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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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 "internal.h"
25 #include "put_bits.h"
26 #include "pnm.h"
27 
28 
29 static int pnm_decode_frame(AVCodecContext *avctx, void *data,
30  int *got_frame, AVPacket *avpkt)
31 {
32  const uint8_t *buf = avpkt->data;
33  int buf_size = avpkt->size;
34  PNMContext * const s = avctx->priv_data;
35  AVFrame *picture = data;
36  AVFrame * const p = &s->picture;
37  int i, j, n, linesize, h, upgrade = 0;
38  unsigned char *ptr;
39  int components, sample_len;
40 
41  s->bytestream_start =
42  s->bytestream = buf;
43  s->bytestream_end = buf + buf_size;
44 
45  if (ff_pnm_decode_header(avctx, s) < 0)
46  return -1;
47 
48  if (p->data[0])
49  avctx->release_buffer(avctx, p);
50 
51  p->reference = 0;
52  if (ff_get_buffer(avctx, p) < 0) {
53  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
54  return -1;
55  }
57  p->key_frame = 1;
58 
59  switch (avctx->pix_fmt) {
60  default:
61  return -1;
62  case AV_PIX_FMT_RGB48BE:
63  n = avctx->width * 6;
64  components=3;
65  sample_len=16;
66  goto do_read;
67  case AV_PIX_FMT_RGB24:
68  n = avctx->width * 3;
69  components=3;
70  sample_len=8;
71  goto do_read;
72  case AV_PIX_FMT_GRAY8:
73  n = avctx->width;
74  components=1;
75  sample_len=8;
76  if (s->maxval < 255)
77  upgrade = 1;
78  goto do_read;
81  n = avctx->width * 2;
82  components=1;
83  sample_len=16;
84  if (s->maxval < 65535)
85  upgrade = 2;
86  goto do_read;
89  n = (avctx->width + 7) >> 3;
90  components=1;
91  sample_len=1;
92  do_read:
93  ptr = p->data[0];
94  linesize = p->linesize[0];
95  if (s->bytestream + n * avctx->height > s->bytestream_end)
96  return -1;
97  if(s->type < 4){
98  for (i=0; i<avctx->height; i++) {
99  PutBitContext pb;
100  init_put_bits(&pb, ptr, linesize);
101  for(j=0; j<avctx->width * components; j++){
102  unsigned int c=0;
103  int v=0;
104  while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))
105  s->bytestream++;
106  if(s->bytestream >= s->bytestream_end)
107  return -1;
108  do{
109  v= 10*v + c;
110  c= (*s->bytestream++) - '0';
111  }while(c <= 9);
112  put_bits(&pb, sample_len, (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval);
113  }
114  flush_put_bits(&pb);
115  ptr+= linesize;
116  }
117  }else{
118  for (i = 0; i < avctx->height; i++) {
119  if (!upgrade)
120  memcpy(ptr, s->bytestream, n);
121  else if (upgrade == 1) {
122  unsigned int j, f = (255 * 128 + s->maxval / 2) / s->maxval;
123  for (j = 0; j < n; j++)
124  ptr[j] = (s->bytestream[j] * f + 64) >> 7;
125  } else if (upgrade == 2) {
126  unsigned int j, v, f = (65535 * 32768 + s->maxval / 2) / s->maxval;
127  for (j = 0; j < n / 2; j++) {
128  v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
129  ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
130  }
131  }
132  s->bytestream += n;
133  ptr += linesize;
134  }
135  }
136  break;
137  case AV_PIX_FMT_YUV420P:
138  {
139  unsigned char *ptr1, *ptr2;
140 
141  n = avctx->width;
