = c->cur_hy = 0;
 401             }
 402             if (c->cur_w * c->cur_h >= INT_MAX / c->bpp2) {
 403                 reset_buffers(c);
 404                 return AVERROR(EINVAL);
 405             } else {
 406                 int screen_size = c->cur_w * c->cur_h * c->bpp2;
 407                 if ((ret = av_reallocp(&c->curbits, screen_size)) < 0 ||
 408                     (ret = av_reallocp(&c->curmask, screen_size)) < 0 ||
 409                     (ret = av_reallocp(&c->screendta, screen_size)) < 0) {
 410                     reset_buffers(c);
 411                     return ret;
 412                 }
 413             }
 414             load_cursor(c);
 415             break;
 416         case MAGIC_WMVe: // unknown
 417             bytestream2_skip(gb, 2);
 418             break;
 419         case MAGIC_WMVf: // update cursor position
 420             c->cur_x = dx - c->cur_hx;
 421             c->cur_y = dy - c->cur_hy;
 422             break;
 423         case MAGIC_WMVg: // unknown
 424             bytestream2_skip(gb, 10);
 425             break;
 426         case MAGIC_WMVh: // unknown
 427             bytestream2_skip(gb, 4);
 428             break;
 429         case MAGIC_WMVi: // ServerInitialization struct
 430             c->pic->key_frame = 1;
 431             c->pic->pict_type = AV_PICTURE_TYPE_I;
 432             depth = bytestream2_get_byte(gb);
 433             if (depth != c->bpp) {
 434                 av_log(avctx, AV_LOG_WARNING, "Depth mismatch. "
 435                        "Container %i bpp / Codec %i bpp\n", c->bpp, depth);
 436
 437                 if (depth != 8 && depth != 16 && depth != 32) {
 438                     av_log(avctx, AV_LOG_ERROR,
 439                            "Unsupported codec bitdepth %i\n", depth);
 440                     return AVERROR_INVALIDDATA;
 441                 }
 442
 443                 /* reset values */
 444                 c->bpp  = depth;
 445                 c->bpp2 = c->bpp / 8;
 446             }
 447             bytestream2_skip(gb, 1);
 448             c->bigendian = bytestream2_get_byte(gb);
 449             if (c->bigendian & (~1)) {
 450                 av_log(avctx, AV_LOG_INFO,
 451                        "Invalid header: bigendian flag = %i\n", c->bigendian);
 452                 return AVERROR_INVALIDDATA;
 453             }
 454             //skip the rest of pixel format data
 455             bytestream2_skip(gb, 13);
 456             break;
 457         case MAGIC_WMVj: // unknown
 458             bytestream2_skip(gb, 2);
 459             break;
 460         case 0x00000000: // raw rectangle data
 461             if ((dx + w > c->width) || (dy + h > c->height)) {
 462                 av_log(avctx, AV_LOG_ERROR,
 463                        "Incorrect frame size: %ix%i+%ix%i of %ix%i\n",
 464                        w, h, dx, dy, c->width, c->height);
 465                 return AVERROR_INVALIDDATA;
 466             }
 467             if (size_left < w * h * c->bpp2) {
 468                 av_log(avctx, AV_LOG_ERROR,
 469                        "Premature end of data! (need %i got %i)\n",
 470                        w * h * c->bpp2, size_left);
 471                 return AVERROR_INVALIDDATA;
 472             }
 473             paint_raw(outptr, w, h, gb, c->bpp2, c->bigendian,
 474                       c->pic->linesize[0]);
 475             break;
 476         case 0x00000005: // HexTile encoded rectangle
 477             if ((dx + w > c->width) || (dy + h > c->height)) {
 478                 av_log(avctx, AV_LOG_ERROR,
 479                        "Incorrect frame size: %ix%i+%ix%i of %ix%i\n",
 480                        w, h, dx, dy, c->width, c->height);
 481                 return AVERROR_INVALIDDATA;
 482             }
 483             res = decode_hextile(c, outptr, gb, w, h, c->pic->linesize[0]);
 484             if (res < 0)
 485                 return res;
 486             break;
 487         default:
 488             av_log(avctx, AV_LOG_ERROR, "Unsupported block type 0x%08X\n", enc);
 489             chunks = 0; // leave chunks decoding loop
 490         }
 491     }
 492     if (c->screendta) {
 493         int i;
 494         // save screen data before painting cursor
 495         w = c->cur_w;
 496         if (c->width < c->cur_x + w)
 497             w = c->width - c->cur_x;
 498         h = c->cur_h;
 499         if (c->height < c->cur_y + h)
 500             h = c->height - c->cur_y;
 501         dx = c->cur_x;
 502         if (dx < 0) {
 503             w += dx;
 504             dx = 0;
 505         }
 506         dy = c->cur_y;
 507         if (dy < 0) {
 508             h += dy;
 509             dy = 0;
 510         }
 511         if ((w > 0) && (h > 0)) {
 512             outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
 513             for (i = 0; i < h; i++) {
 514                 memcpy(c->screendta + i * c->cur_w * c->bpp2, outptr,
 515                        w * c->bpp2);
 516                 outptr += c->pic->linesize[0];
 517             }
 518             outptr = c->pic->data[0];
 519             put_cursor(outptr, c->pic->linesize[0], c, c->cur_x, c->cur_y);
 520         }
 521     }
 522     *got_frame = 1;
 523     if ((ret = av_frame_ref(data, c->pic)) < 0)
 524         return ret;
 525
 526     /* always report that the buffer was completely consumed */
 527     return buf_size;
 528 }
 529
 530 static av_cold int decode_init(AVCodecContext *avctx)
 531 {
 532     VmncContext * const c = avctx->priv_data;
 533
 534     c->avctx  = avctx;
 535     c->width  = avctx->width;
 536     c->height = avctx->height;
 537     c->bpp    = avctx->bits_per_coded_sample;
 538     c->bpp2   = c->bpp / 8;
 539
 540     switch (c->bpp) {
 541     case 8:
 542         avctx->pix_fmt = AV_PIX_FMT_PAL8;
 543         break;
 544     case 16:
 545         avctx->pix_fmt = AV_PIX_FMT_RGB555;
 546         break;
 547     case 24:
 548         /* 24 bits is not technically supported, but some clients might
 549          * mistakenly set it -- delay the actual check until decode_frame() */
 550     case 32:
 551         avctx->pix_fmt = AV_PIX_FMT_RGB32;
 552         break;
 553     default:
 554         av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", c->bpp);
 555         return AVERROR_INVALIDDATA;
 556     }
 557
 558     c->pic = av_frame_alloc();
 559     if (!c->pic)
 560         return AVERROR(ENOMEM);
 561
 562     return 0;
 563 }
 564
 565 static av_cold int decode_end(AVCodecContext *avctx)
 566 {
 567     VmncContext * const c = avctx->priv_data;
 568
 569     av_frame_free(&c->pic);
 570
 571     av_free(c->curbits);
 572     av_free(c->curmask);
 573     av_free(c->screendta);
 574     return 0;
 575 }
 576
 577 AVCodec ff_vmnc_decoder = {
 578     .name           = "vmnc",
 579     .long_name      = NULL_IF_CONFIG_SMALL("VMware Screen Codec / VMware Video"),
 580     .type           = AVMEDIA_TYPE_VIDEO,
 581     .id             = AV_CODEC_ID_VMNC,
 582     .priv_data_size = sizeof(VmncContext),
 583     .init           = decode_init,
 584     .close          = decode_end,
 585     .decode         = decode_frame,
 586     .capabilities   = AV_CODEC_CAP_DR1,
 587 };