summaryrefslogtreecommitdiff
path: root/libavcodec/loco.c (plain)
blob: 9d0f144451f3c9bbfae68e059bdb6c5b27f84fcb
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
33enum 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
46typedef struct LOCOContext {
47 AVCodecContext *avctx;
48 int lossy;
49 enum LOCO_MODE mode;
50} LOCOContext;
51
52typedef struct RICEContext {
53 GetBitContext gb;
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
59static int loco_get_rice_param(RICEContext *r)
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
72static 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
83static inline int loco_get_rice(RICEContext *r)
84{
85 int v;
86 if (r->run > 0) { /* we have zero run */
87 r->run--;
88 loco_update_rice_param(r, 0);
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 */
117static 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
128static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
129 int stride, const uint8_t *buf, int buf_size, int step)
130{
131 RICEContext rc;
132 int val;
133 int ret;
134 int i, j;
135
136 if(buf_size<=0)
137 return -1;
138
139 if ((ret = init_get_bits8(&rc.gb, buf, buf_size)) < 0)
140 return ret;
141
142 rc.save = 0;
143 rc.run = 0;
144 rc.run2 = 0;
145 rc.lossy = l->lossy;
146
147 rc.sum = 8;
148 rc.count = 1;
149
150 /* restore top left pixel */
151 val = loco_get_rice(&rc);
152 data[0] = 128 + val;
153 /* restore top line */
154 for (i = 1; i < width; i++) {
155 val = loco_get_rice(&rc);
156 data[i * step] = data[i * step - step] + val;
157 }
158 data += stride;
159 for (j = 1; j < height; j++) {
160 /* restore left column */
161 val = loco_get_rice(&rc);
162 data[0] = data[-stride] + val;
163 /* restore all other pixels */
164 for (i = 1; i < width; i++) {
165 val = loco_get_rice(&rc);
166 data[i * step] = loco_predict(&data[i * step], stride, step) + val;
167 }
168 data += stride;
169 }
170
171 return (get_bits_count(&rc.gb) + 7) >> 3;
172}
173
174static void rotate_faulty_loco(uint8_t *data, int width, int height, int stride, int step)
175{
176 int y;
177
178 for (y=1; y<height; y++) {
179 if (width>=y) {
180 memmove(data + y*stride,
181 data + y*(stride + step),
182 step*(width-y));
183 if (y+1 < height)
184 memmove(data + y*stride + step*(width-y),
185 data + (y+1)*stride,
186 step*y);
187 }
188 }
189}
190
191static int decode_frame(AVCodecContext *avctx,
192 void *data, int *got_frame,
193 AVPacket *avpkt)
194{
195 LOCOContext * const l = avctx->priv_data;
196 const uint8_t *buf = avpkt->data;
197 int buf_size = avpkt->size;
198 AVFrame * const p = data;
199 int decoded, ret;
200
201 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
202 return ret;
203 p->key_frame = 1;
204
205#define ADVANCE_BY_DECODED do { \
206 if (decoded < 0 || decoded >= buf_size) goto buf_too_small; \
207 buf += decoded; buf_size -= decoded; \
208} while(0)
209 switch(l->mode) {
210 case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
211 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
212 p->linesize[0], buf, buf_size, 1);
213 ADVANCE_BY_DECODED;
214 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
215 p->linesize[1], buf, buf_size, 1);
216 ADVANCE_BY_DECODED;
217 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
218 p->linesize[2], buf, buf_size, 1);
219 break;
220 case LOCO_CYV12: case LOCO_YV12:
221 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
222 p->linesize[0], buf, buf_size, 1);
223 ADVANCE_BY_DECODED;
224 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
225 p->linesize[2], buf, buf_size, 1);
226 ADVANCE_BY_DECODED;
227 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
228 p->linesize[1], buf, buf_size, 1);
229 break;
230 case LOCO_CRGB: case LOCO_RGB:
231 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
232 -p->linesize[0], buf, buf_size, 3);
233 ADVANCE_BY_DECODED;
234 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
235 -p->linesize[0], buf, buf_size, 3);
236 ADVANCE_BY_DECODED;
237 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
238 -p->linesize[0], buf, buf_size, 3);
239 if (avctx->width & 1)
240 rotate_faulty_loco(p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height, -p->linesize[0], 3);
241 break;
242 case LOCO_CRGBA:
243 case LOCO_RGBA:
244 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
245 -p->linesize[0], buf, buf_size, 4);
246 ADVANCE_BY_DECODED;
247 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
248 -p->linesize[0], buf, buf_size, 4);
249 ADVANCE_BY_DECODED;
250 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
251 -p->linesize[0], buf, buf_size, 4);
252 ADVANCE_BY_DECODED;
253 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 3, avctx->width, avctx->height,
254 -p->linesize[0], buf, buf_size, 4);
255 break;
256 default:
257 av_assert0(0);
258 }
259
260 if (decoded < 0 || decoded > buf_size)
261 goto buf_too_small;
262 buf_size -= decoded;
263
264 *got_frame = 1;
265
266 return avpkt->size - buf_size;
267buf_too_small:
268 av_log(avctx, AV_LOG_ERROR, "Input data too small.\n");
269 return AVERROR(EINVAL);
270}
271
272static av_cold int decode_init(AVCodecContext *avctx)
273{
274 LOCOContext * const l = avctx->priv_data;
275 int version;
276
277 l->avctx = avctx;
278 if (avctx->extradata_size < 12) {
279 av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
280 avctx->extradata_size);
281 return AVERROR_INVALIDDATA;
282 }
283 version = AV_RL32(avctx->extradata);
284 switch (version) {
285 case 1:
286 l->lossy = 0;
287 break;
288 case 2:
289 l->lossy = AV_RL32(avctx->extradata + 8);
290 break;
291 default:
292 l->lossy = AV_RL32(avctx->extradata + 8);
293 avpriv_request_sample(avctx, "LOCO codec version %i", version);
294 }
295
296 l->mode = AV_RL32(avctx->extradata + 4);
297 switch (l->mode) {
298 case LOCO_CYUY2:
299 case LOCO_YUY2:
300 case LOCO_UYVY:
301 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
302 break;
303 case LOCO_CRGB:
304 case LOCO_RGB:
305 avctx->pix_fmt = AV_PIX_FMT_BGR24;
306 break;
307 case LOCO_CYV12:
308 case LOCO_YV12:
309 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
310 break;
311 case LOCO_CRGBA:
312 case LOCO_RGBA:
313 avctx->pix_fmt = AV_PIX_FMT_BGRA;
314 break;
315 default:
316 av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
317 return AVERROR_INVALIDDATA;
318 }
319 if (avctx->debug & FF_DEBUG_PICT_INFO)
320 av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
321
322 return 0;
323}
324
325AVCodec ff_loco_decoder = {
326 .name = "loco",
327 .long_name = NULL_IF_CONFIG_SMALL("LOCO"),
328 .type = AVMEDIA_TYPE_VIDEO,
329 .id = AV_CODEC_ID_LOCO,
330 .priv_data_size = sizeof(LOCOContext),
331 .init = decode_init,
332 .decode = decode_frame,
333 .capabilities = AV_CODEC_CAP_DR1,
334};
335
generated by cgit at 2024-05-17 05:14:36 (GMT)