@@ -4,6 +4,7 @@ releases are sorted from youngest to oldest.

 version next:

 - openal input device added

+- boxblur filter added

 version 0.8:

@@ -1497,6 +1497,7 @@ udp_protocol_deps="network"

 # filters

 blackframe_filter_deps="gpl"

+boxblur_filter_deps="gpl"

 cropdetect_filter_deps="gpl"

 drawtext_filter_deps="libfreetype"

 frei0r_filter_deps="frei0r dlopen strtok_r"

@@ -183,6 +183,66 @@ threshold, and defaults to 98.

 @var{threshold} is the threshold below which a pixel value is

 considered black, and defaults to 32.

+@section boxblur

+

+Apply boxblur algorithm to the input video.

+

+This filter accepts the parameters:

+@var{luma_power}:@var{luma_radius}:@var{chroma_radius}:@var{chroma_power}:@var{alpha_radius}:@var{alpha_power}

+

+Chroma and alpha parameters are optional, if not specified they default

+to the corresponding values set for @var{luma_radius} and

+@var{luma_power}.

+

+@var{luma_radius}, @var{chroma_radius}, and @var{alpha_radius} represent

+the radius in pixels of the box used for blurring the corresponding

+input plane. They are expressions, and can contain the following

+constants:

+@table @option

+@item w, h

+the input width and heigth in pixels

+

+@item cw, ch

+the input chroma image width and height in pixels

+

+@item hsub, vsub

+horizontal and vertical chroma subsample values. For example for the

+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.

+@end table

+

+The radius must be a non-negative number, and must be not greater than

+the value of the expression @code{min(w,h)/2} for the luma and alpha planes,

+and of @code{min(cw,ch)/2} for the chroma planes.

+

+@var{luma_power}, @var{chroma_power}, and @var{alpha_power} represent

+how many times the boxblur filter is applied to the corresponding

+plane.

+

+Some examples follow:

+

+@itemize

+

+@item

+Apply a boxblur filter with luma, chroma, and alpha radius

+set to 2:

+@example

+boxblur=2:1

+@end example

+

+@item

+Set luma radius to 2, alpha and chroma radius to 0

+@example

+boxblur=2:1:0:0:0:0

+@end example

+

+@item

+Set luma and chroma radius to a fraction of the video dimension

+@example

+boxblur=min(h\,w)/10:1:min(cw\,ch)/10:1

+@end example

+

+@end itemize

+

 @section copy

 Copy the input source unchanged to the output. Mainly useful for

@@ -25,6 +25,7 @@ OBJS-$(CONFIG_ANULLSRC_FILTER)               += asrc_anullsrc.o

 OBJS-$(CONFIG_ANULLSINK_FILTER)              += asink_anullsink.o

 OBJS-$(CONFIG_BLACKFRAME_FILTER)             += vf_blackframe.o

+OBJS-$(CONFIG_BOXBLUR_FILTER)                += vf_boxblur.o

 OBJS-$(CONFIG_COPY_FILTER)                   += vf_copy.o

 OBJS-$(CONFIG_CROP_FILTER)                   += vf_crop.o

 OBJS-$(CONFIG_CROPDETECT_FILTER)             += vf_cropdetect.o

@@ -41,6 +41,7 @@ void avfilter_register_all(void)

     REGISTER_FILTER (ANULLSINK,   anullsink,   asink);

     REGISTER_FILTER (BLACKFRAME,  blackframe,  vf);

+    REGISTER_FILTER (BOXBLUR,     boxblur,     vf);

     REGISTER_FILTER (COPY,        copy,        vf);

     REGISTER_FILTER (CROP,        crop,        vf);

     REGISTER_FILTER (CROPDETECT,  cropdetect,  vf);

@@ -29,8 +29,8 @@

 #include "libavutil/rational.h"

 #define LIBAVFILTER_VERSION_MAJOR  2

-#define LIBAVFILTER_VERSION_MINOR 24

-#define LIBAVFILTER_VERSION_MICRO  4

+#define LIBAVFILTER_VERSION_MINOR 25

+#define LIBAVFILTER_VERSION_MICRO  0

 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \

                                                LIBAVFILTER_VERSION_MINOR, \

new file mode 100644

@@ -0,0 +1,350 @@

+/*

+ * Copyright (c) 2002 Michael Niedermayer <michaelni@gmx.at>

+ * Copyright (c) 2011 Stefano Sabatini

+ *

+ * 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

+ * Apply a boxblur filter to the input video.

