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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 
28 static int pnm_decode_frame(AVCodecContext *avctx, void *data,
29  int *got_frame, AVPacket *avpkt)
30 {
31  const uint8_t *buf = avpkt->data;
32  int buf_size = avpkt->size;
33  PNMContext * const s = avctx->priv_data;
34  AVFrame *picture = data;
35  AVFrame * const p = &s->picture;
36  int i, j, n, linesize, h, upgrade = 0, is_mono = 0;
37  unsigned char *ptr;
38  int components, sample_len, ret;
39 
40  s->bytestream_start =
41  s->bytestream = (uint8_t *)buf;
42  s->bytestream_end = (uint8_t *)buf + buf_size;
43 
44  if (ff_pnm_decode_header(avctx, s) < 0)
45  return AVERROR_INVALIDDATA;
46 
47  if (p->data[0])
48  avctx->release_buffer(avctx, p);
49 
50  p->reference = 0;
51  if ((ret = ff_get_buffer(avctx, p)) < 0) {
52  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
53  return ret;
54  }
56  p->key_frame = 1;
57 
58  switch (avctx->pix_fmt) {
59  default:
60  return AVERROR_INVALIDDATA;
62  n = avctx->width * 8;
63  components=4;
64  sample_len=16;
65  goto do_read;
66  case AV_PIX_FMT_RGB48BE:
67  n = avctx->width * 6;
68  components=3;
69  sample_len=16;
70  goto do_read;
71  case AV_PIX_FMT_RGBA:
72  n = avctx->width * 4;
73  components=4;
74  sample_len=8;
75  goto do_read;
76  case AV_PIX_FMT_RGB24:
77  n = avctx->width * 3;
78  components=3;
79  sample_len=8;
80  goto do_read;
81  case AV_PIX_FMT_GRAY8:
82  n = avctx->width;
83  components=1;
84  sample_len=8;
85  if (s->maxval < 255)
86  upgrade = 1;
87  goto do_read;
88  case AV_PIX_FMT_GRAY8A:
89  n = avctx->width * 2;
90  components=2;
91  sample_len=8;
92  goto do_read;
95  n = avctx->width * 2;
96  components=1;
97  sample_len=16;
98  if (s->maxval < 65535)
99  upgrade = 2;
100  goto do_read;
103  n = (avctx->width + 7) >> 3;
104  components=1;
105  sample_len=1;
106  is_mono = 1;
107  do_read:
108  ptr = p->data[0];
109  linesize = p->linesize[0];
110  if (s->bytestream + n * avctx->height > s->bytestream_end)
111  return AVERROR_INVALIDDATA;
112  if(s->type < 4 || (is_mono && s->type==7)){
113  for (i=0; i<avctx->height; i++) {
114  PutBitContext pb;
115  init_put_bits(&pb, ptr, linesize);
116  for(j=0; j<avctx->width * components; j++){
117  unsigned int c=0;
118  int v=0;
119  if(s->type < 4)
120  while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))
121  s->bytestream++;
122  if(s->bytestream >= s->bytestream_end)
123  return AVERROR_INVALIDDATA;
124  if (is_mono) {
125  /* read a single digit */
126  v = (*s->bytestream++)&1;
127  } else {
128  /* read a sequence of digits */
129  do {
130  v = 10*v + c;
131  c = (*s->bytestream++) - '0';
132  } while (c <= 9);
133  }
134  put_bits(&pb, sample_len, (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval);
135  }
136  flush_put_bits(&pb);
137  ptr+= linesize;
138  }
139  }else{
140  for (i = 0; i < avctx->height; i++) {
141  if (!upgrade)
142  memcpy(ptr, s->bytestream, n);
143  else if (upgrade == 1) {
144  unsigned int j, f = (255 * 128 + s->maxval / 2) / s->maxval;
