2 * VMware Screen Codec (VMnc) decoder
3 * Copyright (c) 2006 Konstantin Shishkov
5 * This file is part of FFmpeg.
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.
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.
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
24 * VMware Screen Codec (VMnc) decoder
25 * As Alex Beregszaszi discovered, this is effectively RFB data dump
31 #include "libavutil/common.h"
32 #include "libavutil/intreadwrite.h"
35 #include "bytestream.h"
38 MAGIC_WMVd = 0x574D5664,
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
58 typedef struct VmncContext {
59 AVCodecContext *avctx;
73 uint8_t *curbits, *curmask;
77 /* read pixel value from stream */
78 static av_always_inline int vmnc_get_pixel(GetByteContext *gb, int bpp, int be)
80 switch (bpp * 2 + be) {
83 return bytestream2_get_byte(gb);
85 return bytestream2_get_le16(gb);
87 return bytestream2_get_be16(gb);
89 return bytestream2_get_le32(gb);
91 return bytestream2_get_be32(gb);
96 static void load_cursor(VmncContext *c)
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;
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);
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);
131 static void put_cursor(uint8_t *dst, int stride, VmncContext *c, int dx, int dy)
136 if (c->width < c->cur_x + c->cur_w)
137 w = c->width - c->cur_x;
139 if (c->height < c->cur_y + c->cur_h)
140 h = c->height - c->cur_y;
152 if ((w < 1) || (h < 1))
154 dst += x * c->bpp2 + y * stride;
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];
165 } else if (c->bpp2 == 2) {
166 uint16_t *cd = (uint16_t*)c->curbits, *msk = (uint16_t*)c->curmask;
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];
176 } else if (c->bpp2 == 4) {
177 uint32_t *cd = (uint32_t*)c->curbits, *msk = (uint32_t*)c->curmask;
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];
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,
196 dst += dx * bpp + dy * stride;
198 for (j = 0; j < h; j++) {
199 memset(dst, color, w);
202 } else if (bpp == 2) {
204 for (j = 0; j < h; j++) {
205 dst2 = (uint16_t*)dst;
206 for (i = 0; i < w; i++)
210 } else if (bpp == 4) {
212 for (j = 0; j < h; j++) {
213 dst2 = (uint32_t*)dst;
214 for (i = 0; i < w; i++)
221 static av_always_inline void paint_raw(uint8_t *dst, int w, int h,
222 GetByteContext *gb, int bpp,
226 for (j = 0; j < h; j++) {
227 for (i = 0; i < w; i++) {
228 p = vmnc_get_pixel(gb, bpp, be);
234 ((uint16_t*)dst)[i] = p;
237 ((uint32_t*)dst)[i] = p;
245 static int decode_hextile(VmncContext *c, uint8_t* dst, GetByteContext *gb,
246 int w, int h, int stride)
249 int bg = 0, fg = 0, rects, color, flags, xy, wh;
250 const int bpp = c->bpp2;
252 int bw = 16, bh = 16;
254 for (j = 0; j < h; j += 16) {
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;
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;
272 paint_raw(dst2, bw, bh, gb, bpp, c->bigendian, stride);
275 bg = vmnc_get_pixel(gb, bpp, c->bigendian);
277 fg = vmnc_get_pixel(gb, bpp, c->bigendian);
280 rects = bytestream2_get_byte(gb);
281 color = !!(flags & HT_CLR);
283 paint_rect(dst2, 0, 0, bw, bh, bg, bpp, stride);
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;
289 for (k = 0; k < rects; k++) {