+ * Ported from MPlayer libmpcodecs/vf_boxblur.c.

+ */

+

+#include "libavutil/avstring.h"

+#include "libavutil/eval.h"

+#include "libavutil/pixdesc.h"

+#include "avfilter.h"

+

+static const char *var_names[] = {

+    "w",

+    "h",

+    "cw",

+    "ch",

+    "hsub",

+    "vsub",

+    NULL

+};

+

+enum var_name {

+    VAR_W,

+    VAR_H,

+    VAR_CW,

+    VAR_CH,

+    VAR_HSUB,

+    VAR_VSUB,

+    VARS_NB

+};

+

+typedef struct {

+    int radius;

+    int power;

+} FilterParam;

+

+typedef struct {

+    FilterParam luma_param;

+    FilterParam chroma_param;

+    FilterParam alpha_param;

+    char luma_radius_expr  [256];

+    char chroma_radius_expr[256];

+    char alpha_radius_expr [256];

+

+    int hsub, vsub;

+    int radius[4];

+    int power[4];

+    uint8_t *temp[2]; ///< temporary buffer used in blur_power()

+} BoxBlurContext;

+

+#define Y 0

+#define U 1

+#define V 2

+#define A 3

+

+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)

+{

+    BoxBlurContext *boxblur = ctx->priv;

+    int e;

+

+    if (!args) {

+        av_log(ctx, AV_LOG_ERROR,

+               "Filter expects 2 or 4 arguments, none provided\n");

+        return AVERROR(EINVAL);

+    }

+

+    e = sscanf(args, "%255[^:]:%d:%255[^:]:%d:%255[^:]:%d",

+               boxblur->luma_radius_expr,   &boxblur->luma_param  .power,

+               boxblur->chroma_radius_expr, &boxblur->chroma_param.power,

+               boxblur->alpha_radius_expr,  &boxblur->alpha_param .power);

+

+    if (e != 2 && e != 4 && e != 6) {

+        av_log(ctx, AV_LOG_ERROR,

+               "Filter expects 2 or 4 or 6 params, provided %d\n", e);

+        return AVERROR(EINVAL);

+    }

+

+    if (e < 4) {

+        boxblur->chroma_param.power = boxblur->luma_param.power;

+        av_strlcpy(boxblur->chroma_radius_expr, boxblur->luma_radius_expr,

+                   sizeof(boxblur->chroma_radius_expr));

+    }

+    if (e < 6) {

+        boxblur->alpha_param.power = boxblur->luma_param.power;

+        av_strlcpy(boxblur->alpha_radius_expr, boxblur->luma_radius_expr,

+                   sizeof(boxblur->alpha_radius_expr));

+    }

+

+    return 0;

+}

+

+static av_cold void uninit(AVFilterContext *ctx)

+{

+    BoxBlurContext *boxblur = ctx->priv;

+

+    av_freep(&boxblur->temp[0]);

+    av_freep(&boxblur->temp[1]);

+}

+

+static int query_formats(AVFilterContext *ctx)

+{

+    enum PixelFormat pix_fmts[] = {

+        PIX_FMT_YUV444P,  PIX_FMT_YUV422P,  PIX_FMT_YUV420P,

+        PIX_FMT_YUV411P,  PIX_FMT_YUV410P,  PIX_FMT_YUVA420P,

+        PIX_FMT_YUV440P,  PIX_FMT_GRAY8,

+        PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P,

+        PIX_FMT_YUVJ440P,

+        PIX_FMT_NONE

+    };

+

+    avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));

+    return 0;

+}

+

+static int config_input(AVFilterLink *inlink)

+{

+    AVFilterContext *ctx = inlink->dst;

+    BoxBlurContext *boxblur = ctx->priv;

+    const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[inlink->format];

+    int w = inlink->w, h = inlink->h;

+    int cw, ch;

+    double var_values[VARS_NB], res;

+    char *expr;

+    int ret;

+

+    if (!(boxblur->temp[0] = av_malloc(w)) ||

+        !(boxblur->temp[1] = av_malloc(w)))

+        return AVERROR(ENOMEM);

+

+    boxblur->hsub = desc->log2_chroma_w;

+    boxblur->vsub = desc->log2_chroma_h;

+

+    var_values[VAR_W]  = inlink->w;

