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
  35 enum EncTypes {
  36     MAGIC_WMVd = 0x574D5664,
  37     MAGIC_WMVe,
  38     MAGIC_WMVf,
  39     MAGIC_WMVg,
  40     MAGIC_WMVh,
  41     MAGIC_WMVi,
  42     MAGIC_WMVj
  43 };
  44
  45 enum HexTile_Flags {
  46     HT_RAW =  1, // tile is raw
  47     HT_BKG =  2, // background color is present
  48     HT_FG  =  4, // foreground color is present
  49     HT_SUB =  8, // subrects are present
  50     HT_CLR = 16  // each subrect has own color
  51 };
  52
  53 /*
  54  * Decoder context
  55  */
  56 typedef struct VmncContext {
  57     AVCodecContext *avctx;
  58     AVFrame pic;
  59
  60     int bpp;
  61     int bpp2;
  62     int bigendian;
  63     uint8_t pal[768];
  64     int width, height;
  65
  66     /* cursor data */
  67     int cur_w, cur_h;
  68     int cur_x, cur_y;
  69     int cur_hx, cur_hy;
  70     uint8_t* curbits, *curmask;
  71     uint8_t* screendta;
  72 } VmncContext;
  73
  74 /* read pixel value from stream */
  75 static av_always_inline int vmnc_get_pixel(const uint8_t* buf, int bpp, int be) {
  76     switch(bpp * 2 + be) {
  77     case 2:
  78     case 3: return *buf;
  79     case 4: return AV_RL16(buf);
  80     case 5: return AV_RB16(buf);
  81     case 8: return AV_RL32(buf);
  82     case 9: return AV_RB32(buf);
  83     default: return 0;
  84     }
  85 }
  86
  87 static void load_cursor(VmncContext *c, const uint8_t *src)
  88 {
  89     int i, j, p;
  90     const int bpp = c->bpp2;
  91     uint8_t  *dst8  = c->curbits;
  92     uint16_t *dst16 = (uint16_t*)c->curbits;
  93     uint32_t *dst32 = (uint32_t*)c->curbits;
  94
  95     for(j = 0; j < c->cur_h; j++) {
  96         for(i = 0; i < c->cur_w; i++) {
  97             p = vmnc_get_pixel(src, bpp, c->bigendian);
  98             src += bpp;
  99             if(bpp == 1) *dst8++ = p;
 100             if(bpp == 2) *dst16++ = p;
 101             if(bpp == 4) *dst32++ = p;
 102         }
 103     }
 104     dst8 = c->curmask;
 105     dst16 = (uint16_t*)c->curmask;
 106     dst32 = (uint32_t*)c->curmask;
 107     for(j = 0; j < c->cur_h; j++) {
 108         for(i = 0; i < c->cur_w; i++) {
 109             p = vmnc_get_pixel(src, bpp, c->bigendian);
 110             src += bpp;
 111             if(bpp == 1) *dst8++ = p;
 112             if(bpp == 2) *dst16++ = p;
 113             if(bpp == 4) *dst32++ = p;
 114         }
 115     }
 116 }
 117
 118 static void put_cursor(uint8_t *dst, int stride, VmncContext *c, int dx, int dy)
 119 {
 120     int i, j;
 121     int w, h, x, y;
 122     w = c->cur_w;
 123     if(c->width < c->cur_x + c->cur_w) w = c->width - c->cur_x;
 124     h = c->cur_h;
 125     if(c->height < c->cur_y + c->cur_h) h = c->height - c->cur_y;
 126     x = c->cur_x;
 127     y = c->cur_y;
 128     if(x < 0) {
 129         w += x;
 130         x = 0;
 131     }
 132     if(y < 0) {
 133         h += y;
 134         y = 0;
 135     }
 136
 137     if((w < 1) || (h < 1)) return;
 138     dst += x * c->bpp2 + y * stride;
 139
 140     if(c->bpp2 == 1) {
 141         uint8_t* cd = c->curbits, *msk = c->curmask;
 142         for(j = 0; j < h; j++) {
 143             for(i = 0; i < w; i++)
 144                 dst[i] = (dst[i] & cd[i]) ^ msk[i];
 145             msk += c->cur_w;
 146             cd += c->cur_w;
 147             dst += stride;
 148         }
 149     } else if(c->bpp2 == 2) {
 150         uint16_t* cd = (uint16_t*)c->curbits, *msk = (uint16_t*)c->curmask;
 151         uint16_t* dst2;
 152         for(j = 0; j < h; j++) {
 153             dst2 = (uint16_t*)dst;
 154             for(i = 0; i < w; i++)
 155                 dst2[i] = (dst2[i] & cd[i]) ^ msk[i];
 156             msk += c->cur_w;
 157             cd += c->cur_w;
 158             dst += stride;
 159         }
 160     } else if(c->bpp2 == 4) {
 161         uint32_t* cd = (uint32_t*)c->curbits, *msk = (uint32_t*)c->curmask;
 162         uint32_t* dst2;
 163         for(j = 0; j < h; j++) {
 164             dst2 = (uint32_t*)dst;
 165             for(i = 0; i < w; i++)
 166                 dst2[i] = (dst2[i] & cd[i]) ^ msk[i];
 167             msk += c->cur_w;
 168             cd += c->cur_w;
