/*
* 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;
if ((ret = ff_reget_buffer(avctx, c->pic)) < 0)
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--) {
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;
}
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,
};