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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 
115  if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
116  return ret;
117 
118  // Need to end in 0x320 to read the descriptor
119  buf += 20;
120  descriptor = buf[0];
121 
122  // Need to end in 0x323 to read the bits per color
123  buf += 3;
124  avctx->bits_per_raw_sample =
125  bits_per_color = buf[0];
126  buf++;
127  packing = read16(&buf, endian);
128  encoding = read16(&buf, endian);
129 
130  if (packing > 1) {
131  avpriv_report_missing_feature(avctx, "Packing %d", packing);
132  return AVERROR_PATCHWELCOME;
133  }
134  if (encoding) {
135  avpriv_report_missing_feature(avctx, "Encoding %d", encoding);
136  return AVERROR_PATCHWELCOME;
137  }
138 
139  buf += 820;
140  avctx->sample_aspect_ratio.num = read32(&buf, endian);
141  avctx->sample_aspect_ratio.den = read32(&buf, endian);
142  if (avctx->sample_aspect_ratio.num > 0 && avctx->sample_aspect_ratio.den > 0)
145  0x10000);
146  else
147  avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
148 
149  switch (descriptor) {
150  case 6: // Y
151  elements = 1;
152  break;
153  case 52: // ABGR
154  case 51: // RGBA
155  elements = 4;
156  break;
157  case 50: // RGB
158  elements = 3;
159  break;
160  default:
161  avpriv_report_missing_feature(avctx, "Descriptor %d", descriptor);
162  return AVERROR_PATCHWELCOME;
163  }
164 
165  switch (bits_per_color) {
166  case 8:
167  total_size = avctx->width * avctx->height * elements;
168  break;
169  case 10:
170  if (!packing) {
171  av_log(avctx, AV_LOG_ERROR, "Packing to 32bit required\n");
172  return -1;
173  }
174  total_size = (avctx->width * elements + 2) / 3 * 4 * avctx->height;
175  break;
176  case 12:
177  if (!packing) {
178  av_log(avctx, AV_LOG_ERROR, "Packing to 16bit required\n");
179  return -1;
180  }
181  total_size = 2 * avctx->width * avctx->height * elements;
182  break;
183  case 16:
184  total_size = 2 * avctx->width * avctx->height * elements;
185  break;
186  case 1:
187  case 32:
188  case 64:
189  avpriv_report_missing_feature(avctx, "Depth %d", bits_per_color);
190  return AVERROR_PATCHWELCOME;
191  default:
192  return AVERROR_INVALIDDATA;
193  }
194 
195  switch (1000 * descriptor + 10 * bits_per_color + endian) {
196  case 6081:
197  case 6080:
198  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
199  break;
200  case 50081:
201  case 50080:
202  avctx->pix_fmt = AV_PIX_FMT_RGB24;
203  break;
204  case 52081:
205  case 52080:
206  avctx->pix_fmt = AV_PIX_FMT_ABGR;
207  break;
208  case 51081:
209  case 51080:
210  avctx->pix_fmt = AV_PIX_FMT_RGBA;
211  break;
212  case 50100:
213  case 51100:
214  case 50101:
215  case 51101:
216  avctx->pix_fmt = AV_PIX_FMT_GBRP10;
217  break;
218  case 50120:
219  case 51120:
220  case 50121:
221  case 51121:
222  avctx->pix_fmt = AV_PIX_FMT_GBRP12;
223  break;
224  case 6161:
225  avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
226  break;
227  case 6160:
228  avctx->pix_fmt = AV_PIX_FMT_GRAY16LE;
229  break;
230  case 50161:
231  avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
232  break;
233  case 50160:
234  avctx->pix_fmt = AV_PIX_FMT_RGB48LE;
235  break;
236  case 51161:
237  avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
238  break;
239  case 51160:
240  avctx->pix_fmt = AV_PIX_FMT_RGBA64LE;
241  break;
242  default:
243  av_log(avctx, AV_LOG_ERROR, "Unsupported format\n");
244  return AVERROR_PATCHWELCOME;
245  }
246 
247  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
248  return ret;
249 
250  // Move pointer to offset from start of file
251  buf = avpkt->data + offset;
252 
253  for (i=0; i<AV_NUM_DATA_POINTERS; i++)
254  ptr[i] = p->data[i];
255 
256  if (total_size + (int64_t)offset > avpkt->size) {
257  av_log(avctx, AV_LOG_ERROR, "Overread buffer. Invalid header?\n");
258  return AVERROR_INVALIDDATA;
259  }
260  switch (bits_per_color) {
261  case 10:
262  for (x = 0; x < avctx->height; x++) {
263  uint16_t *dst[3] = {(uint16_t*)ptr[0],
264  (uint16_t*)ptr[1],
265  (uint16_t*)ptr[2]};
266  for (y = 0; y < avctx->width; y++) {
267  *dst[2]++ = read10in32(&buf, &rgbBuffer,
268  &n_datum, endian);
269  *dst[0]++ = read10in32(&buf, &rgbBuffer,
270  &n_datum, endian);
271  *dst[1]++ = read10in32(&buf, &rgbBuffer,
272  &n_datum, endian);
273  // For 10 bit, ignore alpha
274  if (elements == 4)
275  read10in32(&buf, &rgbBuffer,
276  &n_datum, endian);
277  }
278  n_datum = 0;
279  for (i = 0; i < 3; i++)
280  ptr[i] += p->linesize[i];
281  }
282  break;
283  case 12:
284  for (x = 0; x < avctx->height; x++) {
285  uint16_t *dst[3] = {(uint16_t*)ptr[0],
286  (uint16_t*)ptr[1],
287  (uint16_t*)ptr[2]};
288  for (y = 0; y < avctx->width; y++) {
289  *dst[2] = read16(&buf, endian) >> 4;
290  dst[2]++;
291  *dst[0] = read16(&buf, endian) >> 4;
292  dst[0]++;
293  *dst[1] = read16(&buf, endian) >> 4;
294  dst[1]++;
295  // For 12 bit, ignore alpha
296  if (elements == 4)
297  buf += 2;
298  }
299  for (i = 0; i < 3; i++)
300  ptr[i] += p->linesize[i];
301  }
302  break;
303  case 16:
304  elements *= 2;
305  case 8:
306  av_image_copy_plane(ptr[0], p->linesize[0],
307  buf, elements * avctx->width,
308  elements * avctx->width, avctx->height);
309  break;
310  }
311 
312  *got_frame = 1;
313 
314  return buf_size;
315 }
316 
318  .name = "dpx",
319  .long_name = NULL_IF_CONFIG_SMALL("DPX (Digital Picture Exchange) image"),
320  .type = AVMEDIA_TYPE_VIDEO,
321  .id = AV_CODEC_ID_DPX,
322  .decode = decode_frame,
323  .capabilities = CODEC_CAP_DR1,
324 };