FFmpeg
pnmdec.c
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1 /*
2  * PNM image format
3  * Copyright (c) 2002, 2003 Fabrice Bellard
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 "internal.h"
24 #include "put_bits.h"
25 #include "pnm.h"
26 
27 static void samplecpy(uint8_t *dst, const uint8_t *src, int n, int maxval)
28 {
29  if (maxval <= 255) {
30  memcpy(dst, src, n);
31  } else {
32  int i;
33  for (i=0; i<n/2; i++) {
34  ((uint16_t *)dst)[i] = AV_RB16(src+2*i);
35  }
36  }
37 }
38 
39 static int pnm_decode_frame(AVCodecContext *avctx, void *data,
40  int *got_frame, AVPacket *avpkt)
41 {
42  const uint8_t *buf = avpkt->data;
43  int buf_size = avpkt->size;
44  PNMContext * const s = avctx->priv_data;
45  AVFrame * const p = data;
46  int i, j, k, n, linesize, h, upgrade = 0, is_mono = 0;
47  unsigned char *ptr;
48  int components, sample_len, ret;
49 
50  s->bytestream_start =
51  s->bytestream = (uint8_t *)buf;
52  s->bytestream_end = (uint8_t *)buf + buf_size;
53 
54  if ((ret = ff_pnm_decode_header(avctx, s)) < 0)
55  return ret;
56 
57  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
58  return ret;
59  p->pict_type = AV_PICTURE_TYPE_I;
60  p->key_frame = 1;
61  avctx->bits_per_raw_sample = av_log2(s->maxval) + 1;
62 
63  switch (avctx->pix_fmt) {
64  default:
65  return AVERROR(EINVAL);
66  case AV_PIX_FMT_RGBA64:
67  n = avctx->width * 8;
68  components=4;
69  sample_len=16;
70  if (s->maxval < 65535)
71  upgrade = 2;
72  goto do_read;
73  case AV_PIX_FMT_RGB48:
74  n = avctx->width * 6;
75  components=3;
76  sample_len=16;
77  if (s->maxval < 65535)
78  upgrade = 2;
79  goto do_read;
80  case AV_PIX_FMT_RGBA:
81  n = avctx->width * 4;
82  components=4;
83  sample_len=8;
84  goto do_read;
85  case AV_PIX_FMT_RGB24:
86  n = avctx->width * 3;
87  components=3;
88  sample_len=8;
89  if (s->maxval < 255)
90  upgrade = 1;
91  goto do_read;
92  case AV_PIX_FMT_GRAY8:
93  n = avctx->width;
94  components=1;
95  sample_len=8;
96  if (s->maxval < 255)
97  upgrade = 1;
98  goto do_read;
99  case AV_PIX_FMT_GRAY8A:
100  n = avctx->width * 2;
101  components=2;
102  sample_len=8;
103  goto do_read;
104  case AV_PIX_FMT_GRAY16:
105  n = avctx->width * 2;
106  components=1;
107  sample_len=16;
108  if (s->maxval < 65535)
109  upgrade = 2;
110  goto do_read;
111  case AV_PIX_FMT_YA16:
112  n = avctx->width * 4;
113  components=2;
114  sample_len=16;
115  if (s->maxval < 65535)
116  upgrade = 2;
117  goto do_read;
118  case AV_PIX_FMT_MONOWHITE:
119  case AV_PIX_FMT_MONOBLACK:
120  n = (avctx->width + 7) >> 3;
121  components=1;
122  sample_len=1;
123  is_mono = 1;
124  do_read:
125  ptr = p->data[0];
126  linesize = p->linesize[0];
127  if (n * avctx->height > s->bytestream_end - s->bytestream)
128  return AVERROR_INVALIDDATA;
