fraps.c
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1 /*
2  * Fraps FPS1 decoder
3  * Copyright (c) 2005 Roine Gustafsson
4  * Copyright (c) 2006 Konstantin Shishkov
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
34 #include "avcodec.h"
35 #include "get_bits.h"
36 #include "huffman.h"
37 #include "bytestream.h"
38 #include "dsputil.h"
39 
40 #define FPS_TAG MKTAG('F', 'P', 'S', 'x')
41 
45 typedef struct FrapsContext{
51 } FrapsContext;
52 
53 
60 {
61  FrapsContext * const s = avctx->priv_data;
62 
63  avctx->coded_frame = &s->frame;
64  avctx->pix_fmt= AV_PIX_FMT_NONE; /* set in decode_frame */
65 
66  s->avctx = avctx;
67  s->tmpbuf = NULL;
68 
69  ff_dsputil_init(&s->dsp, avctx);
70 
71  return 0;
72 }
73 
78 static int huff_cmp(const void *va, const void *vb){
79  const Node *a = va, *b = vb;
80  return (a->count - b->count)*256 + a->sym - b->sym;
81 }
82 
86 static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w,
87  int h, const uint8_t *src, int size, int Uoff,
88  const int step)
89 {
90  int i, j;
91  GetBitContext gb;
92  VLC vlc;
93  Node nodes[512];
94 
95  for(i = 0; i < 256; i++)
96  nodes[i].count = bytestream_get_le32(&src);
97  size -= 1024;
98  if (ff_huff_build_tree(s->avctx, &vlc, 256, nodes, huff_cmp,
100  return -1;
101  /* we have built Huffman table and are ready to decode plane */
102 
103  /* convert bits so they may be used by standard bitreader */
104  s->dsp.bswap_buf((uint32_t *)s->tmpbuf, (const uint32_t *)src, size >> 2);
105 
106  init_get_bits(&gb, s->tmpbuf, size * 8);
107  for(j = 0; j < h; j++){
108  for(i = 0; i < w*step; i += step){
109  dst[i] = get_vlc2(&gb, vlc.table, 9, 3);
110  /* lines are stored as deltas between previous lines
111  * and we need to add 0x80 to the first lines of chroma planes
112  */
113  if(j) dst[i] += dst[i - stride];
114  else if(Uoff) dst[i] += 0x80;
115  if (get_bits_left(&gb) < 0) {
116  ff_free_vlc(&vlc);
117  return AVERROR_INVALIDDATA;
118  }
119  }
120  dst += stride;
121  }
122  ff_free_vlc(&vlc);
123  return 0;
124 }
125 
126 static int decode_frame(AVCodecContext *avctx,
127  void *data, int *got_frame,
128  AVPacket *avpkt)
129 {
130  const uint8_t *buf = avpkt->data;
131  int buf_size = avpkt->size;
132  FrapsContext * const s = avctx->priv_data;
133  AVFrame *frame = data;
134  AVFrame * const f = &s->frame;
135  uint32_t header;
136  unsigned int version,header_size;
137  unsigned int x, y;
138  const uint32_t *buf32;
139  uint32_t *luma1,*luma2,*cb,*cr;
140  uint32_t offs[4];
141  int i, j, is_chroma, planes;
142  enum AVPixelFormat pix_fmt;
143  int prev_pic_bit, expected_size;
144 
145  if (buf_size < 4) {
146  av_log(avctx, AV_LOG_ERROR, "Packet is too short\n");
147  return AVERROR_INVALIDDATA;
148  }
149 
150  header = AV_RL32(buf);
151  version = header & 0xff;
152  header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
153  prev_pic_bit = header & (1U << 31); /* bit 31 means same as previous pic */
154 
155  if (version > 5) {
156  av_log(avctx, AV_LOG_ERROR,
157  "This file is encoded with Fraps version %d. " \
158  "This codec can only decode versions <= 5.\n", version);
159  return -1;
160  }
161 
162  buf+=4;
163  if (header_size == 8)
164  buf+=4;
165 
166  pix_fmt = version & 1 ? AV_PIX_FMT_BGR24 : AV_PIX_FMT_YUVJ420P;
167  if (avctx->pix_fmt != pix_fmt && f->data[0]) {
168  avctx->release_buffer(avctx, f);
169  }
170  avctx->pix_fmt = pix_fmt;
171 
172  expected_size = header_size;
173 
174  switch (version) {
175  case 0:
176  default:
177  /* Fraps v0 is a reordered YUV420 */
178  if (!prev_pic_bit)
179  expected_size += avctx->width * avctx->height * 3 / 2;
180  if (buf_size != expected_size) {
181  av_log(avctx, AV_LOG_ERROR,
182  "Invalid frame length %d (should be %d)\n",
183  buf_size, expected_size);
184  return AVERROR_INVALIDDATA;
185  }
186 
187  if (( (avctx->width % 8) != 0) || ( (avctx->height % 2) != 0 )) {
188  av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
189  avctx->width, avctx->height);
190  return -1;
191  }
192 
193  f->reference = 1;
197  if (avctx->reget_buffer(avctx, f)) {
198  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
199  return -1;
200  }
201  f->pict_type = prev_pic_bit ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
203 
204  if (f->pict_type == AV_PICTURE_TYPE_I) {
205  buf32=(const uint32_t*)buf;
206  for(y=0; y<avctx->height/2; y++){
207  luma1=(uint32_t*)&f->data[0][ y*2*f->linesize[0] ];
