Hi, still missing documentation and might be optimized (and maybe extended to support gray16 - this should be simple), comments are welcome.
>From 5018f5b887ef84c19cbf3f76c6607b49a6c99f2a Mon Sep 17 00:00:00 2001 From: Stefano Sabatini <stefa...@gmail.com> Date: Mon, 27 May 2024 11:19:08 +0200 Subject: [PATCH] lavfi: add perlin noise generator
--- libavfilter/Makefile | 1 + libavfilter/allfilters.c | 1 + libavfilter/perlin.c | 221 ++++++++++++++++++++++++++++++++++++++ libavfilter/perlin.h | 52 +++++++++ libavfilter/vsrc_perlin.c | 170 +++++++++++++++++++++++++++++ 5 files changed, 445 insertions(+) create mode 100644 libavfilter/perlin.c create mode 100644 libavfilter/perlin.h create mode 100644 libavfilter/vsrc_perlin.c diff --git a/libavfilter/Makefile b/libavfilter/Makefile index 5992fd161f..63088e9286 100644 --- a/libavfilter/Makefile +++ b/libavfilter/Makefile @@ -603,6 +603,7 @@ OBJS-$(CONFIG_NULLSRC_FILTER) += vsrc_testsrc.o OBJS-$(CONFIG_OPENCLSRC_FILTER) += vf_program_opencl.o opencl.o OBJS-$(CONFIG_PAL75BARS_FILTER) += vsrc_testsrc.o OBJS-$(CONFIG_PAL100BARS_FILTER) += vsrc_testsrc.o +OBJS-$(CONFIG_PERLIN_FILTER) += vsrc_perlin.o perlin.o OBJS-$(CONFIG_QRENCODE_FILTER) += qrencode.o textutils.o OBJS-$(CONFIG_QRENCODESRC_FILTER) += qrencode.o textutils.o OBJS-$(CONFIG_RGBTESTSRC_FILTER) += vsrc_testsrc.o diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c index c532682fc2..63600e9b58 100644 --- a/libavfilter/allfilters.c +++ b/libavfilter/allfilters.c @@ -569,6 +569,7 @@ extern const AVFilter ff_vsrc_openclsrc; extern const AVFilter ff_vsrc_qrencodesrc; extern const AVFilter ff_vsrc_pal75bars; extern const AVFilter ff_vsrc_pal100bars; +extern const AVFilter ff_vsrc_perlin; extern const AVFilter ff_vsrc_rgbtestsrc; extern const AVFilter ff_vsrc_sierpinski; extern const AVFilter ff_vsrc_smptebars; diff --git a/libavfilter/perlin.c b/libavfilter/perlin.c new file mode 100644 index 0000000000..07a7cc18ea --- /dev/null +++ b/libavfilter/perlin.c @@ -0,0 +1,221 @@ +/* + * 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 + * Perlin Noise generator, based on code from: + * https://adrianb.io/2014/08/09/perlinnoise.html + * + * Original article from Ken Perlin: + * http://mrl.nyu.edu/~perlin/paper445.pdf + */ + +#include <math.h> + +#include "libavutil/lfg.h" +#include "libavutil/random_seed.h" +#include "perlin.h" + +static inline int inc(int num, int period) +{ + num++; + if (period > 0) + num %= period; + return num; +} + +static inline double grad(int hash, double x, double y, double z) +{ + // Take the hashed value and take the first 4 bits of it (15 == 0b1111) + int h = hash & 15; + // If the most significant bit (MSB) of the hash is 0 then set u = x. Otherwise y. + double u = h < 8 /* 0b1000 */ ? x : y; + double v; + + // In Ken Perlin's original implementation this was another + // conditional operator (?:), then expanded for readability. + if (h < 4 /* 0b0100 */) + // If the first and second significant bits are 0 set v = y + v = y; + // If the first and second significant bits are 1 set v = x + else if (h == 12 /* 0b1100 */ || h == 14 /* 0b1110*/) + v = x; + else + // If the first and second significant bits are not equal (0/1, 1/0) set v = z + v = z; + + // Use the last 2 bits to decide if u and v are positive or negative. Then return their addition. + return ((h&1) == 0 ? u : -u)+((h&2) == 0 ? v : -v); +} + +static inline double fade(double t) +{ + // Fade function as defined by Ken Perlin. This eases coordinate values + // so that they will "ease" towards integral values. This ends up smoothing + // the final output. + return t * t * t * (t * (t * 6 - 15) + 10); // 6t^5 - 15t^4 + 10t^3 +} + +static double lerp(double a, double b, double