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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 "bswapdsp.h"
39 #include "internal.h"
40 #include "thread.h"
41 
42 #define FPS_TAG MKTAG('F', 'P', 'S', 'x')
43 #define VLC_BITS 11
44 
45 /**
46  * local variable storage
47  */
48 typedef struct FrapsContext {
53 } FrapsContext;
54 
55 
56 /**
57  * initializes decoder
58  * @param avctx codec context
59  * @return 0 on success or negative if fails
60  */
62 {
63  FrapsContext * const s = avctx->priv_data;
64 
65  s->avctx = avctx;
66  s->tmpbuf = NULL;
67 
69 
70  return 0;
71 }
72 
73 /**
74  * Comparator - our nodes should ascend by count
75  * but with preserved symbol order
76  */
77 static int huff_cmp(const void *va, const void *vb)
78 {
79  const Node *a = va, *b = vb;
80  return (a->count - b->count)*256 + a->sym - b->sym;
81 }
82 
83 /**
84  * decode Fraps v2 packed plane
85  */
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, ret;
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 ((ret = ff_huff_build_tree(s->avctx, &vlc, 256, VLC_BITS,
99  nodes, huff_cmp,
101  return ret;
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->bdsp.bswap_buf((uint32_t *) s->tmpbuf,
106  (const uint32_t *) src, size >> 2);
107 
108  init_get_bits(&gb, s->tmpbuf, size * 8);
109  for (j = 0; j < h; j++) {
110  for (i = 0; i < w*step; i += step) {
111  dst[i] = get_vlc2(&gb, vlc.table, VLC_BITS, 3);
112  /* lines are stored as deltas between previous lines
113  * and we need to add 0x80 to the first lines of chroma planes
114  */
115  if (j)
116  dst[i] += dst[i - stride];
117  else if (Uoff)
118  dst[i] += 0x80;
119  if (get_bits_left(&gb) < 0) {
120  ff_free_vlc(&vlc);
121  return AVERROR_INVALIDDATA;
122  }
123  }
124  dst += stride;
125  }
126  ff_free_vlc(&vlc);
127  return 0;
128 }
129 
130 static int decode_frame(AVCodecContext *avctx,
131  void *data, int *got_frame,
132  AVPacket *avpkt)
133 {
134  FrapsContext * const s = avctx->priv_data;
135  const uint8_t *buf = avpkt->data;
136  int buf_size = avpkt->size;
137  ThreadFrame frame = { .f = data };
138  AVFrame * const f = data;
139  uint32_t header;
140  unsigned int version,header_size;
141  unsigned int x, y;
142  const uint32_t *buf32;
143  uint32_t *luma1,*luma2,*cb,*cr;
144  uint32_t offs[4];
145  int i, j, ret, is_chroma;
146  const int planes = 3;
147  uint8_t *out;
148 
149  if (buf_size < 4) {
150  av_log(avctx, AV_LOG_ERROR, "Packet is too short\n");
151  return AVERROR_INVALIDDATA;
152  }
153 
154  header = AV_RL32(buf);
155  version = header & 0xff;
156  header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
157 
158  if (version > 5) {
159  av_log(avctx, AV_LOG_ERROR,
160  "This file is encoded with Fraps version %d. " \
161  "This codec can only decode versions <= 5.\n", version);
162  return AVERROR_PATCHWELCOME;
163  }
164 
165  buf += header_size;
166 
167  if (version < 2) {
168  unsigned needed_size = avctx->width * avctx->height * 3;
169  if (version == 0) needed_size /= 2;
170  needed_size += header_size;
171  /* bit 31 means same as previous pic */
172  if (header & (1U<<31)) {
173  *got_frame = 0;
174  return buf_size;
175  }
176  if (buf_size != needed_size) {
177  av_log(avctx, AV_LOG_ERROR,
178  "Invalid frame length %d (should be %d)\n",
179  buf_size, needed_size);
180  return AVERROR_INVALIDDATA;
181  }
182  } else {
183  /* skip frame */
184  if (buf_size == 8) {
185  *got_frame = 0;
186  return buf_size;
187  }
188  if (AV_RL32(buf) != FPS_TAG || buf_size < planes*1024 + 24) {
189  av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