129  if(s->type < 4 || (is_mono && s->type==7)){
130  for (i=0; i<avctx->height; i++) {
131  PutBitContext pb;
132  init_put_bits(&pb, ptr, linesize);
133  for(j=0; j<avctx->width * components; j++){
134  unsigned int c=0;
135  unsigned v=0;
136  if(s->type < 4)
137  while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))
138  s->bytestream++;
139  if(s->bytestream >= s->bytestream_end)
140  return AVERROR_INVALIDDATA;
141  if (is_mono) {
142  /* read a single digit */
143  v = (*s->bytestream++)&1;
144  } else {
145  /* read a sequence of digits */
146  for (k = 0; k < 5 && c <= 9; k += 1) {
147  v = 10*v + c;
148  c = (*s->bytestream++) - '0';
149  }
150  if (v > s->maxval) {
151  av_log(avctx, AV_LOG_ERROR, "value %d larger than maxval %d\n", v, s->maxval);
152  return AVERROR_INVALIDDATA;
153  }
154  }
155  if (sample_len == 16) {
156  ((uint16_t*)ptr)[j] = (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval;
157  } else
158  put_bits(&pb, sample_len, (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval);
159  }
160  if (sample_len != 16)
161  flush_put_bits(&pb);
162  ptr+= linesize;
163  }
164  }else{
165  for (i = 0; i < avctx->height; i++) {
166  if (!upgrade)
167  samplecpy(ptr, s->bytestream, n, s->maxval);
168  else if (upgrade == 1) {
169  unsigned int j, f = (255 * 128 + s->maxval / 2) / s->maxval;
170  for (j = 0; j < n; j++)
171  ptr[j] = (s->bytestream[j] * f + 64) >> 7;
172  } else if (upgrade == 2) {
173  unsigned int j, v, f = (65535 * 32768 + s->maxval / 2) / s->maxval;
174  for (j = 0; j < n / 2; j++) {
175  v = AV_RB16(s->bytestream + 2*j);
176  ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
177  }
178  }
179  s->bytestream += n;
180  ptr += linesize;
181  }
182  }
183  break;
184  case AV_PIX_FMT_YUV420P:
185  case AV_PIX_FMT_YUV420P9:
186  case AV_PIX_FMT_YUV420P10:
187  {
188  unsigned char *ptr1, *ptr2;
189 
190  n = avctx->width;
191  ptr = p->data[0];
192  linesize = p->linesize[0];
193  if (s->maxval >= 256)
194  n *= 2;
195  if (n * avctx->height * 3 / 2 > s->bytestream_end - s->bytestream)
196  return AVERROR_INVALIDDATA;
197  for (i = 0; i < avctx->height; i++) {
198  samplecpy(ptr, s->bytestream, n, s->maxval);
199  s->bytestream += n;
200  ptr += linesize;
201  }
202  ptr1 = p->data[1];
203  ptr2 = p->data[2];
204  n >>= 1;
205  h = avctx->height >> 1;
206  for (i = 0; i < h; i++) {
207  samplecpy(ptr1, s->bytestream, n, s->maxval);
208  s->bytestream += n;
209  samplecpy(ptr2, s->bytestream, n, s->maxval);
210  s->bytestream += n;
211  ptr1 += p->linesize[1];
212  ptr2 += p->linesize[2];
213  }
214  }
215  break;
216  case AV_PIX_FMT_YUV420P16:
217  {
218  uint16_t *ptr1, *ptr2;
219  const int f = (65535 * 32768 + s->maxval / 2) / s->maxval;
220  unsigned int j, v;
221 
222  n = avctx->width * 2;
