FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavcodec/loco.c
Date: 2026-01-23 19:11:46
Exec Total Coverage
Lines: 119 188 63.3%
Functions: 7 8 87.5%
Branches: 52 111 46.8%
Line Branch Exec Source
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 "codec_internal.h"
29 #include "decode.h"
30 #include "get_bits.h"
31 #include "golomb.h"
32 #include "mathops.h"
33
34 enum LOCO_MODE {
35 LOCO_UNKN = 0,
36 LOCO_CYUY2 = -1,
37 LOCO_CRGB = -2,
38 LOCO_CRGBA = -3,
39 LOCO_CYV12 = -4,
40 LOCO_YUY2 = 1,
41 LOCO_UYVY = 2,
42 LOCO_RGB = 3,
43 LOCO_RGBA = 4,
44 LOCO_YV12 = 5,
45 };
46
47 typedef struct LOCOContext {
48 AVCodecContext *avctx;
49 int lossy;
50 enum LOCO_MODE mode;
51 } LOCOContext;
52
53 typedef struct RICEContext {
54 GetBitContext gb;
55 int save, run, run2; /* internal rice decoder state */
56 int sum, count; /* sum and count for getting rice parameter */
57 int lossy;
58 } RICEContext;
59
60 500785 static int loco_get_rice_param(RICEContext *r)
61 {
62 500785 int cnt = 0;
63 500785 int val = r->count;
64
65
3/4
✓ Branch 0 taken 1888415 times.
✓ Branch 1 taken 500785 times.
✓ Branch 2 taken 1888415 times.
✗ Branch 3 not taken.
 2389200 while (r->sum > val && cnt < 9) {
66 1888415 val <<= 1;
67 1888415 cnt++;
68 }
69
70 500785 return cnt;
71 }
72
73 505344 static inline void loco_update_rice_param(RICEContext *r, int val)
74 {
75 505344 r->sum += val;
76 505344 r->count++;
77
78
2/2
✓ Branch 0 taken 63144 times.
✓ Branch 1 taken 442200 times.
 505344 if (r->count == 16) {
79 63144 r->sum >>= 1;
80 63144 r->count >>= 1;
81 }
82 505344 }
83
84 505344 static inline int loco_get_rice(RICEContext *r)
85 {
86 unsigned v;
87
2/2
✓ Branch 0 taken 4559 times.
✓ Branch 1 taken 500785 times.
 505344 if (r->run > 0) { /* we have zero run */
88 4559 r->run--;
89 4559 loco_update_rice_param(r, 0);
90 4559 return 0;
91 }
92
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 500785 times.
 500785 if (get_bits_left(&r->gb) < 1)
93 ✗ return INT_MIN;
94 500785 v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
95
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 500785 times.
 500785 if (v == -1)
96 ✗ return INT_MIN;
97 500785 loco_update_rice_param(r, (v + 1) >> 1);
98
2/2
✓ Branch 0 taken 49474 times.
✓ Branch 1 taken 451311 times.
 500785 if (!v) {
99
2/2
✓ Branch 0 taken 2574 times.
✓ Branch 1 taken 46900 times.
 49474 if (r->save >= 0) {
100 2574 int run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
101
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2574 times.
 2574 if (run == -1)
102 ✗ return INT_MIN;
103 2574 r->run = run;
104
2/2
✓ Branch 0 taken 901 times.
✓ Branch 1 taken 1673 times.
 2574 if (r->run > 1)
105 901 r->save += r->run + 1;
106 else
107 1673 r->save -= 3;
108 } else
109 46900 r->run2++;
110 } else {
111 451311 v = ((v >> 1) + r->lossy) ^ -(v & 1);
112
2/2
✓ Branch 0 taken 27417 times.
✓ Branch 1 taken 423894 times.
 451311 if (r->run2 > 0) {
113
2/2
✓ Branch 0 taken 3721 times.
✓ Branch 1 taken 23696 times.
 27417 if (r->run2 > 2)
114 3721 r->save += r->run2;
115 else
116 23696 r->save -= 3;
117 27417 r->run2 = 0;
118 }
119 }
120
121 500785 return v;
122 }
123
124 /* LOCO main predictor - LOCO-I/JPEG-LS predictor */
125 498348 static inline int loco_predict(uint8_t* data, int stride)
126 {
127 int a, b, c;
128
129 498348 a = data[-stride];
130 498348 b = data[-1];
131 498348 c = data[-stride - 1];
132
133 498348 return mid_pred(a, a + b - c, b);
134 }
135
136 24 static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
137 int stride, const uint8_t *buf, int buf_size)
138 {
139 RICEContext rc;
140 unsigned val;
141 int ret;
142 int i, j;
143
144
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 24 times.
 24 if(buf_size<=0)
145 ✗ return -1;
146
147
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 24 times.
