[FFmpeg-cvslog] avfilter/vf_scdet: add filter to detect scene change
Limin Wang
git at videolan.org
Thu May 14 18:36:54 EEST 2020
ffmpeg | branch: master | Limin Wang <lance.lmwang at gmail.com> | Tue Oct 8 23:28:36 2019 +0800| [d62d4e05e80342b0b42a6adfd957eda230655a54] | committer: Limin Wang
avfilter/vf_scdet: add filter to detect scene change
Reviewed-by: Paul B Mahol <onemda at gmail.com>
Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=d62d4e05e80342b0b42a6adfd957eda230655a54
---
Changelog | 1 +
configure | 1 +
doc/filters.texi | 35 ++++++++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/version.h | 2 +-
libavfilter/vf_scdet.c | 224 +++++++++++++++++++++++++++++++++++++++++++++++
7 files changed, 264 insertions(+), 1 deletion(-)
diff --git a/Changelog b/Changelog
index b75d2b6b96..f56674ffec 100644
--- a/Changelog
+++ b/Changelog
@@ -66,6 +66,7 @@ version <next>:
- asubboost filter
- Pro Pinball Series Soundbank demuxer
- pcm_rechunk bitstream filter
+- scdet filter
version 4.2:
diff --git a/configure b/configure
index a45c0fbde6..34afdaad28 100755
--- a/configure
+++ b/configure
@@ -3569,6 +3569,7 @@ sab_filter_deps="gpl swscale"
scale2ref_filter_deps="swscale"
scale_filter_deps="swscale"
scale_qsv_filter_deps="libmfx"
+scdet_filter_select="scene_sad"
select_filter_select="scene_sad"
sharpness_vaapi_filter_deps="vaapi"
showcqt_filter_deps="avcodec avformat swscale"
diff --git a/doc/filters.texi b/doc/filters.texi
index d19fd346ae..a3e78b1d20 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -16578,6 +16578,41 @@ Set the horizontal scrolling speed.
Set the vertical scrolling speed.
@end table
+ at anchor{scdet}
+ at section scdet
+
+Detect video scene change.
+
+This filter sets frame metadata with mafd between frame, the scene score, and
+forward the frame to the next filter, so they can use these metadata to detect
+scene change or others.
+
+In addition, this filter logs a message and sets frame metadata when it detects
+a scene change by @option{threshold}.
+
+ at code{lavfi.scd.mafd} metadata keys are set with mafd for every frame.
+
+ at code{lavfi.scd.score} metadata keys are set with scene change score for every frame
+to detect scene change.
+
+ at code{lavfi.scd.time} metadata keys are set with current filtered frame time which
+detect scene change with @option{threshold}.
+
+The filter accepts the following options:
+
+ at table @option
+ at item threshold, t
+Set the scene change detection threshold as a percentage of maximum change. Good
+values are in the @code{[8.0, 14.0]} range. The range for @option{threshold} is
+ at code{[0., 100.]}.
+
+Default value is @code{10.}.
+
+ at item sc_pass, s
+Set the flag to pass scene change frames to the next filter. Default value is @code{0}
+You can enable it if you want to get snapshot of scene change frames only.
