[FFmpeg-devel] [PATCH V1] lavfi/superfastblur: add superfastblur filter
Steven Liu
lq at chinaffmpeg.org
Tue Nov 12 11:08:04 EET 2019
> 在 2019年11月12日，15:51，Jun Zhao <mypopydev at gmail.com> 写道：
>
> From: Jun Zhao <barryjzhao at tencent.com>
>
> add superfastblur filter
>
> Signed-off-by: Jun Zhao <barryjzhao at tencent.com>
> ---
> doc/filters.texi | 15 ++
> libavfilter/Makefile | 1 +
> libavfilter/allfilters.c | 1 +
> libavfilter/vf_superfastblur.c | 275 ++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 292 insertions(+), 0 deletions(-)
> create mode 100644 libavfilter/vf_superfastblur.c
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 6800124..c7d1893 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -17453,6 +17453,21 @@ Interpolate) pixel art scaling algorithm.
>
> Useful for enlarging pixel art images without reducing sharpness.
>
> + at section superfastblur
> +
> +Blur the input image with super fast blur algorithm, multiple invocations of this
> +filter with a small radius will approximate a gaussian blur quite well.
> +
> +This filter accepts the following options:
> +
> + at table @option
> + at item radius
> + at item r
> +Set the blurring box radius. The option value must be a int number in
> +the range [1, 10] that specifies the blur box size of the superfast blur filter
> +used to blur the image. Default value is @code{2}..
> + at end table
> +
> @section swaprect
>
> Swap two rectangular objects in video.
> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
> index fce9303..db4d5e6 100644
> --- a/libavfilter/Makefile
> +++ b/libavfilter/Makefile
> @@ -396,6 +396,7 @@ OBJS-$(CONFIG_STEREO3D_FILTER) += vf_stereo3d.o
> OBJS-$(CONFIG_STREAMSELECT_FILTER) += f_streamselect.o framesync.o
> OBJS-$(CONFIG_SUBTITLES_FILTER) += vf_subtitles.o
> OBJS-$(CONFIG_SUPER2XSAI_FILTER) += vf_super2xsai.o
> +OBJS-$(CONFIG_SUPEREQUALIZER_FILTER) += vf_superfastblur.o
> OBJS-$(CONFIG_SWAPRECT_FILTER) += vf_swaprect.o
> OBJS-$(CONFIG_SWAPUV_FILTER) += vf_swapuv.o
> OBJS-$(CONFIG_TBLEND_FILTER) += vf_blend.o framesync.o
> diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
> index 7c1e19e..d507bc5 100644
> --- a/libavfilter/allfilters.c
> +++ b/libavfilter/allfilters.c
> @@ -377,6 +377,7 @@ extern AVFilter ff_vf_stereo3d;
> extern AVFilter ff_vf_streamselect;
> extern AVFilter ff_vf_subtitles;
> extern AVFilter ff_vf_super2xsai;
> +extern AVFilter ff_vf_superfastblur;
> extern AVFilter ff_vf_swaprect;
> extern AVFilter ff_vf_swapuv;
> extern AVFilter ff_vf_tblend;
> diff --git a/libavfilter/vf_superfastblur.c b/libavfilter/vf_superfastblur.c
> new file mode 100644
> index 0000000..a6428cf
> --- /dev/null
> +++ b/libavfilter/vf_superfastblur.c
> @@ -0,0 +1,275 @@
> +/*
> + * Copyright (c) 2019 Jun Zhao
> + *
> + * 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
> + * Super fast blur filter
> + *
> + * @see http://incubator.quasimondo.com/processing/superfast_blur.php
> + */
> +
> +#include "libavutil/avassert.h"
> +#include "libavutil/imgutils.h"
> +#include "libavutil/opt.h"
> +#include "avfilter.h"
> +#include "formats.h"
> +#include "internal.h"
> +#include "video.h"
> +
> +typedef struct SuperFastBlurContext {
> + const AVClass *class;
> +
> + int radius;
> +
> + uint32_t *vMIN;
> + uint32_t *vMAX;
> +
> + uint8_t *r;
> + uint8_t *g;
> + uint8_t *b;
> +
> + uint8_t *dv;
> +} SuperFastBlurContext;
> +
> +#define OFFSET(x) offsetof(SuperFastBlurContext, x)
> +#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
> +static const AVOption superfastblur_options[] = {
> + { "radius", "Radius of the super fast blurring box", OFFSET(radius), AV_OPT_TYPE_INT, {.i64 = 2}, 1, 10, FLAGS },
> + { "r", "Radius of the super fast blurring box", OFFSET(radius), AV_OPT_TYPE_INT, {.i64 = 2}, 1, 10, FLAGS },
> + { NULL }
> +};
> +
> +AVFILTER_DEFINE_CLASS(superfastblur);
> +
> +static av_cold int init(AVFilterContext *ctx)
> +{
> + SuperFastBlurContext *s = ctx->priv;
> +
> + // This line precalculates a lookup table for all the possible
> + // mean values that can occur. This is to avoid costly division
> + // in the inner loop. On some systems doing the division directly
> + // instead of a doing an array lookup might actually be faster
> + // nowadays.
