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Optimal sharpening strength (according to objective metrics) - 0.5. Can be applied only to luma channel (change OUTPUT to LUMA). To use it on-demand add the following line to input.conf: n change-list glsl-shaders toggle "~~/adaptive-sharpen.glsl"
// Copyright (c) 2015-2021, bacondither
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer
// in this position and unchanged.
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
// OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
// IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
// NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Adaptive sharpen - version 2021-10-17
// Tuned for use post-resize
//!HOOK OUTPUT
//!BIND HOOKED
//!DESC adaptive-sharpen
//--------------------------------------- Settings ------------------------------------------------
#define curve_height 1.0 // Main control of sharpening strength [>0]
// 0.3 <-> 2.0 is a reasonable range of values
#define overshoot_ctrl false // Allow for higher overshoot if the current edge pixel
// is surrounded by similar edge pixels
// Defined values under this row are "optimal" DO NOT CHANGE IF YOU DO NOT KNOW WHAT YOU ARE DOING!
#define curveslope 0.5 // Sharpening curve slope, high edge values
#define L_compr_low 0.167 // Light compression, default (0.167=~6x)
#define L_compr_high 0.334 // Light compression, surrounded by edges (0.334=~3x)
#define D_compr_low 0.250 // Dark compression, default (0.250=4x)
#define D_compr_high 0.500 // Dark compression, surrounded by edges (0.500=2x)
#define scale_lim 0.1 // Abs max change before compression [>0.01]
#define scale_cs 0.056 // Compression slope above scale_lim
#define pm_p 1.0 // Power mean p-value [>0-1.0]
//-------------------------------------------------------------------------------------------------
#define max4(a,b,c,d) ( max(max(a, b), max(c, d)) )
// Soft if, fast linear approx
#define soft_if(a,b,c) ( sat((a + b + c + 0.056/2.5)/(maxedge + 0.03/2.5) - 0.85) )
// Soft limit, modified tanh approx
#define soft_lim(v,s) ( sat(abs(v/s)*(27.0 + pow(v/s, 2.0))/(27.0 + 9.0*pow(v/s, 2.0)))*s )
// Weighted power mean
#define wpmean(a,b,w) ( pow(w*pow(abs(a), pm_p) + abs(1.0-w)*pow(abs(b), pm_p), (1.0/pm_p)) )
// Get destination pixel values
#define get(x,y) ( HOOKED_texOff(vec2(x, y)).rgb )
#define sat(x) ( clamp(x, 0.0, 1.0) )
#define dxdy(val) ( length(fwidth(val)) ) // =~1/2.5 hq edge without c_comp
#ifdef LUMA_tex
#define CtL(RGB) RGB.x
#else
#define CtL(RGB) ( sqrt(dot(sat(RGB)*sat(RGB), vec3(0.2126, 0.7152, 0.0722))) )
#endif
#define b_diff(pix) ( (blur-luma[pix])*(blur-luma[pix]) )
vec4 hook() {
// [ c22 ]
// [ c24, c9, c23 ]
// [ c21, c1, c2, c3, c18 ]
// [ c19, c10, c4, c0, c5, c11, c16 ]
// [ c20, c6, c7, c8, c17 ]
// [ c15, c12, c14 ]
// [ c13 ]
vec3 c[25] = vec3[](get( 0, 0), get(-1,-1), get( 0,-1), get( 1,-1), get(-1, 0),
get( 1, 0), get(-1, 1), get( 0, 1), get( 1, 1), get( 0,-2),
get(-2, 0), get( 2, 0), get( 0, 2), get( 0, 3), get( 1, 2),
get(-1, 2), get( 3, 0), get( 2, 1), get( 2,-1), get(-3, 0),
get(-2, 1), get(-2,-1), get( 0,-3), get( 1,-2), get(-1,-2));
float e[13] = float[](dxdy(c[0]), dxdy(c[1]), dxdy(c[2]), dxdy(c[3]), dxdy(c[4]),
dxdy(c[5]), dxdy(c[6]), dxdy(c[7]), dxdy(c[8]), dxdy(c[9]),
dxdy(c[10]), dxdy(c[11]), dxdy(c[12]));
// RGB to luma
float luma[25] = float[](CtL(c[0]), CtL(c[1]), CtL(c[2]), CtL(c[3]), CtL(c[4]), CtL(c[5]), CtL(c[6]),
CtL(c[7]), CtL(c[8]), CtL(c[9]), CtL(c[10]), CtL(c[11]), CtL(c[12]),
CtL(c[13]), CtL(c[14]), CtL(c[15]), CtL(c[16]), CtL(c[17]), CtL(c[18]),
CtL(c[19]), CtL(c[20]), CtL(c[21]), CtL(c[22]), CtL(c[23]), CtL(c[24]));
float c0_Y = luma[0];
// Blur, gauss 3x3
float blur = (2.0 * (luma[2]+luma[4]+luma[5]+luma[7]) + (luma[1]+luma[3]+luma[6]+luma[8]) + 4.0 * luma[0]) / 16.0;
// Contrast compression, center = 0.5
