[FFmpeg-cvslog] avfilter: add find_rect filter
Michael Niedermayer
git at videolan.org
Sat May 2 21:24:11 CEST 2015
ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Sat May 2 21:00:01 2015 +0200| [94340e4b28cc73ca7f9895892a2768df68d027a0] | committer: Michael Niedermayer
avfilter: add find_rect filter
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=94340e4b28cc73ca7f9895892a2768df68d027a0
---
configure | 1 +
doc/filters.texi | 30 +++++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/version.h | 2 +-
libavfilter/vf_find_rect.c | 311 ++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 345 insertions(+), 1 deletion(-)
diff --git a/configure b/configure
index 88e0d97..f1248e6 100755
--- a/configure
+++ b/configure
@@ -2644,6 +2644,7 @@ eq_filter_deps="gpl"
fftfilt_filter_deps="avcodec"
fftfilt_filter_select="rdft"
flite_filter_deps="libflite"
+find_rect_filter_deps="gpl"
frei0r_filter_deps="frei0r dlopen"
frei0r_src_filter_deps="frei0r dlopen"
fspp_filter_deps="gpl"
diff --git a/doc/filters.texi b/doc/filters.texi
index b7a9c9b..68ad413 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -5163,6 +5163,36 @@ framework.
It does not take parameters.
+ at section find_rect
+
+Find a rectangular object
+
+It accepts the following options:
+
+ at table @option
+ at item object
+Filepath of the object image, needs to be in gray8.
+
+ at item threshold
+Detection threshold, default is 0.5.
+
+ at item mipmaps
+Number of mipmaps, default is 3.
+
+ at item xmin, ymin, xmax, ymax
+Specifies the rectangle in which to search.
+ at end table
+
+ at subsection Examples
+
+ at itemize
+ at item
+Generate a representative palette of a given video using @command{ffmpeg}:
+ at example
+ffmpeg -i file.ts -vf find_rect=newref.pgm,cover_rect=cover.jpg:mode=cover new.mkv
+ at end example
+ at end itemize
+
@anchor{format}
@section format
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 48cee50..57619d6 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -126,6 +126,7 @@ OBJS-$(CONFIG_FFTFILT_FILTER) += vf_fftfilt.o
OBJS-$(CONFIG_FIELD_FILTER) += vf_field.o
OBJS-$(CONFIG_FIELDMATCH_FILTER) += vf_fieldmatch.o
OBJS-$(CONFIG_FIELDORDER_FILTER) += vf_fieldorder.o
+OBJS-$(CONFIG_FIND_RECT_FILTER) += vf_find_rect.o
OBJS-$(CONFIG_FORMAT_FILTER) += vf_format.o
OBJS-$(CONFIG_FRAMESTEP_FILTER) += vf_framestep.o
OBJS-$(CONFIG_FPS_FILTER) += vf_fps.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 7961dca..bb19200 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -142,6 +142,7 @@ void avfilter_register_all(void)
REGISTER_FILTER(FIELD, field, vf);
REGISTER_FILTER(FIELDMATCH, fieldmatch, vf);
REGISTER_FILTER(FIELDORDER, fieldorder, vf);
+ REGISTER_FILTER(FIND_RECT, find_rect, vf);
REGISTER_FILTER(FORMAT, format, vf);
REGISTER_FILTER(FPS, fps, vf);
REGISTER_FILTER(FRAMEPACK, framepack, vf);
diff --git a/libavfilter/version.h b/libavfilter/version.h
index a4a9e63..d6dc95a 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,7 +30,7 @@
#include "libavutil/version.h"
#define LIBAVFILTER_VERSION_MAJOR 5
-#define LIBAVFILTER_VERSION_MINOR 14
+#define LIBAVFILTER_VERSION_MINOR 15
#define LIBAVFILTER_VERSION_MICRO 100
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
diff --git a/libavfilter/vf_find_rect.c b/libavfilter/vf_find_rect.c
new file mode 100644
index 0000000..a4631de
--- /dev/null
+++ b/libavfilter/vf_find_rect.c
@@ -0,0 +1,311 @@
+/*
+ * Copyright (c) 2014-2015 Michael Niedermayer <michaelni at gmx.at>
+ *
+ * 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.