+ at end table
+
@anchor{selectivecolor}
@section selectivecolor
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index f982afe15f..b2086f6fa9 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -376,6 +376,7 @@ OBJS-$(CONFIG_SCALE_QSV_FILTER) += vf_scale_qsv.o
OBJS-$(CONFIG_SCALE_VAAPI_FILTER) += vf_scale_vaapi.o scale_eval.o vaapi_vpp.o
OBJS-$(CONFIG_SCALE_VULKAN_FILTER) += vf_scale_vulkan.o vulkan.o
OBJS-$(CONFIG_SCALE2REF_FILTER) += vf_scale.o scale_eval.o
+OBJS-$(CONFIG_SCDET_FILTER) += vf_scdet.o
OBJS-$(CONFIG_SCROLL_FILTER) += vf_scroll.o
OBJS-$(CONFIG_SELECT_FILTER) += f_select.o
OBJS-$(CONFIG_SELECTIVECOLOR_FILTER) += vf_selectivecolor.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 1b94501da0..8830c8d871 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -358,6 +358,7 @@ extern AVFilter ff_vf_scale_qsv;
extern AVFilter ff_vf_scale_vaapi;
extern AVFilter ff_vf_scale_vulkan;
extern AVFilter ff_vf_scale2ref;
+extern AVFilter ff_vf_scdet;
extern AVFilter ff_vf_scroll;
extern AVFilter ff_vf_select;
extern AVFilter ff_vf_selectivecolor;
diff --git a/libavfilter/version.h b/libavfilter/version.h
index c0d496684e..8bb22c380f 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,7 +30,7 @@
#include "libavutil/version.h"
#define LIBAVFILTER_VERSION_MAJOR 7
-#define LIBAVFILTER_VERSION_MINOR 80
+#define LIBAVFILTER_VERSION_MINOR 81
#define LIBAVFILTER_VERSION_MICRO 100
diff --git a/libavfilter/vf_scdet.c b/libavfilter/vf_scdet.c
new file mode 100644
index 0000000000..b91d91f1e1
--- /dev/null
+++ b/libavfilter/vf_scdet.c
@@ -0,0 +1,224 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * video scene change detection filter
+ */
+
+#include "libavutil/avassert.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/timestamp.h"
+
+#include "avfilter.h"
+#include "filters.h"
+#include "scene_sad.h"
+
+typedef struct SCDetContext {
+ const AVClass *class;
+
+ ptrdiff_t width[4];
+ ptrdiff_t height[4];
+ int nb_planes;
+ int bitdepth;
+ ff_scene_sad_fn sad;
+ double prev_mafd;
+ double scene_score;
+ AVFrame *prev_picref;
+ double threshold;
+ int sc_pass;
+} SCDetContext;
+
+#define OFFSET(x) offsetof(SCDetContext, x)
+#define V AV_OPT_FLAG_VIDEO_PARAM
+#define F AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption scdet_options[] = {
+ { "threshold", "set scene change detect threshold", OFFSET(threshold), AV_OPT_TYPE_DOUBLE, {.dbl = 10.}, 0, 100., V|F },
+ { "t", "set scene change detect threshold", OFFSET(threshold), AV_OPT_TYPE_DOUBLE, {.dbl = 10.}, 0, 100., V|F },
+ { "sc_pass", "Set the flag to pass scene change frames", OFFSET(sc_pass), AV_OPT_TYPE_BOOL, {.dbl = 0 }, 0, 1, V|F },
+ { "s", "Set the flag to pass scene change frames", OFFSET(sc_pass), AV_OPT_TYPE_BOOL, {.dbl = 0 }, 0, 1, V|F },
+ {NULL}
+};
+
+AVFILTER_DEFINE_CLASS(scdet);
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static const enum AVPixelFormat pix_fmts[] = {
+ AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24, AV_PIX_FMT_RGBA,
+ AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA, AV_PIX_FMT_GRAY8,
+ AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P,
+ AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVJ422P,
+ AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUVJ440P,
+ AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P,
+ AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV420P12,
+ AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV422P12,
+ AV_PIX_FMT_YUV444P9, AV_PIX_FMT_YUV444P10, AV_PIX_FMT_YUV444P12,
+ AV_PIX_FMT_NONE
+ };
+
+ AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
+ if (!fmts_list)
+ return AVERROR(ENOMEM);
+ return ff_set_common_formats(ctx, fmts_list);
+}
+
+static int config_input(AVFilterLink *inlink)
+{