 169             dst += stride;
 170         }
 171     }
 172 }
 173
 174 /* fill rectangle with given color */
 175 static av_always_inline void paint_rect(uint8_t *dst, int dx, int dy, int w, int h, int color, int bpp, int stride)
 176 {
 177     int i, j;
 178     dst += dx * bpp + dy * stride;
 179     if(bpp == 1){
 180         for(j = 0; j < h; j++) {
 181             memset(dst, color, w);
 182             dst += stride;
 183         }
 184     }else if(bpp == 2){
 185         uint16_t* dst2;
 186         for(j = 0; j < h; j++) {
 187             dst2 = (uint16_t*)dst;
 188             for(i = 0; i < w; i++) {
 189                 *dst2++ = color;
 190             }
 191             dst += stride;
 192         }
 193     }else if(bpp == 4){
 194         uint32_t* dst2;
 195         for(j = 0; j < h; j++) {
 196             dst2 = (uint32_t*)dst;
 197             for(i = 0; i < w; i++) {
 198                 dst2[i] = color;
 199             }
 200             dst += stride;
 201         }
 202     }
 203 }
 204
 205 static av_always_inline void paint_raw(uint8_t *dst, int w, int h, const uint8_t* src, int bpp, int be, int stride)
 206 {
 207     int i, j, p;
 208     for(j = 0; j < h; j++) {
 209         for(i = 0; i < w; i++) {
 210             p = vmnc_get_pixel(src, bpp, be);
 211             src += bpp;
 212             switch(bpp){
 213             case 1:
 214                 dst[i] = p;
 215                 break;
 216             case 2:
 217                 ((uint16_t*)dst)[i] = p;
 218                 break;
 219             case 4:
 220                 ((uint32_t*)dst)[i] = p;
 221                 break;
 222             }
 223         }
 224         dst += stride;
 225     }
 226 }
 227
 228 static int decode_hextile(VmncContext *c, uint8_t* dst, const uint8_t* src, int ssize, int w, int h, int stride)
 229 {
 230     int i, j, k;
 231     int bg = 0, fg = 0, rects, color, flags, xy, wh;
 232     const int bpp = c->bpp2;
 233     uint8_t *dst2;
 234     int bw = 16, bh = 16;
 235     const uint8_t *ssrc=src;
 236
 237     for(j = 0; j < h; j += 16) {
 238         dst2 = dst;
 239         bw = 16;
 240         if(j + 16 > h) bh = h - j;
 241         for(i = 0; i < w; i += 16, dst2 += 16 * bpp) {
 242             if(src - ssrc >= ssize) {
 243                 av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
 244                 return -1;
 245             }
 246             if(i + 16 > w) bw = w - i;
 247             flags = *src++;
 248             if(flags & HT_RAW) {
 249                 if(src - ssrc > ssize - bw * bh * bpp) {
 250                     av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
 251                     return -1;
 252                 }
 253                 paint_raw(dst2, bw, bh, src, bpp, c->bigendian, stride);
 254                 src += bw * bh * bpp;
 255             } else {
 256                 if(flags & HT_BKG) {
 257                     bg = vmnc_get_pixel(src, bpp, c->bigendian); src += bpp;
 258                 }
 259                 if(flags & HT_FG) {
 260                     fg = vmnc_get_pixel(src, bpp, c->bigendian); src += bpp;
 261                 }
 262                 rects = 0;
 263                 if(flags & HT_SUB)
 264                     rects = *src++;
 265                 color = !!(flags & HT_CLR);
 266
 267                 paint_rect(dst2, 0, 0, bw, bh, bg, bpp, stride);
 268
 269                 if(src - ssrc > ssize - rects * (color * bpp + 2)) {
 270                     av_log(c->avctx, AV_LOG_ERROR, "Premature end of data!\n");
 271                     return -1;
 272                 }
 273                 for(k = 0; k < rects; k++) {
 274                     if(color) {
 275                         fg = vmnc_get_pixel(src, bpp, c->bigendian); src += bpp;
 276                     }
 277                     xy = *src++;
 278                     wh = *src++;
 279                     paint_rect(dst2, xy >> 4, xy & 0xF, (wh>>4)+1, (wh & 0xF)+1, fg, bpp, stride);
 280                 }
 281             }
 282         }
 283         dst += stride * 16;
 284     }
 285     return src - ssrc;
 286 }
 287
 288 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
