FFmpeg
loco.c
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1 /*
2  * LOCO codec
3  * Copyright (c) 2005 Konstantin Shishkov
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  * LOCO codec.
25  */
26 
27 #include "avcodec.h"
28 #include "get_bits.h"
29 #include "golomb.h"
30 #include "internal.h"
31 #include "mathops.h"
32 
33 enum LOCO_MODE {
34  LOCO_UNKN = 0,
35  LOCO_CYUY2 = -1,
36  LOCO_CRGB = -2,
37  LOCO_CRGBA = -3,
38  LOCO_CYV12 = -4,
39  LOCO_YUY2 = 1,
40  LOCO_UYVY = 2,
41  LOCO_RGB = 3,
42  LOCO_RGBA = 4,
43  LOCO_YV12 = 5,
44 };
45 
46 typedef struct LOCOContext {
48  int lossy;
50 } LOCOContext;
51 
52 typedef struct RICEContext {
54  int save, run, run2; /* internal rice decoder state */
55  int sum, count; /* sum and count for getting rice parameter */
56  int lossy;
57 } RICEContext;
58 
60 {
61  int cnt = 0;
62  int val = r->count;
63 
64  while (r->sum > val && cnt < 9) {
65  val <<= 1;
66  cnt++;
67  }
68 
69  return cnt;
70 }
71 
72 static inline void loco_update_rice_param(RICEContext *r, int val)
73 {
74  r->sum += val;
75  r->count++;
76 
77  if (r->count == 16) {
78  r->sum >>= 1;
79  r->count >>= 1;
80  }
81 }
82 
83 static inline int loco_get_rice(RICEContext *r)
84 {
85  int v;
86  if (r->run > 0) { /* we have zero run */
87  r->run--;
89  return 0;
90  }
91  if (get_bits_left(&r->gb) < 1)
92  return INT_MIN;
93  v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
94  loco_update_rice_param(r, (v + 1) >> 1);
95  if (!v) {
96  if (r->save >= 0) {
97  r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
98  if (r->run > 1)
99  r->save += r->run + 1;
100  else
101  r->save -= 3;
102  } else
103  r->run2++;
104  } else {
105  v = ((v >> 1) + r->lossy) ^ -(v & 1);
106  if (r->run2 > 0) {
107  if (r->run2 > 2)
108  r->save += r->run2;
109  else
110  r->save -= 3;
111  r->run2 = 0;
112  }
113  }
114 
115  return v;
116 }
117 
118 /* LOCO main predictor - LOCO-I/JPEG-LS predictor */
119 static inline int loco_predict(uint8_t* data, int stride)
120 {
121  int a, b, c;
122 
123  a = data[-stride];
124  b = data[-1];
125  c = data[-stride - 1];
126 
127  return mid_pred(a, a + b - c, b);
128 }
129 
131  int stride, const uint8_t *buf, int buf_size)
132 {
133  RICEContext rc;
134  int val;
135  int ret;
136  int i, j;
137 
138  if(buf_size<=0)
139  return -1;
140 
141  if ((ret = init_get_bits8(&rc.gb, buf, buf_size)) < 0)
142  return ret;
143 
144  rc.save = 0;
145  rc.run = 0;
146  rc.run2 = 0;
147  rc.lossy = l->lossy;
148 
149  rc.sum = 8;
150  rc.count = 1;
151 
152  /* restore top left pixel */
153  val = loco_get_rice(&rc);
154  data[0] = 128 + val;
155  /* restore top line */
156  for (i = 1; i < width; i++) {
157  val = loco_get_rice(&rc);
158  data[i] = data[i - 1] + val;
159  }
160  data += stride;
161  for (j = 1; j < height; j++) {
162  /* restore left column */
163  val = loco_get_rice(&rc);
164  if (val == INT_MIN)
165  return AVERROR_INVALIDDATA;
166  data[0] = data[-stride] + val;
167  /* restore all other pixels */
168  for (i = 1; i < width; i++) {
169  val = loco_get_rice(&rc);
170  if (val == INT_MIN)
171  return -1;
172  data[i] = loco_predict(&data[i], stride) + val;
173  }
174  data += stride;
175  }
176 
177  return (get_bits_count(&rc.gb) + 7) >> 3;
178 }
179 
180 static void rotate_faulty_loco(uint8_t *data, int width, int height, int stride)
181 {
182  int y;
183 
184  for (y=1; y<height; y++) {
185  if (width>=y) {
186  memmove(data + y*stride,
187  data + y*(stride + 1),
188  (width-y));
189  if (y+1 < height)
190  memmove(data + y*stride + (width-y),
191  data + (y+1)*stride, y);
192  }
193  }
194 }
195 
197  void *data, int *got_frame,
198  AVPacket *avpkt)
199 {
200  LOCOContext * const l = avctx->priv_data;
201  const uint8_t *buf = avpkt->data;
202  int buf_size = avpkt->size;
203  AVFrame * const p = data;
204  int decoded, ret;
205 
206  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
207  return ret;
208  p->key_frame = 1;
209 
210 #define ADVANCE_BY_DECODED do { \
