FFmpeg
cdtoons.c
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1 /*
2  * CDToons video decoder
3  * Copyright (C) 2020 Alyssa Milburn <amilburn@zall.org>
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 /**
23  * @file
24  * CDToons video decoder
25  * @author Alyssa Milburn <amilburn@zall.org>
26  */
27 
28 #include <stdint.h>
29 
30 #include "libavutil/attributes.h"
31 #include "libavutil/internal.h"
32 #include "libavutil/mem.h"
33 #include "avcodec.h"
34 #include "bytestream.h"
35 #include "codec_internal.h"
36 #include "decode.h"
37 
38 #define CDTOONS_HEADER_SIZE 44
39 #define CDTOONS_MAX_SPRITES 1200
40 
41 typedef struct CDToonsSprite {
42  uint16_t flags;
43  uint16_t owner_frame;
44  uint16_t start_frame;
45  uint16_t end_frame;
46  unsigned int alloc_size;
47  uint32_t size;
48  uint8_t *data;
49  int active;
51 
52 typedef struct CDToonsContext {
54 
55  uint16_t last_pal_id; ///< The index of the active palette sprite.
56  uint32_t pal[256]; ///< The currently-used palette data.
59 
60 static int cdtoons_render_sprite(AVCodecContext *avctx, const uint8_t *data,
61  uint32_t data_size,
62  int dst_x, int dst_y, int width, int height)
63 {
64  CDToonsContext *c = avctx->priv_data;
65  const uint8_t *next_line = data;
66  const uint8_t *end = data + data_size;
67  uint16_t line_size;
68  uint8_t *dest;
69  int skip = 0, to_skip, x;
70 
71  if (dst_x + width > avctx->width)
72  width = avctx->width - dst_x;
73  if (dst_y + height > avctx->height)
74  height = avctx->height - dst_y;
75 
76  if (dst_x < 0) {
77  /* we need to skip the start of the scanlines */
78  skip = -dst_x;
79  if (width <= skip)
80  return 0;
81  dst_x = 0;
82  }
83 
84  for (int y = 0; y < height; y++) {
85  /* one scanline at a time, size is provided */
86  data = next_line;
87  if (end - data < 2)
88  return 1;
89  line_size = bytestream_get_be16(&data);
90  if (end - data < line_size)
91  return 1;
92  next_line = data + line_size;
93  if (dst_y + y < 0)
94  continue;
95 
96  dest = c->frame->data[0] + (dst_y + y) * c->frame->linesize[0] + dst_x;
97 
98  to_skip = skip;
99  x = 0;
100  while (x < width - skip) {
101  int raw, size, step;
102  uint8_t val;
103 
104  if (data >= end)
105  return 1;
106 
107  val = bytestream_get_byte(&data);
108  raw = !(val & 0x80);
109  size = (int)(val & 0x7F) + 1;
110 
111  /* skip the start of a scanline if it is off-screen */
112  if (to_skip >= size) {
113  to_skip -= size;
114  if (raw) {
115  step = size;
116  } else {
117  step = 1;
118  }
119  if (next_line - data < step)
120  return 1;
121  data += step;
122  continue;
123  } else if (to_skip) {
124  size -= to_skip;
125  if (raw) {
126  if (next_line - data < to_skip)
127  return 1;
128  data += to_skip;
129  }
130  to_skip = 0;
131  }
132 
133  if (x + size >= width - skip)
134  size = width - skip - x;
135 
136  /* either raw data, or a run of a single color */
137  if (raw) {
138  if (next_line - data < size)
139  return 1;
140  memcpy(dest + x, data, size);
141  data += size;
142  } else {
143  uint8_t color = bytestream_get_byte(&data);
144  /* ignore transparent runs */
145  if (color)
146  memset(dest + x, color, size);
147  }
148  x += size;
149  }
150  }
151 
152  return 0;
153 }
154 
155 static int cdtoons_decode_frame(AVCodecContext *avctx, AVFrame *rframe,
156  int *got_frame, AVPacket *avpkt)
157 {
158  CDToonsContext *c = avctx->priv_data;
159  const uint8_t *buf = avpkt->data;
160  const uint8_t *eod = avpkt->data + avpkt->size;
161  const int buf_size = avpkt->size;
162  uint16_t frame_id;
163  uint8_t background_color;
164  uint16_t sprite_count, sprite_offset;
165  uint8_t referenced_count;
166  uint16_t palette_id;
167  uint8_t palette_set;
