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