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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, 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;
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;
113  n = (avctx->width + 7) >> 3;
114  components=1;
115  sample_len=1;
116  is_mono = 1;
117  do_read:
118  ptr = p->data[0];
119  linesize = p->linesize[0];
120  if (s->bytestream + n * avctx->height > s->bytestream_end)
121  return AVERROR_INVALIDDATA;
122  if(s->type < 4 || (is_mono && s->type==7)){
123  for (i=0; i<avctx->height; i++) {
124  PutBitContext pb;
125  init_put_bits(&pb, ptr, linesize);
126  for(j=0; j<avctx->width * components; j++){
127  unsigned int c=0;
128  int v=0;
129  if(s->type < 4)
130  while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))
131  s->bytestream++;
132  if(s->bytestream >= s->bytestream_end)
133  return AVERROR_INVALIDDATA;
134  if (is_mono) {
135  /* read a single digit */
136  v = (*s->bytestream++)&1;
137  } else {
138  /* read a sequence of digits */
139  do {
140  v = 10*v + c;
141  c = (*s->bytestream++) - '0';
142  } while (c <= 9);
143  }
144  if (sample_len == 16) {
145  ((uint16_t*)ptr)[j] = (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval;
146  } else
147  put_bits(&pb, sample_len, (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval);
148  }
149  if (sample_len != 16)
150  flush_put_bits(&pb);
151  ptr+= linesize;
152  }
153  }else{
154  for (i = 0; i < avctx->height; i++) {
155  if (!upgrade)
156  samplecpy(ptr, s->bytestream, n, s->maxval);
157  else if (upgrade == 1) {
158  unsigned int j, f = (255 * 128 + s->maxval / 2) / s->maxval;
159  for (j = 0; j < n; j++)
160  ptr[j] = (s->bytestream[j] * f + 64) >> 7;
161  } else if (upgrade == 2) {
162  unsigned int j, v, f = (65535 * 32768 + s->maxval / 2) / s->maxval;
163  for (j = 0; j < n / 2; j++) {
164  v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
165  ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
166  }
167  }
168  s->bytestream += n;
169  ptr += linesize;
170  }
171  }
172  break;
173  case AV_PIX_FMT_YUV420P:
174  case AV_PIX_FMT_YUV420P9:
176  {
177  unsigned char *ptr1, *ptr2;
178 
179  n = avctx->width;
180  ptr = p->data[0];
181  linesize = p->linesize[0];
182  if (s->maxval >= 256)
183  n *= 2;
184  if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)
185  return AVERROR_INVALIDDATA;
186  for (i = 0; i < avctx->height; i++) {
187  samplecpy(ptr, s->bytestream, n, s->maxval);
188  s->bytestream += n;
189  ptr += linesize;
190  }
191  ptr1 = p->data[1];
192  ptr2 = p->data[2];
193  n >>= 1;
194  h = avctx->height >> 1;
195  for (i = 0; i < h; i++) {
196  samplecpy(ptr1, s->bytestream, n, s->maxval);
197  s->bytestream += n;
198  samplecpy(ptr2, s->bytestream, n, s->maxval);
199  s->bytestream += n;
200  ptr1 += p->linesize[1];
201  ptr2 += p->linesize[2];
202  }
203  }
204  break;
206  {
207  uint16_t *ptr1, *ptr2;
208  const int f = (65535 * 32768 + s->maxval / 2) / s->maxval;
209  unsigned int j, v;
210 
211  n = avctx->width * 2;
212  ptr = p->data[0];
213  linesize = p->linesize[0];
214  if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)
215  return AVERROR_INVALIDDATA;
216  for (i = 0; i < avctx->height; i++) {
217  for (j = 0; j < n / 2; j++) {
218  v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
219  ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
220  }
221  s->bytestream += n;
222  ptr += linesize;
223  }
224  ptr1 = (uint16_t*)p->data[1];
225  ptr2 = (uint16_t*)p->data[2];
226  n >>= 1;
227  h = avctx->height >> 1;
228  for (i = 0; i < h; i++) {
229  for (j = 0; j < n / 2; j++) {
230  v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
231  ptr1[j] = (v * f + 16384) >> 15;
232  }
233  s->bytestream += n;
234 
235  for (j = 0; j < n / 2; j++) {
236  v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
237  ptr2[j] = (v * f + 16384) >> 15;
238  }
239  s->bytestream += n;
240 
241  ptr1 += p->linesize[1] / 2;
242  ptr2 += p->linesize[2] / 2;
243  }
244  }
245  break;
246  }
247  *got_frame = 1;
248 
249  return s->bytestream - s->bytestream_start;
250 }
251 
252 
253 #if CONFIG_PGM_DECODER
254 AVCodec ff_pgm_decoder = {
255  .name = "pgm",
256  .long_name = NULL_IF_CONFIG_SMALL("PGM (Portable GrayMap) image"),
257  .type = AVMEDIA_TYPE_VIDEO,
258  .id = AV_CODEC_ID_PGM,
259  .priv_data_size = sizeof(PNMContext),
261  .capabilities = CODEC_CAP_DR1,
262 };
263 #endif
264 
265 #if CONFIG_PGMYUV_DECODER
266 AVCodec ff_pgmyuv_decoder = {
267  .name = "pgmyuv",
268  .long_name = NULL_IF_CONFIG_SMALL("PGMYUV (Portable GrayMap YUV) image"),
269  .type = AVMEDIA_TYPE_VIDEO,
270  .id = AV_CODEC_ID_PGMYUV,
271  .priv_data_size = sizeof(PNMContext),
273  .capabilities = CODEC_CAP_DR1,
274 };
275 #endif
276 
277 #if CONFIG_PPM_DECODER
278 AVCodec ff_ppm_decoder = {
279  .name = "ppm",
280  .long_name = NULL_IF_CONFIG_SMALL("PPM (Portable PixelMap) image"),
281  .type = AVMEDIA_TYPE_VIDEO,
282  .id = AV_CODEC_ID_PPM,
283  .priv_data_size = sizeof(PNMContext),
285  .capabilities = CODEC_CAP_DR1,
286 };
287 #endif
288 
289 #if CONFIG_PBM_DECODER
290 AVCodec ff_pbm_decoder = {
291  .name = "pbm",
292  .long_name = NULL_IF_CONFIG_SMALL("PBM (Portable BitMap) image"),
293  .type = AVMEDIA_TYPE_VIDEO,
294  .id = AV_CODEC_ID_PBM,
295  .priv_data_size = sizeof(PNMContext),
297  .capabilities = CODEC_CAP_DR1,
298 };
299 #endif
300 
301 #if CONFIG_PAM_DECODER
302 AVCodec ff_pam_decoder = {
303  .name = "pam",
304  .long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),
305  .type = AVMEDIA_TYPE_VIDEO,
306  .id = AV_CODEC_ID_PAM,
307  .priv_data_size = sizeof(PNMContext),
309  .capabilities = CODEC_CAP_DR1,
310 };
311 #endif