223  ptr = p->data[0];
224  linesize = p->linesize[0];
225  if (n * avctx->height * 3 / 2 > s->bytestream_end - s->bytestream)
226  return AVERROR_INVALIDDATA;
227  for (i = 0; i < avctx->height; i++) {
228  for (j = 0; j < n / 2; j++) {
229  v = AV_RB16(s->bytestream + 2*j);
230  ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
231  }
232  s->bytestream += n;
233  ptr += linesize;
234  }
235  ptr1 = (uint16_t*)p->data[1];
236  ptr2 = (uint16_t*)p->data[2];
237  n >>= 1;
238  h = avctx->height >> 1;
239  for (i = 0; i < h; i++) {
240  for (j = 0; j < n / 2; j++) {
241  v = AV_RB16(s->bytestream + 2*j);
242  ptr1[j] = (v * f + 16384) >> 15;
243  }
244  s->bytestream += n;
245 
246  for (j = 0; j < n / 2; j++) {
247  v = AV_RB16(s->bytestream + 2*j);
248  ptr2[j] = (v * f + 16384) >> 15;
249  }
250  s->bytestream += n;
251 
252  ptr1 += p->linesize[1] / 2;
253  ptr2 += p->linesize[2] / 2;
254  }
255  }
256  break;
257  }
258  *got_frame = 1;
259 
260  return s->bytestream - s->bytestream_start;
261 }
262 
263 
264 #if CONFIG_PGM_DECODER
265 AVCodec ff_pgm_decoder = {
266  .name = "pgm",
267  .long_name = NULL_IF_CONFIG_SMALL("PGM (Portable GrayMap) image"),
268  .type = AVMEDIA_TYPE_VIDEO,
269  .id = AV_CODEC_ID_PGM,
270  .priv_data_size = sizeof(PNMContext),
271  .decode = pnm_decode_frame,
272  .capabilities = AV_CODEC_CAP_DR1,
273 };
274 #endif
275 
276 #if CONFIG_PGMYUV_DECODER
277 AVCodec ff_pgmyuv_decoder = {
278  .name = "pgmyuv",
279  .long_name = NULL_IF_CONFIG_SMALL("PGMYUV (Portable GrayMap YUV) image"),
280  .type = AVMEDIA_TYPE_VIDEO,
281  .id = AV_CODEC_ID_PGMYUV,
282  .priv_data_size = sizeof(PNMContext),
283  .decode = pnm_decode_frame,
284  .capabilities = AV_CODEC_CAP_DR1,
285 };
286 #endif
287 
288 #if CONFIG_PPM_DECODER
289 AVCodec ff_ppm_decoder = {
290  .name = "ppm",
291  .long_name = NULL_IF_CONFIG_SMALL("PPM (Portable PixelMap) image"),
292  .type = AVMEDIA_TYPE_VIDEO,
293  .id = AV_CODEC_ID_PPM,
294  .priv_data_size = sizeof(PNMContext),
295  .decode = pnm_decode_frame,
296  .capabilities = AV_CODEC_CAP_DR1,
297 };
298 #endif
299 
300 #if CONFIG_PBM_DECODER
301 AVCodec ff_pbm_decoder = {
302  .name = "pbm",
303  .long_name = NULL_IF_CONFIG_SMALL("PBM (Portable BitMap) image"),
304  .type = AVMEDIA_TYPE_VIDEO,
305  .id = AV_CODEC_ID_PBM,
306  .priv_data_size = sizeof(PNMContext),
307  .decode = pnm_decode_frame,
308  .capabilities = AV_CODEC_CAP_DR1,
309 };
310 #endif
311 
312 #if CONFIG_PAM_DECODER
313 AVCodec ff_pam_decoder = {
314  .name = "pam",
315  .long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),
316  .type = AVMEDIA_TYPE_VIDEO,
317  .id = AV_CODEC_ID_PAM,
318  .priv_data_size = sizeof(PNMContext),
319  .decode = pnm_decode_frame,
320  .capabilities = AV_CODEC_CAP_DR1,
321 };
322 #endif
AVCodec
AVCodec.