x) +{ + return a + x * (b - a); +} + +// Hash lookup table as defined by Ken Perlin. This is a randomly +// arranged array of all numbers from 0-255 inclusive. +static uint8_t ken_permutations[] = { + 151, 160, 137, 91, 90, 15, 131, 13, 201, 95, 96, 53, 194, 233, 7, 225, + 140, 36, 103, 30, 69, 142, 8, 99, 37, 240, 21, 10, 23, 190, 6, 148, + 247, 120, 234, 75, 0, 26, 197, 62, 94, 252, 219, 203, 117, 35, 11, 32, + 57, 177, 33, 88, 237, 149, 56, 87, 174, 20, 125, 136, 171, 168, 68, 175, + 74, 165, 71, 134, 139, 48, 27, 166, 77, 146, 158, 231, 83, 111, 229, 122, + 60, 211, 133, 230, 220, 105, 92, 41, 55, 46, 245, 40, 244, 102, 143, 54, + 65, 25, 63, 161, 1, 216, 80, 73, 209, 76, 132, 187, 208, 89, 18, 169, + 200, 196, 135, 130, 116, 188, 159, 86, 164, 100, 109, 198, 173, 186, 3, 64, + 52, 217, 226, 250, 124, 123, 5, 202, 38, 147, 118, 126, 255, 82, 85, 212, + 207, 206, 59, 227, 47, 16, 58, 17, 182, 189, 28, 42, 223, 183, 170, 213, + 119, 248, 152, 2, 44, 154, 163, 70, 221, 153, 101, 155, 167, 43, 172, 9, + 129, 22, 39, 253, 19, 98, 108, 110, 79, 113, 224, 232, 178, 185, 112, 104, + 218, 246, 97, 228, 251, 34, 242, 193, 238, 210, 144, 12, 191, 179, 162, 241, + 81, 51, 145, 235, 249, 14, 239, 107, 49, 192, 214, 31, 181, 199, 106, 157, + 184, 84, 204, 176, 115, 121, 50, 45, 127, 4, 150, 254, 138, 236, 205, 93, + 222, 114, 67, 29, 24, 72, 243, 141, 128, 195, 78, 66, 215, 61, 156, 180 +}; + +int ff_perlin_init(FFPerlin *perlin, int period, int octaves, double persistence, + enum FFPerlinRandomMode random_mode, unsigned int random_seed) +{ + int i; + + /* todo: perform validation? */ + perlin->period = period; + perlin->octaves = octaves; + perlin->persistence = persistence; + perlin->random_mode = random_mode; + perlin->random_seed = random_seed; + + if (perlin->random_mode == FF_PERLIN_RANDOM_MODE_KEN) { + for (i = 0; i < 512; i++) { + perlin->permutations[i] = ken_permutations[i % 256]; + } + } else { + AVLFG lfg; + uint8_t random_permutations[256]; + + if (perlin->random_mode == FF_PERLIN_RANDOM_MODE_RANDOM) + perlin->random_seed = av_get_random_seed(); + + av_lfg_init(&lfg, perlin->random_seed); + + for (i = 0; i < 256; i++) { + random_permutations[i] = i; + } + + for (i = 0; i < 256; i++) { + unsigned int random_idx = av_lfg_get(&lfg) % (256-i); + uint8_t random_val = random_permutations[random_idx]; + random_permutations[random_idx] = random_permutations[256-i]; + + perlin->permutations[i] = perlin->permutations[i+256] = random_val; + } + } + + return 0; +} + +static double perlin_get(FFPerlin *perlin, double x, double y, double z) +{ + if (perlin->period > 0) { + // If we have any period on, change the coordinates to their "local" repetitions + x = fmod(x, perlin->period); + y = fmod(y, perlin->period); + z = fmod(z, perlin->period); + } + + // Calculate the "unit cube" that the point asked will be located in + // The left bound is ( |_x_|,|_y_|,|_z_| ) and the right bound is that + // plus 1. Next we calculate the location (from 0.0 to 1.0) in that cube. + int xi = (int)x & 255; + int yi = (int)y & 255; + int zi = (int)z & 255; + + double xf = x - (int)x; + double yf = y - (int)y; + double zf = z - (int)z; + + // We also fade the location to smooth the result. + double u = fade(xf); + double v = fade(yf); + double w = fade(zf); + + const uint8_t *p = perlin->permutations; + int period = perlin->period; + + int aaa, aba, aab, abb, baa, bba, bab, bbb; + aaa = p[p[p[ xi ] + yi ] + zi ]; + aba = p[p[p[ xi ] + inc(yi, period)] + zi ]; + aab = p[p[p[ xi ] + yi ] + inc(zi, period)]; + abb = p[p[p[ xi ] + inc(yi, period)] + inc(zi, period)]; + baa = p[p[p[inc(xi, period)] + yi ] + zi ]; + bba = p[p[p[inc(xi, period)] + inc(yi, period)] + zi ]; + bab = p[p[p[inc(xi, period)] + yi ] + inc(zi, period)]; + bbb = p[p[p[inc(xi, period)] + inc(yi, period)] + inc(zi, period)]; + + double x1, x2, y1, y2; + // The gradient function calculates the dot product between a pseudorandom + // gradient vector and the vector from the input coordinate to the 8 + // surrounding points in its unit cube. + // This is all then lerped together as a sort of weighted average based on the faded (u,v,w) + // values we made earlier. + x1 = lerp(grad(aaa, xf , yf , zf), + grad(baa, xf-1, yf , zf), + u); + x2 = lerp(grad(aba, xf , yf-1, zf), + grad(bba, xf-1, yf-1, zf), + u); + y1 = lerp(x1, x2, v); + + x1 = lerp(grad(aab, xf , yf , zf-1), + grad(bab, xf-1, yf , zf-1), + u); + x2 = lerp(grad(abb, xf , yf-1, zf-1), + grad(bbb, xf-1, yf-1, zf-1), + u); + y2 = lerp(x1, x2, v); + + // For convenience we bound it to 0 - 1 (theoretical min/max before is -1 - 1) + return (lerp(y1, y2, w) + 1) / 2; +} + +double ff_perlin_get(FFPerlin *perlin, double x, double y, double z) +{ + double total = 0; + double frequency = 1; + double amplitude = 1; + double max_value = 0; // Used for normalizing result to 0.0 - 1.0 + + for (int i = 0; i < perlin->octaves; i++) { + total += perlin_get(perlin, x * frequency, y * frequency, z * frequency) * amplitude; + max_value += amplitude; + amplitude *= perlin->persistence; + frequency *= 2; + } + + return total / max_value; +} + diff --git a/libavfilter/perlin.h b/libavfilter/perlin.h new file mode 100644 index 0000000000..542ee1f484 --- /dev/null +++ b/libavfilter/perlin.h @@ -0,0 +1,52 @@ +/* + * Perlin noise generator + * + * 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 + * Perlin Noise generator + */ + +#ifndef AVFILTER_PERLIN_H +#define AVFILTER_PERLIN_H + +#include <stdint.h> + +enum FFPerlinRandomMode { + FF_PERLIN_RANDOM_MODE_RANDOM, + FF_PERLIN_RANDOM_MODE_KEN, + FF_PERLIN_RANDOM_MODE_SEED, + FF_PERLIN_RANDOM_MODE_NB +}; + +typedef struct FFPerlin { + int period; + int octaves; + double persistence; + uint8_t permutations[512]; + unsigned int random_seed; + enum FFPerlinRandomMode random_mode; +} FFPerlin; + +int ff_perlin_init(FFPerlin *perlin, int period, int octaves, double persistence, + enum FFPerlinRandomMode random_mode, unsigned int random_seed); + +double ff_perlin_get(FFPerlin *perlin, double x, double y, double z); + +#endif /* AVFILTER_PERLIN_H */ diff --git a/libavfilter/vsrc_perlin.c b/libavfilter/vsrc_perlin.c new file mode 100644 index 0000000000..f953b83a36 --- /dev/null +++ b/libavfilter/vsrc_perlin.c @@ -0,0 +1,170 @@ +/* + * 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 + * Perlin noise generator + */ + +#include <float.h> + +#include "perlin.h" +#include "libavutil/lfg.h" +#include "libavutil/opt.h" +#include "avfilter.h" +#include "internal.h" +#include "formats.h" +#include "video.h" + +typedef struct PerlinContext { + const AVClass *class; + + int w, h; + AVRational frame_rate; + + FFPerlin perlin; + int octaves; + double persistence; + unsigned int random_seed; + enum FFPerlinRandomMode random_mode; + + double xscale, yscale, tscale; + uint64_t pts; +} PerlinContext; + +#define OFFSET(x) offsetof(PerlinContext, x) +#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM + +static const AVOption perlin_options[] = { + { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "320x240"}, 0, 0, FLAGS }, + { "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "320x240"}, 0, 0, FLAGS }, + { "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, FLAGS }, + { "r", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, FLAGS }, + { "octaves", "set the number of components to use to generate the noise", OFFSET(octaves), AV_OPT_TYPE_INT, {.i64=1}, 1, INT_MAX, FLAGS }, + { "persistence", "set