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source: vbox/trunk/src/libs/ffmpeg-20060710/libavcodec/loco.c@ 10184

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1/*
2 * LOCO codec
3 * Copyright (c) 2005 Konstantin Shishkov
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 */
20
21/**
22 * @file loco.c
23 * LOCO codec.
24 */
25
26#include "avcodec.h"
27#include "common.h"
28#include "bitstream.h"
29#include "golomb.h"
30
31enum LOCO_MODE {LOCO_UNKN=0, LOCO_CYUY2=-1, LOCO_CRGB=-2, LOCO_CRGBA=-3, LOCO_CYV12=-4,
32 LOCO_YUY2=1, LOCO_UYVY=2, LOCO_RGB=3, LOCO_RGBA=4, LOCO_YV12=5};
33
34typedef struct LOCOContext{
35 AVCodecContext *avctx;
36 AVFrame pic;
37 int lossy;
38 int mode;
39} LOCOContext;
40
41typedef struct RICEContext{
42 GetBitContext gb;
43 int save, run, run2; /* internal rice decoder state */
44 int sum, count; /* sum and count for getting rice parameter */
45 int lossy;
46}RICEContext;
47
48static int loco_get_rice_param(RICEContext *r)
49{
50 int cnt = 0;
51 int val = r->count;
52
53 while(r->sum > val && cnt < 9) {
54 val <<= 1;
55 cnt++;
56 }
57
58 return cnt;
59}
60
61static inline void loco_update_rice_param(RICEContext *r, int val)
62{
63 r->sum += val;
64 r->count++;
65
66 if(r->count == 16) {
67 r->sum >>= 1;
68 r->count >>= 1;
69 }
70}
71
72static inline int loco_get_rice(RICEContext *r)
73{
74 int v;
75 if (r->run > 0) { /* we have zero run */
76 r->run--;
77 loco_update_rice_param(r, 0);
78 return 0;
79 }
80 v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
81 loco_update_rice_param(r, (v+1)>>1);
82 if (!v) {
83 if (r->save >= 0) {
84 r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
85 if(r->run > 1)
86 r->save += r->run + 1;
87 else
88 r->save -= 3;
89 }
90 else
91 r->run2++;
92 } else {
93 v = ((v>>1) + r->lossy) ^ -(v&1);
94 if (r->run2 > 0) {
95 if (r->run2 > 2)
96 r->save += r->run2;
97 else
98 r->save -= 3;
99 r->run2 = 0;
100 }
101 }
102
103 return v;
104}
105
106/* LOCO main predictor - LOCO-I/JPEG-LS predictor */
107static inline int loco_predict(uint8_t* data, int stride, int step)
108{
109 int a, b, c;
110
111 a = data[-stride];
112 b = data[-step];
113 c = data[-stride - step];
114
115 return mid_pred(a, a + b - c, b);
116}
117
118static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
119 int stride, uint8_t *buf, int buf_size, int step)
120{
121 RICEContext rc;
122 int val;
123 int i, j;
124
125 init_get_bits(&rc.gb, buf, buf_size*8);
126 rc.save = 0;
127 rc.run = 0;
128 rc.run2 = 0;
129 rc.lossy = l->lossy;
130
131 rc.sum = 8;
132 rc.count = 1;
133
134 /* restore top left pixel */
135 val = loco_get_rice(&rc);
136 data[0] = 128 + val;
137 /* restore top line */
138 for (i = 1; i < width; i++) {
139 val = loco_get_rice(&rc);
140 data[i * step] = data[i * step - step] + val;
141 }
142 data += stride;
143 for (j = 1; j < height; j++) {
144 /* restore left column */
145 val = loco_get_rice(&rc);
146 data[0] = data[-stride] + val;
147 /* restore all other pixels */
148 for (i = 1; i < width; i++) {
149 val = loco_get_rice(&rc);
150 data[i * step] = loco_predict(&data[i * step], stride, step) + val;
151 }
152 data += stride;
153 }
154
155 return ((get_bits_count(&rc.gb) + 7) >> 3);
156}
157
158static int decode_frame(AVCodecContext *avctx,
159 void *data, int *data_size,
160 uint8_t *buf, int buf_size)
161{
162 LOCOContext * const l = avctx->priv_data;
163 AVFrame * const p= (AVFrame*)&l->pic;
164 int decoded;
165
166 if(p->data[0])
167 avctx->release_buffer(avctx, p);
168
169 p->reference = 0;
170 if(avctx->get_buffer(avctx, p) < 0){
171 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