 24 if ((ret = init_get_bits8(&rc.gb, buf, buf_size)) < 0)
148 ✗ return ret;
149
150 24 rc.save = 0;
151 24 rc.run = 0;
152 24 rc.run2 = 0;
153 24 rc.lossy = l->lossy;
154
155 24 rc.sum = 8;
156 24 rc.count = 1;
157
158 /* restore top left pixel */
159 24 val = loco_get_rice(&rc);
160
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 24 times.
 24 if (val == INT_MIN)
161 ✗ return AVERROR_INVALIDDATA;
162 24 data[0] = 128 + val;
163 /* restore top line */
164
2/2
✓ Branch 0 taken 3924 times.
✓ Branch 1 taken 24 times.
 3948 for (i = 1; i < width; i++) {
165 3924 val = loco_get_rice(&rc);
166
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 3924 times.
 3924 if (val == INT_MIN)
167 ✗ return AVERROR_INVALIDDATA;
168 3924 data[i] = data[i - 1] + val;
169 }
170 24 data += stride;
171
2/2
✓ Branch 0 taken 3048 times.
✓ Branch 1 taken 24 times.
 3072 for (j = 1; j < height; j++) {
172 /* restore left column */
173 3048 val = loco_get_rice(&rc);
174
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 3048 times.
 3048 if (val == INT_MIN)
175 ✗ return AVERROR_INVALIDDATA;
176 3048 data[0] = data[-stride] + val;
177 /* restore all other pixels */
178
2/2
✓ Branch 0 taken 498348 times.
✓ Branch 1 taken 3048 times.
 501396 for (i = 1; i < width; i++) {
179 498348 val = loco_get_rice(&rc);
180
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 498348 times.
 498348 if (val == INT_MIN)
181 ✗ return -1;
182 498348 data[i] = loco_predict(&data[i], stride) + val;
183 }
184 3048 data += stride;
185 }
186
187 24 return (get_bits_count(&rc.gb) + 7) >> 3;
188 }
189
190 ✗ static void rotate_faulty_loco(uint8_t *data, int width, int height, int stride)
191 {
192 int y;
193
194 ✗ for (y=1; y<height; y++) {
195 ✗ if (width>=y) {
196 ✗ memmove(data + y*stride,
197 ✗ data + y*(stride + 1),
198 ✗ (width-y));
199 ✗ if (y+1 < height)
200 ✗ memmove(data + y*stride + (width-y),
201 ✗ data + (y+1)*stride, y);
202 }
203 }
204 ✗ }
205
206 8 static int decode_frame(AVCodecContext *avctx, AVFrame *p,
207 int *got_frame, AVPacket *avpkt)
208 {
209 8 LOCOContext * const l = avctx->priv_data;
210 8 const uint8_t *buf = avpkt->data;
211 8 int buf_size = avpkt->size;
212 int decoded, ret;
213
214
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 8 times.
 8 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
215 ✗ return ret;
216
217 #define ADVANCE_BY_DECODED do { \
218 if (decoded < 0 || decoded >= buf_size) goto buf_too_small; \
219 buf += decoded; buf_size -= decoded; \
220 } while(0)
221
2/5
✓ Branch 0 taken 3 times.
✗ Branch 1 not taken.
✓ Branch 2 taken 5 times.
✗ Branch 3 not taken.
✗ Branch 4 not taken.
 8 switch(l->mode) {
222 3 case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
223 3 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
224 p->linesize[0], buf, buf_size);
225
2/4
✓ Branch 0 taken 3 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 3 times.
 3 ADVANCE_BY_DECODED;
226 3 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
227 p->linesize[1], buf, buf_size);
228
2/4
✓ Branch 0 taken 3 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 3 times.
 3 ADVANCE_BY_DECODED;
229 3 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
230 p->linesize[2], buf, buf_size);
231 3 break;
232 ✗ case LOCO_CYV12: case LOCO_YV12:
233 ✗ decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
234 p->linesize[0], buf, buf_size);
235 ✗ ADVANCE_BY_DECODED;
236 ✗ decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
237 p->linesize[2], buf, buf_size);
238 ✗ ADVANCE_BY_DECODED;
239 ✗ decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
240 p->linesize[1], buf, buf_size);
241 ✗ break;
242 5 case LOCO_CRGB: case LOCO_RGB:
243 5 decoded = loco_decode_plane(l, p->data[1] + p->linesize[1]*(avctx->height-1), avctx->width, avctx->height,
244 5 -p->linesize[1], buf, buf_size);
245
2/4
✓ Branch 0 taken 5 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 5 times.
 5 ADVANCE_BY_DECODED;
246 5 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
247 5 -p->linesize[0], buf, buf_size);
248
2/4
✓ Branch 0 taken 5 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 5 times.
 5 ADVANCE_BY_DECODED;
249 5 decoded = loco_decode_plane(l, p->data[2] + p->linesize[2]*(avctx->height-1), avctx->width, avctx->height,
250 5 -p->linesize[2], buf, buf_size);
251
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 5 times.
