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bmp.c
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1 /*
2  * BMP image format decoder
3  * Copyright (c) 2005 Mans Rullgard
4  *
5  * This file is part of FFmpeg.
6  *
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.
11  *
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.
16  *
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
20  */
21 
22 #include <inttypes.h>
23 
24 #include "avcodec.h"
25 #include "bytestream.h"
26 #include "bmp.h"
27 #include "internal.h"
28 #include "msrledec.h"
29 
30 static int bmp_decode_frame(AVCodecContext *avctx,
31  void *data, int *got_frame,
32  AVPacket *avpkt)
33 {
34  const uint8_t *buf = avpkt->data;
35  int buf_size = avpkt->size;
36  AVFrame *p = data;
37  unsigned int fsize, hsize;
38  int width, height;
39  unsigned int depth;
40  BiCompression comp;
41  unsigned int ihsize;
42  int i, j, n, linesize, ret;
43  uint32_t rgb[3] = {0};
44  uint32_t alpha = 0;
45  uint8_t *ptr;
46  int dsize;
47  const uint8_t *buf0 = buf;
48  GetByteContext gb;
49 
50  if (buf_size < 14) {
51  av_log(avctx, AV_LOG_ERROR, "buf size too small (%d)\n", buf_size);
52  return AVERROR_INVALIDDATA;
53  }
54 
55  if (bytestream_get_byte(&buf) != 'B' ||
56  bytestream_get_byte(&buf) != 'M') {
57  av_log(avctx, AV_LOG_ERROR, "bad magic number\n");
58  return AVERROR_INVALIDDATA;
59  }
60 
61  fsize = bytestream_get_le32(&buf);
62  if (buf_size < fsize) {
63  av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %u), trying to decode anyway\n",
64  buf_size, fsize);
65  fsize = buf_size;
66  }
67 
68  buf += 2; /* reserved1 */
69  buf += 2; /* reserved2 */
70 
71  hsize = bytestream_get_le32(&buf); /* header size */
72  ihsize = bytestream_get_le32(&buf); /* more header size */
73  if (ihsize + 14LL > hsize) {
74  av_log(avctx, AV_LOG_ERROR, "invalid header size %u\n", hsize);
75  return AVERROR_INVALIDDATA;
76  }
77 
78  /* sometimes file size is set to some headers size, set a real size in that case */
79  if (fsize == 14 || fsize == ihsize + 14)
80  fsize = buf_size - 2;
81 
82  if (fsize <= hsize) {
83  av_log(avctx, AV_LOG_ERROR,
84  "Declared file size is less than header size (%u < %u)\n",
85  fsize, hsize);
86  return AVERROR_INVALIDDATA;
87  }
88 
89  switch (ihsize) {
90  case 40: // windib
91  case 56: // windib v3
92  case 64: // OS/2 v2
93  case 108: // windib v4
94  case 124: // windib v5
95  width = bytestream_get_le32(&buf);
96  height = bytestream_get_le32(&buf);
97  break;
98  case 12: // OS/2 v1
99  width = bytestream_get_le16(&buf);
100  height = bytestream_get_le16(&buf);
101  break;
102  default:
103  av_log(avctx, AV_LOG_ERROR, "unsupported BMP file, patch welcome\n");
104  return AVERROR_PATCHWELCOME;
105  }
106 
107  /* planes */
108  if (bytestream_get_le16(&buf) != 1) {
109  av_log(avctx, AV_LOG_ERROR, "invalid BMP header\n");
110  return AVERROR_INVALIDDATA;
111  }
112 
113  depth = bytestream_get_le16(&buf);
114 
115  if (ihsize >= 40)
116  comp = bytestream_get_le32(&buf);
117  else
118  comp = BMP_RGB;
119 
120  if (comp != BMP_RGB && comp != BMP_BITFIELDS && comp != BMP_RLE4 &&
121  comp != BMP_RLE8) {
122  av_log(avctx, AV_LOG_ERROR, "BMP coding %d not supported\n", comp);
123  return AVERROR_INVALIDDATA;
124  }
125 
126  if (comp == BMP_BITFIELDS) {
127  buf += 20;
128  rgb[0] = bytestream_get_le32(&buf);
