FFmpeg  2.1.1
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;
49  int mode;
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  v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
92  loco_update_rice_param(r, (v + 1) >> 1);
93  if (!v) {
94  if (r->save >= 0) {
95  r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
96  if (r->run > 1)
97  r->save += r->run + 1;
98  else
99  r->save -= 3;
100  } else
101  r->run2++;
102  } else {
103  v = ((v >> 1) + r->lossy) ^ -(v & 1);
104  if (r->run2 > 0) {
105  if (r->run2 > 2)
106  r->save += r->run2;
107  else
108  r->save -= 3;
109  r->run2 = 0;
110  }
111  }
112 
113  return v;
114 }
115 
116 /* LOCO main predictor - LOCO-I/JPEG-LS predictor */
117 static inline int loco_predict(uint8_t* data, int stride, int step)
118 {
119  int a, b, c;
120 
121  a = data[-stride];
122  b = data[-step];
123  c = data[-stride - step];
124 
125  return mid_pred(a, a + b - c, b);
126 }
127 
129  int stride, const uint8_t *buf, int buf_size, int step)
130 {
131  RICEContext rc;
132  int val;
133  int i, j;
134 
135  if(buf_size<=0)
136  return -1;
137 
138  init_get_bits8(&rc.gb, buf, buf_size);
139  rc.save = 0;
140  rc.run = 0;
141  rc.run2 = 0;
142  rc.lossy = l->lossy;
143 
144  rc.sum = 8;
145  rc.count = 1;
146 
147  /* restore top left pixel */
148  val = loco_get_rice(&rc);
149  data[0] = 128 + val;
150  /* restore top line */
151  for (i = 1; i < width; i++) {
152  val = loco_get_rice(&rc);
153  data[i * step] = data[i * step - step] + val;
154  }
155  data += stride;
156  for (j = 1; j < height; j++) {
157  /* restore left column */
158  val = loco_get_rice(&rc);
159  data[0] = data[-stride] + val;
160  /* restore all other pixels */
161  for (i = 1; i < width; i++) {
162  val = loco_get_rice(&rc);
163  data[i * step] = loco_predict(&data[i * step], stride, step) + val;
164  }
165  data += stride;
166  }
167 
168  return (get_bits_count(&rc.gb) + 7) >> 3;
169 }
170 
171 static int decode_frame(AVCodecContext *avctx,
172  void *data, int *got_frame,
173  AVPacket *avpkt)
174 {
175  LOCOContext * const l = avctx->priv_data;
176  const uint8_t *buf = avpkt->data;
177  int buf_size = avpkt->size;
178  AVFrame * const p = data;
179  int decoded, ret;
180 
181  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
182  return ret;
183  p->key_frame = 1;
184 
185 #define ADVANCE_BY_DECODED do { \
186  if (decoded < 0 || decoded >= buf_size) goto buf_too_small; \
187  buf += decoded; buf_size -= decoded; \
188 } while(0)
189  switch(l->mode) {
190  case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
191  decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
192  p->linesize[0], buf, buf_size, 1);
194  decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
195  p->linesize[1], buf, buf_size, 1);
197  decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
198  p->linesize[2], buf, buf_size, 1);
199  break;
200  case LOCO_CYV12: case LOCO_YV12:
201  decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
202  p->linesize[0], buf, buf_size, 1);
204  decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
205  p->linesize[2], buf, buf_size, 1);
207  decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
208  p->linesize[1], buf, buf_size, 1);
209  break;
210  case LOCO_CRGB: case LOCO_RGB:
211  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
212  -p->linesize[0], buf, buf_size, 3);
214  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
215  -p->linesize[0], buf, buf_size, 3);
217  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
218  -p->linesize[0], buf, buf_size, 3);
219  break;
220  case LOCO_CRGBA:
221  case LOCO_RGBA:
222  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
223  -p->linesize[0], buf, buf_size, 4);
225  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
226  -p->linesize[0], buf, buf_size, 4);
228  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
229  -p->linesize[0], buf, buf_size, 4);
231  decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 3, avctx->width, avctx->height,
232  -p->linesize[0], buf, buf_size, 4);
233  break;
234  default:
235  av_assert0(0);
236  }
237 
238  if (decoded < 0 || decoded > buf_size)
239  goto buf_too_small;
240  buf_size -= decoded;
241 
242  *got_frame = 1;
243 
244  return avpkt->size - buf_size;
245 buf_too_small:
246  av_log(avctx, AV_LOG_ERROR, "Input data too small.\n");
247  return AVERROR(EINVAL);
248 }
249 
251 {
252  LOCOContext * const l = avctx->priv_data;
253  int version;
254 
255  l->avctx = avctx;
256  if (avctx->extradata_size < 12) {
257  av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
258  avctx->extradata_size);
259  return AVERROR_INVALIDDATA;
260  }
261  version = AV_RL32(avctx->extradata);
262  switch (version) {
263  case 1:
264  l->lossy = 0;
265  break;
266  case 2:
267  l->lossy = AV_RL32(avctx->extradata + 8);
268  break;
269  default:
270  l->lossy = AV_RL32(avctx->extradata + 8);
271  avpriv_request_sample(avctx, "LOCO codec version %i", version);