 289                         AVPacket *avpkt)
 290 {
 291     const uint8_t *buf = avpkt->data;
 292     int buf_size = avpkt->size;
 293     VmncContext * const c = avctx->priv_data;
 294     uint8_t *outptr;
 295     const uint8_t *src = buf;
 296     int dx, dy, w, h, depth, enc, chunks, res, size_left;
 297
 298     c->pic.reference = 1;
 299     c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
 300     if(avctx->reget_buffer(avctx, &c->pic) < 0){
 301         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 302         return -1;
 303     }
 304
 305     c->pic.key_frame = 0;
 306     c->pic.pict_type = AV_PICTURE_TYPE_P;
 307
 308     //restore screen after cursor
 309     if(c->screendta) {
 310         int i;
 311         w = c->cur_w;
 312         if(c->width < c->cur_x + w) w = c->width - c->cur_x;
 313         h = c->cur_h;
 314         if(c->height < c->cur_y + h) h = c->height - c->cur_y;
 315         dx = c->cur_x;
 316         if(dx < 0) {
 317             w += dx;
 318             dx = 0;
 319         }
 320         dy = c->cur_y;
 321         if(dy < 0) {
 322             h += dy;
 323             dy = 0;
 324         }
 325         if((w > 0) && (h > 0)) {
 326             outptr = c->pic.data[0] + dx * c->bpp2 + dy * c->pic.linesize[0];
 327             for(i = 0; i < h; i++) {
 328                 memcpy(outptr, c->screendta + i * c->cur_w * c->bpp2, w * c->bpp2);
 329                 outptr += c->pic.linesize[0];
 330             }
 331         }
 332     }
 333     src += 2;
 334     chunks = AV_RB16(src); src += 2;
 335     while(chunks--) {
 336         dx = AV_RB16(src); src += 2;
 337         dy = AV_RB16(src); src += 2;
 338         w  = AV_RB16(src); src += 2;
 339         h  = AV_RB16(src); src += 2;
 340         enc = AV_RB32(src); src += 4;
 341         outptr = c->pic.data[0] + dx * c->bpp2 + dy * c->pic.linesize[0];
 342         size_left = buf_size - (src - buf);
 343         switch(enc) {
 344         case MAGIC_WMVd: // cursor
 345             if(size_left < 2 + w * h * c->bpp2 * 2) {
 346                 av_log(avctx, AV_LOG_ERROR, "Premature end of data! (need %i got %i)\n", 2 + w * h * c->bpp2 * 2, size_left);
 347                 return -1;
 348             }
 349             src += 2;
 350             c->cur_w = w;
 351             c->cur_h = h;
 352             c->cur_hx = dx;
 353             c->cur_hy = dy;
 354             if((c->cur_hx > c->cur_w) || (c->cur_hy > c->cur_h)) {
 355                 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);
 356                 c->cur_hx = c->cur_hy = 0;
 357             }
 358             c->curbits = av_realloc(c->curbits, c->cur_w * c->cur_h * c->bpp2);
 359             c->curmask = av_realloc(c->curmask, c->cur_w * c->cur_h * c->bpp2);
 360             c->screendta = av_realloc(c->screendta, c->cur_w * c->cur_h * c->bpp2);
 361             load_cursor(c, src);
 362             src += w * h * c->bpp2 * 2;
 363             break;
 364         case MAGIC_WMVe: // unknown
 365             src += 2;
 366             break;
 367         case MAGIC_WMVf: // update cursor position
 368             c->cur_x = dx - c->cur_hx;
 369             c->cur_y = dy - c->cur_hy;
 370             break;
 371         case MAGIC_WMVg: // unknown
 372             src += 10;
 373             break;
 374         case MAGIC_WMVh: // unknown
 375             src += 4;
 376             break;
 377         case MAGIC_WMVi: // ServerInitialization struct
 378             c->pic.key_frame = 1;
 379             c->pic.pict_type = AV_PICTURE_TYPE_I;
 380             depth = *src++;
 381             if(depth != c->bpp) {
 382                 av_log(avctx, AV_LOG_INFO, "Depth mismatch. Container %i bpp, Frame data: %i bpp\n", c->bpp, depth);
 383             }
 384             src++;
 385             c->bigendian = *src++;
 386             if(c->bigendian & (~1)) {
 387                 av_log(avctx, AV_LOG_INFO, "Invalid header: bigendian flag = %i\n", c->bigendian);
 388                 return -1;
 389             }
 390             //skip the rest of pixel format data
 391             src += 13;
 392             break;
 393         case MAGIC_WMVj: // unknown
