FFmpeg
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 "codec_internal.h"
28 #include "decode.h"
29 #include "msrledec.h"
30 
31 static int bmp_decode_frame(AVCodecContext *avctx, AVFrame *p,
32  int *got_frame, AVPacket *avpkt)
33 {
34  const uint8_t *buf = avpkt->data;
35  int buf_size = avpkt->size;
36  unsigned int fsize, hsize;
37  int width, height;
38  unsigned int depth;
39  BiCompression comp;
40  unsigned int ihsize;
41  int i, j, n, linesize, ret;
42  uint32_t rgb[3] = {0};
43  uint32_t alpha = 0;
44  uint8_t *ptr;
45  int dsize;
46  const uint8_t *buf0 = buf;
47  GetByteContext gb;
48 
49  if (buf_size < 14) {
50  av_log(avctx, AV_LOG_ERROR, "buf size too small (%d)\n", buf_size);
51  return AVERROR_INVALIDDATA;
52  }
53 
54  if (bytestream_get_byte(&buf) != 'B' ||
55  bytestream_get_byte(&buf) != 'M') {
56  av_log(avctx, AV_LOG_ERROR, "bad magic number\n");
57  return AVERROR_INVALIDDATA;
58  }
59 
60  fsize = bytestream_get_le32(&buf);
61  if (buf_size < fsize) {
62  av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %u), trying to decode anyway\n",
63  buf_size, fsize);
64  fsize = buf_size;
65  }
66 
67  buf += 2; /* reserved1 */
68  buf += 2; /* reserved2 */
69 
70  hsize = bytestream_get_le32(&buf); /* header size */
71  ihsize = bytestream_get_le32(&buf); /* more header size */
72  if (ihsize + 14LL > hsize) {
73  av_log(avctx, AV_LOG_ERROR, "invalid header size %u\n", hsize);
74  return AVERROR_INVALIDDATA;
75  }
76 
77  /* sometimes file size is set to some headers size, set a real size in that case */
78  if (fsize == 14 || fsize == ihsize + 14)
79  fsize = buf_size - 2;
80 
81  if (fsize <= hsize) {
82  av_log(avctx, AV_LOG_ERROR,
83  "Declared file size is less than header size (%u < %u)\n",
84  fsize, hsize);
85  return AVERROR_INVALIDDATA;
86  }
87 
88  switch (ihsize) {
89  case 40: // windib
90  case 56: // windib v3
91  case 64: // OS/2 v2
92  case 108: // windib v4
93  case 124: // windib v5
94  width = bytestream_get_le32(&buf);
95  height = bytestream_get_le32(&buf);
96  break;
97  case 12: // OS/2 v1
98  width = bytestream_get_le16(&buf);
99  height = bytestream_get_le16(&buf);
100  break;
101  default:
102  avpriv_report_missing_feature(avctx, "Information header size %u",
103  ihsize);
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  ret = ff_set_dimensions(avctx, width, height > 0 ? height : -(unsigned)height);
136  if (ret < 0) {
137  av_log(avctx, AV_LOG_ERROR, "Failed to set dimensions %d %d\n", width, height);
138  return AVERROR_INVALIDDATA;
139  }
140 
141  avctx->pix_fmt = AV_PIX_FMT_NONE;
142 
143  switch (depth) {
144  case 32:
145  if (comp == BMP_BITFIELDS) {
146  if (rgb[0] == 0xFF000000 && rgb[1] == 0x00FF0000 && rgb[2] == 0x0000FF00)
147  avctx->pix_fmt = alpha ? AV_PIX_FMT_ABGR : AV_PIX_FMT_0BGR;
148  else if (rgb[0] == 0x00FF0000 && rgb[1] == 0x0000FF00 && rgb[2] == 0x000000FF)
149  avctx->pix_fmt = alpha ? AV_PIX_FMT_BGRA : AV_PIX_FMT_BGR0;
150  else if (rgb[0] == 0x0000FF00 && rgb[1] == 0x00FF0000 && rgb[2] == 0xFF000000)
151  avctx->pix_fmt = alpha ? AV_PIX_FMT_ARGB : AV_PIX_FMT_0RGB;
152  else if (rgb[0] == 0x000000FF && rgb[1] == 0x0000FF00 && rgb[2] == 0x00FF0000)
153  avctx->pix_fmt = alpha ? AV_PIX_FMT_RGBA : AV_PIX_FMT_RGB0;
154  else {
155  av_log(avctx, AV_LOG_ERROR, "Unknown bitfields "
156  "%0"PRIX32" %0"PRIX32" %0"PRIX32"\n", rgb[0], rgb[1], rgb[2]);
157  return AVERROR(EINVAL);
158  }
159  } else {