129  rgb[1] = bytestream_get_le32(&buf);
130  rgb[2] = bytestream_get_le32(&buf);
131  if (ihsize > 40)
132  alpha = bytestream_get_le32(&buf);
133  }
134 
135  avctx->width = width;
136  avctx->height = height > 0 ? height : -height;
137 
138  avctx->pix_fmt = AV_PIX_FMT_NONE;
139 
140  switch (depth) {
141  case 32:
142  if (comp == BMP_BITFIELDS) {
143  if (rgb[0] == 0xFF000000 && rgb[1] == 0x00FF0000 && rgb[2] == 0x0000FF00)
144  avctx->pix_fmt = alpha ? AV_PIX_FMT_ABGR : AV_PIX_FMT_0BGR;
145  else if (rgb[0] == 0x00FF0000 && rgb[1] == 0x0000FF00 && rgb[2] == 0x000000FF)
146  avctx->pix_fmt = alpha ? AV_PIX_FMT_BGRA : AV_PIX_FMT_BGR0;
147  else if (rgb[0] == 0x0000FF00 && rgb[1] == 0x00FF0000 && rgb[2] == 0xFF000000)
148  avctx->pix_fmt = alpha ? AV_PIX_FMT_ARGB : AV_PIX_FMT_0RGB;
149  else if (rgb[0] == 0x000000FF && rgb[1] == 0x0000FF00 && rgb[2] == 0x00FF0000)
150  avctx->pix_fmt = alpha ? AV_PIX_FMT_RGBA : AV_PIX_FMT_RGB0;
151  else {
152  av_log(avctx, AV_LOG_ERROR, "Unknown bitfields %0X %0X %0X\n", rgb[0], rgb[1], rgb[2]);
153  return AVERROR(EINVAL);
154  }
155  } else {
156  avctx->pix_fmt = AV_PIX_FMT_BGRA;
157  }
158  break;
159  case 24:
160  avctx->pix_fmt = AV_PIX_FMT_BGR24;
161  break;
162  case 16:
163  if (comp == BMP_RGB)
164  avctx->pix_fmt = AV_PIX_FMT_RGB555;
165  else if (comp == BMP_BITFIELDS) {
166  if (rgb[0] == 0xF800 && rgb[1] == 0x07E0 && rgb[2] == 0x001F)
167  avctx->pix_fmt = AV_PIX_FMT_RGB565;
168  else if (rgb[0] == 0x7C00 && rgb[1] == 0x03E0 && rgb[2] == 0x001F)
169  avctx->pix_fmt = AV_PIX_FMT_RGB555;
170  else if (rgb[0] == 0x0F00 && rgb[1] == 0x00F0 && rgb[2] == 0x000F)
171  avctx->pix_fmt = AV_PIX_FMT_RGB444;
172  else {
173  av_log(avctx, AV_LOG_ERROR,
174  "Unknown bitfields %0"PRIX32" %0"PRIX32" %0"PRIX32"\n",
175  rgb[0], rgb[1], rgb[2]);
176  return AVERROR(EINVAL);
177  }
178  }
179  break;
180  case 8:
181  if (hsize - ihsize - 14 > 0)
182  avctx->pix_fmt = AV_PIX_FMT_PAL8;
183  else
184  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
185  break;
186  case 1:
187  case 4:
188  if (hsize - ihsize - 14 > 0) {
189  avctx->pix_fmt = AV_PIX_FMT_PAL8;
190  } else {
191  av_log(avctx, AV_LOG_ERROR, "Unknown palette for %u-colour BMP\n",
192  1 << depth);
193  return AVERROR_INVALIDDATA;
194  }
195  break;
196  default:
197  av_log(avctx, AV_LOG_ERROR, "depth %u not supported\n", depth);
198  return AVERROR_INVALIDDATA;
199  }
200 
201  if (avctx->pix_fmt == AV_PIX_FMT_NONE) {
202  av_log(avctx, AV_LOG_ERROR, "unsupported pixel format\n");
203  return AVERROR_INVALIDDATA;
204  }
205 
206  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
207  return ret;
208  p->pict_type = AV_PICTURE_TYPE_I;
209  p->key_frame = 1;
210 
211  buf = buf0 + hsize;
212  dsize = buf_size - hsize;
213 
214  /* Line size in file multiple of 4 */
215  n = ((avctx->width * depth + 31) / 8) & ~3;
216 
217  if (n * avctx->height > dsize && comp != BMP_RLE4 && comp != BMP_RLE8) {
218  n = (avctx->width * depth + 7) / 8;
219  if (n * avctx->height > dsize) {
220  av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
221  dsize, n * avctx->height);
222  return AVERROR_INVALIDDATA;
223  }
224  av_log(avctx, AV_LOG_ERROR, "data size too small, assuming missing line alignment\n");
225  }
226 
227  // RLE may skip decoding some picture areas, so blank picture before decoding
228  if (comp == BMP_RLE4 || comp == BMP_RLE8)
