FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavfilter/vf_entropy.c
Date: 2026-04-21 03:24:50
Exec Total Coverage
Lines: 0 59 0.0%
Functions: 0 3 0.0%
Branches: 0 40 0.0%
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1 /*
2 * Copyright (c) 2017 Paul B Mahol
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include "libavutil/mem.h"
22 #include "libavutil/opt.h"
23 #include "libavutil/pixdesc.h"
24 #include "avfilter.h"
25 #include "drawutils.h"
26 #include "filters.h"
27 #include "video.h"
28
29 typedef struct EntropyContext {
30 const AVClass *class;
31
32 int mode;
33
34 int nb_planes;
35 int planeheight[4];
36 int planewidth[4];
37 int depth;
38 int is_rgb;
39 uint8_t rgba_map[4];
40 char planenames[4];
41 int64_t *histogram;
42 } EntropyContext;
43
44 #define OFFSET(x) offsetof(EntropyContext, x)
45 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
46 static const AVOption entropy_options[] = {
47 { "mode", "set kind of histogram entropy measurement", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS, .unit = "mode" },
48 { "normal", NULL, 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, .unit = "mode" },
49 { "diff", NULL, 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, .unit = "mode" },
50 { NULL }
51 };
52
53 AVFILTER_DEFINE_CLASS(entropy);
54
55 static const enum AVPixelFormat pixfmts[] = {
56 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P,
57 AV_PIX_FMT_YUV440P,
58 AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ411P,
59 AV_PIX_FMT_YUVJ440P,
60 AV_PIX_FMT_YUV444P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV420P9,
61 AV_PIX_FMT_YUV444P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV420P10,
62 AV_PIX_FMT_YUV440P10,
63 AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV420P12,
64 AV_PIX_FMT_YUV440P12,
65 AV_PIX_FMT_YUV444P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV420P14,
66 AV_PIX_FMT_YUV444P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV420P16,
67 AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10,
68 AV_PIX_FMT_GBRP12, AV_PIX_FMT_GBRP14, AV_PIX_FMT_GBRP16,
69 AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY9, AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12, AV_PIX_FMT_GRAY14, AV_PIX_FMT_GRAY16,
70 AV_PIX_FMT_NONE
71 };
72
73 ✗ static int config_input(AVFilterLink *inlink)
74 {
75 ✗ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
76 ✗ AVFilterContext *ctx = inlink->dst;
77 ✗ EntropyContext *s = ctx->priv;
78
79 ✗ s->nb_planes = desc->nb_components;
80
81 ✗ s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
82 ✗ s->planeheight[0] = s->planeheight[3] = inlink->h;
83 ✗ s->planewidth[1] = s->planewidth[2] = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
84 ✗ s->planewidth[0] = s->planewidth[3] = inlink->w;
85
86 ✗ s->depth = desc->comp[0].depth;
87 ✗ s->is_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
88
89 ✗ s->planenames[0] = s->is_rgb ? 'R' : 'Y';
90 ✗ s->planenames[1] = s->is_rgb ? 'G' : 'U';
91 ✗ s->planenames[2] = s->is_rgb ? 'B' : 'V';
92 ✗ s->planenames[3] = 'A';
93
94 ✗ s->histogram = av_malloc_array(1 << s->depth, sizeof(*s->histogram));
95 ✗ if (!s->histogram)
96 ✗ return AVERROR(ENOMEM);
97
98 ✗ return 0;
99 }
100
101 ✗ static int filter_frame(AVFilterLink *inlink, AVFrame *in)
102 {
103 ✗ AVFilterContext *ctx = inlink->dst;
104 ✗ AVFilterLink *outlink = ctx->outputs[0];
105 ✗ EntropyContext *s = ctx->priv;
106 int plane, y, x;
107
108 ✗ for (plane = 0; plane < s->nb_planes; plane++) {
109 ✗ int cidx = s->is_rgb ? s->rgba_map[plane] : plane;
110 ✗ const uint8_t *src8 = in->data[plane];
111 ✗ const uint16_t *src16 = (const uint16_t *)in->data[plane];
112 ✗ float total = s->planewidth[plane] * s->planeheight[plane];
113 ✗ float entropy = 0;
114 char metabuf[128];
115 char key[128];
116
117 ✗ memset(s->histogram, 0, (1 << s->depth) * sizeof(*s->histogram));
118
119 ✗ if (s->depth <= 8) {
120 ✗ for (y = 0; y < s->planeheight[plane]; y++) {
121 ✗ for (x = 0; x < s->planewidth[plane]; x++) {
122 ✗ s->histogram[src8[x]]++;
123 }
124
125 ✗ src8 += in->linesize[plane];
126 }
127 } else {
128 ✗ for (y = 0; y < s->planeheight[plane]; y++) {
129 ✗ for (x = 0; x < s->planewidth[plane]; x++) {
130 ✗ s->histogram[src16[x]]++;
131 }
132
133 ✗ src16 += in->linesize[plane] / 2;
134 }
135 }
136
137 ✗ for (y = 0; y < 1 << s->depth; y++) {
138 ✗ if (s->mode == 0) {
139 ✗ if (s->histogram[y]) {
140 ✗ float p = s->histogram[y] / total;
141 ✗ entropy += -log2(p) * p;
142 }
143 ✗ } else if (s->mode == 1) {
144 ✗ if (y && (s->histogram[y] - s->histogram[y - 1]) != 0) {
145 ✗ float p = FFABS(s->histogram[y] - s->histogram[y - 1]) / total;
146 ✗ entropy += -log2(p) * p;
147 }
148 }
149 }
150
151 ✗ snprintf(key, sizeof(key), "lavfi.entropy.entropy.%s.%c", s->mode ? "diff" : "normal", s->planenames[cidx]);
152 ✗ snprintf(metabuf, sizeof(metabuf), "%f", entropy);
153 ✗ av_dict_set(&in->metadata, key, metabuf, 0);
154 ✗ snprintf(key, sizeof(key), "lavfi.entropy.normalized_entropy.%s.%c", s->mode ? "diff" : "normal", s->planenames[cidx]);
155 ✗ snprintf(metabuf, sizeof(metabuf), "%f", entropy / log2(1 << s->depth));
156 ✗ av_dict_set(&in->metadata, key, metabuf, 0);
157 }
158
159 ✗ return ff_filter_frame(outlink, in);
160 }
161
162 ✗ static av_cold void uninit(AVFilterContext *ctx)
163 {
164 ✗ EntropyContext *s = ctx->priv;
165
166 ✗ av_freep(&s->histogram);
167 ✗ }
168
169 static const AVFilterPad inputs[] = {
170 {
171 .name = "default",
172 .type = AVMEDIA_TYPE_VIDEO,
173 .filter_frame = filter_frame,
174 .config_props = config_input,
175 },
176 };
177
178 const FFFilter ff_vf_entropy = {
179 .p.name = "entropy",
180 .p.description = NULL_IF_CONFIG_SMALL("Measure video frames entropy."),
181 .p.priv_class = &entropy_class,
182 .p.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_METADATA_ONLY,
183 .priv_size = sizeof(EntropyContext),
184 .uninit = uninit,
185 FILTER_INPUTS(inputs),
186 FILTER_OUTPUTS(ff_video_default_filterpad),
187 FILTER_PIXFMTS_ARRAY(pixfmts),
188 };
189