FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavfilter/vf_blackframe.c
Date: 2024-04-20 14:10:07
Exec Total Coverage
Lines: 0 21 0.0%
Functions: 0 1 0.0%
Branches: 0 10 0.0%

Line Branch Exec Source
1 /*
2 * Copyright (c) 2010 Stefano Sabatini
3 * Copyright (c) 2006 Ivo van Poorten
4 * Copyright (c) 2006 Julian Hall
5 * Copyright (c) 2002-2003 Brian J. Murrell
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
22 */
23
24 /**
25 * @file
26 * Search for black frames to detect scene transitions.
27 * Ported from MPlayer libmpcodecs/vf_blackframe.c.
28 */
29
30 #include <stdio.h>
31 #include <inttypes.h>
32
33 #include "libavutil/internal.h"
34 #include "libavutil/opt.h"
35 #include "avfilter.h"
36 #include "internal.h"
37 #include "video.h"
38
39 typedef struct BlackFrameContext {
40 const AVClass *class;
41 int bamount; ///< black amount
42 int bthresh; ///< black threshold
43 unsigned int frame; ///< frame number
44 unsigned int nblack; ///< number of black pixels counted so far
45 unsigned int last_keyframe; ///< frame number of the last received key-frame
46 } BlackFrameContext;
47
48 static const enum AVPixelFormat pix_fmts[] = {
49 AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV420P, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NV12,
50 AV_PIX_FMT_NV21, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV411P,
51 AV_PIX_FMT_NONE
52 };
53
54 #define SET_META(key, format, value) \
55 snprintf(buf, sizeof(buf), format, value); \
56 av_dict_set(metadata, key, buf, 0)
57
58 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
59 {
60 AVFilterContext *ctx = inlink->dst;
61 BlackFrameContext *s = ctx->priv;
62 int x, i;
63 int pblack = 0;
64 uint8_t *p = frame->data[0];
65 AVDictionary **metadata;
66 char buf[32];
67
68 for (i = 0; i < frame->height; i++) {
69 for (x = 0; x < inlink->w; x++)
70 s->nblack += p[x] < s->bthresh;
71 p += frame->linesize[0];
72 }
73
74 if (frame->flags & AV_FRAME_FLAG_KEY)
75 s->last_keyframe = s->frame;
76
77 pblack = s->nblack * 100 / (inlink->w * inlink->h);
78 if (pblack >= s->bamount) {
79 metadata = &frame->metadata;
80
81 av_log(ctx, AV_LOG_INFO, "frame:%u pblack:%u pts:%"PRId64" t:%f "
82 "type:%c last_keyframe:%d\n",
83 s->frame, pblack, frame->pts,
84 frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base),
85 av_get_picture_type_char(frame->pict_type), s->last_keyframe);
86
87 SET_META("lavfi.blackframe.pblack", "%u", pblack);
88 }
89
90 s->frame++;
91 s->nblack = 0;
92 return ff_filter_frame(inlink->dst->outputs[0], frame);
93 }
94
95 #define OFFSET(x) offsetof(BlackFrameContext, x)
96 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
97 static const AVOption blackframe_options[] = {
98 { "amount", "percentage of the pixels that have to be below the threshold "
99 "for the frame to be considered black", OFFSET(bamount), AV_OPT_TYPE_INT, { .i64 = 98 }, 0, 100, FLAGS },
100 { "threshold", "threshold below which a pixel value is considered black",
101 OFFSET(bthresh), AV_OPT_TYPE_INT, { .i64 = 32 }, 0, 255, FLAGS },
102 { "thresh", "threshold below which a pixel value is considered black",
103 OFFSET(bthresh), AV_OPT_TYPE_INT, { .i64 = 32 }, 0, 255, FLAGS },
104 { NULL }
105 };
106
107 AVFILTER_DEFINE_CLASS(blackframe);
108
109 static const AVFilterPad avfilter_vf_blackframe_inputs[] = {
110 {
111 .name = "default",
112 .type = AVMEDIA_TYPE_VIDEO,
113 .filter_frame = filter_frame,
114 },
115 };
116
117 const AVFilter ff_vf_blackframe = {
118 .name = "blackframe",
119 .description = NULL_IF_CONFIG_SMALL("Detect frames that are (almost) black."),
120 .priv_size = sizeof(BlackFrameContext),
121 .priv_class = &blackframe_class,
122 .flags = AVFILTER_FLAG_METADATA_ONLY,
123 FILTER_INPUTS(avfilter_vf_blackframe_inputs),
124 FILTER_OUTPUTS(ff_video_default_filterpad),
125 FILTER_PIXFMTS_ARRAY(pix_fmts),
126 };
127