lavfi: add Perlin noise generator
This commit is contained in:
Stefano Sabatini
parent
c9151ea507
commit
3764b8ecdb
@ -14,6 +14,7 @@ version <next>:
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- xHE-AAC decoder
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- xHE-AAC decoder
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- removed DEC Alpha DSP and support code
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- removed DEC Alpha DSP and support code
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- VVC encoding support via libvvenc
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- VVC encoding support via libvvenc
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- perlin video source
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version 7.0:
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version 7.0:
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100
doc/filters.texi
100
doc/filters.texi
@ -17290,6 +17290,9 @@ The command accepts the same syntax of the corresponding option.
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If the specified expression is not valid, it is kept at its current
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If the specified expression is not valid, it is kept at its current
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value.
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value.
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@anchor{lutrgb}
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@anchor{lutyuv}
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@anchor{lut}
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@section lut, lutrgb, lutyuv
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@section lut, lutrgb, lutyuv
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Compute a look-up table for binding each pixel component input value
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Compute a look-up table for binding each pixel component input value
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@ -29281,6 +29284,103 @@ ffplay -f lavfi life=s=300x200:mold=10:r=60:ratio=0.1:death_color=#C83232:life_c
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@end example
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@end example
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@end itemize
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@end itemize
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@section perlin
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Generate Perlin noise.
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Perlin noise is a kind of noise with local continuity in space. This
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can be used to generate patterns with continuity in space and time,
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e.g. to simulate smoke, fluids, or terrain.
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In case more than one octave is specified through the @option{octaves}
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option, Perlin noise is generated as a sum of components, each one
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with doubled frequency. In this case the @option{persistence} option
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specify the ratio of the amplitude with respect to the previous
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component. More octave components enable to specify more high
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frequency details in the generated noise (e.g. small size variations
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due to boulders in a generated terrain).
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@subsection Options
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@table @option
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@item size, s
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Specify the size (width and height) of the buffered video frames. For the
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syntax of this option, check the
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@ref{video size syntax,,"Video size" section in the ffmpeg-utils manual,ffmpeg-utils}.
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@item rate, r
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Specify the frame rate expected for the video stream, expressed as a
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number of frames per second.
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@item octaves
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Specify the total number of components making up the noise, each one
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with doubled frequency.
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@item persistence
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Set the ratio used to compute the amplitude of the next octave
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component with respect to the previous component amplitude.
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@item xscale
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@item yscale
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Define a scale factor used to multiple the x, y coordinates. This can
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be useful to define an effect with a pattern stretched along the x or
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y axis.
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@item tscale
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Define a scale factor used to multiple the time coordinate. This can
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be useful to change the time variation speed.
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@item random_mode
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Set random mode used to compute initial pattern.
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Supported values are:
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@table @option
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@item random
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Compute and use random seed.
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@item ken
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Use the predefined initial pattern defined by Ken Perlin in the
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original article, can be useful to compare the output with other
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sources.
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@item seed
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Use the value specified by @option{random_seed} option.
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@end table
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@item random_seed, seed
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When @option{random_mode} is set to @var{random_seed}, use this value
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to compute the initial pattern.
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@end table
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@subsection Examples
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@itemize
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@item
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Generate single component:
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@example
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perlin
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@end example
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@item
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Use Perlin noise with 7 components, each one with a halved contribution
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to total amplitude:
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@example
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perlin=octaves=7:persistence=0.5
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@end example
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@item
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Chain Perlin noise with the @ref{lutyuv} to generate a black&white
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effect:
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@example
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perlin=octaves=3:tscale=0.3,lutyuv=y='if(lt(val\,128)\,255\,0)'
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@end example
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@item
