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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 FFmpeg.
7  *
8  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * Lossless Fraps 'FPS1' decoder
26  * @author Roine Gustafsson (roine at users sf net)
27  * @author Konstantin Shishkov
28  *
29  * Codec algorithm for version 0 is taken from Transcode <www.transcoding.org>
30  *
31  * Version 2 files support by Konstantin Shishkov
32  */
33 
34 #include "avcodec.h"
35 #include "get_bits.h"
36 #include "huffman.h"
37 #include "bytestream.h"
38 #include "dsputil.h"
39 #include "thread.h"
40 
41 #define FPS_TAG MKTAG('F', 'P', 'S', 'x')
42 
43 /**
44  * local variable storage
45  */
46 typedef struct FrapsContext{
52 } FrapsContext;
53 
54 
55 /**
56  * initializes decoder
57  * @param avctx codec context
58  * @return 0 on success or negative if fails
59  */
61 {
62  FrapsContext * const s = avctx->priv_data;
63 
65  avctx->coded_frame = &s->frame;
66 
67  s->avctx = avctx;
68  s->tmpbuf = NULL;
69 
70  ff_dsputil_init(&s->dsp, avctx);
71 
72  return 0;
73 }
74 
75 /**
76  * Comparator - our nodes should ascend by count
77  * but with preserved symbol order
78  */
79 static int huff_cmp(const void *va, const void *vb){
80  const Node *a = va, *b = vb;
81  return (a->count - b->count)*256 + a->sym - b->sym;
82 }
83 
84 /**
85  * decode Fraps v2 packed plane
86  */
87 static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w,
88  int h, const uint8_t *src, int size, int Uoff,
89  const int step)
90 {
91  int i, j;
92  GetBitContext gb;
93  VLC vlc;
94  Node nodes[512];
95 
96  for(i = 0; i < 256; i++)
97  nodes[i].count = bytestream_get_le32(&src);
98  size -= 1024;
99  if (ff_huff_build_tree(s->avctx, &vlc, 256, nodes, huff_cmp,
101  return -1;
102  /* we have built Huffman table and are ready to decode plane */
103 
104  /* convert bits so they may be used by standard bitreader */
105  s->dsp.bswap_buf((uint32_t *)s->tmpbuf, (const uint32_t *)src, size >> 2);
106 
107  init_get_bits(&gb, s->tmpbuf, size * 8);
108  for(j = 0; j < h; j++){
109  for(i = 0; i < w*step; i += step){
110  dst[i] = get_vlc2(&gb, vlc.table, 9, 3);
111  /* lines are stored as deltas between previous lines
112  * and we need to add 0x80 to the first lines of chroma planes
113  */
114  if(j) dst[i] += dst[i - stride];
115  else if(Uoff) dst[i] += 0x80;
116  if (get_bits_left(&gb) < 0) {
117  ff_free_vlc(&vlc);
118  return AVERROR_INVALIDDATA;
119  }
120  }
121  dst += stride;
122  }
123  ff_free_vlc(&vlc);
124  return 0;
125 }
126 
127 static int decode_frame(AVCodecContext *avctx,
128  void *data, int *got_frame,
129  AVPacket *avpkt)
130 {
131  const uint8_t *buf = avpkt->data;
132  int buf_size = avpkt->size;
133  FrapsContext * const s = avctx->priv_data;
134  AVFrame *frame = data;
135  AVFrame * const f = &s->frame;
136  uint32_t header;
137  unsigned int version,header_size;
138  unsigned int x, y;
139  const uint32_t *buf32;
140  uint32_t *luma1,*luma2,*cb,*cr;
141  uint32_t offs[4];
142  int i, j, is_chroma;
143  const int planes = 3;
144  uint8_t *out;
145  enum AVPixelFormat pix_fmt;
146  int ret;
147 
148  header = AV_RL32(buf);
149  version = header & 0xff;
150  header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
151 
152  if (version > 5) {
153  av_log(avctx, AV_LOG_ERROR,
154  "This file is encoded with Fraps version %d. " \
155  "This codec can only decode versions <= 5.\n", version);
156  return AVERROR_PATCHWELCOME;
157  }
158 
159  buf += header_size;
160 
161  if (version < 2) {
162  unsigned needed_size = avctx->width*avctx->height*3;
163  if (version == 0) needed_size /= 2;
164  needed_size += header_size;
165  /* bit 31 means same as previous pic */
166  if (header & (1U<<31)) {
167  *got_frame = 0;
168  return buf_size;
169  }
170  if (buf_size != needed_size) {
171  av_log(avctx, AV_LOG_ERROR,
172  "Invalid frame length %d (should be %d)\n",
173  buf_size, needed_size);
174  return AVERROR_INVALIDDATA;
175  }
176  } else {
177  /* skip frame */
178  if (buf_size == 8) {
179  *got_frame = 0;
180  return buf_size;
181  }