+ */
+
+/**
+ * @todo switch to dualinput
+ */
+
+#include "libavutil/avassert.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/opt.h"
+#include "internal.h"
+
+#include "lavfutils.h"
+
+#define MAX_MIPMAPS 5
+
+typedef struct FOCContext {
+ AVClass *class;
+ float threshold;
+ int mipmaps;
+ int xmin, ymin, xmax, ymax;
+ char *obj_filename;
+ int last_x, last_y;
+ AVFrame *obj_frame;
+ AVFrame *needle_frame[MAX_MIPMAPS];
+ AVFrame *haystack_frame[MAX_MIPMAPS];
+} FOCContext;
+
+#define OFFSET(x) offsetof(FOCContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+static const AVOption foc_options[] = {
+ { "object", "object bitmap filename", OFFSET(obj_filename), AV_OPT_TYPE_STRING, {.str = NULL}, .flags = FLAGS },
+ { "threshold", "set threshold", OFFSET(threshold), AV_OPT_TYPE_FLOAT, {.dbl = 0.5}, 0, 1.0, FLAGS },
+ { "mipmaps", "set mipmaps", OFFSET(mipmaps), AV_OPT_TYPE_INT, {.i64 = 3}, 1, MAX_MIPMAPS, FLAGS },
+ { "xmin", "", OFFSET(xmin), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
+ { "ymin", "", OFFSET(ymin), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
+ { "xmax", "", OFFSET(xmax), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
+ { "ymax", "", OFFSET(ymax), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
+ { NULL }
+};
+
+static const AVClass foc_class = {
+ .class_name = "find_rect",
+ .item_name = av_default_item_name,
+ .option = foc_options,
+ .version = LIBAVUTIL_VERSION_INT,
+ .category = AV_CLASS_CATEGORY_FILTER,
+};
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static const enum AVPixelFormat pix_fmts[] = {
+ AV_PIX_FMT_YUV420P,
+ AV_PIX_FMT_YUVJ420P,
+ AV_PIX_FMT_NONE
+ };
+
+ return ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
+}
+
+static AVFrame *downscale(AVFrame *in)
+{
+ int x, y;
+ AVFrame *frame = av_frame_alloc();
+ uint8_t *src, *dst;
+ if (!frame)
+ return NULL;
+
+ frame->format = in->format;
+ frame->width = (in->width + 1) / 2;
+ frame->height = (in->height+ 1) / 2;
+
+ if (av_frame_get_buffer(frame, 32) < 0) {
+ av_frame_free(&frame);
+ return NULL;
+ }
+ src = in ->data[0];
+ dst = frame->data[0];
+
+ for(y = 0; y < frame->height; y++) {
+ for(x = 0; x < frame->width; x++) {
+ dst[x] = ( src[2*x+0]
+ + src[2*x+1]
+ + src[2*x+0 + in->linesize[0]]
+ + src[2*x+1 + in->linesize[0]]
+ + 2) >> 2;
+ }
+ src += 2*in->linesize[0];
+ dst += frame->linesize[0];
+ }
+ return frame;
+}
+
+static float compare(const AVFrame *haystack, const AVFrame *obj, int offx, int offy)
+{
+ int x,y;
+ int o_sum_v = 0;
+ int h_sum_v = 0;
+ int64_t oo_sum_v = 0;
+ int64_t hh_sum_v = 0;
+ int64_t oh_sum_v = 0;
+ float c;
+ int n = obj->height * obj->width;
+ const uint8_t *odat = obj ->data[0];
+ const uint8_t *hdat = haystack->data[0] + offx + offy * haystack->linesize[0];
+ int64_t o_sigma, h_sigma;
+
+ for(y = 0; y < obj->height; y++) {
+ for(x = 0; x < obj->width; x++) {
+ int o_v = odat[x];
+ int h_v = hdat[x];
+ o_sum_v += o_v;
+ h_sum_v += h_v;
+ oo_sum_v += o_v * o_v;
+ hh_sum_v += h_v * h_v;
+ oh_sum_v += o_v * h_v;
+ }
+ odat += obj->linesize[0];
+ hdat += haystack->linesize[0];
+ }
+ o_sigma = n*oo_sum_v - o_sum_v*(int64_t)o_sum_v;
+ h_sigma = n*hh_sum_v - h_sum_v*(int64_t)h_sum_v;
+
+ if (o_sigma == 0 || h_sigma == 0)
+ return 1.0;
+
+ c = (n*oh_sum_v - o_sum_v*(int64_t)h_sum_v) / (sqrt(o_sigma)*sqrt(h_sigma));
+
+ return 1 - fabs(c);
+}
+
+static int config_input(AVFilterLink *inlink)
+{
+ AVFilterContext *ctx = inlink->dst;
+ FOCContext *foc = ctx->priv;
+
+ if (foc->xmax <= 0)
+ foc->xmax = inlink->w - foc->obj_frame->width;
+ if (foc->ymax <= 0)
+ foc->ymax = inlink->h - foc->obj_frame->height;
+
+ return 0;
+}
+
+static float search(FOCContext *foc, int pass, int maxpass, int xmin, int xmax, int ymin, int ymax, int *best_x, int *best_y, float best_score)
