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-rw-r--r--Changelog1
-rwxr-xr-xconfigure1
-rw-r--r--doc/filters.texi21
-rw-r--r--libavfilter/Makefile1
-rw-r--r--libavfilter/allfilters.c1
-rw-r--r--libavfilter/avfilter.h2
-rw-r--r--libavfilter/vf_blackframe.c129
7 files changed, 155 insertions, 1 deletions
diff --git a/Changelog b/Changelog
index 98ed541a62..a76cec195c 100644
--- a/Changelog
+++ b/Changelog
@@ -41,6 +41,7 @@ version <next>:
- make the crop filter accept parametric expressions
- make ffprobe accept AVFormatContext options
- yadif filter
+- blackframe filter
version 0.6:
diff --git a/configure b/configure
index d08deb0d0b..32634c051c 100755
--- a/configure
+++ b/configure
@@ -1401,6 +1401,7 @@ tcp_protocol_deps="network"
udp_protocol_deps="network"
# filters
+blackframe_filter_deps="gpl"
ocv_smooth_filter_deps="libopencv"
yadif_filter_deps="gpl"
diff --git a/doc/filters.texi b/doc/filters.texi
index d000276599..5ebaf99f4c 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -71,6 +71,27 @@ build.
Below is a description of the currently available video filters.
+@section blackframe
+
+Detect frames that are (almost) completely black. Can be useful to
+detect chapter transitions or commercials. Output lines consist of
+the frame number of the detected frame, the percentage of blackness,
+the position in the file if known or -1 and the timestamp in seconds.
+
+In order to display the output lines, you need to set the loglevel at
+least to the AV_LOG_INFO value.
+
+The filter accepts the syntax:
+@example
+blackframe[=@var{amount}:[@var{threshold}]]
+@end example
+
+@var{amount} is the percentage of the pixels that have to be below the
+threshold, and defaults to 98.
+
+@var{threshold} is the threshold below which a pixel value is
+considered black, and defaults to 32.
+
@section crop
Crop the input video to @var{out_w}:@var{out_h}:@var{x}:@var{y}.
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 174b83ea02..51fe208a4e 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -21,6 +21,7 @@ OBJS-$(CONFIG_ANULLSRC_FILTER) += asrc_anullsrc.o
OBJS-$(CONFIG_ANULLSINK_FILTER) += asink_anullsink.o
OBJS-$(CONFIG_ASPECT_FILTER) += vf_aspect.o
+OBJS-$(CONFIG_BLACKFRAME_FILTER) += vf_blackframe.o
OBJS-$(CONFIG_CROP_FILTER) += vf_crop.o
OBJS-$(CONFIG_FIFO_FILTER) += vf_fifo.o
OBJS-$(CONFIG_FORMAT_FILTER) += vf_format.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index ec7d933115..d9681e67d8 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -41,6 +41,7 @@ void avfilter_register_all(void)
REGISTER_FILTER (ANULLSINK, anullsink, asink);
REGISTER_FILTER (ASPECT, aspect, vf);
+ REGISTER_FILTER (BLACKFRAME, blackframe, vf);
REGISTER_FILTER (CROP, crop, vf);
REGISTER_FILTER (FIFO, fifo, vf);
REGISTER_FILTER (FORMAT, format, vf);
diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index c2a997998f..05ef354521 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -25,7 +25,7 @@
#include "libavutil/avutil.h"
#define LIBAVFILTER_VERSION_MAJOR 1
-#define LIBAVFILTER_VERSION_MINOR 45
+#define LIBAVFILTER_VERSION_MINOR 46
#define LIBAVFILTER_VERSION_MICRO 0
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
diff --git a/libavfilter/vf_blackframe.c b/libavfilter/vf_blackframe.c
new file mode 100644
index 0000000000..0645ffa219
--- /dev/null
+++ b/libavfilter/vf_blackframe.c
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2010 Stefano Sabatini
+ * Copyright (C) 2006 Ivo van Poorten
+ * Copyright (C) 2006 Julian Hall
+ * Copyright (C) 2002-2003 Brian J. Murrell
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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
+ * Search for black frames to detect scene transitions.