182  if (AV_RL32(buf) != FPS_TAG || buf_size < planes*1024 + 24) {
183  av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
184  return AVERROR_INVALIDDATA;
185  }
186  for(i = 0; i < planes; i++) {
187  offs[i] = AV_RL32(buf + 4 + i * 4);
188  if(offs[i] >= buf_size - header_size || (i && offs[i] <= offs[i - 1] + 1024)) {
189  av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
190  return AVERROR_INVALIDDATA;
191  }
192  }
193  offs[planes] = buf_size - header_size;
194  for(i = 0; i < planes; i++) {
195  av_fast_padded_malloc(&s->tmpbuf, &s->tmpbuf_size, offs[i + 1] - offs[i] - 1024);
196  if (!s->tmpbuf)
197  return AVERROR(ENOMEM);
198  }
199  }
200 
201  if (f->data[0])
202  ff_thread_release_buffer(avctx, f);
204  f->key_frame = 1;
205  f->reference = 0;
207 
208  pix_fmt = version & 1 ? AV_PIX_FMT_BGR24 : AV_PIX_FMT_YUVJ420P;
209  if (avctx->pix_fmt != pix_fmt && f->data[0]) {
210  avctx->release_buffer(avctx, f);
211  }
212  avctx->pix_fmt = pix_fmt;
213 
214  if ((ret = ff_thread_get_buffer(avctx, f))) {
215  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
216  return ret;
217  }
218 
219  switch(version) {
220  case 0:
221  default:
222  /* Fraps v0 is a reordered YUV420 */
223  if ( (avctx->width % 8) != 0 || (avctx->height % 2) != 0 ) {
224  av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
225  avctx->width, avctx->height);
226  return AVERROR_INVALIDDATA;
227  }
228 
229  buf32=(const uint32_t*)buf;
230  for(y=0; y<avctx->height/2; y++){
231  luma1=(uint32_t*)&f->data[0][ y*2*f->linesize[0] ];
232  luma2=(uint32_t*)&f->data[0][ (y*2+1)*f->linesize[0] ];
233  cr=(uint32_t*)&f->data[1][ y*f->linesize[1] ];
234  cb=(uint32_t*)&f->data[2][ y*f->linesize[2] ];
235  for(x=0; x<avctx->width; x+=8){
236  *luma1++ = *buf32++;
237  *luma1++ = *buf32++;
238  *luma2++ = *buf32++;
239  *luma2++ = *buf32++;
240  *cr++ = *buf32++;
241  *cb++ = *buf32++;
242  }
243  }
244  break;
245 
246  case 1:
247  /* Fraps v1 is an upside-down BGR24 */
248  for(y=0; y<avctx->height; y++)
249  memcpy(&f->data[0][ (avctx->height - y -1) * f->linesize[0]],
250  &buf[y*avctx->width*3],
251  3*avctx->width);
252  break;
253 
254  case 2:
255  case 4:
256  /**
257  * Fraps v2 is Huffman-coded YUV420 planes
258  * Fraps v4 is virtually the same
259  */
260  for(i = 0; i < planes; i++){
261  is_chroma = !!i;
262  if(fraps2_decode_plane(s, f->data[i], f->linesize[i], avctx->width >> is_chroma,
263  avctx->height >> is_chroma, buf + offs[i], offs[i + 1] - offs[i], is_chroma, 1) < 0) {
264  av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
265  return AVERROR_INVALIDDATA;
266  }
267  }
268  break;
269  case 3:
270  case 5:
271  /* Virtually the same as version 4, but is for RGB24 */
272  for(i = 0; i < planes; i++){
273  if(fraps2_decode_plane(s, f->data[0] + i + (f->linesize[0] * (avctx->height - 1)), -f->linesize[0],
274  avctx->width, avctx->height, buf + offs[i], offs[i + 1] - offs[i], 0, 3) < 0) {
275  av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
276  return AVERROR_INVALIDDATA;
277  }
278  }
279  out = f->data[0];
280  // convert pseudo-YUV into real RGB
281  for(j = 0; j < avctx->height; j++){
282  uint8_t *line_end = out + 3*avctx->width;
283  while (out < line_end) {
284  out[0] += out[1];
285  out[2] += out[1];
286  out += 3;
287  }
288  out += f->linesize[0] - 3*avctx->width;
289  }
290  break;
291  }
292 
293  *frame = *f;
294  *got_frame = 1;
295 
296  return buf_size;
297 }
298 
299 
300 /**
301  * closes decoder
302  * @param avctx codec context
303  * @return 0 on success or negative if fails
304  */
306 {
307  FrapsContext *s = (FrapsContext*)avctx->priv_data;
308 
309  if (s->frame.data[0])
310  avctx->release_buffer(avctx, &s->frame);
311 
312  av_freep(&s->tmpbuf);
313  return 0;
314 }
315 
316 
318  .name = "fraps",
319  .type = AVMEDIA_TYPE_VIDEO,
320  .id = AV_CODEC_ID_FRAPS,
321  .priv_data_size = sizeof(FrapsContext),
322  .init = decode_init,
323  .close = decode_end,
324  .decode = decode_frame,
325  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
326  .long_name = NULL_IF_CONFIG_SMALL("Fraps"),
327 };