208  luma2=(uint32_t*)&f->data[0][ (y*2+1)*f->linesize[0] ];
209  cr=(uint32_t*)&f->data[1][ y*f->linesize[1] ];
210  cb=(uint32_t*)&f->data[2][ y*f->linesize[2] ];
211  for(x=0; x<avctx->width; x+=8){
212  *(luma1++) = *(buf32++);
213  *(luma1++) = *(buf32++);
214  *(luma2++) = *(buf32++);
215  *(luma2++) = *(buf32++);
216  *(cr++) = *(buf32++);
217  *(cb++) = *(buf32++);
218  }
219  }
220  }
221  break;
222 
223  case 1:
224  /* Fraps v1 is an upside-down BGR24 */
225  if (!prev_pic_bit)
226  expected_size += avctx->width * avctx->height * 3;
227  if (buf_size != expected_size) {
228  av_log(avctx, AV_LOG_ERROR,
229  "Invalid frame length %d (should be %d)\n",
230  buf_size, expected_size);
231  return AVERROR_INVALIDDATA;
232  }
233 
234  f->reference = 1;
238  if (avctx->reget_buffer(avctx, f)) {
239  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
240  return -1;
241  }
242  f->pict_type = prev_pic_bit ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
244 
245  if (f->pict_type == AV_PICTURE_TYPE_I) {
246  for(y=0; y<avctx->height; y++)
247  memcpy(&f->data[0][ (avctx->height - y -1) * f->linesize[0]],
248  &buf[y*avctx->width*3],
249  3*avctx->width);
250  }
251  break;
252 
253  case 2:
254  case 4:
259  planes = 3;
260  f->reference = 1;
264  if (avctx->reget_buffer(avctx, f)) {
265  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
266  return -1;
267  }
268  /* skip frame */
269  if(buf_size == 8) {
271  f->key_frame = 0;
272  break;
273  }
275  f->key_frame = 1;
276  if ((AV_RL32(buf) != FPS_TAG)||(buf_size < (planes*1024 + 24))) {
277  av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
278  return -1;
279  }
280  for(i = 0; i < planes; i++) {
281  offs[i] = AV_RL32(buf + 4 + i * 4);
282  if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
283  av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
284  return -1;
285  }
286  }
287  offs[planes] = buf_size;
288  for(i = 0; i < planes; i++){
289  is_chroma = !!i;
291  offs[i + 1] - offs[i] - 1024);
292  if (!s->tmpbuf)
293  return AVERROR(ENOMEM);
294  if(fraps2_decode_plane(s, f->data[i], f->linesize[i], avctx->width >> is_chroma,
295  avctx->height >> is_chroma, buf + offs[i], offs[i + 1] - offs[i], is_chroma, 1) < 0) {
296  av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
297  return -1;
298  }
299  }
300  break;
301  case 3:
302  case 5:
303  /* Virtually the same as version 4, but is for RGB24 */
304  planes = 3;
305  f->reference = 1;
309  if (avctx->reget_buffer(avctx, f)) {
310  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
311  return -1;
312  }
313  /* skip frame */
314  if(buf_size == 8) {
316  f->key_frame = 0;
317  break;
318  }
320  f->key_frame = 1;
321  if ((AV_RL32(buf) != FPS_TAG)||(buf_size < (planes*1024 + 24))) {
322  av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
323  return -1;
324  }
325  for(i = 0; i < planes; i++) {
326  offs[i] = AV_RL32(buf + 4 + i * 4);
327  if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
328  av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
329  return -1;
330  }
331  }
332  offs[planes] = buf_size;
333  for(i = 0; i < planes; i++){
335  offs[i + 1] - offs[i] - 1024);
336  if (!s->tmpbuf)
337  return AVERROR(ENOMEM);
338  if(fraps2_decode_plane(s, f->data[0] + i + (f->linesize[0] * (avctx->height - 1)), -f->linesize[0],
339  avctx->width, avctx->height, buf + offs[i], offs[i + 1] - offs[i], 0, 3) < 0) {
340  av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
341  return -1;
342  }
343  }
344  // convert pseudo-YUV into real RGB
345  for(j = 0; j < avctx->height; j++){
346  for(i = 0; i < avctx->width; i++){
347  f->data[0][0 + i*3 + j*f->linesize[0]] += f->data[0][1 + i*3 + j*f->linesize[0]];
348  f->data[0][2 + i*3 + j*f->linesize[0]] += f->data[0][1 + i*3 + j*f->linesize[0]];
349  }
350  }
351  break;
352  }
353 
354  *frame = *f;
355  *got_frame = 1;
356 
357  return buf_size;
358 }
359 
360 
367 {
368  FrapsContext *s = (FrapsContext*)avctx->priv_data;
369 
370  if (s->frame.data[0])
371  avctx->release_buffer(avctx, &s->frame);
372 
373  av_freep(&s->tmpbuf);
374  return 0;
375 }
376 
377 
379  .name = "fraps",
380  .type = AVMEDIA_TYPE_VIDEO,
381  .id = AV_CODEC_ID_FRAPS,
382  .priv_data_size = sizeof(FrapsContext),
383  .init = decode_init,
384  .close = decode_end,
385  .decode = decode_frame,
386  .capabilities = CODEC_CAP_DR1,
387  .long_name = NULL_IF_CONFIG_SMALL("Fraps"),
388 };