229  memset(p->data[0], 0, avctx->height * p->linesize[0]);
230 
231  if (height > 0) {
232  ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
233  linesize = -p->linesize[0];
234  } else {
235  ptr = p->data[0];
236  linesize = p->linesize[0];
237  }
238 
239  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
240  int colors = 1 << depth;
241 
242  memset(p->data[1], 0, 1024);
243 
244  if (ihsize >= 36) {
245  int t;
246  buf = buf0 + 46;
247  t = bytestream_get_le32(&buf);
248  if (t < 0 || t > (1 << depth)) {
249  av_log(avctx, AV_LOG_ERROR,
250  "Incorrect number of colors - %X for bitdepth %u\n",
251  t, depth);
252  } else if (t) {
253  colors = t;
254  }
255  } else {
256  colors = FFMIN(256, (hsize-ihsize-14) / 3);
257  }
258  buf = buf0 + 14 + ihsize; //palette location
259  // OS/2 bitmap, 3 bytes per palette entry
260  if ((hsize-ihsize-14) < (colors << 2)) {
261  if ((hsize-ihsize-14) < colors * 3) {
262  av_log(avctx, AV_LOG_ERROR, "palette doesn't fit in packet\n");
263  return AVERROR_INVALIDDATA;
264  }
265  for (i = 0; i < colors; i++)
266  ((uint32_t*)p->data[1])[i] = (0xFFU<<24) | bytestream_get_le24(&buf);
267  } else {
268  for (i = 0; i < colors; i++)
269  ((uint32_t*)p->data[1])[i] = 0xFFU << 24 | bytestream_get_le32(&buf);
270  }
271  buf = buf0 + hsize;
272  }
273  if (comp == BMP_RLE4 || comp == BMP_RLE8) {
274  if (comp == BMP_RLE8 && height < 0) {
275  p->data[0] += p->linesize[0] * (avctx->height - 1);
276  p->linesize[0] = -p->linesize[0];
277  }
278  bytestream2_init(&gb, buf, dsize);
279  ff_msrle_decode(avctx, (AVPicture*)p, depth, &gb);
280  if (height < 0) {
281  p->data[0] += p->linesize[0] * (avctx->height - 1);
282  p->linesize[0] = -p->linesize[0];
283  }
284  } else {
285  switch (depth) {
286  case 1:
287  for (i = 0; i < avctx->height; i++) {
288  int j;
289  for (j = 0; j < n; j++) {
290  ptr[j*8+0] = buf[j] >> 7;
291  ptr[j*8+1] = (buf[j] >> 6) & 1;
292  ptr[j*8+2] = (buf[j] >> 5) & 1;
293  ptr[j*8+3] = (buf[j] >> 4) & 1;
294  ptr[j*8+4] = (buf[j] >> 3) & 1;
295  ptr[j*8+5] = (buf[j] >> 2) & 1;
296  ptr[j*8+6] = (buf[j] >> 1) & 1;
297  ptr[j*8+7] = buf[j] & 1;
298  }
299  buf += n;
300  ptr += linesize;
301  }
302  break;
303  case 8:
304  case 24:
305  case 32:
306  for (i = 0; i < avctx->height; i++) {
307  memcpy(ptr, buf, n);
308  buf += n;
309  ptr += linesize;
310  }
311  break;
312  case 4:
313  for (i = 0; i < avctx->height; i++) {
314  int j;
315  for (j = 0; j < n; j++) {
316  ptr[j*2+0] = (buf[j] >> 4) & 0xF;
317  ptr[j*2+1] = buf[j] & 0xF;
318  }
319  buf += n;
320  ptr += linesize;
321  }
322  break;
323  case 16:
324  for (i = 0; i < avctx->height; i++) {
325  const uint16_t *src = (const uint16_t *) buf;
326  uint16_t *dst = (uint16_t *) ptr;
327 
328  for (j = 0; j < avctx->width; j++)
329  *dst++ = av_le2ne16(*src++);
330 
331  buf += n;
332  ptr += linesize;
333  }
334  break;
335  default:
336  av_log(avctx, AV_LOG_ERROR, "BMP decoder is broken\n");
337  return AVERROR_INVALIDDATA;
338  }
339  }
340 
341  *got_frame = 1;
342 
343  return buf_size;
344 }
345 
346 AVCodec ff_bmp_decoder = {
347  .name = "bmp",
348  .long_name = NULL_IF_CONFIG_SMALL("BMP (Windows and OS/2 bitmap)"),
349  .type = AVMEDIA_TYPE_VIDEO,
350  .id = AV_CODEC_ID_BMP,
351  .decode = bmp_decode_frame,
352  .capabilities = CODEC_CAP_DR1,
353 };
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