168  int ret;
169  int saw_embedded_sprites = 0;
170 
171  if (buf_size < CDTOONS_HEADER_SIZE)
172  return AVERROR_INVALIDDATA;
173 
174  if ((ret = ff_reget_buffer(avctx, c->frame, 0)) < 0)
175  return ret;
176 
177  /* a lot of the header is useless junk in the absence of
178  * dirty rectangling etc */
179  buf += 2; /* version? (always 9?) */
180  frame_id = bytestream_get_be16(&buf);
181  buf += 2; /* blocks_valid_until */
182  buf += 1;
183  background_color = bytestream_get_byte(&buf);
184  buf += 16; /* clip rect, dirty rect */
185  buf += 4; /* flags */
186  sprite_count = bytestream_get_be16(&buf);
187  sprite_offset = bytestream_get_be16(&buf);
188  buf += 2; /* max block id? */
189  referenced_count = bytestream_get_byte(&buf);
190  buf += 1;
191  palette_id = bytestream_get_be16(&buf);
192  palette_set = bytestream_get_byte(&buf);
193  buf += 5;
194 
195  if (sprite_offset > buf_size)
196  return AVERROR_INVALIDDATA;
197 
198  /* read new sprites introduced in this frame */
199  buf = avpkt->data + sprite_offset;
200  while (sprite_count--) {
201  uint32_t size;
202  uint16_t sprite_id;
203 
204  if (buf + 14 > eod)
205  return AVERROR_INVALIDDATA;
206 
207  sprite_id = bytestream_get_be16(&buf);
208  if (sprite_id >= CDTOONS_MAX_SPRITES) {
209  av_log(avctx, AV_LOG_ERROR,
210  "Sprite ID %d is too high.\n", sprite_id);
211  return AVERROR_INVALIDDATA;
212  }
213  if (c->sprites[sprite_id].active) {
214  av_log(avctx, AV_LOG_ERROR,
215  "Sprite ID %d is a duplicate.\n", sprite_id);
216  return AVERROR_INVALIDDATA;
217  }
218 
219  c->sprites[sprite_id].flags = bytestream_get_be16(&buf);
220  size = bytestream_get_be32(&buf);
221  if (size < 14) {
222  av_log(avctx, AV_LOG_ERROR,
223  "Sprite only has %d bytes of data.\n", size);
224  return AVERROR_INVALIDDATA;
225  }
226  size -= 14;
227  c->sprites[sprite_id].size = size;
228  c->sprites[sprite_id].owner_frame = frame_id;
229  c->sprites[sprite_id].start_frame = bytestream_get_be16(&buf);
230  c->sprites[sprite_id].end_frame = bytestream_get_be16(&buf);
231  buf += 2;
232 
233  if (size > buf_size || buf + size > eod)
234  return AVERROR_INVALIDDATA;
235 
236  av_fast_padded_malloc(&c->sprites[sprite_id].data, &c->sprites[sprite_id].alloc_size, size);
237  if (!c->sprites[sprite_id].data)
238  return AVERROR(ENOMEM);
239 
240  c->sprites[sprite_id].active = 1;
241 
242  bytestream_get_buffer(&buf, c->sprites[sprite_id].data, size);
243  }
244 
245  /* render any embedded sprites */
246  while (buf < eod) {
247  uint32_t tag, size;
248  if (buf + 8 > eod) {
249  av_log(avctx, AV_LOG_WARNING, "Ran (seriously) out of data for embedded sprites.\n");
250  return AVERROR_INVALIDDATA;
251  }
252  tag = bytestream_get_be32(&buf);
253  size = bytestream_get_be32(&buf);
254  if (tag == MKBETAG('D', 'i', 'f', 'f')) {
255  uint16_t diff_count;
256  if (buf + 10 > eod) {
257  av_log(avctx, AV_LOG_WARNING, "Ran (seriously) out of data for Diff frame.\n");
258  return AVERROR_INVALIDDATA;
259  }
260  diff_count = bytestream_get_be16(&buf);
261  buf += 8; /* clip rect? */
262  for (int i = 0; i < diff_count; i++) {
263  int16_t top, left;
264  uint16_t diff_size, width, height;
265 
266  if (buf + 16 > eod) {
267  av_log(avctx, AV_LOG_WARNING, "Ran (seriously) out of data for Diff frame header.\n");
268  return AVERROR_INVALIDDATA;
269  }
270 
271  top = bytestream_get_be16(&buf);
272  left = bytestream_get_be16(&buf);
273  buf += 4; /* bottom, right */
274  diff_size = bytestream_get_be32(&buf);
275  width = bytestream_get_be16(&buf);
276  height = bytestream_get_be16(&buf);
277  if (diff_size < 8 || diff_size - 4 > eod - buf) {
278  av_log(avctx, AV_LOG_WARNING, "Ran (seriously) out of data for Diff frame data.\n");