290 int rect_x, rect_y, rect_w, rect_h;
292 fg = vmnc_get_pixel(gb, bpp, c->bigendian);
293 xy = bytestream2_get_byte(gb);
294 wh = bytestream2_get_byte(gb);
298 rect_w = (wh >> 4) + 1;
299 rect_h = (wh & 0xF) + 1;
301 if (rect_x + rect_w > w - i || rect_y + rect_h > h - j) {
302 av_log(c->avctx, AV_LOG_ERROR, "Rectangle outside picture\n");
303 return AVERROR_INVALIDDATA;
306 paint_rect(dst2, rect_x, rect_y,
307 rect_w, rect_h, fg, bpp, stride);
316 static void reset_buffers(VmncContext *c)
318 av_freep(&c->curbits);
319 av_freep(&c->curmask);
320 av_freep(&c->screendta);
321 c->cur_w = c->cur_h = 0;
322 c->cur_hx = c->cur_hy = 0;
326 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
329 const uint8_t *buf = avpkt->data;
330 int buf_size = avpkt->size;
331 VmncContext * const c = avctx->priv_data;
332 GetByteContext *gb = &c->gb;
334 int dx, dy, w, h, depth, enc, chunks, res, size_left, ret;
336 bytestream2_init(gb, buf, buf_size);
337 bytestream2_skip(gb, 2);
338 chunks = bytestream2_get_be16(gb);
339 if (12LL * chunks > bytestream2_get_bytes_left(gb))
340 return AVERROR_INVALIDDATA;
342 if ((ret = ff_reget_buffer(avctx, c->pic, 0)) < 0)
345 c->pic->key_frame = 0;
346 c->pic->pict_type = AV_PICTURE_TYPE_P;
348 // restore screen after cursor
352 if (c->width < c->cur_x + w)
353 w = c->width - c->cur_x;
355 if (c->height < c->cur_y + h)
356 h = c->height - c->cur_y;
367 if ((w > 0) && (h > 0)) {
368 outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
369 for (i = 0; i < h; i++) {
370 memcpy(outptr, c->screendta + i * c->cur_w * c->bpp2,
372 outptr += c->pic->linesize[0];
378 if (bytestream2_get_bytes_left(gb) < 12) {
379 av_log(avctx, AV_LOG_ERROR, "Premature end of data!\n");
382 dx = bytestream2_get_be16(gb);
383 dy = bytestream2_get_be16(gb);
384 w = bytestream2_get_be16(gb);
385 h = bytestream2_get_be16(gb);
386 enc = bytestream2_get_be32(gb);
387 if ((dx + w > c->width) || (dy + h > c->height)) {
388 av_log(avctx, AV_LOG_ERROR,
389 "Incorrect frame size: %ix%i+%ix%i of %ix%i\n",
390 w, h, dx, dy, c->width, c->height);
391 return AVERROR_INVALIDDATA;
393 outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
394 size_left = bytestream2_get_bytes_left(gb);
396 case MAGIC_WMVd: // cursor
397 if (w*(int64_t)h*c->bpp2 > INT_MAX/2 - 2) {
398 av_log(avctx, AV_LOG_ERROR, "dimensions too large\n");
399 return AVERROR_INVALIDDATA;
401 if (size_left < 2 + w * h * c->bpp2 * 2) {
402 av_log(avctx, AV_LOG_ERROR,
403 "Premature end of data! (need %i got %i)\n",
404 2 + w * h * c->bpp2 * 2, size_left);
405 return AVERROR_INVALIDDATA;
407 bytestream2_skip(gb, 2);
412 if ((c->cur_hx > c->cur_w) || (c->cur_hy > c->cur_h)) {
413 av_log(avctx, AV_LOG_ERROR,
414 "Cursor hot spot is not in image: "
415 "%ix%i of %ix%i cursor size\n",
416 c->cur_hx, c->cur_hy, c->cur_w, c->cur_h);
417 c->cur_hx = c->cur_hy = 0;
419 if (c->cur_w * c->cur_h >= INT_MAX / c->bpp2) {
421 return AVERROR(EINVAL);
423 int screen_size = c->cur_w * c->cur_h * c->bpp2;
424 if ((ret = av_reallocp(&c->curbits, screen_size)) < 0 ||
425 (ret = av_reallocp(&c->curmask, screen_size)) < 0 ||
426 (ret = av_reallocp(&c->screendta, screen_size)) < 0) {
433 case MAGIC_WMVe: // unknown