160  avctx->pix_fmt = AV_PIX_FMT_BGRA;
161  }
162  break;
163  case 24:
164  avctx->pix_fmt = AV_PIX_FMT_BGR24;
165  break;
166  case 16:
167  if (comp == BMP_RGB)
168  avctx->pix_fmt = AV_PIX_FMT_RGB555;
169  else if (comp == BMP_BITFIELDS) {
170  if (rgb[0] == 0xF800 && rgb[1] == 0x07E0 && rgb[2] == 0x001F)
171  avctx->pix_fmt = AV_PIX_FMT_RGB565;
172  else if (rgb[0] == 0x7C00 && rgb[1] == 0x03E0 && rgb[2] == 0x001F)
173  avctx->pix_fmt = AV_PIX_FMT_RGB555;
174  else if (rgb[0] == 0x0F00 && rgb[1] == 0x00F0 && rgb[2] == 0x000F)
175  avctx->pix_fmt = AV_PIX_FMT_RGB444;
176  else {
177  av_log(avctx, AV_LOG_ERROR,
178  "Unknown bitfields %0"PRIX32" %0"PRIX32" %0"PRIX32"\n",
179  rgb[0], rgb[1], rgb[2]);
180  return AVERROR(EINVAL);
181  }
182  }
183  break;
184  case 8:
185  if (hsize - ihsize - 14 > 0)
186  avctx->pix_fmt = AV_PIX_FMT_PAL8;
187  else
188  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
189  break;
190  case 1:
191  case 4:
192  if (hsize - ihsize - 14 > 0) {
193  avctx->pix_fmt = AV_PIX_FMT_PAL8;
194  } else {
195  av_log(avctx, AV_LOG_ERROR, "Unknown palette for %u-colour BMP\n",
196  1 << depth);
197  return AVERROR_INVALIDDATA;
198  }
199  break;
200  default:
201  av_log(avctx, AV_LOG_ERROR, "depth %u not supported\n", depth);
202  return AVERROR_INVALIDDATA;
203  }
204 
205  if (avctx->pix_fmt == AV_PIX_FMT_NONE) {
206  av_log(avctx, AV_LOG_ERROR, "unsupported pixel format\n");
207  return AVERROR_INVALIDDATA;
208  }
209 
210  buf = buf0 + hsize;
211  dsize = buf_size - hsize;
212 
213  /* Line size in file multiple of 4 */
214  n = ((avctx->width * depth + 31) / 8) & ~3;
215 
216  if (n * avctx->height > dsize && comp != BMP_RLE4 && comp != BMP_RLE8) {
217  n = (avctx->width * depth + 7) / 8;
218  if (n * avctx->height > dsize) {
219  av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
220  dsize, n * avctx->height);
221  return AVERROR_INVALIDDATA;
222  }
223  av_log(avctx, AV_LOG_ERROR, "data size too small, assuming missing line alignment\n");
224  }
225  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
226  return ret;
227 
228  // RLE may skip decoding some picture areas, so blank picture before decoding
229  if (comp == BMP_RLE4 || comp == BMP_RLE8)
230  memset(p->data[0], 0, avctx->height * p->linesize[0]);
231 
232  if (height > 0) {
233  ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
234  linesize = -p->linesize[0];
235  } else {
236  ptr = p->data[0];
237  linesize = p->linesize[0];
238  }
239 
240  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
241  int colors = 1 << depth;
242 
243  memset(p->data[1], 0, 1024);
244 
245  if (ihsize >= 36) {
246  int t;
247  buf = buf0 + 46;
248  t = bytestream_get_le32(&buf);
249  if (t < 0 || t > (1 << depth)) {
250  av_log(avctx, AV_LOG_ERROR,
251  "Incorrect number of colors - %X for bitdepth %u\n",
252  t, depth);
253  } else if (t) {
254  colors = t;
255  }
256  } else {
257  colors = FFMIN(256, (hsize-ihsize-14) / 3);
258  }
259  buf = buf0 + 14 + ihsize; //palette location
260  // OS/2 bitmap, 3 bytes per palette entry
261  if ((hsize-ihsize-14) < (colors << 2)) {
262  if ((hsize-ihsize-14) < colors * 3) {
263  av_log(avctx, AV_LOG_ERROR, "palette doesn't fit in packet\n");
264  return AVERROR_INVALIDDATA;
265  }
266  for (i = 0; i < colors; i++)
267  ((uint32_t*)p->data[1])[i] = (0xFFU<<24) | bytestream_get_le24(&buf);
268  } else {
269  for (i = 0; i < colors; i++)