272  }
273 
274  l->mode = AV_RL32(avctx->extradata + 4);
275  switch (l->mode) {
276  case LOCO_CYUY2:
277  case LOCO_YUY2:
278  case LOCO_UYVY:
279  avctx->pix_fmt = AV_PIX_FMT_YUV422P;
280  break;
281  case LOCO_CRGB:
282  case LOCO_RGB:
283  avctx->pix_fmt = AV_PIX_FMT_BGR24;
284  break;
285  case LOCO_CYV12:
286  case LOCO_YV12:
287  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
288  break;
289  case LOCO_CRGBA:
290  case LOCO_RGBA:
291  avctx->pix_fmt = AV_PIX_FMT_BGRA;
292  break;
293  default:
294  av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
295  return AVERROR_INVALIDDATA;
296  }
297  if (avctx->debug & FF_DEBUG_PICT_INFO)
298  av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
299 
300  return 0;
301 }
302 
304  .name = "loco",
305  .long_name = NULL_IF_CONFIG_SMALL("LOCO"),
306  .type = AVMEDIA_TYPE_VIDEO,
307  .id = AV_CODEC_ID_LOCO,
308  .priv_data_size = sizeof(LOCOContext),
309  .init = decode_init,
310  .decode = decode_frame,
311  .capabilities = CODEC_CAP_DR1,
312 };
const char const char void * val
Definition: avisynth_c.h:671
float v
This structure describes decoded (raw) audio or video data.
Definition: frame.h:96
Definition: loco.c:41
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
static int loco_predict(uint8_t *data, int stride, int step)
Definition: loco.c:117
planar YUV 4:2:2, 16bpp, (1 Cr &amp; Cb sample per 2x1 Y samples)
Definition: avcodec.h:4538
int size
Definition: avcodec.h:1064
const char * b
Definition: vf_curves.c:105
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1342
int version
Definition: avisynth_c.h:666
static int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit, int esc_len)
read unsigned golomb rice code (jpegls).
Definition: golomb.h:305
int stride
Definition: mace.c:144
AVCodec.
Definition: avcodec.h:2922
#define av_cold
Definition: avcodec.h:653
Definition: loco.c:43
int run2
Definition: loco.c:54
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1254
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: avcodec.h:4537
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
static int loco_get_rice_param(RICEContext *r)
Definition: loco.c:59
uint8_t
const char * name
Name of the codec implementation.
Definition: avcodec.h:2929
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:742
const char data[16]
Definition: mxf.c:68
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:207
bitstream reader API header.
int run
Definition: loco.c:54
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: avcodec.h:4147
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
const char * r
Definition: vf_curves.c:103
int count
Definition: loco.c:55
static int loco_get_rice(RICEContext *r)
Definition: loco.c:83
Libavcodec external API header.
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
static av_cold int decode_init(AVCodecContext *avctx)
Definition: loco.c:250
ret
Definition: avfilter.c:961
int width
picture width / height.
Definition: avcodec.h:1314
LOCO_MODE
Definition: loco.c:33
GetBitContext gb
Definition: loco.c:53
static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height, int stride, const uint8_t *buf, int buf_size, int step)
Definition: loco.c:128
AVCodecContext * avctx
Definition: loco.c:47
int lossy
Definition: loco.c:56
Definition: loco.c:36
int sum
Definition: loco.c:55
planar YUV 4:2:0, 12bpp, (1 Cr &amp; Cb sample per 2x2 Y samples)
Definition: avcodec.h:4534
static int width
Definition: utils.c:158
#define AV_LOG_INFO
Standard information.
Definition: avcodec.h:4158
Definition: loco.c:40
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:436
int debug
debug
Definition: avcodec.h:2442
main external API structure.
Definition: avcodec.h:1146
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:941
void * buf
Definition: avisynth_c.h:594
int extradata_size
Definition: avcodec.h:1255
BYTE int const BYTE int int int height
Definition: avisynth_c.h:713
uint8_t * data
Definition: avcodec.h:1063
Definition: loco.c:42
#define mid_pred
Definition: mathops.h:94
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:124
#define ADVANCE_BY_DECODED
AVCodec ff_loco_decoder
Definition: loco.c:303
void * priv_data
Definition: avcodec.h:1182
#define FF_DEBUG_PICT_INFO
Definition: avcodec.h:2443
common internal api header.
static double c[64]
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: avcodec.h:4565
#define AVERROR_INVALIDDATA
#define AV_RL32(x)
Definition: intreadwrite.h:275
Definition: loco.c:39
int key_frame
1 -&gt; keyframe, 0-&gt; not
Definition: frame.h:162
#define AVERROR(e)
Definition: loco.c:34
static int decode(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: crystalhd.c:868
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
int mode
Definition: loco.c:49
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: loco.c:171
exp golomb vlc stuff
This structure stores compressed data.
Definition: avcodec.h:1040
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:107