 5 if (avctx->width & 1) {
252 ✗ rotate_faulty_loco(p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height, -p->linesize[0]);
253 ✗ rotate_faulty_loco(p->data[1] + p->linesize[1]*(avctx->height-1), avctx->width, avctx->height, -p->linesize[1]);
254 ✗ rotate_faulty_loco(p->data[2] + p->linesize[2]*(avctx->height-1), avctx->width, avctx->height, -p->linesize[2]);
255 }
256 5 break;
257 ✗ case LOCO_CRGBA:
258 case LOCO_RGBA:
259 ✗ decoded = loco_decode_plane(l, p->data[1] + p->linesize[1]*(avctx->height-1), avctx->width, avctx->height,
260 ✗ -p->linesize[1], buf, buf_size);
261 ✗ ADVANCE_BY_DECODED;
262 ✗ decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
263 ✗ -p->linesize[0], buf, buf_size);
264 ✗ ADVANCE_BY_DECODED;
265 ✗ decoded = loco_decode_plane(l, p->data[2] + p->linesize[2]*(avctx->height-1), avctx->width, avctx->height,
266 ✗ -p->linesize[2], buf, buf_size);
267 ✗ ADVANCE_BY_DECODED;
268 ✗ decoded = loco_decode_plane(l, p->data[3] + p->linesize[3]*(avctx->height-1), avctx->width, avctx->height,
269 ✗ -p->linesize[3], buf, buf_size);
270 ✗ break;
271 ✗ default:
272 ✗ av_assert0(0);
273 }
274
275
2/4
✓ Branch 0 taken 8 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 8 times.
 8 if (decoded < 0 || decoded > buf_size)
276 ✗ goto buf_too_small;
277 8 buf_size -= decoded;
278
279 8 *got_frame = 1;
280
281 8 return avpkt->size - buf_size;
282 ✗ buf_too_small:
283 ✗ av_log(avctx, AV_LOG_ERROR, "Input data too small.\n");
284 ✗ return AVERROR(EINVAL);
285 }
286
287 4 static av_cold int decode_init(AVCodecContext *avctx)
288 {
289 4 LOCOContext * const l = avctx->priv_data;
290 int version;
291
292 4 l->avctx = avctx;
293
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 4 times.
 4 if (avctx->extradata_size < 12) {
294 ✗ av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
295 avctx->extradata_size);
296 ✗ return AVERROR_INVALIDDATA;
297 }
298 4 version = AV_RL32(avctx->extradata);
299
1/3
✗ Branch 0 not taken.
✓ Branch 1 taken 4 times.
✗ Branch 2 not taken.
 4 switch (version) {
300 ✗ case 1:
301 ✗ l->lossy = 0;
302 ✗ break;
303 4 case 2:
304 4 l->lossy = AV_RL32(avctx->extradata + 8);
305 4 break;
306 ✗ default:
307 ✗ l->lossy = AV_RL32(avctx->extradata + 8);
308 ✗ avpriv_request_sample(avctx, "LOCO codec version %i", version);
309 }
310
311
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 4 times.
 4 if (l->lossy > 65536U) {
312 ✗ av_log(avctx, AV_LOG_ERROR, "lossy %i is too large\n", l->lossy);
313 ✗ return AVERROR_INVALIDDATA;
314 }
315
316 4 l->mode = AV_RL32(avctx->extradata + 4);
317
2/5
✓ Branch 0 taken 2 times.
✓ Branch 1 taken 2 times.
✗ Branch 2 not taken.
✗ Branch 3 not taken.
✗ Branch 4 not taken.
 4 switch (l->mode) {
318 2 case LOCO_CYUY2:
319 case LOCO_YUY2:
320 case LOCO_UYVY:
321 2 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
322 2 break;
323 2 case LOCO_CRGB:
324 case LOCO_RGB:
325 2 avctx->pix_fmt = AV_PIX_FMT_GBRP;
326 2 break;
327 ✗ case LOCO_CYV12:
328 case LOCO_YV12:
329 ✗ avctx->pix_fmt = AV_PIX_FMT_YUV420P;
330 ✗ break;
331 ✗ case LOCO_CRGBA:
332 case LOCO_RGBA:
333 ✗ avctx->pix_fmt = AV_PIX_FMT_GBRAP;
334 ✗ break;
335 ✗ default:
336 ✗ av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
337 ✗ return AVERROR_INVALIDDATA;
338 }
339
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 4 times.
 4 if (avctx->debug & FF_DEBUG_PICT_INFO)
340 ✗ av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
341
342 4 return 0;
343 }
344
345 const FFCodec ff_loco_decoder = {
346 .p.name = "loco",
347 CODEC_LONG_NAME("LOCO"),
348 .p.type = AVMEDIA_TYPE_VIDEO,
349 .p.id = AV_CODEC_ID_LOCO,
350 .priv_data_size = sizeof(LOCOContext),
351 .init = decode_init,
352 FF_CODEC_DECODE_CB(decode_frame),
353 .p.capabilities = AV_CODEC_CAP_DR1,
354 };
355