270  ((uint32_t*)p->data[1])[i] = 0xFFU << 24 | bytestream_get_le32(&buf);
271  }
272  buf = buf0 + hsize;
273  }
274  if (comp == BMP_RLE4 || comp == BMP_RLE8) {
275  if (comp == BMP_RLE8 && height < 0) {
276  p->data[0] += p->linesize[0] * (avctx->height - 1);
277  p->linesize[0] = -p->linesize[0];
278  }
279  bytestream2_init(&gb, buf, dsize);
280  ff_msrle_decode(avctx, p, depth, &gb);
281  if (height < 0) {
282  p->data[0] += p->linesize[0] * (avctx->height - 1);
283  p->linesize[0] = -p->linesize[0];
284  }
285  } else {
286  switch (depth) {
287  case 1:
288  for (i = 0; i < avctx->height; i++) {
289  int j;
290  for (j = 0; j < avctx->width >> 3; j++) {
291  ptr[j*8+0] = buf[j] >> 7;
292  ptr[j*8+1] = (buf[j] >> 6) & 1;
293  ptr[j*8+2] = (buf[j] >> 5) & 1;
294  ptr[j*8+3] = (buf[j] >> 4) & 1;
295  ptr[j*8+4] = (buf[j] >> 3) & 1;
296  ptr[j*8+5] = (buf[j] >> 2) & 1;
297  ptr[j*8+6] = (buf[j] >> 1) & 1;
298  ptr[j*8+7] = buf[j] & 1;
299  }
300  for (j = 0; j < (avctx->width & 7); j++) {
301  ptr[avctx->width - (avctx->width & 7) + j] = buf[avctx->width >> 3] >> (7 - j) & 1;
302  }
303  buf += n;
304  ptr += linesize;
305  }
306  break;
307  case 8:
308  case 24:
309  case 32:
310  for (i = 0; i < avctx->height; i++) {
311  memcpy(ptr, buf, n);
312  buf += n;
313  ptr += linesize;
314  }
315  break;
316  case 4:
317  for (i = 0; i < avctx->height; i++) {
318  int j;
319  for (j = 0; j < n; j++) {
320  ptr[j*2+0] = (buf[j] >> 4) & 0xF;
321  ptr[j*2+1] = buf[j] & 0xF;
322  }
323  buf += n;
324  ptr += linesize;
325  }
326  break;
327  case 16:
328  for (i = 0; i < avctx->height; i++) {
329  const uint16_t *src = (const uint16_t *) buf;
330  uint16_t *dst = (uint16_t *) ptr;
331 
332  for (j = 0; j < avctx->width; j++)
333  *dst++ = av_le2ne16(*src++);
334 
335  buf += n;
336  ptr += linesize;
337  }
338  break;
339  default:
340  av_log(avctx, AV_LOG_ERROR, "BMP decoder is broken\n");
341  return AVERROR_INVALIDDATA;
342  }
343  }
344  if (avctx->pix_fmt == AV_PIX_FMT_BGRA) {
345  for (i = 0; i < avctx->height; i++) {
346  int j;
347  uint8_t *ptr = p->data[0] + p->linesize[0]*i + 3;
348  for (j = 0; j < avctx->width; j++) {
349  if (ptr[4*j])
350  break;
351  }
352  if (j < avctx->width)
353  break;
354  }
355  if (i == avctx->height)
356  avctx->pix_fmt = p->format = AV_PIX_FMT_BGR0;
357  }
358 
359  *got_frame = 1;
360 
361  return buf_size;
362 }
363 
364 const FFCodec ff_bmp_decoder = {
365  .p.name = "bmp",
366  CODEC_LONG_NAME("BMP (Windows and OS/2 bitmap)"),
367  .p.type = AVMEDIA_TYPE_VIDEO,
368  .p.id = AV_CODEC_ID_BMP,
369  .p.capabilities = AV_CODEC_CAP_DR1,
370  FF_CODEC_DECODE_CB(bmp_decode_frame),
371 };
ff_bmp_decoder
const FFCodec ff_bmp_decoder
Definition: bmp.c:364
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
comp
static void comp(unsigned char *dst, ptrdiff_t dst_stride, unsigned char *src, ptrdiff_t src_stride, int add)
Definition: eamad.c:79
GetByteContext
Definition: bytestream.h:33
BMP_RLE4
@ BMP_RLE4
Definition: bmp.h:28
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:427
AVPacket::data
uint8_t * data
Definition: packet.h:588
FFCodec
Definition: codec_internal.h:127
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:76
AV_PIX_FMT_BGRA
@ AV_PIX_FMT_BGRA
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:102
BMP_RGB
@ BMP_RGB
Definition: bmp.h:26
ff_set_dimensions
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:91
rgb