+    var_values[VAR_H]  = inlink->h;

+    var_values[VAR_CW] = cw = w>>boxblur->hsub;

+    var_values[VAR_CH] = ch = h>>boxblur->vsub;

+    var_values[VAR_HSUB] = 1<<boxblur->hsub;

+    var_values[VAR_VSUB] = 1<<boxblur->vsub;

+

+#define EVAL_RADIUS_EXPR(comp)                                          \

+    expr = boxblur->comp##_radius_expr;                                 \

+    ret = av_expr_parse_and_eval(&res, expr, var_names, var_values,     \

+                                 NULL, NULL, NULL, NULL, NULL, 0, ctx); \

+    boxblur->comp##_param.radius = res;                                 \

+    if (ret < 0) {                                                      \

+        av_log(NULL, AV_LOG_ERROR,                                      \

+               "Error when evaluating " #comp " radius expression '%s'\n", expr); \

+        return ret;                                                     \

+    }

+    EVAL_RADIUS_EXPR(luma);

+    EVAL_RADIUS_EXPR(chroma);

+    EVAL_RADIUS_EXPR(alpha);

+

+    av_log(ctx, AV_LOG_INFO,

+           "luma_radius:%d luma_power:%d "

+           "chroma_radius:%d chroma_power:%d "

+           "alpha_radius:%d alpha_power:%d "

+           "w:%d chroma_w:%d h:%d chroma_h:%d\n",

+           boxblur->luma_param  .radius, boxblur->luma_param  .power,

+           boxblur->chroma_param.radius, boxblur->chroma_param.power,

+           boxblur->alpha_param .radius, boxblur->alpha_param .power,

+           w, cw, h, ch);

+

+#define CHECK_RADIUS_VAL(w_, h_, comp)                                  \

+    if (boxblur->comp##_param.radius < 0 ||                             \

+        2*boxblur->comp##_param.radius > FFMIN(w_, h_)) {               \

+        av_log(ctx, AV_LOG_ERROR,                                       \

+               "Invalid " #comp " radius value %d, must be >= 0 and <= %d\n", \

+               boxblur->comp##_param.radius, FFMIN(w_, h_)/2);          \

+        return AVERROR(EINVAL);                                         \

+    }

+    CHECK_RADIUS_VAL(w,  h,  luma);

+    CHECK_RADIUS_VAL(cw, ch, chroma);

+    CHECK_RADIUS_VAL(w,  h,  alpha);

+

+    boxblur->radius[Y] = boxblur->luma_param.radius;

+    boxblur->radius[U] = boxblur->radius[V] = boxblur->chroma_param.radius;

+    boxblur->radius[A] = boxblur->alpha_param.radius;

+

+    boxblur->power[Y] = boxblur->luma_param.power;

+    boxblur->power[U] = boxblur->power[V] = boxblur->chroma_param.power;

+    boxblur->power[A] = boxblur->alpha_param.power;

+

+    return 0;

+}

+

+static inline void blur(uint8_t *dst, int dst_step, const uint8_t *src, int src_step,

+                        int w, int radius)

+{

+    /* Naive boxblur would sum source pixels from x-radius .. x+radius

+     * for destination pixel x. That would be O(radius*width).

+     * If you now look at what source pixels represent 2 consecutive

+     * output pixels, then you see they are almost identical and only

+     * differ by 2 pixels, like:

+     * src0       111111111

+     * dst0           1

+     * src1        111111111

+     * dst1            1

+     * src0-src1  1       -1

+     * so when you know one output pixel you can find the next by just adding

+     * and subtracting 1 input pixel.

+     * The following code adopts this faster variant.

+     */

+    int x, sum = 0;

+    const int length = radius*2 + 1;

+    const int inv = ((1<<16) + length/2)/length;

+

+    for (x = 0; x < radius; x++)

+        sum += src[x*src_step]<<1;

+    sum += src[radius*src_step];

+

+    for (x = 0; x <= radius; x++) {

+        sum += src[(radius+x)*src_step] - src[(radius-x)*src_step];

+        dst[x*dst_step] = (sum*inv + (1<<15))>>16;

+    }

+

+    for (; x < w-radius; x++) {

+        sum += src[(radius+x)*src_step] - src[(x-radius-1)*src_step];

+        dst[x*dst_step] = (sum*inv + (1<<15))>>16;

+    }

+

+    for (; x < w; x++) {

+        sum += src[(2*w-radius-x-1)*src_step] - src[(x-radius-1)*src_step];

