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dpx.c
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1 /*
2  * DPX (.dpx) image decoder
3  * Copyright (c) 2009 Jimmy Christensen
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 "libavutil/intreadwrite.h"
23 #include "libavutil/imgutils.h"
24 #include "bytestream.h"
25 #include "avcodec.h"
26 #include "internal.h"
27 
28 static unsigned int read16(const uint8_t **ptr, int is_big)
29 {
30  unsigned int temp;
31  if (is_big) {
32  temp = AV_RB16(*ptr);
33  } else {
34  temp = AV_RL16(*ptr);
35  }
36  *ptr += 2;
37  return temp;
38 }
39 
40 static unsigned int read32(const uint8_t **ptr, int is_big)
41 {
42  unsigned int temp;
43  if (is_big) {
44  temp = AV_RB32(*ptr);
45  } else {
46  temp = AV_RL32(*ptr);
47  }
48  *ptr += 4;
49  return temp;
50 }
51 
52 static uint16_t read10in32(const uint8_t **ptr, uint32_t * lbuf,
53  int * n_datum, int is_big)
54 {
55  if (*n_datum)
56  (*n_datum)--;
57  else {
58  *lbuf = read32(ptr, is_big);
59  *n_datum = 2;
60  }
61 
62  *lbuf = (*lbuf << 10) | (*lbuf >> 22);
63 
64  return *lbuf & 0x3FF;
65 }
66 
67 static int decode_frame(AVCodecContext *avctx,
68  void *data,
69  int *got_frame,
70  AVPacket *avpkt)
71 {
72  const uint8_t *buf = avpkt->data;
73  int buf_size = avpkt->size;
74  AVFrame *const p = data;
76 
77  unsigned int offset;
78  int magic_num, endian;
79  int x, y, i, ret;
80  int w, h, bits_per_color, descriptor, elements, packing, total_size;
81  int encoding;
82 
83  unsigned int rgbBuffer = 0;
84  int n_datum = 0;
85 
86  if (avpkt->size <= 1634) {
87  av_log(avctx, AV_LOG_ERROR, "Packet too small for DPX header\n");
88  return AVERROR_INVALIDDATA;
89  }
90 
91  magic_num = AV_RB32(buf);
92  buf += 4;
93 
94  /* Check if the files "magic number" is "SDPX" which means it uses
95  * big-endian or XPDS which is for little-endian files */
96  if (magic_num == AV_RL32("SDPX")) {
97  endian = 0;
98  } else if (magic_num == AV_RB32("SDPX")) {
99  endian = 1;
100  } else {
101  av_log(avctx, AV_LOG_ERROR, "DPX marker not found\n");
102  return AVERROR_INVALIDDATA;
103  }
104 
105  offset = read32(&buf, endian);
106  if (avpkt->size <= offset) {
107  av_log(avctx, AV_LOG_ERROR, "Invalid data start offset\n");
108  return AVERROR_INVALIDDATA;
109  }
110  // Need to end in 0x304 offset from start of file
111  buf = avpkt->data + 0x304;
112  w = read32(&buf, endian);
113  h = read32(&buf, endian);
114  if ((ret = av_image_check_size(w, h, 0, avctx)) < 0)
115  return ret;
116 
117  if (w != avctx->width || h != avctx->height)
118  avcodec_set_dimensions(avctx, w, h);
119 
120  // Need to end in 0x320 to read the descriptor
121  buf += 20;
122  descriptor = buf[0];
123 
124  // Need to end in 0x323 to read the bits per color
125  buf += 3;
126  avctx->bits_per_raw_sample =
127  bits_per_color = buf[0];
128  buf++;
129  packing = read16(&buf, endian);
130  encoding = read16(&buf, endian);
131 
132  if (packing > 1) {
133  avpriv_report_missing_feature(avctx, "Packing %d", packing);
134  return AVERROR_PATCHWELCOME;
135  }
136  if (encoding) {
137  avpriv_report_missing_feature(avctx, "Encoding %d", encoding);
138  return AVERROR_PATCHWELCOME;
139  }
140 
141  buf += 820;
142  avctx->sample_aspect_ratio.num = read32(&buf, endian);
143  avctx->sample_aspect_ratio.den = read32(&buf, endian);
144  if (avctx->sample_aspect_ratio.num > 0 && avctx->sample_aspect_ratio.den > 0)
147  0x10000);
148  else
149  avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
150 
151  switch (descriptor) {
152  case 6: // Y
153  elements = 1;
154  break;
155  case 52: // ABGR
156  case 51: // RGBA
157  elements = 4;
158  break;
159  case 50: // RGB
160  elements = 3;
161  break;
162  default:
163  avpriv_report_missing_feature(avctx, "Descriptor %d", descriptor);
164  return AVERROR_PATCHWELCOME;
165  }
166 
167  switch (bits_per_color) {
168  case 8:
169  total_size = avctx->width * avctx->height * elements;
170  break;
171  case 10:
172  if (!packing) {