Definition: rpzaenc.c:60
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
bmp_decode_frame
static int bmp_decode_frame(AVCodecContext *avctx, AVFrame *p, int *got_frame, AVPacket *avpkt)
Definition: bmp.c:31
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:210
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:347
AV_CODEC_ID_BMP
@ AV_CODEC_ID_BMP
Definition: codec_id.h:130
decode.h
fsize
static int64_t fsize(FILE *f)
Definition: audiomatch.c:29
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:332
AV_PIX_FMT_RGBA
@ AV_PIX_FMT_RGBA
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:100
bmp.h
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
msrledec.h
AV_PIX_FMT_BGR0
@ AV_PIX_FMT_BGR0
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
Definition: pixfmt.h:265
AV_PIX_FMT_GRAY8
@ AV_PIX_FMT_GRAY8
Y , 8bpp.
Definition: pixfmt.h:81
BiCompression
BiCompression
Definition: bmp.h:25
AV_PIX_FMT_ABGR
@ AV_PIX_FMT_ABGR
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:101
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1729
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:589
height
#define height
Definition: dsp.h:89
codec_internal.h
dst
uint8_t ptrdiff_t const uint8_t ptrdiff_t int intptr_t intptr_t int int16_t * dst
Definition: dsp.h:87
BMP_BITFIELDS
@ BMP_BITFIELDS
Definition: bmp.h:29
avpriv_report_missing_feature
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
av_le2ne16
#define av_le2ne16(x)
Definition: bswap.h:91
AV_PIX_FMT_RGB0
@ AV_PIX_FMT_RGB0
packed RGB 8:8:8, 32bpp, RGBXRGBX... X=unused/undefined
Definition: pixfmt.h:263
AV_PIX_FMT_ARGB
@ AV_PIX_FMT_ARGB
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:99
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
BMP_RLE8
@ BMP_RLE8
Definition: bmp.h:27
AV_PIX_FMT_RGB555
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:527
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:179
AVCodecContext::height
int height
Definition: avcodec.h:600
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:639
AV_PIX_FMT_RGB565
#define AV_PIX_FMT_RGB565
Definition: pixfmt.h:526
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:84
ret
ret
Definition: filter_design.txt:187
AV_PIX_FMT_0BGR
@ AV_PIX_FMT_0BGR
packed BGR 8:8:8, 32bpp, XBGRXBGR... X=unused/undefined
Definition: pixfmt.h:264
U
#define U(x)
Definition: vpx_arith.h:37
AVCodecContext
main external API structure.
Definition: avcodec.h:439
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:72
Windows::Graphics::DirectX::Direct3D11::p
IDirect3DDxgiInterfaceAccess _COM_Outptr_ void ** p
Definition: vsrc_gfxcapture_winrt.hpp:53
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:200
ff_msrle_decode
int ff_msrle_decode(AVCodecContext *avctx, AVFrame *pic, int depth, GetByteContext *gb)
Decode stream in MS RLE format into frame.
Definition: msrledec.c:249
alpha
static const int16_t alpha[]
Definition: ilbcdata.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:565
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:600
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
AV_PIX_FMT_0RGB
@ AV_PIX_FMT_0RGB
packed RGB 8:8:8, 32bpp, XRGBXRGB... X=unused/undefined
Definition: pixfmt.h:262
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
width
#define width
Definition: dsp.h:89
src
#define src
Definition: vp8dsp.c:248
AV_PIX_FMT_RGB444
#define AV_PIX_FMT_RGB444
Definition: pixfmt.h:528
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