211  if (decoded < 0 || decoded >= buf_size) goto buf_too_small; \
212  buf += decoded; buf_size -= decoded; \
213 } while(0)
214  switch(l->mode) {
215  case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
216  decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
217  p->linesize[0], buf, buf_size);
219  decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
220  p->linesize[1], buf, buf_size);
222  decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
223  p->linesize[2], buf, buf_size);
224  break;
225  case LOCO_CYV12: case LOCO_YV12:
226  decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
227  p->linesize[0], buf, buf_size);
229  decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
230  p->linesize[2], buf, buf_size);
232  decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
233  p->linesize[1], buf, buf_size);
234  break;
235  case LOCO_CRGB: case LOCO_RGB:
236  decoded = loco_decode_plane(l, p->data[1] + p->linesize[1]*(avctx->height-1), avctx->width, avctx->height,
237  -p->linesize[1], buf, buf_size);
239  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
240  -p->linesize[0], buf, buf_size);
242  decoded = loco_decode_plane(l, p->data[2] + p->linesize[2]*(avctx->height-1), avctx->width, avctx->height,
243  -p->linesize[2], buf, buf_size);
244  if (avctx->width & 1) {
245  rotate_faulty_loco(p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height, -p->linesize[0]);
246  rotate_faulty_loco(p->data[1] + p->linesize[1]*(avctx->height-1), avctx->width, avctx->height, -p->linesize[1]);
247  rotate_faulty_loco(p->data[2] + p->linesize[2]*(avctx->height-1), avctx->width, avctx->height, -p->linesize[2]);
248  }
249  break;
250  case LOCO_CRGBA:
251  case LOCO_RGBA:
252  decoded = loco_decode_plane(l, p->data[1] + p->linesize[1]*(avctx->height-1), avctx->width, avctx->height,
253  -p->linesize[1], buf, buf_size);
255  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
256  -p->linesize[0], buf, buf_size);
258  decoded = loco_decode_plane(l, p->data[2] + p->linesize[2]*(avctx->height-1), avctx->width, avctx->height,
259  -p->linesize[2], buf, buf_size);
261  decoded = loco_decode_plane(l, p->data[3] + p->linesize[3]*(avctx->height-1), avctx->width, avctx->height,
262  -p->linesize[3], buf, buf_size);
263  break;
264  default:
265  av_assert0(0);
266  }
267 
268  if (decoded < 0 || decoded > buf_size)
269  goto buf_too_small;
270  buf_size -= decoded;
271 
272  *got_frame = 1;
273 
274  return avpkt->size - buf_size;
275 buf_too_small:
276  av_log(avctx, AV_LOG_ERROR, "Input data too small.\n");
277  return AVERROR(EINVAL);
278 }
279 
281 {
282  LOCOContext * const l = avctx->priv_data;
283  int version;
284 
285  l->avctx = avctx;
286  if (avctx->extradata_size < 12) {
287  av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
288  avctx->extradata_size);
289  return AVERROR_INVALIDDATA;
290  }
291  version = AV_RL32(avctx->extradata);
292  switch (version) {
293  case 1:
294  l->lossy = 0;
295  break;
296  case 2:
297  l->lossy = AV_RL32(avctx->extradata + 8);
298  break;
299  default:
300  l->lossy = AV_RL32(avctx->extradata + 8);
301  avpriv_request_sample(avctx, "LOCO codec version %i", version);
302  }
303 
304  if (l->lossy > 65536U) {
305  av_log(avctx, AV_LOG_ERROR, "lossy %i is too large\n", l->lossy);
306  return AVERROR_INVALIDDATA;
307  }
308 
309  l->mode = AV_RL32(avctx->extradata + 4);
310  switch (l->mode) {
311  case LOCO_CYUY2:
312  case LOCO_YUY2:
313  case LOCO_UYVY:
314  avctx->pix_fmt = AV_PIX_FMT_YUV422P;
315  break;
316  case LOCO_CRGB:
317  case LOCO_RGB:
318  avctx->pix_fmt = AV_PIX_FMT_GBRP;
319  break;
320  case LOCO_CYV12:
321  case LOCO_YV12:
322  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
323  break;
324  case LOCO_CRGBA:
325  case LOCO_RGBA:
326  avctx->pix_fmt = AV_PIX_FMT_GBRAP;
327  break;
328  default:
329  av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
330  return AVERROR_INVALIDDATA;
331  }
332  if (avctx->debug & FF_DEBUG_PICT_INFO)