> + uint32_t div = 2 * s->radius + 1;
> + s->dv = av_malloc(sizeof(*s->dv) * 256 * div);
> + if (!s->dv)
> + return AVERROR(ENOMEM);
> + for (int i = 0; i < 256 * div; i++)
> + s->dv[i] = (i / div);
> +
> + return 0;
> +}
> +
> +static int query_formats(AVFilterContext *ctx)
> +{
> + static const enum AVPixelFormat pix_fmts[] = {
> + AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
> +
> + AV_PIX_FMT_NONE
Empty line？
> + };
> +
> + 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_props(AVFilterLink *inlink)
> +{
> + AVFilterContext *ctx = inlink->dst;
> + SuperFastBlurContext *s = ctx->priv;
> +
> + uint32_t wm = inlink->w - 1;
> + uint32_t wh = inlink->w * inlink->h;
> +
> + s->vMIN = av_malloc(sizeof(wm) * FFMAX(inlink->w, inlink->h));
> + s->vMAX = av_malloc(sizeof(wm) * FFMAX(inlink->w, inlink->h));
> + s->r = av_malloc(sizeof(*s->r) * wh);
> + s->g = av_malloc(sizeof(*s->g) * wh);
> + s->b = av_malloc(sizeof(*s->b) * wh);
> +
> + if (!s->vMIN || !s->vMAX || !s->r || !s->g || !s->b)
> + return AVERROR(ENOMEM);
> +
> + return 0;
> +}
> +
> +/*
> + * Super Fast Blur v1.1+
> + * by Mario Klingemann <http://incubator.quasimondo.com>
> + * Original address: http://incubator.quasimondo.com/processing/superfastblur.pde
> + *
> + * Tip: Multiple invocations of this filter with a small
> + * radius will approximate a gaussian blur quite well.
> + */
> +static void superfast_blur(SuperFastBlurContext *s, uint8_t *pix, int w, int h, int nb_comps)
> +{
> + uint32_t wm, hm;
> + uint32_t *vMIN, *vMAX;
> + uint8_t *r, *g, *b, *dv;
> + uint32_t rsum, gsum, bsum;
> + uint32_t p, p1, p2, yi, yw;
> +
> + int radius;
> +
> + int x, y, i, yp;
> +
> + wm = w - 1;
> + hm = h - 1;
> +
> + vMIN = s->vMIN;
> + vMAX = s->vMAX;
> + r = s->r;
> + g = s->g;
> + b = s->b;
> +
> + dv = s->dv;
> +
> + radius = s->radius;
> +
> + yw = yi = 0;
> + for (y = 0; y < h; y++) {
> + rsum = gsum = bsum = 0;
> + // The reason why this algorithm is fast is that it uses a sliding
> + // window and thus reduces the number of required pixel lookups.
> + // The window slides from the left edge to the right (and in the
> + // second pass from top to bottom) and only adds one pixel at the
> + // right and removes one from the left. The code above initializes
> + // the window by prefilling the window with the leftmost edge pixel
> + // depending on the kernel size.