279  return AVERROR_INVALIDDATA;
280  }
281  if (cdtoons_render_sprite(avctx, buf + 4, diff_size - 8,
282  left, top, width, height)) {
283  av_log(avctx, AV_LOG_WARNING, "Ran beyond end of sprite while rendering.\n");
284  }
285  buf += diff_size - 4;
286  }
287  saw_embedded_sprites = 1;
288  } else {
289  /* we don't care about any other entries */
290  if (size < 8 || size - 8 > eod - buf) {
291  av_log(avctx, AV_LOG_WARNING, "Ran out of data for ignored entry (size %X, %d left).\n", size, (int)(eod - buf));
292  return AVERROR_INVALIDDATA;
293  }
294  buf += (size - 8);
295  }
296  }
297 
298  /* was an intra frame? */
299  if (saw_embedded_sprites)
300  goto done;
301 
302  /* render any referenced sprites */
303  buf = avpkt->data + CDTOONS_HEADER_SIZE;
304  eod = avpkt->data + sprite_offset;
305  for (int i = 0; i < referenced_count; i++) {
306  const uint8_t *block_data;
307  uint16_t sprite_id, width, height;
308  int16_t top, left, right;
309 
310  if (buf + 10 > eod) {
311  av_log(avctx, AV_LOG_WARNING, "Ran (seriously) out of data when rendering.\n");
312  return AVERROR_INVALIDDATA;
313  }
314 
315  sprite_id = bytestream_get_be16(&buf);
316  top = bytestream_get_be16(&buf);
317  left = bytestream_get_be16(&buf);
318  buf += 2; /* bottom */
319  right = bytestream_get_be16(&buf);
320 
321  if ((i == 0) && (sprite_id == 0)) {
322  /* clear background */
323  memset(c->frame->data[0], background_color,
324  c->frame->linesize[0] * avctx->height);
325  }
326 
327  if (!right)
328  continue;
329  if (sprite_id >= CDTOONS_MAX_SPRITES) {
330  av_log(avctx, AV_LOG_ERROR,
331  "Sprite ID %d is too high.\n", sprite_id);
332  return AVERROR_INVALIDDATA;
333  }
334 
335  block_data = c->sprites[sprite_id].data;
336  if (!c->sprites[sprite_id].active) {
337  /* this can happen when seeking around */
338  av_log(avctx, AV_LOG_WARNING, "Sprite %d is missing.\n", sprite_id);
339  continue;
340  }
341  if (c->sprites[sprite_id].size < 14) {
342  av_log(avctx, AV_LOG_ERROR, "Sprite %d is too small.\n", sprite_id);
343  continue;
344  }
345 
346  height = bytestream_get_be16(&block_data);
347  width = bytestream_get_be16(&block_data);
348  block_data += 10;
349  if (cdtoons_render_sprite(avctx, block_data,
350  c->sprites[sprite_id].size - 14,
351  left, top, width, height)) {
352  av_log(avctx, AV_LOG_WARNING, "Ran beyond end of sprite while rendering.\n");
353  }
354  }
355 
356  if (palette_id && (palette_id != c->last_pal_id)) {
357  if (palette_id >= CDTOONS_MAX_SPRITES) {
358  av_log(avctx, AV_LOG_ERROR,
359  "Palette ID %d is too high.\n", palette_id);
360  return AVERROR_INVALIDDATA;
361  }
362  if (!c->sprites[palette_id].active) {
363  /* this can happen when seeking around */
364  av_log(avctx, AV_LOG_WARNING,
365  "Palette ID %d is missing.\n", palette_id);
366  goto done;
367  }
368  if (c->sprites[palette_id].size != 256 * 2 * 3) {
369  av_log(avctx, AV_LOG_ERROR,
370  "Palette ID %d is wrong size (%d).\n",
371  palette_id, c->sprites[palette_id].size);
372  return AVERROR_INVALIDDATA;
373  }
374  c->last_pal_id = palette_id;
375  if (!palette_set) {
376  uint8_t *palette_data = c->sprites[palette_id].data;
377  for (int i = 0; i < 256; i++) {
378  /* QuickTime-ish palette: 16-bit RGB components */
379  unsigned r, g, b;
380  r = *palette_data;
381  g = *(palette_data + 2);
382  b = *(palette_data + 4);
383  c->pal[i] = (0xFFU << 24) | (r << 16) | (g << 8) | b;
384  palette_data += 6;
385  }
386  /* first palette entry indicates transparency */
387  c->pal[0] = 0;
388 #if FF_API_PALETTE_HAS_CHANGED
390  c->frame->palette_has_changed = 1;
392 #endif
393  }
394  }
395 
396 done:
397  /* discard outdated blocks */
