Libav
xwddec.c
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1 /*
2  * XWD image format
3  *
4  * Copyright (c) 2012 Paul B Mahol
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "libavutil/imgutils.h"
24 #include "avcodec.h"
25 #include "bytestream.h"
26 #include "internal.h"
27 #include "xwd.h"
28 
29 static int xwd_decode_frame(AVCodecContext *avctx, void *data,
30  int *got_frame, AVPacket *avpkt)
31 {
32  AVFrame *p = data;
33  const uint8_t *buf = avpkt->data;
34  int i, ret, buf_size = avpkt->size;
35  uint32_t version, header_size, vclass, ncolors;
36  uint32_t xoffset, be, bpp, lsize, rsize;
37  uint32_t pixformat, pixdepth, bunit, bitorder, bpad;
38  uint32_t rgb[3];
39  uint8_t *ptr;
40  GetByteContext gb;
41 
42  if (buf_size < XWD_HEADER_SIZE)
43  return AVERROR_INVALIDDATA;
44 
45  bytestream2_init(&gb, buf, buf_size);
46  header_size = bytestream2_get_be32u(&gb);
47 
48  version = bytestream2_get_be32u(&gb);
49  if (version != XWD_VERSION) {
50  av_log(avctx, AV_LOG_ERROR, "unsupported version\n");
51  return AVERROR_INVALIDDATA;
52  }
53 
54  if (buf_size < header_size || header_size < XWD_HEADER_SIZE) {
55  av_log(avctx, AV_LOG_ERROR, "invalid header size\n");
56  return AVERROR_INVALIDDATA;
57  }
58 
59  pixformat = bytestream2_get_be32u(&gb);
60  pixdepth = bytestream2_get_be32u(&gb);
61  avctx->width = bytestream2_get_be32u(&gb);
62  avctx->height = bytestream2_get_be32u(&gb);
63  xoffset = bytestream2_get_be32u(&gb);
64  be = bytestream2_get_be32u(&gb);
65  bunit = bytestream2_get_be32u(&gb);
66  bitorder = bytestream2_get_be32u(&gb);
67  bpad = bytestream2_get_be32u(&gb);
68  bpp = bytestream2_get_be32u(&gb);
69  lsize = bytestream2_get_be32u(&gb);
70  vclass = bytestream2_get_be32u(&gb);
71  rgb[0] = bytestream2_get_be32u(&gb);
72  rgb[1] = bytestream2_get_be32u(&gb);
73  rgb[2] = bytestream2_get_be32u(&gb);
74  bytestream2_skipu(&gb, 8);
75  ncolors = bytestream2_get_be32u(&gb);
76  bytestream2_skipu(&gb, header_size - (XWD_HEADER_SIZE - 20));
77 
78  av_log(avctx, AV_LOG_DEBUG, "pixformat %d, pixdepth %d, bunit %d, bitorder %d, bpad %d\n",
79  pixformat, pixdepth, bunit, bitorder, bpad);
80  av_log(avctx, AV_LOG_DEBUG, "vclass %d, ncolors %d, bpp %d, be %d, lsize %d, xoffset %d\n",
81  vclass, ncolors, bpp, be, lsize, xoffset);
82  av_log(avctx, AV_LOG_DEBUG, "red %0x, green %0x, blue %0x\n", rgb[0], rgb[1], rgb[2]);
83 
84  if (pixformat > XWD_Z_PIXMAP) {
85  av_log(avctx, AV_LOG_ERROR, "invalid pixmap format\n");
86  return AVERROR_INVALIDDATA;
87  }
88 
89  if (pixdepth == 0 || pixdepth > 32) {
90  av_log(avctx, AV_LOG_ERROR, "invalid pixmap depth\n");
91  return AVERROR_INVALIDDATA;
92  }
93 
94  if (xoffset) {
95  avpriv_request_sample(avctx, "xoffset %d", xoffset);
96  return AVERROR_PATCHWELCOME;
97  }
98 
99  if (be > 1) {
100  av_log(avctx, AV_LOG_ERROR, "invalid byte order\n");
101  return AVERROR_INVALIDDATA;
102  }
103 
104  if (bitorder > 1) {
105  av_log(avctx, AV_LOG_ERROR, "invalid bitmap bit order\n");
106  return AVERROR_INVALIDDATA;
107  }
108 
109  if (bunit != 8 && bunit != 16 && bunit != 32) {
110  av_log(avctx, AV_LOG_ERROR, "invalid bitmap unit\n");
111  return AVERROR_INVALIDDATA;
112  }
113 
114  if (bpad != 8 && bpad != 16 && bpad != 32) {
115  av_log(avctx, AV_LOG_ERROR, "invalid bitmap scan-line pad\n");
116  return AVERROR_INVALIDDATA;
117  }
118 
119  if (bpp == 0 || bpp > 32) {
120  av_log(avctx, AV_LOG_ERROR, "invalid bits per pixel\n");
121  return AVERROR_INVALIDDATA;
122  }
123 
124  if (ncolors > 256) {
125  av_log(avctx, AV_LOG_ERROR, "invalid number of entries in colormap\n");
126  return AVERROR_INVALIDDATA;
127  }
128 
