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 "put_bits.h"
25 #include "pnm.h"
26 
27 
28 static int pnm_decode_frame(AVCodecContext *avctx, void *data,
29  int *data_size, 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 = (AVFrame*)&s->picture;
36  int i, j, n, linesize, h, upgrade = 0;
37  unsigned char *ptr;
38  int components, sample_len;
39 
40  s->bytestream_start =
41  s->bytestream = buf;
42  s->bytestream_end = buf + buf_size;
43 
44  if (ff_pnm_decode_header(avctx, s) < 0)
45  return -1;
46 
47  if (p->data[0])
48  avctx->release_buffer(avctx, p);
49 
50  p->reference = 0;
51  if (avctx->get_buffer(avctx, p) < 0) {
52  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
53  return -1;
54  }
56  p->key_frame = 1;
57 
58  switch (avctx->pix_fmt) {
59  default:
60  return -1;
61  case PIX_FMT_RGB48BE:
62  n = avctx->width * 6;
63  components=3;
64  sample_len=16;
65  goto do_read;
66  case PIX_FMT_RGB24:
67  n = avctx->width * 3;
68  components=3;
69  sample_len=8;
70  goto do_read;
71  case PIX_FMT_GRAY8:
72  n = avctx->width;
73  components=1;
74  sample_len=8;
75  if (s->maxval < 255)
76  upgrade = 1;
77  goto do_read;
78  case PIX_FMT_GRAY16BE:
79  case PIX_FMT_GRAY16LE:
80  n = avctx->width * 2;
81  components=1;
82  sample_len=16;
83  if (s->maxval < 65535)
84  upgrade = 2;
85  goto do_read;
86  case PIX_FMT_MONOWHITE:
87  case PIX_FMT_MONOBLACK:
88  n = (avctx->width + 7) >> 3;
89  components=1;
90  sample_len=1;
91  do_read:
92  ptr = p->data[0];
93  linesize = p->linesize[0];
94  if (s->bytestream + n * avctx->height > s->bytestream_end)
95  return -1;
96  if(s->type < 4){
97  for (i=0; i<avctx->height; i++) {
98  PutBitContext pb;
99  init_put_bits(&pb, ptr, linesize);
100  for(j=0; j<avctx->width * components; j++){
101  unsigned int c=0;
102  int v=0;
103  while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))
104  s->bytestream++;
105  if(s->bytestream >= s->bytestream_end)
106  return -1;
107  do{
108  v= 10*v + c;
109  c= (*s->bytestream++) - '0';
110  }while(c <= 9);
111  put_bits(&pb, sample_len, (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval);
112  }
113  flush_put_bits(&pb);
114  ptr+= linesize;
115  }
116  }else{
117  for (i = 0; i < avctx->height; i++) {
118  if (!upgrade)
119  memcpy(ptr, s->bytestream, n);
120  else if (upgrade == 1) {
121  unsigned int j, f = (255 * 128 + s->maxval / 2) / s->maxval;
122  for (j = 0; j < n; j++)
123  ptr[j] = (s->bytestream[j] * f + 64) >> 7;
124  } else if (upgrade == 2) {
125  unsigned int j, v, f = (65535 * 32768 + s->maxval / 2) / s->maxval;
126  for (j = 0; j < n / 2; j++) {
127  v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
128  ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
129  }
130  }
131  s->bytestream += n;
132  ptr += linesize;
133  }
134  }
135  break;
136  case PIX_FMT_YUV420P:
137  {
138  unsigned char *ptr1, *ptr2;
139 
140  n = avctx->width;
141  ptr = p->data[0];
142  linesize = p->linesize[0];
143  if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)