398  for (int i = 0; i < CDTOONS_MAX_SPRITES; i++) {
399  if (c->sprites[i].end_frame > frame_id)
400  continue;
401  c->sprites[i].active = 0;
402  }
403 
404  memcpy(c->frame->data[1], c->pal, AVPALETTE_SIZE);
405 
406  if ((ret = av_frame_ref(rframe, c->frame)) < 0)
407  return ret;
408 
409  *got_frame = 1;
410 
411  /* always report that the buffer was completely consumed */
412  return buf_size;
413 }
414 
416 {
417  CDToonsContext *c = avctx->priv_data;
418 
419  avctx->pix_fmt = AV_PIX_FMT_PAL8;
420  c->last_pal_id = 0;
421  c->frame = av_frame_alloc();
422  if (!c->frame)
423  return AVERROR(ENOMEM);
424 
425  return 0;
426 }
427 
428 static void cdtoons_flush(AVCodecContext *avctx)
429 {
430  CDToonsContext *c = avctx->priv_data;
431 
432  c->last_pal_id = 0;
433  for (int i = 0; i < CDTOONS_MAX_SPRITES; i++)
434  c->sprites[i].active = 0;
435 }
436 
438 {
439  CDToonsContext *c = avctx->priv_data;
440 
441  for (int i = 0; i < CDTOONS_MAX_SPRITES; i++) {
442  av_freep(&c->sprites[i].data);
443  c->sprites[i].active = 0;
444  }
445 
446  av_frame_free(&c->frame);
447 
448  return 0;
449 }
450 
452  .p.name = "cdtoons",
453  CODEC_LONG_NAME("CDToons video"),
454  .p.type = AVMEDIA_TYPE_VIDEO,
455  .p.id = AV_CODEC_ID_CDTOONS,
456  .priv_data_size = sizeof(CDToonsContext),
458  .close = cdtoons_decode_end,
460  .p.capabilities = AV_CODEC_CAP_DR1,
461  .flush = cdtoons_flush,
462 };
FF_ENABLE_DEPRECATION_WARNINGS
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:73
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
CDToonsContext::frame
AVFrame * frame
Definition: cdtoons.c:53
r
const char * r
Definition: vf_curves.c:127
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
color
Definition: vf_paletteuse.c:512
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int active
Definition: cdtoons.c:49
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Definition: cdtoons.c:43
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Definition: cdtoons.c:47
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void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:160
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This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
step
trying all byte sequences megabyte in length and selecting the best looking sequence will yield cases to try But a word about which is also called distortion Distortion can be quantified by almost any quality measurement one chooses the sum of squared differences is used but more complex methods that consider psychovisual effects can be used as well It makes no difference in this discussion First step
Definition: rate_distortion.txt:58
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uint8_t * data
Definition: packet.h:524
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Definition: input.c:41
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AV_CODEC_ID_CDTOONS
@ AV_CODEC_ID_CDTOONS
Definition: codec_id.h:300
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Definition: cdtoons.c:41
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Definition: codec_internal.h:126
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Definition: cdtoons.c:45
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Definition: cdtoons.c:437
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Definition: cdtoons.c:48
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Definition: codec_internal.h:130
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Allocate an AVFrame and set its fields to default values.
Definition: frame.c:148
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#define CDTOONS_HEADER_SIZE
Definition: cdtoons.c:38