434 bytestream2_skip(gb, 2);
436 case MAGIC_WMVf: // update cursor position
437 c->cur_x = dx - c->cur_hx;
438 c->cur_y = dy - c->cur_hy;
440 case MAGIC_WMVg: // unknown
441 bytestream2_skip(gb, 10);
443 case MAGIC_WMVh: // unknown
444 bytestream2_skip(gb, 4);
446 case MAGIC_WMVi: // ServerInitialization struct
447 c->pic->key_frame = 1;
448 c->pic->pict_type = AV_PICTURE_TYPE_I;
449 depth = bytestream2_get_byte(gb);
450 if (depth != c->bpp) {
451 av_log(avctx, AV_LOG_INFO,
452 "Depth mismatch. Container %i bpp, "
453 "Frame data: %i bpp\n",
456 bytestream2_skip(gb, 1);
457 c->bigendian = bytestream2_get_byte(gb);
458 if (c->bigendian & (~1)) {
459 av_log(avctx, AV_LOG_INFO,
460 "Invalid header: bigendian flag = %i\n", c->bigendian);
461 return AVERROR_INVALIDDATA;
463 //skip the rest of pixel format data
464 bytestream2_skip(gb, 13);
466 case MAGIC_WMVj: // unknown
467 bytestream2_skip(gb, 2);
469 case 0x00000000: // raw rectangle data
470 if (size_left < w * h * c->bpp2) {
471 av_log(avctx, AV_LOG_ERROR,
472 "Premature end of data! (need %i got %i)\n",
473 w * h * c->bpp2, size_left);
474 return AVERROR_INVALIDDATA;
476 paint_raw(outptr, w, h, gb, c->bpp2, c->bigendian,
477 c->pic->linesize[0]);
479 case 0x00000005: // HexTile encoded rectangle
480 res = decode_hextile(c, outptr, gb, w, h, c->pic->linesize[0]);
485 av_log(avctx, AV_LOG_ERROR, "Unsupported block type 0x%08X\n", enc);
486 chunks = 0; // leave chunks decoding loop
491 // save screen data before painting cursor
493 if (c->width < c->cur_x + w)
494 w = c->width - c->cur_x;
496 if (c->height < c->cur_y + h)
497 h = c->height - c->cur_y;
508 if ((w > 0) && (h > 0)) {
509 outptr = c->pic->data[0] + dx * c->bpp2 + dy * c->pic->linesize[0];
510 for (i = 0; i < h; i++) {
511 memcpy(c->screendta + i * c->cur_w * c->bpp2, outptr,
513 outptr += c->pic->linesize[0];
515 outptr = c->pic->data[0];
516 put_cursor(outptr, c->pic->linesize[0], c, c->cur_x, c->cur_y);
520 if ((ret = av_frame_ref(data, c->pic)) < 0)
523 /* always report that the buffer was completely consumed */
527 static av_cold int decode_init(AVCodecContext *avctx)
529 VmncContext * const c = avctx->priv_data;
532 c->width = avctx->width;
533 c->height = avctx->height;
534 c->bpp = avctx->bits_per_coded_sample;
538 avctx->pix_fmt = AV_PIX_FMT_PAL8;
541 avctx->pix_fmt = AV_PIX_FMT_RGB555;
544 /* 24 bits is not technically supported, but some clients might
545 * mistakenly set it, so let's assume they actually meant 32 bits */
548 avctx->pix_fmt = AV_PIX_FMT_0RGB32;
551 av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", c->bpp);
552 return AVERROR_INVALIDDATA;
554 c->bpp2 = c->bpp / 8;
556 c->pic = av_frame_alloc();
558 return AVERROR(ENOMEM);
563 static av_cold int decode_end(AVCodecContext *avctx)
565 VmncContext * const c = avctx->priv_data;
567 av_frame_free(&c->pic);
569 av_freep(&c->curbits);
570 av_freep(&c->curmask);
571 av_freep(&c->screendta);
575 AVCodec ff_vmnc_decoder = {
577 .long_name = NULL_IF_CONFIG_SMALL("VMware Screen Codec / VMware Video"),
578 .type = AVMEDIA_TYPE_VIDEO,
579 .id = AV_CODEC_ID_VMNC,
580 .priv_data_size = sizeof(VmncContext),
583 .decode = decode_frame,
584 .capabilities = AV_CODEC_CAP_DR1,