129  if ((ret = av_image_check_size(avctx->width, avctx->height, 0, NULL)) < 0)
130  return ret;
131 
132  rsize = FFALIGN(avctx->width * bpp, bpad) / 8;
133  if (lsize < rsize) {
134  av_log(avctx, AV_LOG_ERROR, "invalid bytes per scan-line\n");
135  return AVERROR_INVALIDDATA;
136  }
137 
138  if (bytestream2_get_bytes_left(&gb) < ncolors * XWD_CMAP_SIZE + avctx->height * lsize) {
139  av_log(avctx, AV_LOG_ERROR, "input buffer too small\n");
140  return AVERROR_INVALIDDATA;
141  }
142 
143  if (pixformat != XWD_Z_PIXMAP) {
144  av_log(avctx, AV_LOG_ERROR, "pixmap format %d unsupported\n", pixformat);
145  return AVERROR_PATCHWELCOME;
146  }
147 
148  avctx->pix_fmt = AV_PIX_FMT_NONE;
149  switch (vclass) {
150  case XWD_STATIC_GRAY:
151  case XWD_GRAY_SCALE:
152  if (bpp != 1)
153  return AVERROR_INVALIDDATA;
154  if (pixdepth == 1)
155  avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
156  break;
157  case XWD_STATIC_COLOR:
158  case XWD_PSEUDO_COLOR:
159  if (bpp == 8)
160  avctx->pix_fmt = AV_PIX_FMT_PAL8;
161  break;
162  case XWD_TRUE_COLOR:
163  case XWD_DIRECT_COLOR:
164  if (bpp != 16 && bpp != 24 && bpp != 32)
165  return AVERROR_INVALIDDATA;
166  if (bpp == 16 && pixdepth == 15) {
167  if (rgb[0] == 0x7C00 && rgb[1] == 0x3E0 && rgb[2] == 0x1F)
169  else if (rgb[0] == 0x1F && rgb[1] == 0x3E0 && rgb[2] == 0x7C00)
171  } else if (bpp == 16 && pixdepth == 16) {
172  if (rgb[0] == 0xF800 && rgb[1] == 0x7E0 && rgb[2] == 0x1F)
174  else if (rgb[0] == 0x1F && rgb[1] == 0x7E0 && rgb[2] == 0xF800)
176  } else if (bpp == 24) {
177  if (rgb[0] == 0xFF0000 && rgb[1] == 0xFF00 && rgb[2] == 0xFF)
178  avctx->pix_fmt = be ? AV_PIX_FMT_RGB24 : AV_PIX_FMT_BGR24;
179  else if (rgb[0] == 0xFF && rgb[1] == 0xFF00 && rgb[2] == 0xFF0000)
180  avctx->pix_fmt = be ? AV_PIX_FMT_BGR24 : AV_PIX_FMT_RGB24;
181  } else if (bpp == 32) {
182  if (rgb[0] == 0xFF0000 && rgb[1] == 0xFF00 && rgb[2] == 0xFF)
183  avctx->pix_fmt = be ? AV_PIX_FMT_ARGB : AV_PIX_FMT_BGRA;
184  else if (rgb[0] == 0xFF && rgb[1] == 0xFF00 && rgb[2] == 0xFF0000)
185  avctx->pix_fmt = be ? AV_PIX_FMT_ABGR : AV_PIX_FMT_RGBA;
186  }
187  bytestream2_skipu(&gb, ncolors * XWD_CMAP_SIZE);
188  break;
189  default:
190  av_log(avctx, AV_LOG_ERROR, "invalid visual class\n");
191  return AVERROR_INVALIDDATA;
192  }
193 
194  if (avctx->pix_fmt == AV_PIX_FMT_NONE) {
195  avpriv_request_sample(avctx,
196  "Unknown file: bpp %d, pixdepth %d, vclass %d",
197  bpp, pixdepth, vclass);
198  return AVERROR_PATCHWELCOME;
199  }
200 
201  if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
202  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
203  return ret;
204  }
205 
206  p->key_frame = 1;
208 
209  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
210  uint32_t *dst = (uint32_t *)p->data[1];
211  uint8_t red, green, blue;
212 
213  for (i = 0; i < ncolors; i++) {
214 
215  bytestream2_skipu(&gb, 4); // skip colormap entry number
216  red = bytestream2_get_byteu(&gb);
217  bytestream2_skipu(&gb, 1);
218  green = bytestream2_get_byteu(&gb);
219  bytestream2_skipu(&gb, 1);
220  blue = bytestream2_get_byteu(&gb);
221  bytestream2_skipu(&gb, 3); // skip bitmask flag and padding
222 
223  dst[i] = red << 16 | green << 8 | blue;
224  }
225  }
226 
227  ptr = p->data[0];
228  for (i = 0; i < avctx->height; i++) {
229  bytestream2_get_bufferu(&gb, ptr, rsize);
230  bytestream2_skipu(&gb, lsize - rsize);
231  ptr += p->linesize[0];
232  }
233 
234  *got_frame = 1;
235 
236  return buf_size;
237 }
238 
240  .name = "xwd",
241  .long_name = NULL_IF_CONFIG_SMALL("XWD (X Window Dump) image"),
242  .type = AVMEDIA_TYPE_VIDEO,
243  .id = AV_CODEC_ID_XWD,
244  .decode = xwd_decode_frame,
245  .capabilities = CODEC_CAP_DR1,
246 };