144  return -1;
145  for (i = 0; i < avctx->height; i++) {
146  memcpy(ptr, s->bytestream, n);
147  s->bytestream += n;
148  ptr += linesize;
149  }
150  ptr1 = p->data[1];
151  ptr2 = p->data[2];
152  n >>= 1;
153  h = avctx->height >> 1;
154  for (i = 0; i < h; i++) {
155  memcpy(ptr1, s->bytestream, n);
156  s->bytestream += n;
157  memcpy(ptr2, s->bytestream, n);
158  s->bytestream += n;
159  ptr1 += p->linesize[1];
160  ptr2 += p->linesize[2];
161  }
162  }
163  break;
164  case PIX_FMT_RGB32:
165  ptr = p->data[0];
166  linesize = p->linesize[0];
167  if (s->bytestream + avctx->width * avctx->height * 4 > s->bytestream_end)
168  return -1;
169  for (i = 0; i < avctx->height; i++) {
170  int j, r, g, b, a;
171 
172  for (j = 0; j < avctx->width; j++) {
173  r = *s->bytestream++;
174  g = *s->bytestream++;
175  b = *s->bytestream++;
176  a = *s->bytestream++;
177  ((uint32_t *)ptr)[j] = (a << 24) | (r << 16) | (g << 8) | b;
178  }
179  ptr += linesize;
180  }
181  break;
182  }
183  *picture = *(AVFrame*)&s->picture;
184  *data_size = sizeof(AVPicture);
185 
186  return s->bytestream - s->bytestream_start;
187 }
188 
189 
190 #if CONFIG_PGM_DECODER
191 AVCodec ff_pgm_decoder = {
192  .name = "pgm",
193  .type = AVMEDIA_TYPE_VIDEO,
194  .id = CODEC_ID_PGM,
195  .priv_data_size = sizeof(PNMContext),
196  .init = ff_pnm_init,
197  .close = ff_pnm_end,
199  .capabilities = CODEC_CAP_DR1,
200  .pix_fmts = (const enum PixelFormat[]){PIX_FMT_GRAY8, PIX_FMT_GRAY16BE, PIX_FMT_NONE},
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 = 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  .pix_fmts = (const enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_NONE},
216  .long_name = NULL_IF_CONFIG_SMALL("PGMYUV (Portable GrayMap YUV) image"),
217 };
218 #endif
219 
220 #if CONFIG_PPM_DECODER
221 AVCodec ff_ppm_decoder = {
222  .name = "ppm",
223  .type = AVMEDIA_TYPE_VIDEO,
224  .id = CODEC_ID_PPM,
225  .priv_data_size = sizeof(PNMContext),
226  .init = ff_pnm_init,
227  .close = ff_pnm_end,
229  .capabilities = CODEC_CAP_DR1,
230  .pix_fmts = (const enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGB48BE, PIX_FMT_NONE},
231  .long_name = NULL_IF_CONFIG_SMALL("PPM (Portable PixelMap) image"),
232 };
233 #endif
234 
235 #if CONFIG_PBM_DECODER
236 AVCodec ff_pbm_decoder = {
237  .name = "pbm",
238  .type = AVMEDIA_TYPE_VIDEO,
239  .id = CODEC_ID_PBM,
240  .priv_data_size = sizeof(PNMContext),
241  .init = ff_pnm_init,
242  .close = ff_pnm_end,
244  .capabilities = CODEC_CAP_DR1,
245  .pix_fmts = (const enum PixelFormat[]){PIX_FMT_MONOWHITE, PIX_FMT_NONE},
246  .long_name = NULL_IF_CONFIG_SMALL("PBM (Portable BitMap) image"),
247 };
248 #endif
249 
250 #if CONFIG_PAM_DECODER
251 AVCodec ff_pam_decoder = {
252  .name = "pam",
253  .type = AVMEDIA_TYPE_VIDEO,
254  .id = CODEC_ID_PAM,
255  .priv_data_size = sizeof(PNMContext),
256  .init = ff_pnm_init,
257  .close = ff_pnm_end,
259  .capabilities = CODEC_CAP_DR1,
261  .long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),
262 };
263 #endif