190  return AVERROR_INVALIDDATA;
191  }
192  for (i = 0; i < planes; i++) {
193  offs[i] = AV_RL32(buf + 4 + i * 4);
194  if (offs[i] >= buf_size - header_size || (i && offs[i] <= offs[i - 1] + 1024)) {
195  av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
196  return AVERROR_INVALIDDATA;
197  }
198  }
199  offs[planes] = buf_size - header_size;
200  for (i = 0; i < planes; i++) {
201  av_fast_padded_malloc(&s->tmpbuf, &s->tmpbuf_size, offs[i + 1] - offs[i] - 1024);
202  if (!s->tmpbuf)
203  return AVERROR(ENOMEM);
204  }
205  }
206 
208  f->key_frame = 1;
209 
210  avctx->pix_fmt = version & 1 ? AV_PIX_FMT_BGR24 : AV_PIX_FMT_YUVJ420P;
211  avctx->color_range = version & 1 ? AVCOL_RANGE_UNSPECIFIED
213  avctx->colorspace = version & 1 ? AVCOL_SPC_UNSPECIFIED : AVCOL_SPC_BT709;
214 
215  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
216  return ret;
217 
218  switch (version) {
219  case 0:
220  default:
221  /* Fraps v0 is a reordered YUV420 */
222  if (((avctx->width % 8) != 0) || ((avctx->height % 2) != 0)) {
223  av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
224  avctx->width, avctx->height);
225  return AVERROR_INVALIDDATA;
226  }
227 
228  buf32 = (const uint32_t*)buf;
229  for (y = 0; y < avctx->height / 2; y++) {
230  luma1 = (uint32_t*)&f->data[0][ y * 2 * f->linesize[0] ];
231  luma2 = (uint32_t*)&f->data[0][ (y * 2 + 1) * f->linesize[0] ];
232  cr = (uint32_t*)&f->data[1][ y * f->linesize[1] ];
233  cb = (uint32_t*)&f->data[2][ y * f->linesize[2] ];
234  for (x = 0; x < avctx->width; x += 8) {
235  *luma1++ = *buf32++;
236  *luma1++ = *buf32++;
237  *luma2++ = *buf32++;
238  *luma2++ = *buf32++;
239  *cr++ = *buf32++;
240  *cb++ = *buf32++;
241  }
242  }
243  break;
244 
245  case 1:
246  /* Fraps v1 is an upside-down BGR24 */
247  for (y = 0; y<avctx->height; y++)
248  memcpy(&f->data[0][(avctx->height - y - 1) * f->linesize[0]],
249  &buf[y * avctx->width * 3],
250  3 * avctx->width);
251  break;
252 
253  case 2:
254  case 4:
255  /**
256  * Fraps v2 is Huffman-coded YUV420 planes
257  * Fraps v4 is virtually the same
258  */
259  for (i = 0; i < planes; i++) {
260  is_chroma = !!i;
261  if ((ret = fraps2_decode_plane(s, f->data[i], f->linesize[i],
262  avctx->width >> is_chroma,
263  avctx->height >> is_chroma,
264  buf + offs[i], offs[i + 1] - offs[i],
265  is_chroma, 1)) < 0) {
266  av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
267  return ret;
268  }
269  }
270  break;
271  case 3:
272  case 5:
273  /* Virtually the same as version 4, but is for RGB24 */
274  for (i = 0; i < planes; i++) {
275  if ((ret = fraps2_decode_plane(s, f->data[0] + i + (f->linesize[0] * (avctx->height - 1)),
276  -f->linesize[0], avctx->width, avctx->height,
277  buf + offs[i], offs[i + 1] - offs[i], 0, 3)) < 0) {
278  av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
279  return ret;
280  }
281  }
282  out = f->data[0];
283  // convert pseudo-YUV into real RGB
284  for (j = 0; j < avctx->height; j++) {
285  uint8_t *line_end = out + 3*avctx->width;
286  while (out < line_end) {
287  out[0] += out[1];
288  out[2] += out[1];
289  out += 3;
290  }
291  out += f->linesize[0] - 3*avctx->width;
292  }
293  break;
294  }
295 
296  *got_frame = 1;
297 
298  return buf_size;
299 }
300 
301 
302 /**
303  * closes decoder
304  * @param avctx codec context
305  * @return 0 on success or negative if fails
306  */
308 {
309  FrapsContext *s = (FrapsContext*)avctx->priv_data;
310 
311  av_freep(&s->tmpbuf);
312  return 0;
313 }
314 
315 
317  .name = "fraps",
318  .long_name = NULL_IF_CONFIG_SMALL("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 };