+ AVFilterContext *ctx = inlink->dst;
+ SCDetContext *s = ctx->priv;
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
+ int is_yuv = !(desc->flags & AV_PIX_FMT_FLAG_RGB) &&
+ (desc->flags & AV_PIX_FMT_FLAG_PLANAR) &&
+ desc->nb_components >= 3;
+
+ s->bitdepth = desc->comp[0].depth;
+ s->nb_planes = is_yuv ? 1 : av_pix_fmt_count_planes(inlink->format);
+
+ for (int plane = 0; plane < 4; plane++) {
+ ptrdiff_t line_size = av_image_get_linesize(inlink->format, inlink->w, plane);
+ s->width[plane] = line_size >> (s->bitdepth > 8);
+ s->height[plane] = inlink->h >> ((plane == 1 || plane == 2) ? desc->log2_chroma_h : 0);
+ }
+
+ s->sad = ff_scene_sad_get_fn(s->bitdepth == 8 ? 8 : 16);
+ if (!s->sad)
+ return AVERROR(EINVAL);
+
+ return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ SCDetContext *s = ctx->priv;
+
+ av_frame_free(&s->prev_picref);
+}
+
+static double get_scene_score(AVFilterContext *ctx, AVFrame *frame)
+{
+ double ret = 0;
+ SCDetContext *s = ctx->priv;
+ AVFrame *prev_picref = s->prev_picref;
+
+ if (prev_picref && frame->height == prev_picref->height
+ && frame->width == prev_picref->width) {
+ uint64_t sad = 0;
+ double mafd, diff;
+ uint64_t count = 0;
+
+ for (int plane = 0; plane < s->nb_planes; plane++) {
+ uint64_t plane_sad;
+ s->sad(prev_picref->data[plane], prev_picref->linesize[plane],
+ frame->data[plane], frame->linesize[plane],
+ s->width[plane], s->height[plane], &plane_sad);
+ sad += plane_sad;
+ count += s->width[plane] * s->height[plane];
+ }
+
+ emms_c();
+ mafd = (double)sad * 100. / count / (1ULL << s->bitdepth);
+ diff = fabs(mafd - s->prev_mafd);
+ ret = av_clipf(FFMIN(mafd, diff), 0, 100.);
+ s->prev_mafd = mafd;
+ av_frame_free(&prev_picref);
+ }
+ s->prev_picref = av_frame_clone(frame);
+ return ret;
+}
+
+static int set_meta(SCDetContext *s, AVFrame *frame, const char *key, const char *value)
+{
+ return av_dict_set(&frame->metadata, key, value, 0);
+}
+
+static int activate(AVFilterContext *ctx)
+{
+ int ret;
+ AVFilterLink *inlink = ctx->inputs[0];
+ AVFilterLink *outlink = ctx->outputs[0];
+ SCDetContext *s = ctx->priv;
+ AVFrame *frame;
+
+ FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink);
+
+ ret = ff_inlink_consume_frame(inlink, &frame);
+ if (ret < 0)
+ return ret;
+
+ if (frame) {
+ char buf[64];
+ s->scene_score = get_scene_score(ctx, frame);
+ snprintf(buf, sizeof(buf), "%0.3f", s->prev_mafd);
+ set_meta(s, frame, "lavfi.scd.mafd", buf);
+ snprintf(buf, sizeof(buf), "%0.3f", s->scene_score);
+ set_meta(s, frame, "lavfi.scd.score", buf);
+
+ if (s->scene_score > s->threshold) {
+ av_log(s, AV_LOG_INFO, "lavfi.scd.score: %.3f, lavfi.scd.time: %s\n",
+ s->scene_score, av_ts2timestr(frame->pts, &inlink->time_base));
+ set_meta(s, frame, "lavfi.scd.time",
+ av_ts2timestr(frame->pts, &inlink->time_base));
+ }
+ if (s->sc_pass) {
+ if (s->scene_score > s->threshold)
+ return ff_filter_frame(outlink, frame);
+ else {
+ av_frame_free(&frame);
+ }
+ } else
+ return ff_filter_frame(outlink, frame);
+ }
+
+ FF_FILTER_FORWARD_STATUS(inlink, outlink);
+ FF_FILTER_FORWARD_WANTED(outlink, inlink);
+
+ return FFERROR_NOT_READY;
+}
+
+static const AVFilterPad scdet_inputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_input,
+ },
+ { NULL }
+};
+
+static const AVFilterPad scdet_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ },
+ { NULL }
+};
+
+AVFilter ff_vf_scdet = {
+ .name = "scdet",
+ .description = NULL_IF_CONFIG_SMALL("Detect video scene change"),
+ .priv_size = sizeof(SCDetContext),
+ .priv_class = &scdet_class,
+ .uninit = uninit,
+ .query_formats = query_formats,
+ .inputs = scdet_inputs,
+ .outputs = scdet_outputs,
+ .activate = activate,
+};
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