+{
+ int x, y;
+
+ if (pass + 1 <= maxpass) {
+ int sub_x, sub_y;
+ search(foc, pass+1, maxpass, xmin>>1, (xmax+1)>>1, ymin>>1, (ymax+1)>>1, &sub_x, &sub_y, 1.0);
+ xmin = FFMAX(xmin, 2*sub_x - 4);
+ xmax = FFMIN(xmax, 2*sub_x + 4);
+ ymin = FFMAX(ymin, 2*sub_y - 4);
+ ymax = FFMIN(ymax, 2*sub_y + 4);
+ }
+
+ for (y = ymin; y <= ymax; y++) {
+ for (x = xmin; x <= xmax; x++) {
+ float score = compare(foc->haystack_frame[pass], foc->needle_frame[pass], x, y);
+ av_assert0(score != 0);
+ if (score < best_score) {
+ best_score = score;
+ *best_x = x;
+ *best_y = y;
+ }
+ }
+ }
+ return best_score;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+{
+ AVFilterContext *ctx = inlink->dst;
+ FOCContext *foc = ctx->priv;
+ float best_score;
+ int best_x, best_y;
+ int i;
+
+ foc->haystack_frame[0] = av_frame_clone(in);
+ for (i=1; i<foc->mipmaps; i++) {
+ foc->haystack_frame[i] = downscale(foc->haystack_frame[i-1]);
+ }
+
+ best_score = search(foc, 0, 0,
+ FFMAX(foc->xmin, foc->last_x - 8),
+ FFMIN(foc->xmax, foc->last_x + 8),
+ FFMAX(foc->ymin, foc->last_y - 8),
+ FFMIN(foc->ymax, foc->last_y + 8),
+ &best_x, &best_y, 1.0);
+
+ best_score = search(foc, 0, foc->mipmaps - 1, foc->xmin, foc->xmax, foc->ymin, foc->ymax,
+ &best_x, &best_y, best_score);
+
+ for (i=0; i<MAX_MIPMAPS; i++) {
+ av_frame_free(&foc->haystack_frame[i]);
+ }
+
+ if (best_score > foc->threshold) {
+ return ff_filter_frame(ctx->outputs[0], in);
+ }
+
+ av_log(ctx, AV_LOG_DEBUG, "Found at %d %d score %f\n", best_x, best_y, best_score);
+ foc->last_x = best_x;
+ foc->last_y = best_y;
+
+ av_frame_make_writable(in);
+
+ av_dict_set_int(&in->metadata, "lavfi.rect.w", foc->obj_frame->width, 0);
+ av_dict_set_int(&in->metadata, "lavfi.rect.h", foc->obj_frame->height, 0);
+ av_dict_set_int(&in->metadata, "lavfi.rect.x", best_x, 0);
+ av_dict_set_int(&in->metadata, "lavfi.rect.y", best_y, 0);
+
+ return ff_filter_frame(ctx->outputs[0], in);
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ FOCContext *foc = ctx->priv;
+ int i;
+
+ for (i = 0; i < MAX_MIPMAPS; i++) {
+ av_frame_free(&foc->needle_frame[i]);
+ av_frame_free(&foc->haystack_frame[i]);
+ }
+
+ if (foc->obj_frame)
+ av_freep(&foc->obj_frame->data[0]);
+ av_frame_free(&foc->obj_frame);
+}
+
+static av_cold int init(AVFilterContext *ctx)
+{
+ FOCContext *foc = ctx->priv;
+ int ret, i;
+
+ if (!foc->obj_filename) {
+ av_log(ctx, AV_LOG_ERROR, "object filename not set\n");
+ return AVERROR(EINVAL);
+ }
+
+ foc->obj_frame = av_frame_alloc();
+ if (!foc->obj_frame)
+ return AVERROR(ENOMEM);
+
+ if ((ret = ff_load_image(foc->obj_frame->data, foc->obj_frame->linesize,
+ &foc->obj_frame->width, &foc->obj_frame->height,
+ &foc->obj_frame->format, foc->obj_filename, ctx)) < 0)
+ return ret;
+
+ if (foc->obj_frame->format != AV_PIX_FMT_GRAY8) {
+ av_log(ctx, AV_LOG_ERROR, "object image is not a grayscale image\n");
+ return AVERROR(EINVAL);
+ }
+
+ foc->needle_frame[0] = av_frame_clone(foc->obj_frame);
+ for (i = 1; i < foc->mipmaps; i++) {
+ foc->needle_frame[i] = downscale(foc->needle_frame[i-1]);
+ if (!foc->needle_frame[i])
+ return AVERROR(ENOMEM);
+ }
+
+ return 0;
+}
+
+static const AVFilterPad foc_inputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_input,
+ .filter_frame = filter_frame,
+ },
+ { NULL }
+};
+
+static const AVFilterPad foc_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ },
+ { NULL }
+};
+
+AVFilter ff_vf_find_rect = {
+ .name = "find_rect",
+ .description = NULL_IF_CONFIG_SMALL("Find a user specified object"),
+ .priv_size = sizeof(FOCContext),
+ .init = init,
+ .uninit = uninit,
+ .query_formats = query_formats,
+ .inputs = foc_inputs,
+ .outputs = foc_outputs,
+ .priv_class = &foc_class,
+};
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