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#define AV_LOG_ERROR
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Definition: attributes.h:90
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#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:286
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Definition: cdtoons.c:155
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#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:271
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static void cdtoons_flush(AVCodecContext *avctx)
Definition: cdtoons.c:428
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#define AVPALETTE_SIZE
Definition: pixfmt.h:32
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
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#define CDTOONS_MAX_SPRITES
Definition: cdtoons.c:39
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unsigned int alloc_size
Definition: cdtoons.c:46
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Definition: codec.h:52
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Definition: packet.h:525
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int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:384
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Definition: twinvq_data.h:10344
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#define MKBETAG(a, b, c, d)
Definition: macros.h:56
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Definition: cdtoons.c:57
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uint16_t flags
Definition: cdtoons.c:42
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Definition: cdtoons.c:52
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const FFCodec ff_cdtoons_decoder
Definition: cdtoons.c:451
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Definition: cbs_h2645.c:256
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Definition: codec.h:194
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Definition: avcodec.h:657
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Definition: bytestream.h:363
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Definition: pixfmt.h:84
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Definition: movenc.c:1788
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Identical in function to ff_get_buffer(), except it reuses the existing buffer if available.
Definition: decode.c:1684
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Definition: filter_design.txt:187
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Definition: cdtoons.c:56
left
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:386
U
#define U(x)
Definition: vpx_arith.h:37
AVCodecContext
main external API structure.
Definition: avcodec.h:445
CDToonsContext::last_pal_id
uint16_t last_pal_id
The index of the active palette sprite.
Definition: cdtoons.c:55
FF_DISABLE_DEPRECATION_WARNINGS
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:72
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
mem.h
cdtoons_render_sprite
static int cdtoons_render_sprite(AVCodecContext *avctx, const uint8_t *data, uint32_t data_size, int dst_x, int dst_y, int width, int height)
Definition: cdtoons.c:60
AVPacket
This structure stores compressed data.
Definition: packet.h:501
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:618
bytestream.h
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
cdtoons_decode_init
static av_cold int cdtoons_decode_init(AVCodecContext *avctx)
Definition: cdtoons.c:415
int
int
Definition: ffmpeg_filter.c:424
CDToonsSprite::start_frame
uint16_t start_frame
Definition: cdtoons.c:44
skip
static void BS_FUNC() skip(BSCTX *bc, unsigned int n)
Skip n bits in the buffer.
Definition: bitstream_template.h:375