/* * VMware Screen Codec (VMnc) decoder * Copyright (c) 2006 Konstantin Shishkov * * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; 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++) { int rect_x, rect_y, rect_w, rect_h; if (color) fg = vmnc_get_pixel(gb, bpp, c->bigendian); xy = bytestream2_get_byte(gb); wh = bytestream2_get_byte(gb); rect_x = xy >> 4; rect_y = xy & 0xF; rect_w = (wh >> 4) + 1; rect_h = (wh & 0xF) + 1; if (rect_x + rect_w > w - i || rect_y + rect_h > h - j) { av_log(c->avctx, AV_LOG_ERROR, "Rectangle outside picture\n"); return AVERROR_INVALIDDATA; } paint_rect(dst2, rect_x, rect_y, rect_w, rect_h, 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; c->cur_hx = c->cur_hy = 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; bytestream2_init(gb, buf, buf_size); bytestream2_skip(gb, 2); chunks = bytestream2_get_be16(gb); if (12LL * chunks > bytestream2_get_bytes_left(gb)) return AVERROR_INVALIDDATA; if ((ret = ff_reget_buffer(avctx, c->pic, 0)) < 0) return ret; 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]; } } } while (chunks--) { if (bytestream2_get_bytes_left(gb) < 12) { av_log(avctx, AV_LOG_ERROR, "Premature end of data!\n"); return -1; } 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); 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; } 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 (w*(int64_t)h*c->bpp2 > INT_MAX/2 - 2) { av_log(avctx, AV_LOG_ERROR, "dimensions too large\n"); return AVERROR_INVALIDDATA; } 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_INFO, "Depth mismatch. Container %i bpp, " "Frame data: %i bpp\n", c->bpp, depth); } 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 (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 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; 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, so let's assume they actually meant 32 bits */ c->bpp = 32; case 32: avctx->pix_fmt = AV_PIX_FMT_0RGB32; break; default: av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", c->bpp); return AVERROR_INVALIDDATA; } c->bpp2 = c->bpp / 8; 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_freep(&c->curbits); av_freep(&c->curmask); av_freep(&c->screendta); return 0; } const 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 = AV_CODEC_CAP_DR1, };