Definition: avcodec.h:3481
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
AV_CODEC_ID_PBM
@ AV_CODEC_ID_PBM
Definition: avcodec.h:281
n
int n
Definition: avisynth_c.h:760
init_put_bits
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:48
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:208
internal.h
AVPacket::data
uint8_t * data
Definition: avcodec.h:1477
AV_CODEC_ID_PPM
@ AV_CODEC_ID_PPM
Definition: avcodec.h:280
AV_CODEC_ID_PGM
@ AV_CODEC_ID_PGM
Definition: avcodec.h:282
data
const char data[16]
Definition: mxf.c:91
AV_PIX_FMT_MONOWHITE
@ AV_PIX_FMT_MONOWHITE
Y , 1bpp, 0 is white, 1 is black, in each byte pixels are ordered from the msb to the lsb.
Definition: pixfmt.h:75
AV_PIX_FMT_YUV420P10
#define AV_PIX_FMT_YUV420P10
Definition: pixfmt.h:387
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
AVFrame::key_frame
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
AV_PIX_FMT_GRAY16
#define AV_PIX_FMT_GRAY16
Definition: pixfmt.h:371
src
#define src
Definition: vp8dsp.c:254
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
buf
void * buf
Definition: avisynth_c.h:766
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:2796
AV_PIX_FMT_YUV420P9
#define AV_PIX_FMT_YUV420P9
Definition: pixfmt.h:384
AV_PIX_FMT_YUV420P16
#define AV_PIX_FMT_YUV420P16
Definition: pixfmt.h:398
ff_pgm_decoder
AVCodec ff_pgm_decoder
AV_PIX_FMT_YUV420P
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
f
#define f(width, name)
Definition: cbs_vp9.c:255
PutBitContext
Definition: put_bits.h:35
AV_PIX_FMT_RGBA
@ AV_PIX_FMT_RGBA
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:93
if
if(ret)
Definition: filter_design.txt:179
AV_PIX_FMT_GRAY8A
@ AV_PIX_FMT_GRAY8A
alias for AV_PIX_FMT_YA8
Definition: pixfmt.h:146
AV_PIX_FMT_RGBA64
#define AV_PIX_FMT_RGBA64
Definition: pixfmt.h:377
AV_PIX_FMT_MONOBLACK
@ AV_PIX_FMT_MONOBLACK
Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb.
Definition: pixfmt.h:76
AV_CODEC_ID_PGMYUV
@ AV_CODEC_ID_PGMYUV
Definition: avcodec.h:283
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
samplecpy
static void samplecpy(uint8_t *dst, const uint8_t *src, int n, int maxval)
Definition: pnmdec.c:27
AV_PIX_FMT_GRAY8
@ AV_PIX_FMT_GRAY8
Y , 8bpp.
Definition: pixfmt.h:74
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
pnm.h
AV_CODEC_ID_PAM
@ AV_CODEC_ID_PAM
Definition: avcodec.h:284
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1965
AV_PIX_FMT_RGB24
@ AV_PIX_FMT_RGB24
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:68
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981
AVPacket::size
int size
Definition: avcodec.h:1478
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:188
AV_PIX_FMT_RGB48
#define AV_PIX_FMT_RGB48
Definition: pixfmt.h:373
PNMContext
Definition: pnm.h:27
ff_pgmyuv_decoder
AVCodec ff_pgmyuv_decoder
ff_pbm_decoder
AVCodec ff_pbm_decoder
AV_PIX_FMT_YA16
#define AV_PIX_FMT_YA16
Definition: pixfmt.h:372
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
uint8_t
uint8_t
Definition: audio_convert.c:194
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3488
AVCodecContext::height
int height
Definition: avcodec.h:1738
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVCodecContext
main external API structure.
Definition: avcodec.h:1565
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
ff_pnm_decode_header
int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext *const s)
Definition: pnm.c:65
flush_put_bits
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:101
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:1592
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1454
ff_pam_decoder
AVCodec ff_pam_decoder
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:1738
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
h
h
Definition: vp9dsp_template.c:2038
pnm_decode_frame
static int pnm_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: pnmdec.c:39
put_bits.h
av_log2
int av_log2(unsigned v)
Definition: intmath.c:26
ff_ppm_decoder
AVCodec ff_ppm_decoder
AV_RB16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:94
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