a837e4b9bd147700997a906b6df6796f498e30a6
[libav.git] / libavcodec / loco.c
1 /*
2 * LOCO codec
3 * Copyright (c) 2005 Konstantin Shishkov
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; 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 {LOCO_UNKN=0, LOCO_CYUY2=-1, LOCO_CRGB=-2, LOCO_CRGBA=-3, LOCO_CYV12=-4,
34 LOCO_YUY2=1, LOCO_UYVY=2, LOCO_RGB=3, LOCO_RGBA=4, LOCO_YV12=5};
35
36 typedef struct LOCOContext{
37 AVCodecContext *avctx;
38 AVFrame pic;
39 int lossy;
40 int mode;
41 } LOCOContext;
42
43 typedef struct RICEContext{
44 GetBitContext gb;
45 int save, run, run2; /* internal rice decoder state */
46 int sum, count; /* sum and count for getting rice parameter */
47 int lossy;
48 }RICEContext;
49
50 static int loco_get_rice_param(RICEContext *r)
51 {
52 int cnt = 0;
53 int val = r->count;
54
55 while(r->sum > val && cnt < 9) {
56 val <<= 1;
57 cnt++;
58 }
59
60 return cnt;
61 }
62
63 static inline void loco_update_rice_param(RICEContext *r, int val)
64 {
65 r->sum += val;
66 r->count++;
67
68 if(r->count == 16) {
69 r->sum >>= 1;
70 r->count >>= 1;
71 }
72 }
73
74 static inline int loco_get_rice(RICEContext *r)
75 {
76 int v;
77 if (r->run > 0) { /* we have zero run */
78 r->run--;
79 loco_update_rice_param(r, 0);
80 return 0;
81 }
82 v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
83 loco_update_rice_param(r, (v+1)>>1);
84 if (!v) {
85 if (r->save >= 0) {
86 r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
87 if(r->run > 1)
88 r->save += r->run + 1;
89 else
90 r->save -= 3;
91 }
92 else
93 r->run2++;
94 } else {
95 v = ((v>>1) + r->lossy) ^ -(v&1);
96 if (r->run2 > 0) {
97 if (r->run2 > 2)
98 r->save += r->run2;
99 else
100 r->save -= 3;
101 r->run2 = 0;
102 }
103 }
104
105 return v;
106 }
107
108 /* LOCO main predictor - LOCO-I/JPEG-LS predictor */
109 static inline int loco_predict(uint8_t* data, int stride, int step)
110 {
111 int a, b, c;
112
113 a = data[-stride];
114 b = data[-step];
115 c = data[-stride - step];
116
117 return mid_pred(a, a + b - c, b);
118 }
119
120 static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
121 int stride, const uint8_t *buf, int buf_size, int step)
122 {
123 RICEContext rc;
124 int val;
125 int i, j;
126
127 init_get_bits(&rc.gb, buf, buf_size*8);
128 rc.save = 0;
129 rc.run = 0;
130 rc.run2 = 0;
131 rc.lossy = l->lossy;
132
133 rc.sum = 8;
134 rc.count = 1;
135
136 /* restore top left pixel */
137 val = loco_get_rice(&rc);
138 data[0] = 128 + val;
139 /* restore top line */
140 for (i = 1; i < width; i++) {
141 val = loco_get_rice(&rc);
142 data[i * step] = data[i * step - step] + val;
143 }
144 data += stride;
145 for (j = 1; j < height; j++) {
146 /* restore left column */
147 val = loco_get_rice(&rc);
148 data[0] = data[-stride] + val;
149 /* restore all other pixels */
150 for (i = 1; i < width; i++) {
151 val = loco_get_rice(&rc);
152 data[i * step] = loco_predict(&data[i * step], stride, step) + val;
153 }
154 data += stride;
155 }
156
157 return (get_bits_count(&rc.gb) + 7) >> 3;
158 }
159
160 static int decode_frame(AVCodecContext *avctx,
161 void *data, int *data_size,
162 AVPacket *avpkt)
163 {
164 const uint8_t *buf = avpkt->data;
165 int buf_size = avpkt->size;
166 LOCOContext * const l = avctx->priv_data;
167 AVFrame * const p = &l->pic;
168 int decoded;
169
170 if(p->data[0])
171 avctx->release_buffer(avctx, p);
172
173 p->reference = 0;
174 if(ff_get_buffer(avctx, p) < 0){
175 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
176 return -1;
177 }
178 p->key_frame = 1;
179
180 switch(l->mode) {
181 case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
182 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
183 p->linesize[0], buf, buf_size, 1);