the octaves persistence", OFFSET(persistence), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, DBL_MAX, FLAGS }, + + { "xscale", "set x-scale factor", OFFSET(xscale), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, DBL_MAX, FLAGS }, + { "yscale", "set y-scale factor", OFFSET(yscale), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, DBL_MAX, FLAGS }, + { "tscale", "set t-scale factor", OFFSET(tscale), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, DBL_MAX, FLAGS }, + + { "random_mode", "set random mode", OFFSET(random_mode), AV_OPT_TYPE_INT, {.i64=FF_PERLIN_RANDOM_MODE_RANDOM}, 0, FF_PERLIN_RANDOM_MODE_NB-1, FLAGS, .unit = "random_mode" }, + { "random", "", 0, AV_OPT_TYPE_CONST, {.i64=FF_PERLIN_RANDOM_MODE_RANDOM}, 0, 0, FLAGS, .unit = "random_mode" }, + { "ken","", 0, AV_OPT_TYPE_CONST, {.i64=FF_PERLIN_RANDOM_MODE_KEN}, 0, 0, FLAGS, .unit = "random_mode" }, + { "seed", "", 0, AV_OPT_TYPE_CONST, {.i64=FF_PERLIN_RANDOM_MODE_SEED}, 0, 0, FLAGS, .unit = "random_mode" }, + + { "random_seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_UINT, {.i64=0}, 0, UINT_MAX, FLAGS }, + { "seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_UINT, {.i64=0}, 0, UINT_MAX, FLAGS }, + { NULL } +}; + +AVFILTER_DEFINE_CLASS(perlin); + +static av_cold int init(AVFilterContext *ctx) +{ + PerlinContext *perlin = ctx->priv; + int ret; + + if (ret = ff_perlin_init(&perlin->perlin, 0, perlin->octaves, perlin->persistence, + perlin->random_mode, perlin->random_seed)) { + return ret; + } + + av_log(ctx, AV_LOG_VERBOSE, + "s:%dx%d r:%d/%d octaves:%d persistence:%f xscale:%f yscale:%f tscale:%f\n", + perlin->w, perlin->h, perlin->frame_rate.num, perlin->frame_rate.den, + perlin->octaves, perlin->persistence, + perlin->xscale, perlin->yscale, perlin->tscale); + return 0; +} + +static int config_props(AVFilterLink *outlink) +{ + PerlinContext *perlin = outlink->src->priv; + + outlink->w = perlin->w; + outlink->h = perlin->h; + outlink->time_base = av_inv_q(perlin->frame_rate); + outlink->frame_rate = perlin->frame_rate; + + return 0; +} + +static int request_frame(AVFilterLink *outlink) +{ + AVFilterContext *ctx = outlink->src; + PerlinContext *perlin = ctx->priv; + AVFrame *picref = ff_get_video_buffer(outlink, perlin->w, perlin->h); + int i, j; + uint8_t *data0, *data; + double x, y, t; + + if (!picref) + return AVERROR(ENOMEM); + + picref->sample_aspect_ratio = (AVRational) {1, 1}; + picref->pts = perlin->pts++; + picref->duration = 1; + + t = perlin->tscale * (perlin->pts * av_q2d(outlink->time_base)); + data0 = picref->data[0]; + + for (i = 0; i < perlin->h; i++) { + y = perlin->yscale * (double)i / perlin->h; + + data = data0; + + for (j = 0; j < perlin->w; j++) { + double res; + x = perlin->xscale * (double)j / perlin->w; + res = ff_perlin_get(&perlin->perlin, x, y, t); + + //av_log(ctx, AV_LOG_VERBOSE, "(%f, %f, %f) => %f\n", x, y, z, res); + *data++ = res * 255; + } + data0 += picref->linesize[0]; + } + + return ff_filter_frame(outlink, picref); +} + +static int query_formats(AVFilterContext *ctx) +{ + enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE }; + + return ff_set_common_formats_from_list(ctx, pix_fmts); +} + +static const AVFilterPad perlin_outputs[] = { + { + .name = "default", + .type = AVMEDIA_TYPE_VIDEO, + .request_frame = request_frame, + .config_props = config_props, + }, +}; + +const AVFilter ff_vsrc_perlin = { + .name = "perlin", + .description = NULL_IF_CONFIG_SMALL("Generate Perlin noise"), + .priv_size = sizeof(PerlinContext), + .priv_class = &perlin_class, + .init = init, + .inputs = NULL, + FILTER_OUTPUTS(perlin_outputs), + FILTER_QUERY_FUNC(query_formats), +}; -- 2.34.1
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