333  av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
334 
335  return 0;
336 }
337 
339  .name = "loco",
340  .long_name = NULL_IF_CONFIG_SMALL("LOCO"),
341  .type = AVMEDIA_TYPE_VIDEO,
342  .id = AV_CODEC_ID_LOCO,
343  .priv_data_size = sizeof(LOCOContext),
344  .init = decode_init,
345  .decode = decode_frame,
346  .capabilities = AV_CODEC_CAP_DR1,
347 };
const char const char void * val
Definition: avisynth_c.h:863
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
Definition: loco.c:41
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
#define avpriv_request_sample(...)
planar GBR 4:4:4 24bpp
Definition: pixfmt.h:168
int size
Definition: avcodec.h:1478
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
int version
Definition: avisynth_c.h:858
static int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit, int esc_len)
read unsigned golomb rice code (jpegls).
Definition: golomb.h:428
uint8_t run
Definition: svq3.c:206
AVCodec.
Definition: avcodec.h:3481
Definition: loco.c:43
int run2
Definition: loco.c:54
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
static void rotate_faulty_loco(uint8_t *data, int width, int height, int stride)
Definition: loco.c:180
static int loco_get_rice_param(RICEContext *r)
Definition: loco.c:59
uint8_t
#define av_cold
Definition: attributes.h:82
static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height, int stride, const uint8_t *buf, int buf_size)
Definition: loco.c:130
#define FF_DEBUG_PICT_INFO
Definition: avcodec.h:2651
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
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1666
#define height
uint8_t * data
Definition: avcodec.h:1477
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:219
bitstream reader API header.
int run
Definition: loco.c:54
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:849
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * r
Definition: vf_curves.c:114
int count
Definition: loco.c:55
const char * name
Name of the codec implementation.
Definition: avcodec.h:3488
static int loco_get_rice(RICEContext *r)
Definition: loco.c:83
GLsizei count
Definition: opengl_enc.c:108
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:70
int save
Definition: loco.c:54
int lossy
Definition: loco.c:48
static void loco_update_rice_param(RICEContext *r, int val)
Definition: loco.c:72
#define b
Definition: input.c:41
static av_cold int decode_init(AVCodecContext *avctx)
Definition: loco.c:280
#define width
int width
picture width / height.
Definition: avcodec.h:1738
LOCO_MODE
Definition: loco.c:33
GetBitContext gb
Definition: loco.c:53
AVCodecContext * avctx
Definition: loco.c:47
int lossy
Definition: loco.c:56
Definition: loco.c:36
int sum
Definition: loco.c:55
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
Libavcodec external API header.
Definition: loco.c:40
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:677
int debug
debug
Definition: avcodec.h:2650
main external API structure.
Definition: avcodec.h:1565
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1964
void * buf
Definition: avisynth_c.h:766
int extradata_size
Definition: avcodec.h:1667
Definition: loco.c:42
#define mid_pred
Definition: mathops.h:97
#define ADVANCE_BY_DECODED
enum LOCO_MODE mode
Definition: loco.c:49
AVCodec ff_loco_decoder
Definition: loco.c:338
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:104
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
common internal api header.
planar GBRA 4:4:4:4 32bpp
Definition: pixfmt.h:215
static int loco_predict(uint8_t *data, int stride)
Definition: loco.c:119
void * priv_data
Definition: avcodec.h:1592
Definition: loco.c:39
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
Definition: loco.c:34
#define stride
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
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: loco.c:196
exp golomb vlc stuff
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1454
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981