142  ptr = p->data[0];
143  linesize = p->linesize[0];
144  if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)
145  return -1;
146  for (i = 0; i < avctx->height; i++) {
147  memcpy(ptr, s->bytestream, n);
148  s->bytestream += n;
149  ptr += linesize;
150  }
151  ptr1 = p->data[1];
152  ptr2 = p->data[2];
153  n >>= 1;
154  h = avctx->height >> 1;
155  for (i = 0; i < h; i++) {
156  memcpy(ptr1, s->bytestream, n);
157  s->bytestream += n;
158  memcpy(ptr2, s->bytestream, n);
159  s->bytestream += n;
160  ptr1 += p->linesize[1];
161  ptr2 += p->linesize[2];
162  }
163  }
164  break;
165  case AV_PIX_FMT_RGB32:
166  ptr = p->data[0];
167  linesize = p->linesize[0];
168  if (s->bytestream + avctx->width * avctx->height * 4 > s->bytestream_end)
169  return -1;
170  for (i = 0; i < avctx->height; i++) {
171  int j, r, g, b, a;
172 
173  for (j = 0; j < avctx->width; j++) {
174  r = *s->bytestream++;
175  g = *s->bytestream++;
176  b = *s->bytestream++;
177  a = *s->bytestream++;
178  ((uint32_t *)ptr)[j] = (a << 24) | (r << 16) | (g << 8) | b;
179  }
180  ptr += linesize;
181  }
182  break;
183  }
184  *picture = s->picture;
185  *got_frame = 1;
186 
187  return s->bytestream - s->bytestream_start;
188 }
189 
190 
191 #if CONFIG_PGM_DECODER
192 AVCodec ff_pgm_decoder = {
193  .name = "pgm",
194  .type = AVMEDIA_TYPE_VIDEO,
195  .id = AV_CODEC_ID_PGM,
196  .priv_data_size = sizeof(PNMContext),
197  .init = ff_pnm_init,
198  .close = ff_pnm_end,
200  .capabilities = CODEC_CAP_DR1,
201  .long_name = NULL_IF_CONFIG_SMALL("PGM (Portable GrayMap) image"),
202 };
203 #endif
204 
205 #if CONFIG_PGMYUV_DECODER
206 AVCodec ff_pgmyuv_decoder = {
207  .name = "pgmyuv",
208  .type = AVMEDIA_TYPE_VIDEO,
209  .id = AV_CODEC_ID_PGMYUV,
210  .priv_data_size = sizeof(PNMContext),
211  .init = ff_pnm_init,
212  .close = ff_pnm_end,
214  .capabilities = CODEC_CAP_DR1,
215  .long_name = NULL_IF_CONFIG_SMALL("PGMYUV (Portable GrayMap YUV) image"),
216 };
217 #endif
218 
219 #if CONFIG_PPM_DECODER
220 AVCodec ff_ppm_decoder = {
221  .name = "ppm",
222  .type = AVMEDIA_TYPE_VIDEO,
223  .id = AV_CODEC_ID_PPM,
224  .priv_data_size = sizeof(PNMContext),
225  .init = ff_pnm_init,
226  .close = ff_pnm_end,
228  .capabilities = CODEC_CAP_DR1,
229  .long_name = NULL_IF_CONFIG_SMALL("PPM (Portable PixelMap) image"),
230 };
231 #endif
232 
233 #if CONFIG_PBM_DECODER
234 AVCodec ff_pbm_decoder = {
235  .name = "pbm",
236  .type = AVMEDIA_TYPE_VIDEO,
237  .id = AV_CODEC_ID_PBM,
238  .priv_data_size = sizeof(PNMContext),
239  .init = ff_pnm_init,
240  .close = ff_pnm_end,
242  .capabilities = CODEC_CAP_DR1,
243  .long_name = NULL_IF_CONFIG_SMALL("PBM (Portable BitMap) image"),
244 };
245 #endif
246 
247 #if CONFIG_PAM_DECODER
248 AVCodec ff_pam_decoder = {
249  .name = "pam",
250  .type = AVMEDIA_TYPE_VIDEO,
251  .id = AV_CODEC_ID_PAM,
252  .priv_data_size = sizeof(PNMContext),
253  .init = ff_pnm_init,
254  .close = ff_pnm_end,
256  .capabilities = CODEC_CAP_DR1,
257  .long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),
258 };
259 #endif