+ * Ported from MPlayer libmpcodecs/vf_blackframe.c.
+ */
+
+#include "avfilter.h"
+
+typedef struct {
+ unsigned int bamount; ///< black amount
+ unsigned int bthresh; ///< black threshold
+ unsigned int frame; ///< frame number
+ unsigned int nblack; ///< number of black pixels counted so far
+} BlackFrameContext;
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static const enum PixelFormat pix_fmts[] = {
+ PIX_FMT_YUV410P, PIX_FMT_YUV420P, PIX_FMT_GRAY8, PIX_FMT_NV12,
+ PIX_FMT_NV21, PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV411P,
+ PIX_FMT_NONE
+ };
+
+ avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
+ return 0;
+}
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+ BlackFrameContext *blackframe = ctx->priv;
+
+ blackframe->bamount = 98;
+ blackframe->bthresh = 32;
+ blackframe->nblack = 0;
+ blackframe->frame = 0;
+
+ if (args)
+ sscanf(args, "%u:%u", &blackframe->bamount, &blackframe->bthresh);
+
+ av_log(ctx, AV_LOG_INFO, "bamount:%u bthresh:%u\n",
+ blackframe->bamount, blackframe->bthresh);
+
+ if (blackframe->bamount > 100 || blackframe->bthresh > 255) {
+ av_log(ctx, AV_LOG_ERROR, "Too big value for bamount (max is 100) or bthresh (max is 255)\n");
+ return AVERROR(EINVAL);
+ }
+
+ return 0;
+}
+
+static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
+{
+ AVFilterContext *ctx = inlink->dst;
+ BlackFrameContext *blackframe = ctx->priv;
+ AVFilterBufferRef *picref = inlink->cur_buf;
+ int x, i;
+ uint8_t *p = picref->data[0] + y * picref->linesize[0];
+
+ for (i = 0; i < h; i++) {
+ for (x = 0; x < inlink->w; x++)
+ blackframe->nblack += p[x] < blackframe->bthresh;
+ p += picref->linesize[0];
+ }
+
+ avfilter_draw_slice(ctx->outputs[0], y, h, slice_dir);
+}
+
+static void end_frame(AVFilterLink *inlink)
+{
+ AVFilterContext *ctx = inlink->dst;
+ BlackFrameContext *blackframe = ctx->priv;
+ AVFilterBufferRef *picref = inlink->cur_buf;
+ int pblack = 0;
+
+ pblack = blackframe->nblack * 100 / (inlink->w * inlink->h);
+ if (pblack >= blackframe->bamount)
+ av_log(ctx, AV_LOG_INFO, "frame:%u pblack:%u pos:%"PRId64" pts:%f\n",
+ blackframe->frame, pblack, picref->pos,
+ picref->pts == AV_NOPTS_VALUE ? -1 : (double)picref->pts / AV_TIME_BASE);
+
+ blackframe->frame++;
+ blackframe->nblack = 0;
+ avfilter_end_frame(inlink->dst->outputs[0]);
+}
+
+AVFilter avfilter_vf_blackframe = {
+ .name = "blackframe",
+ .description = NULL_IF_CONFIG_SMALL("Detect frames that are (almost) black."),
+
+ .priv_size = sizeof(BlackFrameContext),
+ .init = init,
+
+ .query_formats = query_formats,
+
+ .inputs = (AVFilterPad[]) {{ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .draw_slice = draw_slice,
+ .get_video_buffer = avfilter_null_get_video_buffer,
+ .start_frame = avfilter_null_start_frame,
+ .end_frame = end_frame, },
+ { .name = NULL}},
+
+ .outputs = (AVFilterPad[]) {{ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO },
+ { .name = NULL}},
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-28 06:13:16 +0000