From 17dcc0658d75770192c1fd660d24dff8fc48f84d Mon Sep 17 00:00:00 2001 From: Paul B Mahol Date: Mon, 12 Aug 2019 09:20:08 +0200 Subject: [PATCH] avfilter: add sierpinski video source --- libavfilter/Makefile | 1 + libavfilter/allfilters.c | 1 + libavfilter/vsrc_sierpinski.c | 172 ++++++++++++++++++++++++++++++++++ 3 files changed, 174 insertions(+) create mode 100644 libavfilter/vsrc_sierpinski.c diff --git a/libavfilter/Makefile b/libavfilter/Makefile index b5d48ff9a3..5ba443e43f 100644 --- a/libavfilter/Makefile +++ b/libavfilter/Makefile @@ -451,6 +451,7 @@ OBJS-$(CONFIG_OPENCLSRC_FILTER) += vf_program_opencl.o opencl.o OBJS-$(CONFIG_PAL75BARS_FILTER) += vsrc_testsrc.o OBJS-$(CONFIG_PAL100BARS_FILTER) += vsrc_testsrc.o OBJS-$(CONFIG_RGBTESTSRC_FILTER) += vsrc_testsrc.o +OBJS-$(CONFIG_SIERPINSKI_FILTER) += vsrc_sierpinski.o OBJS-$(CONFIG_SMPTEBARS_FILTER) += vsrc_testsrc.o OBJS-$(CONFIG_SMPTEHDBARS_FILTER) += vsrc_testsrc.o OBJS-$(CONFIG_TESTSRC_FILTER) += vsrc_testsrc.o diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c index 5d4cec2119..031c8a71f2 100644 --- a/libavfilter/allfilters.c +++ b/libavfilter/allfilters.c @@ -430,6 +430,7 @@ extern AVFilter ff_vsrc_openclsrc; extern AVFilter ff_vsrc_pal75bars; extern AVFilter ff_vsrc_pal100bars; extern AVFilter ff_vsrc_rgbtestsrc; +extern AVFilter ff_vsrc_sierpinski; extern AVFilter ff_vsrc_smptebars; extern AVFilter ff_vsrc_smptehdbars; extern AVFilter ff_vsrc_testsrc; diff --git a/libavfilter/vsrc_sierpinski.c b/libavfilter/vsrc_sierpinski.c new file mode 100644 index 0000000000..20c64df7d0 --- /dev/null +++ b/libavfilter/vsrc_sierpinski.c @@ -0,0 +1,172 @@ +/* + * Copyright (c) 2019 Paul B Mahol + * + * 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 + * Sierpinski carpet fractal renderer + */ + +#include "avfilter.h" +#include "formats.h" +#include "video.h" +#include "internal.h" +#include "libavutil/imgutils.h" +#include "libavutil/intreadwrite.h" +#include "libavutil/opt.h" +#include "libavutil/parseutils.h" +#include +#include + +typedef struct SierpinskiContext { + const AVClass *class; + int w, h; + AVRational frame_rate; + uint64_t pts; + + float scale; +} SierpinskiContext; + +#define OFFSET(x) offsetof(SierpinskiContext, x) +#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM + +static const AVOption sierpinski_options[] = { + {"size", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, 0, 0, FLAGS }, + {"s", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, 0, 0, FLAGS }, + {"rate", "set frame rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, 0, FLAGS }, + {"r", "set frame rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, 0, FLAGS }, + {NULL}, +}; + +AVFILTER_DEFINE_CLASS(sierpinski); + +static int query_formats(AVFilterContext *ctx) +{ + static const enum AVPixelFormat pix_fmts[] = { + AV_PIX_FMT_0BGR32, + AV_PIX_FMT_NONE + }; + + 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_output(AVFilterLink *inlink) +{ + AVFilterContext *ctx = inlink->src; + SierpinskiContext *s = ctx->priv; + + if (av_image_check_size(s->w, s->h, 0, ctx) < 0) + return AVERROR(EINVAL); + + inlink->w = s->w; + inlink->h = s->h; + inlink->time_base = av_inv_q(s->frame_rate); + inlink->sample_aspect_ratio = (AVRational) {1, 1}; + + return 0; +} + +static int fill_sierpinski(SierpinskiContext *s, int x, int y) +{ + float pos_x = x - s->w / 2.f; + float pos_y = y - s->h / 2.f; + float offset_x = -0.5f; + float offset_y = -0.5f; + float scale = s->scale; + float size = s->h * scale; + + pos_x += offset_x * s->h * (scale * .5f - .5f); + pos_y += offset_y * s->h * (scale * .5f - .5f); + + while (size > 1.f) { + int ip_x, ip_y; + + size /= 3.f; + ip_x = roundf(pos_x / size); + ip_y = roundf(pos_y / size); + + if (ip_x == 0 && ip_y == 0) { + return size; + } else { + pos_x -= ip_x * size; + pos_y -= ip_y * size; + } + } + + return 0; +} + +static void draw_sierpinski(AVFilterContext *ctx, AVFrame *frame) +{ + SierpinskiContext *s = ctx->priv; + uint8_t *dst = frame->data[0]; + float t = frame->pts / (av_q2d(s->frame_rate) * 5); + + s->scale = powf(3.f, fmodf(t, 2.f) + 1.f); + + for (int y = 0; y < frame->height; y++) { + for (int x = 0; x < frame->width; x++) { + if (fill_sierpinski(s, x, y)) { + AV_WL32(&dst[x*4], 0xffffffff); + } else { + AV_WL32(&dst[x*4], 0x00000000); + } + } + dst += frame->linesize[0]; + } +} + +static int sierpinski_request_frame(AVFilterLink *link) +{ + SierpinskiContext *s = link->src->priv; + AVFrame *frame = ff_get_video_buffer(link, s->w, s->h); + + if (!frame) + return AVERROR(ENOMEM); + + frame->sample_aspect_ratio = (AVRational) {1, 1}; + frame->pts = s->pts++; + + draw_sierpinski(link->src, frame); + + return ff_filter_frame(link, frame); +} + +static const AVFilterPad sierpinski_outputs[] = { + { + .name = "default", + .type = AVMEDIA_TYPE_VIDEO, + .request_frame = sierpinski_request_frame, + .config_props = config_output, + }, + { NULL } +}; + +AVFilter ff_vsrc_sierpinski = { + .name = "sierpinski", + .description = NULL_IF_CONFIG_SMALL("Render a Sierpinski carpet fractal."), + .priv_size = sizeof(SierpinskiContext), + .priv_class = &sierpinski_class, + .query_formats = query_formats, + .inputs = NULL, + .outputs = sierpinski_outputs, +}; -- 2.22.0