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Stretch noise along the y axis, and convert gray level to red-only
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signal:
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@example
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perlin=octaves=7:tscale=0.4:yscale=0.3,lutrgb=r=val:b=0:g=0
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@end example
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@end itemize
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@section qrencodesrc
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@section qrencodesrc
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Generate a QR code using the libqrencode library (see
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Generate a QR code using the libqrencode library (see
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@ -603,6 +603,7 @@ OBJS-$(CONFIG_NULLSRC_FILTER) += vsrc_testsrc.o
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OBJS-$(CONFIG_OPENCLSRC_FILTER) += vf_program_opencl.o opencl.o
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OBJS-$(CONFIG_OPENCLSRC_FILTER) += vf_program_opencl.o opencl.o
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OBJS-$(CONFIG_PAL75BARS_FILTER) += vsrc_testsrc.o
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OBJS-$(CONFIG_PAL75BARS_FILTER) += vsrc_testsrc.o
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OBJS-$(CONFIG_PAL100BARS_FILTER) += vsrc_testsrc.o
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OBJS-$(CONFIG_PAL100BARS_FILTER) += vsrc_testsrc.o
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OBJS-$(CONFIG_PERLIN_FILTER) += vsrc_perlin.o perlin.o
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OBJS-$(CONFIG_QRENCODE_FILTER) += qrencode.o textutils.o
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OBJS-$(CONFIG_QRENCODE_FILTER) += qrencode.o textutils.o
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OBJS-$(CONFIG_QRENCODESRC_FILTER) += qrencode.o textutils.o
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OBJS-$(CONFIG_QRENCODESRC_FILTER) += qrencode.o textutils.o
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OBJS-$(CONFIG_RGBTESTSRC_FILTER) += vsrc_testsrc.o
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OBJS-$(CONFIG_RGBTESTSRC_FILTER) += vsrc_testsrc.o
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@ -569,6 +569,7 @@ extern const AVFilter ff_vsrc_openclsrc;
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extern const AVFilter ff_vsrc_qrencodesrc;
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extern const AVFilter ff_vsrc_qrencodesrc;
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extern const AVFilter ff_vsrc_pal75bars;
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extern const AVFilter ff_vsrc_pal75bars;
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extern const AVFilter ff_vsrc_pal100bars;
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extern const AVFilter ff_vsrc_pal100bars;
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extern const AVFilter ff_vsrc_perlin;
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extern const AVFilter ff_vsrc_rgbtestsrc;
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extern const AVFilter ff_vsrc_rgbtestsrc;
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extern const AVFilter ff_vsrc_sierpinski;
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extern const AVFilter ff_vsrc_sierpinski;
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extern const AVFilter ff_vsrc_smptebars;
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extern const AVFilter ff_vsrc_smptebars;
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224
libavfilter/perlin.c
Normal file
224
libavfilter/perlin.c
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@ -0,0 +1,224 @@
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/*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with FFmpeg; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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/**
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* @file
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* Perlin Noise generator, based on code from:
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* https://adrianb.io/2014/08/09/perlinnoise.html
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*
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* Original article from Ken Perlin:
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* http://mrl.nyu.edu/~perlin/paper445.pdf
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*/
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#include <math.h>
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#include "libavutil/lfg.h"
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#include "libavutil/random_seed.h"
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#include "perlin.h"
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static inline int inc(int num, int period)
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{
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num++;
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if (period > 0)
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num %= period;
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return num;
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}
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static inline double grad(int hash, double x, double y, double z)
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{
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// Take the hashed value and take the first 4 bits of it (15 == 0b1111)
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int h = hash & 15;
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// If the most significant bit (MSB) of the hash is 0 then set u = x. Otherwise y.
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double u = h < 8 /* 0b1000 */ ? x : y;
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double v;
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// In Ken Perlin's original implementation this was another
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// conditional operator (?:), then expanded for readability.
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if (h < 4 /* 0b0100 */)
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// If the first and second significant bits are 0 set v = y
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v = y;
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// If the first and second significant bits are 1 set v = x
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else if (h == 12 /* 0b1100 */ || h == 14 /* 0b1110 */)
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v = x;
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else
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// If the first and second significant bits are not equal (0/1, 1/0) set v = z
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v = z;
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// Use the last 2 bits to decide if u and v are positive or negative. Then return their addition.
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return ((h&1) == 0 ? u : -u)+((h&2) == 0 ? v : -v);
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}
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static inline double fade(double t)
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{
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// Fade function as defined by Ken Perlin. This eases coordinate values
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// so that they will "ease" towards integral values. This ends up smoothing
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// the final output.
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// use Horner method to compute: 6t^5 - 15t^4 + 10t^3
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return t * t * t * (t * (t * 6 - 15) + 10);
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}
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static double lerp(double a, double b, double x)
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{
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return a + x * (b - a);
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}
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// Hash lookup table as defined by Ken Perlin. This is a randomly
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// arranged array of all numbers from 0-255 inclusive.