184 buf += decoded; buf_size -= decoded;
185 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
186 p->linesize[1], buf, buf_size, 1);
187 buf += decoded; buf_size -= decoded;
188 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
189 p->linesize[2], buf, buf_size, 1);
190 break;
191 case LOCO_CYV12: case LOCO_YV12:
192 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
193 p->linesize[0], buf, buf_size, 1);
194 buf += decoded; buf_size -= decoded;
195 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
196 p->linesize[2], buf, buf_size, 1);
197 buf += decoded; buf_size -= decoded;
198 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
199 p->linesize[1], buf, buf_size, 1);
200 break;
201 case LOCO_CRGB: case LOCO_RGB:
202 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
203 -p->linesize[0], buf, buf_size, 3);
204 buf += decoded; buf_size -= decoded;
205 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
206 -p->linesize[0], buf, buf_size, 3);
207 buf += decoded; buf_size -= decoded;
208 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
209 -p->linesize[0], buf, buf_size, 3);
210 break;
211 case LOCO_RGBA:
212 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
213 p->linesize[0], buf, buf_size, 4);
214 buf += decoded; buf_size -= decoded;
215 decoded = loco_decode_plane(l, p->data[0] + 1, avctx->width, avctx->height,
216 p->linesize[0], buf, buf_size, 4);
217 buf += decoded; buf_size -= decoded;
218 decoded = loco_decode_plane(l, p->data[0] + 2, avctx->width, avctx->height,
219 p->linesize[0], buf, buf_size, 4);
220 buf += decoded; buf_size -= decoded;
221 decoded = loco_decode_plane(l, p->data[0] + 3, avctx->width, avctx->height,
222 p->linesize[0], buf, buf_size, 4);
223 break;
224 }
225
226 *data_size = sizeof(AVFrame);
227 *(AVFrame*)data = l->pic;
228
229 return buf_size;
230 }
231
232 static av_cold int decode_init(AVCodecContext *avctx){
233 LOCOContext * const l = avctx->priv_data;
234 int version;
235
236 l->avctx = avctx;
237 if (avctx->extradata_size < 12) {
238 av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
239 avctx->extradata_size);
240 return -1;
241 }
242 version = AV_RL32(avctx->extradata);
243 switch(version) {
244 case 1:
245 l->lossy = 0;
246 break;
247 case 2:
248 l->lossy = AV_RL32(avctx->extradata + 8);
249 break;
250 default:
251 l->lossy = AV_RL32(avctx->extradata + 8);
252 av_log_ask_for_sample(avctx, "This is LOCO codec version %i.\n", version);
253 }
254
255 l->mode = AV_RL32(avctx->extradata + 4);
256 switch(l->mode) {
257 case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
258 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
259 break;
260 case LOCO_CRGB: case LOCO_RGB:
261 avctx->pix_fmt = AV_PIX_FMT_BGR24;
262 break;
263 case LOCO_CYV12: case LOCO_YV12:
264 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
265 break;
266 case LOCO_CRGBA: case LOCO_RGBA:
267 avctx->pix_fmt = AV_PIX_FMT_RGB32;
268 break;
269 default:
270 av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
271 return -1;
272 }
273 if(avctx->debug & FF_DEBUG_PICT_INFO)
274 av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
275
276 return 0;
277 }
278
279 static av_cold int decode_end(AVCodecContext *avctx){
280 LOCOContext * const l = avctx->priv_data;
281 AVFrame *pic = &l->pic;
282
283 if (pic->data[0])
284 avctx->release_buffer(avctx, pic);
285
286 return 0;
287 }
288
289 AVCodec ff_loco_decoder = {
290 .name = "loco",
291 .type = AVMEDIA_TYPE_VIDEO,
292 .id = AV_CODEC_ID_LOCO,
293 .priv_data_size = sizeof(LOCOContext),
294 .init = decode_init,
295 .close = decode_end,
296 .decode = decode_frame,
297 .capabilities = CODEC_CAP_DR1,
298 .long_name = NULL_IF_CONFIG_SMALL("LOCO"),
299 };