173  av_log(avctx, AV_LOG_ERROR, "Packing to 32bit required\n");
174  return -1;
175  }
176  total_size = (avctx->width * elements + 2) / 3 * 4 * avctx->height;
177  break;
178  case 12:
179  if (!packing) {
180  av_log(avctx, AV_LOG_ERROR, "Packing to 16bit required\n");
181  return -1;
182  }
183  total_size = 2 * avctx->width * avctx->height * elements;
184  break;
185  case 16:
186  total_size = 2 * avctx->width * avctx->height * elements;
187  break;
188  case 1:
189  case 32:
190  case 64:
191  avpriv_report_missing_feature(avctx, "Depth %d", bits_per_color);
192  return AVERROR_PATCHWELCOME;
193  default:
194  return AVERROR_INVALIDDATA;
195  }
196 
197  switch (1000 * descriptor + 10 * bits_per_color + endian) {
198  case 6081:
199  case 6080:
200  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
201  break;
202  case 50081:
203  case 50080:
204  avctx->pix_fmt = AV_PIX_FMT_RGB24;
205  break;
206  case 52081:
207  case 52080:
208  avctx->pix_fmt = AV_PIX_FMT_ABGR;
209  break;
210  case 51081:
211  case 51080:
212  avctx->pix_fmt = AV_PIX_FMT_RGBA;
213  break;
214  case 50100:
215  case 51100:
216  case 50101:
217  case 51101:
218  avctx->pix_fmt = AV_PIX_FMT_GBRP10;
219  break;
220  case 50120:
221  case 51120:
222  case 50121:
223  case 51121:
224  avctx->pix_fmt = AV_PIX_FMT_GBRP12;
225  break;
226  case 6161:
227  avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
228  break;
229  case 6160:
230  avctx->pix_fmt = AV_PIX_FMT_GRAY16LE;
231  break;
232  case 50161:
233  avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
234  break;
235  case 50160:
236  avctx->pix_fmt = AV_PIX_FMT_RGB48LE;
237  break;
238  case 51161:
239  avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
240  break;
241  case 51160:
242  avctx->pix_fmt = AV_PIX_FMT_RGBA64LE;
243  break;
244  default:
245  av_log(avctx, AV_LOG_ERROR, "Unsupported format\n");
246  return AVERROR_PATCHWELCOME;
247  }
248 
249  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
250  return ret;
251 
252  // Move pointer to offset from start of file
253  buf = avpkt->data + offset;
254 
255  for (i=0; i<AV_NUM_DATA_POINTERS; i++)
256  ptr[i] = p->data[i];
257 
258  if (total_size + (int64_t)offset > avpkt->size) {
259  av_log(avctx, AV_LOG_ERROR, "Overread buffer. Invalid header?\n");
260  return AVERROR_INVALIDDATA;
261  }
262  switch (bits_per_color) {
263  case 10:
264  for (x = 0; x < avctx->height; x++) {
265  uint16_t *dst[3] = {(uint16_t*)ptr[0],
266  (uint16_t*)ptr[1],
267  (uint16_t*)ptr[2]};
268  for (y = 0; y < avctx->width; y++) {
269  *dst[2]++ = read10in32(&buf, &rgbBuffer,
270  &n_datum, endian);
271  *dst[0]++ = read10in32(&buf, &rgbBuffer,
272  &n_datum, endian);
273  *dst[1]++ = read10in32(&buf, &rgbBuffer,
274  &n_datum, endian);
275  // For 10 bit, ignore alpha
276  if (elements == 4)
277  read10in32(&buf, &rgbBuffer,
278  &n_datum, endian);
279  }
280  n_datum = 0;
281  for (i = 0; i < 3; i++)
282  ptr[i] += p->linesize[i];
283  }
284  break;
285  case 12:
286  for (x = 0; x < avctx->height; x++) {
287  uint16_t *dst[3] = {(uint16_t*)ptr[0],
288  (uint16_t*)ptr[1],
289  (uint16_t*)ptr[2]};
290  for (y = 0; y < avctx->width; y++) {
291  *dst[2] = read16(&buf, endian) >> 4;
292  dst[2]++;
293  *dst[0] = read16(&buf, endian) >> 4;
294  dst[0]++;
295  *dst[1] = read16(&buf, endian) >> 4;
296  dst[1]++;
297  // For 12 bit, ignore alpha
298  if (elements == 4)
299  buf += 2;
300  }
301  for (i = 0; i < 3; i++)
302  ptr[i] += p->linesize[i];
303  }
304  break;
305  case 16:
306  elements *= 2;
307  case 8:
308  av_image_copy_plane(ptr[0], p->linesize[0],
309  buf, elements * avctx->width,
310  elements * avctx->width, avctx->height);
311  break;
312  }
313 
314  *got_frame = 1;
315 
316  return buf_size;
317 }
318 
320  .name = "dpx",
321  .long_name = NULL_IF_CONFIG_SMALL("DPX (Digital Picture Exchange) image"),
322  .type = AVMEDIA_TYPE_VIDEO,
323  .id = AV_CODEC_ID_DPX,
324  .decode = decode_frame,
325  .capabilities = CODEC_CAP_DR1,
326 };