@@ -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"

@@ -5163,6 +5163,36 @@ framework.

 It does not take parameters.

+@section find_rect

+

+Find a rectangular object

+

+It accepts the following options:

+

+@table @option

+@item object

+Filepath of the object image, needs to be in gray8.

+

+@item threshold

+Detection threshold, default is 0.5.

+

+@item mipmaps

+Number of mipmaps, default is 3.

+

+@item xmin, ymin, xmax, ymax

+Specifies the rectangle in which to search.

+@end table

+

+@subsection Examples

+

+@itemize

+@item

+Generate a representative palette of a given video using @command{ffmpeg}:

+@example

+ffmpeg -i file.ts -vf find_rect=newref.pgm,cover_rect=cover.jpg:mode=cover new.mkv

+@end example

+@end itemize

+

 @anchor{format}

 @section format

@@ -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

@@ -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);

@@ -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, \

new file mode 100644

@@ -0,0 +1,311 @@

+/*

+ * Copyright (c) 2014-2015 Michael Niedermayer <michaelni@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,

+};