FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavfilter/vf_random.c
Date: 2022-12-09 07:38:14
Exec Total Coverage
Lines: 0 41 0.0%
Functions: 0 4 0.0%
Branches: 0 14 0.0%

Line Branch Exec Source
1 /*
2 * Copyright (c) 2015 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/lfg.h"
22 #include "libavutil/opt.h"
23 #include "libavutil/random_seed.h"
24 #include "avfilter.h"
25 #include "formats.h"
26 #include "internal.h"
27 #include "video.h"
28
29 #define MAX_FRAMES 512
30
31 typedef struct RandomContext {
32 const AVClass *class;
33
34 AVLFG lfg;
35 int nb_frames;
36 int64_t random_seed;
37 int nb_frames_filled;
38 AVFrame *frames[MAX_FRAMES];
39 int64_t pts[MAX_FRAMES];
40 int flush_idx;
41 } RandomContext;
42
43 #define OFFSET(x) offsetof(RandomContext, x)
44 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
45
46 static const AVOption random_options[] = {
47 { "frames", "set number of frames in cache", OFFSET(nb_frames), AV_OPT_TYPE_INT, {.i64=30}, 2, MAX_FRAMES, FLAGS },
48 { "seed", "set the seed", OFFSET(random_seed), AV_OPT_TYPE_INT64, {.i64=-1}, -1, UINT32_MAX, FLAGS },
49 { NULL }
50 };
51
52 AVFILTER_DEFINE_CLASS(random);
53
54 static av_cold int init(AVFilterContext *ctx)
55 {
56 RandomContext *s = ctx->priv;
57 uint32_t seed;
58
59 if (s->random_seed < 0)
60 s->random_seed = av_get_random_seed();
61 seed = s->random_seed;
62 av_lfg_init(&s->lfg, seed);
63
64 return 0;
65 }
66
67 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
68 {
69 AVFilterContext *ctx = inlink->dst;
70 RandomContext *s = ctx->priv;
71 AVFilterLink *outlink = ctx->outputs[0];
72 AVFrame *out;
73 int idx;
74
75 if (s->nb_frames_filled < s->nb_frames) {
76 s->frames[s->nb_frames_filled] = in;
77 s->pts[s->nb_frames_filled++] = in->pts;
78 return 0;
79 }
80
81 idx = av_lfg_get(&s->lfg) % s->nb_frames;
82
83 out = s->frames[idx];
84 out->pts = s->pts[0];
85 memmove(&s->pts[0], &s->pts[1], (s->nb_frames - 1) * sizeof(s->pts[0]));
86 s->frames[idx] = in;
87 s->pts[s->nb_frames - 1] = in->pts;
88
89 return ff_filter_frame(outlink, out);
90 }
91
92 static int request_frame(AVFilterLink *outlink)
93 {
94 AVFilterContext *ctx = outlink->src;
95 RandomContext *s = ctx->priv;
96 int ret;
97
98 ret = ff_request_frame(ctx->inputs[0]);
99
100 next:
101 if (ret == AVERROR_EOF && !ctx->is_disabled && s->nb_frames > 0) {
102 AVFrame *out = s->frames[s->nb_frames - 1];
103 if (!out) {
104 s->nb_frames--;
105 goto next;
106 }
107 out->pts = s->pts[s->flush_idx++];
108 ret = ff_filter_frame(outlink, out);
109 s->frames[s->nb_frames - 1] = NULL;
110 s->nb_frames--;
111 }
112
113 return ret;
114 }
115
116 static av_cold void uninit(AVFilterContext *ctx)
117 {
118 RandomContext *s = ctx->priv;
119
120 for (int i = 0; i < s->nb_frames; i++)
121 av_frame_free(&s->frames[i]);
122 }
123
124 static const AVFilterPad random_inputs[] = {
125 {
126 .name = "default",
127 .type = AVMEDIA_TYPE_VIDEO,
128 .filter_frame = filter_frame,
129 },
130 };
131
132 static const AVFilterPad random_outputs[] = {
133 {
134 .name = "default",
135 .type = AVMEDIA_TYPE_VIDEO,
136 .request_frame = request_frame,
137 },
138 };
139
140 const AVFilter ff_vf_random = {
141 .name = "random",
142 .description = NULL_IF_CONFIG_SMALL("Return random frames."),
143 .priv_size = sizeof(RandomContext),
144 .priv_class = &random_class,
145 .init = init,
146 .uninit = uninit,
147 FILTER_INPUTS(random_inputs),
148 FILTER_OUTPUTS(random_outputs),
149 };
150