> + for (i = -radius; i <= radius; i++) {
> + p = (yi + FFMIN(wm, FFMAX(i, 0))) * nb_comps;
> + rsum += pix[p];
> + gsum += pix[p + 1];
> + bsum += pix[p + 2];
> + }
> +
> + for (x = 0; x < w; x++) {
> + r[yi] = dv[rsum];
> + g[yi] = dv[gsum];
> + b[yi] = dv[bsum];
> +
> + // adds a new pixel but at the same time handles the border
> + // conditions (when the window tries to read or remove pixels
> + // outside the bitmap).
> + if (y == 0) {
> + vMIN[x] = FFMIN(x + radius + 1, wm);
> + vMAX[x] = FFMAX(x - radius, 0);
> + }
> + p1 = (yw + vMIN[x]) * nb_comps;
> + p2 = (yw + vMAX[x]) * nb_comps;
> + rsum += pix[p1] - pix[p2];
> + gsum += pix[p1 + 1] - pix[p2 + 1];
> + bsum += pix[p1 + 2] - pix[p2 + 2];
> + yi++;
> + }
> + yw += w;
> + }
> +
> + for (x = 0; x < w; x++) {
> + rsum = gsum = bsum = 0;
> + yp = -radius * w;
> + for (i = -radius; i <= radius; i++) {
> + yi = FFMAX(0, yp) + x;
> + rsum += r[yi];
> + gsum += g[yi];
> + bsum += b[yi];
> + yp += w;
> + }
> +
> + yi = x;
> + for (y = 0; y < h; y++) {
> + pix[yi * nb_comps] = dv[bsum];
> + pix[yi * nb_comps + 1] = dv[gsum];
> + pix[yi * nb_comps + 2] = dv[rsum];
> +
> + if (x == 0) {
> + vMIN[y] = FFMIN(y + radius + 1, hm) * w;
> + vMAX[y] = FFMAX(y - radius, 0) * w;
> + }
> + p1 = x + vMIN[y];
> + p2 = x + vMAX[y];
> +
> + // rsum, gsum and bsum is the accumulated sum of pixels inside
> + // the sliding window. What you see is the new pixel on the
> + // right side being added to the sum and the leftmost pixel
> + // i nthe window being removed from the sum.
> + rsum += r[p1] - r[p2];
> + gsum += g[p1] - g[p2];
> + bsum += b[p1] - b[p2];
> + yi += w;
> + }
> + }
> +}
> +
> +static int filter_frame(AVFilterLink *inlink, AVFrame *in)
> +{
> + AVFilterContext *ctx = inlink->dst;
> + SuperFastBlurContext *s = ctx->priv;
> + AVFilterLink *outlink = ctx->outputs[0];
> + const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
> +
> + superfast_blur(s, in->data[0], inlink->w, inlink->h, desc->nb_components);
> +
> + return ff_filter_frame(outlink, in);
> +}
> +
> +static av_cold void uninit(AVFilterContext *ctx)
> +{
> + SuperFastBlurContext *s = ctx->priv;
> +
> + av_freep(&s->r);
> + av_freep(&s->g);
> + av_freep(&s->b);
> + av_freep(&s->vMIN);
> + av_freep(&s->vMAX);
> + av_freep(&s->dv);
> +}
> +
> +static const AVFilterPad superfastblur_inputs[] = {
> + {
> + .name = "default",
> + .type = AVMEDIA_TYPE_VIDEO,
> + .config_props = config_props,
> + .filter_frame = filter_frame,
> + },
> + { NULL }
> +};
> +
> +static const AVFilterPad superfastblur_outputs[] = {
> + {
> + .name = "default",
> + .type = AVMEDIA_TYPE_VIDEO,
> + },
> + { NULL }
> +};
> +
> +AVFilter ff_vf_superfastblur = {
> + .name = "superfastblur",
> + .description = NULL_IF_CONFIG_SMALL("Blur the input with super fast blur algorithm."),
> + .priv_size = sizeof(SuperFastBlurContext),
> + .init = init,
> + .uninit = uninit,
> + .query_formats = query_formats,
> + .inputs = superfastblur_inputs,
> + .outputs = superfastblur_outputs,
> + .priv_class = &superfastblur_class,
> + .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
> +};
> --
> 1.7.1
>
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LGTM
BTW, I saw you usually submit multi thread performance optimization for other filter,
Why don’y do that in this filter one time complete?
I think maybe only one patch complete the whole operation maybe better.
Thanks
Steven
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