+        dst[x*dst_step] = (sum*inv + (1<<15))>>16;

+    }

+}

+

+static inline void blur_power(uint8_t *dst, int dst_step, const uint8_t *src, int src_step,

+                              int w, int radius, int power, uint8_t *temp[2])

+{

+    uint8_t *a = temp[0], *b = temp[1];

+

+    if (radius && power) {

+        blur(a, 1, src, src_step, w, radius);

+        for (; power > 2; power--) {

+            uint8_t *c;

+            blur(b, 1, a, 1, w, radius);

+            c = a; a = b; b = c;

+        }

+        if (power > 1) {

+            blur(dst, dst_step, a, 1, w, radius);

+        } else {

+            int i;

+            for (i = 0; i < w; i++)

+                dst[i*dst_step] = a[i];

+        }

+    } else {

+        int i;

+        for (i = 0; i < w; i++)

+            dst[i*dst_step] = src[i*src_step];

+    }

+}

+

+static void hblur(uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize,

+                  int w, int h, int radius, int power, uint8_t *temp[2])

+{

+    int y;

+

+    if (radius == 0 && dst == src)

+        return;

+

+    for (y = 0; y < h; y++)

+        blur_power(dst + y*dst_linesize, 1, src + y*src_linesize, 1,

+                   w, radius, power, temp);

+}

+

+static void vblur(uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize,

+                  int w, int h, int radius, int power, uint8_t *temp[2])

+{

+    int x;

+

+    if (radius == 0 && dst == src)

+        return;

+

+    for (x = 0; x < w; x++)

+        blur_power(dst + x, dst_linesize, src + x, src_linesize,

+                   h, radius, power, temp);

+}

+

+static void draw_slice(AVFilterLink *inlink, int y0, int h0, int slice_dir)

+{

+    AVFilterContext *ctx = inlink->dst;

+    BoxBlurContext *boxblur = ctx->priv;

+    AVFilterLink *outlink = inlink->dst->outputs[0];

+    AVFilterBufferRef *inpicref  = inlink ->cur_buf;

+    AVFilterBufferRef *outpicref = outlink->out_buf;

+    int plane;

+    int cw = inlink->w >> boxblur->hsub, ch = h0 >> boxblur->vsub;

+    int w[4] = { inlink->w, cw, cw, inlink->w };

+    int h[4] = { h0, ch, ch, h0 };

+    uint8_t *dst[4], *src[4];

+

+    for (plane = 0; inpicref->data[plane] && plane < 4; plane++) {

+        int y = plane == 1 || plane == 2 ? y0 >> boxblur->vsub : y0;

+        src[plane] = inpicref ->data[plane] + inpicref ->linesize[plane] * y;

+        dst[plane] = outpicref->data[plane] + outpicref->linesize[plane] * y;

+    }

+

+    for (plane = 0; inpicref->data[plane] && plane < 4; plane++)

+        hblur(outpicref->data[plane], outpicref->linesize[plane],

+              inpicref ->data[plane], inpicref ->linesize[plane],

+              w[plane], h[plane], boxblur->radius[plane], boxblur->power[plane],

+              boxblur->temp);

+

+    for (plane = 0; inpicref->data[plane] && plane < 4; plane++)

+        vblur(outpicref->data[plane], outpicref->linesize[plane],

+              outpicref->data[plane], outpicref->linesize[plane],

+              w[plane], h[plane], boxblur->radius[plane], boxblur->power[plane],

+              boxblur->temp);

+}

+

+AVFilter avfilter_vf_boxblur = {

+    .name          = "boxblur",

+    .description   = NULL_IF_CONFIG_SMALL("Blur the input."),

+    .priv_size     = sizeof(BoxBlurContext),

+    .init          = init,

+    .uninit        = uninit,

+    .query_formats = query_formats,

+

+    .inputs    = (AVFilterPad[]) {{ .name             = "default",

+                                    .type             = AVMEDIA_TYPE_VIDEO,

+                                    .config_props     = config_input,

+                                    .draw_slice       = draw_slice,

+                                    .min_perms        = AV_PERM_READ },

+                                  { .name = NULL}},

+    .outputs   = (AVFilterPad[]) {{ .name             = "default",

+                                    .type             = AVMEDIA_TYPE_VIDEO, },

+                                  { .name = NULL}},

+};