172 return -1;
173 }
174 p->key_frame = 1;
175
176 switch(l->mode) {
177 case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
178 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
179 p->linesize[0], buf, buf_size, 1);
180 buf += decoded; buf_size -= decoded;
181 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
182 p->linesize[1], buf, buf_size, 1);
183 buf += decoded; buf_size -= decoded;
184 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
185 p->linesize[2], buf, buf_size, 1);
186 break;
187 case LOCO_CYV12: case LOCO_YV12:
188 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
189 p->linesize[0], buf, buf_size, 1);
190 buf += decoded; buf_size -= decoded;
191 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
192 p->linesize[2], buf, buf_size, 1);
193 buf += decoded; buf_size -= decoded;
194 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
195 p->linesize[1], buf, buf_size, 1);
196 break;
197 case LOCO_CRGB: case LOCO_RGB:
198 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
199 -p->linesize[0], buf, buf_size, 3);
200 buf += decoded; buf_size -= decoded;
201 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
202 -p->linesize[0], buf, buf_size, 3);
203 buf += decoded; buf_size -= decoded;
204 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
205 -p->linesize[0], buf, buf_size, 3);
206 break;
207 case LOCO_RGBA:
208 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
209 p->linesize[0], buf, buf_size, 4);
210 buf += decoded; buf_size -= decoded;
211 decoded = loco_decode_plane(l, p->data[0] + 1, avctx->width, avctx->height,
212 p->linesize[0], buf, buf_size, 4);
213 buf += decoded; buf_size -= decoded;
214 decoded = loco_decode_plane(l, p->data[0] + 2, avctx->width, avctx->height,
215 p->linesize[0], buf, buf_size, 4);
216 buf += decoded; buf_size -= decoded;
217 decoded = loco_decode_plane(l, p->data[0] + 3, avctx->width, avctx->height,
218 p->linesize[0], buf, buf_size, 4);
219 break;
220 }
221
222 *data_size = sizeof(AVFrame);
223 *(AVFrame*)data = l->pic;
224
225 return buf_size;
226}
227
228static int decode_init(AVCodecContext *avctx){
229 LOCOContext * const l = avctx->priv_data;
230 int version;
231
232 l->avctx = avctx;
233 if (avctx->extradata_size < 12) {
234 av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
235 avctx->extradata_size);
236 return -1;
237 }
238 version = LE_32(avctx->extradata);
239 switch(version) {
240 case 1:
241 l->lossy = 0;
242 break;
243 case 2:
244 l->lossy = LE_32(avctx->extradata + 8);
245 break;
246 default:
247 l->lossy = LE_32(avctx->extradata + 8);
248 av_log(avctx, AV_LOG_INFO, "This is LOCO codec version %i, please upload file for study\n", version);
249 }
250
251 l->mode = LE_32(avctx->extradata + 4);
252 switch(l->mode) {
253 case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
254 avctx->pix_fmt = PIX_FMT_YUV422P;
255 break;
256 case LOCO_CRGB: case LOCO_RGB:
257 avctx->pix_fmt = PIX_FMT_BGR24;
258 break;
259 case LOCO_CYV12: case LOCO_YV12:
260 avctx->pix_fmt = PIX_FMT_YUV420P;
261 break;
262 case LOCO_CRGBA: case LOCO_RGBA:
263 avctx->pix_fmt = PIX_FMT_RGBA32;
264 break;
265 default:
266 av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
267 return -1;
268 }
269 if(avctx->debug & FF_DEBUG_PICT_INFO)
270 av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
271
272 return 0;
273}
274
275AVCodec loco_decoder = {
276 "loco",
277 CODEC_TYPE_VIDEO,
278 CODEC_ID_LOCO,
279 sizeof(LOCOContext),
280 decode_init,
281 NULL,
282 NULL,
283 decode_frame,
284 CODEC_CAP_DR1,
285};
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