 394             src += 2;
 395             break;
 396         case 0x00000000: // raw rectangle data
 397             if((dx + w > c->width) || (dy + h > c->height)) {
 398                 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);
 399                 return -1;
 400             }
 401             if(size_left < w * h * c->bpp2) {
 402                 av_log(avctx, AV_LOG_ERROR, "Premature end of data! (need %i got %i)\n", w * h * c->bpp2, size_left);
 403                 return -1;
 404             }
 405             paint_raw(outptr, w, h, src, c->bpp2, c->bigendian, c->pic.linesize[0]);
 406             src += w * h * c->bpp2;
 407             break;
 408         case 0x00000005: // HexTile encoded rectangle
 409             if((dx + w > c->width) || (dy + h > c->height)) {
 410                 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);
 411                 return -1;
 412             }
 413             res = decode_hextile(c, outptr, src, size_left, w, h, c->pic.linesize[0]);
 414             if(res < 0)
 415                 return -1;
 416             src += res;
 417             break;
 418         default:
 419             av_log(avctx, AV_LOG_ERROR, "Unsupported block type 0x%08X\n", enc);
 420             chunks = 0; // leave chunks decoding loop
 421         }
 422     }
 423     if(c->screendta){
 424         int i;
 425         //save screen data before painting cursor
 426         w = c->cur_w;
 427         if(c->width < c->cur_x + w) w = c->width - c->cur_x;
 428         h = c->cur_h;
 429         if(c->height < c->cur_y + h) h = c->height - c->cur_y;
 430         dx = c->cur_x;
 431         if(dx < 0) {
 432             w += dx;
 433             dx = 0;
 434         }
 435         dy = c->cur_y;
 436         if(dy < 0) {
 437             h += dy;
 438             dy = 0;
 439         }
 440         if((w > 0) && (h > 0)) {
 441             outptr = c->pic.data[0] + dx * c->bpp2 + dy * c->pic.linesize[0];
 442             for(i = 0; i < h; i++) {
 443                 memcpy(c->screendta + i * c->cur_w * c->bpp2, outptr, w * c->bpp2);
 444                 outptr += c->pic.linesize[0];
 445             }
 446             outptr = c->pic.data[0];
 447             put_cursor(outptr, c->pic.linesize[0], c, c->cur_x, c->cur_y);
 448         }
 449     }
 450     *got_frame      = 1;
 451     *(AVFrame*)data = c->pic;
 452
 453     /* always report that the buffer was completely consumed */
 454     return buf_size;
 455 }
 456
 457
 458
 459 /*
 460  *
 461  * Init VMnc decoder
 462  *
 463  */
 464 static av_cold int decode_init(AVCodecContext *avctx)
 465 {
 466     VmncContext * const c = avctx->priv_data;
 467
 468     c->avctx = avctx;
 469
 470     c->width = avctx->width;
 471     c->height = avctx->height;
 472
 473     c->bpp = avctx->bits_per_coded_sample;
 474     c->bpp2 = c->bpp/8;
 475
 476     switch(c->bpp){
 477     case 8:
 478         avctx->pix_fmt = AV_PIX_FMT_PAL8;
 479         break;
 480     case 16:
 481         avctx->pix_fmt = AV_PIX_FMT_RGB555;
 482         break;
 483     case 32:
 484         avctx->pix_fmt = AV_PIX_FMT_RGB32;
 485         break;
 486     default:
 487         av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", c->bpp);
 488         return AVERROR_INVALIDDATA;
 489     }
 490
 491     return 0;
 492 }
 493
 494
 495
 496 /*
 497  *
 498  * Uninit VMnc decoder
 499  *
 500  */
 501 static av_cold int decode_end(AVCodecContext *avctx)
 502 {
 503     VmncContext * const c = avctx->priv_data;
 504
 505     if (c->pic.data[0])
 506         avctx->release_buffer(avctx, &c->pic);
 507
 508     av_free(c->curbits);
 509     av_free(c->curmask);
 510     av_free(c->screendta);
 511     return 0;
 512 }
 513
 514 AVCodec ff_vmnc_decoder = {
 515     .name           = "vmnc",
 516     .type           = AVMEDIA_TYPE_VIDEO,
 517     .id             = AV_CODEC_ID_VMNC,
 518     .priv_data_size = sizeof(VmncContext),
 519     .init           = decode_init,
 520     .close          = decode_end,
 521     .decode         = decode_frame,
 522     .capabilities   = CODEC_CAP_DR1,
 523     .long_name      = NULL_IF_CONFIG_SMALL("VMware Screen Codec / VMware Video"),
 524 };