145  for (j = 0; j < n; j++)
146  ptr[j] = (s->bytestream[j] * f + 64) >> 7;
147  } else if (upgrade == 2) {
148  unsigned int j, v, f = (65535 * 32768 + s->maxval / 2) / s->maxval;
149  for (j = 0; j < n / 2; j++) {
150  v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
151  ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
152  }
153  }
154  s->bytestream += n;
155  ptr += linesize;
156  }
157  }
158  break;
159  case AV_PIX_FMT_YUV420P:
160  {
161  unsigned char *ptr1, *ptr2;
162 
163  n = avctx->width;
164  ptr = p->data[0];
165  linesize = p->linesize[0];
166  if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)
167  return AVERROR_INVALIDDATA;
168  for (i = 0; i < avctx->height; i++) {
169  memcpy(ptr, s->bytestream, n);
170  s->bytestream += n;
171  ptr += linesize;
172  }
173  ptr1 = p->data[1];
174  ptr2 = p->data[2];
175  n >>= 1;
176  h = avctx->height >> 1;
177  for (i = 0; i < h; i++) {
178  memcpy(ptr1, s->bytestream, n);
179  s->bytestream += n;
180  memcpy(ptr2, s->bytestream, n);
181  s->bytestream += n;
182  ptr1 += p->linesize[1];
183  ptr2 += p->linesize[2];
184  }
185  }
186  break;
187  }
188  *picture = s->picture;
189  *got_frame = 1;
190 
191  return s->bytestream - s->bytestream_start;
192 }
193 
194 
195 #if CONFIG_PGM_DECODER
196 AVCodec ff_pgm_decoder = {
197  .name = "pgm",
198  .type = AVMEDIA_TYPE_VIDEO,
199  .id = AV_CODEC_ID_PGM,
200  .priv_data_size = sizeof(PNMContext),
201  .init = ff_pnm_init,
202  .close = ff_pnm_end,
204  .capabilities = CODEC_CAP_DR1,
205  .long_name = NULL_IF_CONFIG_SMALL("PGM (Portable GrayMap) image"),
206 };
207 #endif
208 
209 #if CONFIG_PGMYUV_DECODER
210 AVCodec ff_pgmyuv_decoder = {
211  .name = "pgmyuv",
212  .type = AVMEDIA_TYPE_VIDEO,
213  .id = AV_CODEC_ID_PGMYUV,
214  .priv_data_size = sizeof(PNMContext),
215  .init = ff_pnm_init,
216  .close = ff_pnm_end,
218  .capabilities = CODEC_CAP_DR1,
219  .long_name = NULL_IF_CONFIG_SMALL("PGMYUV (Portable GrayMap YUV) image"),
220 };
221 #endif
222 
223 #if CONFIG_PPM_DECODER
224 AVCodec ff_ppm_decoder = {
225  .name = "ppm",
226  .type = AVMEDIA_TYPE_VIDEO,
227  .id = AV_CODEC_ID_PPM,
228  .priv_data_size = sizeof(PNMContext),
229  .init = ff_pnm_init,
230  .close = ff_pnm_end,
232  .capabilities = CODEC_CAP_DR1,
233  .long_name = NULL_IF_CONFIG_SMALL("PPM (Portable PixelMap) image"),
234 };
235 #endif
236 
237 #if CONFIG_PBM_DECODER
238 AVCodec ff_pbm_decoder = {
239  .name = "pbm",
240  .type = AVMEDIA_TYPE_VIDEO,
241  .id = AV_CODEC_ID_PBM,
242  .priv_data_size = sizeof(PNMContext),
243  .init = ff_pnm_init,
244  .close = ff_pnm_end,
246  .capabilities = CODEC_CAP_DR1,
247  .long_name = NULL_IF_CONFIG_SMALL("PBM (Portable BitMap) image"),
248 };
249 #endif
250 
251 #if CONFIG_PAM_DECODER
252 AVCodec ff_pam_decoder = {
253  .name = "pam",
254  .type = AVMEDIA_TYPE_VIDEO,
255  .id = AV_CODEC_ID_PAM,
256  .priv_data_size = sizeof(PNMContext),
257  .init = ff_pnm_init,
258  .close = ff_pnm_end,
260  .capabilities = CODEC_CAP_DR1,
261  .long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),
262 };
263 #endif