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static uint8_t ken_permutations[] = {
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151, 160, 137, 91, 90, 15, 131, 13, 201, 95, 96, 53, 194, 233, 7, 225,
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140, 36, 103, 30, 69, 142, 8, 99, 37, 240, 21, 10, 23, 190, 6, 148,
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247, 120, 234, 75, 0, 26, 197, 62, 94, 252, 219, 203, 117, 35, 11, 32,
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57, 177, 33, 88, 237, 149, 56, 87, 174, 20, 125, 136, 171, 168, 68, 175,
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74, 165, 71, 134, 139, 48, 27, 166, 77, 146, 158, 231, 83, 111, 229, 122,
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60, 211, 133, 230, 220, 105, 92, 41, 55, 46, 245, 40, 244, 102, 143, 54,
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65, 25, 63, 161, 1, 216, 80, 73, 209, 76, 132, 187, 208, 89, 18, 169,
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200, 196, 135, 130, 116, 188, 159, 86, 164, 100, 109, 198, 173, 186, 3, 64,
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52, 217, 226, 250, 124, 123, 5, 202, 38, 147, 118, 126, 255, 82, 85, 212,
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207, 206, 59, 227, 47, 16, 58, 17, 182, 189, 28, 42, 223, 183, 170, 213,
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119, 248, 152, 2, 44, 154, 163, 70, 221, 153, 101, 155, 167, 43, 172, 9,
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129, 22, 39, 253, 19, 98, 108, 110, 79, 113, 224, 232, 178, 185, 112, 104,
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218, 246, 97, 228, 251, 34, 242, 193, 238, 210, 144, 12, 191, 179, 162, 241,
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81, 51, 145, 235, 249, 14, 239, 107, 49, 192, 214, 31, 181, 199, 106, 157,
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184, 84, 204, 176, 115, 121, 50, 45, 127, 4, 150, 254, 138, 236, 205, 93,
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222, 114, 67, 29, 24, 72, 243, 141, 128, 195, 78, 66, 215, 61, 156, 180
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};
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int ff_perlin_init(FFPerlin *perlin, double period, int octaves, double persistence,
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enum FFPerlinRandomMode random_mode, unsigned int random_seed)
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{
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int i;
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perlin->period = period;
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perlin->octaves = octaves;
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perlin->persistence = persistence;
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perlin->random_mode = random_mode;
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perlin->random_seed = random_seed;
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if (perlin->random_mode == FF_PERLIN_RANDOM_MODE_KEN) {
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for (i = 0; i < 512; i++) {
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perlin->permutations[i] = ken_permutations[i % 256];
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}
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} else {
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AVLFG lfg;
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uint8_t random_permutations[256];
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if (perlin->random_mode == FF_PERLIN_RANDOM_MODE_RANDOM)
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perlin->random_seed = av_get_random_seed();
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av_lfg_init(&lfg, perlin->random_seed);
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for (i = 0; i < 256; i++) {
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random_permutations[i] = i;
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}
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for (i = 0; i < 256; i++) {
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unsigned int random_idx = av_lfg_get(&lfg) % (256-i);
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uint8_t random_val = random_permutations[random_idx];
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random_permutations[random_idx] = random_permutations[256-i];
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perlin->permutations[i] = perlin->permutations[i+256] = random_val;
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}
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}
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return 0;
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}
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static double perlin_get(FFPerlin *perlin, double x, double y, double z)
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{
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int xi, yi, zi;
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double xf, yf, zf;
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double u, v, w;
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const uint8_t *p = perlin->permutations;
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double period = perlin->period;
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int aaa, aba, aab, abb, baa, bba, bab, bbb;
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double x1, x2, y1, y2;
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if (perlin->period > 0) {
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// If we have any period on, change the coordinates to their "local" repetitions
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x = fmod(x, perlin->period);
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y = fmod(y, perlin->period);
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z = fmod(z, perlin->period);
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}
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// Calculate the "unit cube" that the point asked will be located in
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// The left bound is ( |_x_|,|_y_|,|_z_| ) and the right bound is that
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// plus 1. Next we calculate the location (from 0.0 to 1.0) in that cube.
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xi = (int)x & 255;
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yi = (int)y & 255;
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zi = (int)z & 255;
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xf = x - (int)x;
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yf = y - (int)y;
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zf = z - (int)z;
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// We also fade the location to smooth the result.
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u = fade(xf);
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v = fade(yf);
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w = fade(zf);
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aaa = p[p[p[ xi ] + yi ] + zi ];
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aba = p[p[p[ xi ] + inc(yi, period)] + zi ];
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aab = p[p[p[ xi ] + yi ] + inc(zi, period)];
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abb = p[p[p[ xi ] + inc(yi, period)] + inc(zi, period)];
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baa = p[p[p[inc(xi, period)] + yi ] + zi ];
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bba = p[p[p[inc(xi, period)] + inc(yi, period)] + zi ];
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bab = p[p[p[inc(xi, period)] + yi ] + inc(zi, period)];
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bbb = p[p[p[inc(xi, period)] + inc(yi, period)] + inc(zi, period)];
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// The gradient function calculates the dot product between a pseudorandom
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// gradient vector and the vector from the input coordinate to the 8
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// surrounding points in its unit cube.
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// This is all then lerped together as a sort of weighted average based on the faded (u,v,w)
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// values we made earlier.
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x1 = lerp(grad(aaa, xf , yf , zf),
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grad(baa, xf-1, yf , zf),
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u);
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x2 = lerp(grad(aba, xf , yf-1, zf),
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grad(bba, xf-1, yf-1, zf),
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u);
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y1 = lerp(x1, x2, v);
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||||||
|
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;
|
||||||
|
}
|
||||||
|
|
||||||
101
libavfilter/perlin.h
Normal file
101
libavfilter/perlin.h
Normal file
@ -0,0 +1,101 @@
|
|||||||
|
/*
|
||||||
|
* 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
|
||||||
|
};
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Perlin generator context. This needs to be initialized with the
|
||||||
|
* parameters used to generate the Perlin noise.
|
||||||
|
*/
|
||||||
|
typedef struct FFPerlin {
|
||||||
|
/**
|
||||||
|
* spatial repeat period, if negative it is ignored
|
||||||
|
*/
|
||||||
|
double period;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* total number of components making up the noise, each one with
|
||||||
|
* doubled frequency
|
||||||
|
*/
|
||||||
|
int octaves;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* ratio used to compute the amplitude of the next octave
|
||||||
|
* component with respect to the previous component
|
||||||
|
*/
|
||||||
|
double persistence;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* permutations array used to compute the Perlin noise hash
|
||||||
|
*/
|
||||||
|
uint8_t permutations[512];
|
||||||
|
|
||||||
|
/**
|
||||||
|
* define how to compute the permutations array
|
||||||
|
*/
|
||||||
|
enum FFPerlinRandomMode random_mode;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* when random_mode is set FF_PERLIN_RANDOM_MODE_RANDOM, set random
|
||||||
|
* seed used to compute the permutations array
|
||||||
|
*/
|
||||||
|
unsigned int random_seed;
|
||||||
|
} FFPerlin;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Initialize the Perlin noise generator with parameters.
|
||||||
|
*
|
||||||
|
* @param perlin Perlin noise generator context
|
||||||
|
* @param period spatial repeat period, if negative it is ignored
|
||||||
|
* @param octaves total number of components making up the noise, each one with doubled frequency
|
||||||
|
* @param persistence define ratio used to compute the amplitude of the next octave
|
||||||
|
* component with respect to the previous component
|
||||||
|
* @param random_mode define how to compute the permutations array
|
||||||
|
* @param random_seed when random_mode is set to FF_PERLIN_RANDOM_MODE_RANDOM, set random
|
||||||
|
* seed used to compute the permutations array
|
||||||
|
* @return a negative AVERROR code in case of error, a non negative value otherwise
|
||||||
|
*/
|
||||||
|
int ff_perlin_init(FFPerlin *perlin, double period, int octaves, double persistence,
|
||||||
|
enum FFPerlinRandomMode random_mode, unsigned int random_seed);
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Compute Perlin noise given the x, y, z coordinates.
|
||||||
|
*
|
||||||
|
* @param perlin Perlin noise generator context
|
||||||
|
* @return normalized value for the perlin noise, in the range [0, 1]
|
||||||
|
*/
|
||||||
|
double ff_perlin_get(FFPerlin *perlin, double x, double y, double z);
|
||||||
|
|
||||||
|
#endif /* AVFILTER_PERLIN_H */
|
||||||
169
libavfilter/vsrc_perlin.c
Normal file
169
libavfilter/vsrc_perlin.c
Normal file
@ -0,0 +1,169 @@
|
|||||||
|
/*
|
||||||
|
* 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 used to compute initial pattern", 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", "compute and use random seed", 0, AV_OPT_TYPE_CONST, {.i64=FF_PERLIN_RANDOM_MODE_RANDOM}, 0, 0, FLAGS, .unit = "random_mode" },
|
||||||
|
{ "ken", "use the predefined initial pattern defined by Ken Perlin in the original article", 0, AV_OPT_TYPE_CONST, {.i64=FF_PERLIN_RANDOM_MODE_KEN}, 0, 0, FLAGS, .unit = "random_mode" },
|
||||||
|
{ "seed", "use the value specified by random_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 pattern", OFFSET(random_seed), AV_OPT_TYPE_UINT, {.i64=0}, 0, UINT_MAX, FLAGS },
|
||||||
|
{ "seed", "set the seed for filling the initial pattern", 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, -1, 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_DEBUG, "x:%f y:%f t:%f => %f\n", x, y, t, 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),
|
||||||
|
};
|
||||||
Loading…
x
Reference in New Issue
Block a user