float c_comp = sat(0.266666681f + 0.9*exp2(blur * blur * -7.4));
// Edge detection
// Relative matrix weights
// [ 1 ]
// [ 4, 5, 4 ]
// [ 1, 5, 6, 5, 1 ]
// [ 4, 5, 4 ]
// [ 1 ]
float edge = ( 1.38*b_diff(0)
+ 1.15*(b_diff(2) + b_diff(4) + b_diff(5) + b_diff(7))
+ 0.92*(b_diff(1) + b_diff(3) + b_diff(6) + b_diff(8))
+ 0.23*(b_diff(9) + b_diff(10) + b_diff(11) + b_diff(12)) ) * c_comp;
vec2 cs = vec2(L_compr_low, D_compr_low);
if (overshoot_ctrl) {
float maxedge = max4( max4(e[1],e[2],e[3],e[4]), max4(e[5],e[6],e[7],e[8]),
max4(e[9],e[10],e[11],e[12]), e[0] );
// [ x ]
// [ z, x, w ]
// [ z, z, x, w, w ]
// [ y, y, y, 0, y, y, y ]
// [ w, w, x, z, z ]
// [ w, x, z ]
// [ x ]
float sbe = soft_if(e[2],e[9], dxdy(c[22]))*soft_if(e[7],e[12],dxdy(c[13])) // x dir
+ soft_if(e[4],e[10],dxdy(c[19]))*soft_if(e[5],e[11],dxdy(c[16])) // y dir
+ soft_if(e[1],dxdy(c[24]),dxdy(c[21]))*soft_if(e[8],dxdy(c[14]),dxdy(c[17])) // z dir
+ soft_if(e[3],dxdy(c[23]),dxdy(c[18]))*soft_if(e[6],dxdy(c[20]),dxdy(c[15])); // w dir
cs = mix(cs, vec2(L_compr_high, D_compr_high), sat(2.4002*sbe - 2.282));
}
// Precalculated default squared kernel weights
const vec3 w1 = vec3(0.5, 1.0, 1.41421356237); // 0.25, 1.0, 2.0
const vec3 w2 = vec3(0.86602540378, 1.0, 0.54772255751); // 0.75, 1.0, 0.3
// Transition to a concave kernel if the center edge val is above thr
vec3 dW = pow(mix( w1, w2, sat(2.4*edge - 0.82)), vec3(2.0));
// Use lower weights for pixels in a more active area relative to center pixel area
// This results in narrower and less visible overshoots around sharp edges
float modif_e0 = 3.0 * e[0] + 0.02/2.5;
float weights[12] = float[](( min(modif_e0/e[1], dW.y) ),
( dW.x ),
( min(modif_e0/e[3], dW.y) ),
( dW.x ),
( dW.x ),
( min(modif_e0/e[6], dW.y) ),
( dW.x ),
( min(modif_e0/e[8], dW.y) ),
( min(modif_e0/e[9], dW.z) ),
( min(modif_e0/e[10], dW.z) ),
( min(modif_e0/e[11], dW.z) ),
( min(modif_e0/e[12], dW.z) ));
weights[0] = (max(max((weights[8] + weights[9])/4.0, weights[0]), 0.25) + weights[0])/2.0;
weights[2] = (max(max((weights[8] + weights[10])/4.0, weights[2]), 0.25) + weights[2])/2.0;
weights[5] = (max(max((weights[9] + weights[11])/4.0, weights[5]), 0.25) + weights[5])/2.0;
weights[7] = (max(max((weights[10] + weights[11])/4.0, weights[7]), 0.25) + weights[7])/2.0;
// Calculate the negative part of the laplace kernel and the low threshold weight
float lowthrsum = 0.0;
float weightsum = 0.0;
float neg_laplace = 0.0;
for (int pix = 0; pix < 12; ++pix)
{
float lowthr = sat((20.*4.5*c_comp*e[pix + 1] - 0.221));
neg_laplace += luma[pix+1] * luma[pix+1] * weights[pix] * lowthr;
weightsum += weights[pix] * lowthr;
lowthrsum += lowthr / 12.0;
}
neg_laplace = sqrt(neg_laplace / weightsum);
// Compute sharpening magnitude function
float sharpen_val = curve_height/(curve_height*curveslope*edge + 0.625);
// Calculate sharpening diff and scale
float sharpdiff = (c0_Y - neg_laplace)*(lowthrsum*sharpen_val + 0.01);
// Calculate local near min & max, partial sort
float temp;
for (int i1 = 0; i1 < 24; i1 += 2)
{
temp = luma[i1];
luma[i1] = min(luma[i1], luma[i1+1]);
luma[i1+1] = max(temp, luma[i1+1]);
}
for (int i2 = 24; i2 > 0; i2 -= 2)
{
temp = luma[0];
luma[0] = min(luma[0], luma[i2]);
luma[i2] = max(temp, luma[i2]);
temp = luma[24];
luma[24] = max(luma[24], luma[i2-1]);
luma[i2-1] = min(temp, luma[i2-1]);
}
float min_dist = min(abs(luma[24] - c0_Y), abs(c0_Y - luma[0]));
min_dist = min(min_dist, scale_lim*(1.0 - scale_cs) + min_dist*scale_cs);
// Soft limited anti-ringing with tanh, wpmean to control compression slope
sharpdiff = wpmean(max(sharpdiff, 0.0), soft_lim( max(sharpdiff, 0.0), min_dist ), cs.x )
- wpmean(min(sharpdiff, 0.0), soft_lim( min(sharpdiff, 0.0), min_dist ), cs.y );
float sharpdiff_lim = sat(c0_Y + sharpdiff) - c0_Y;
/*float satmul = (c0_Y + max(sharpdiff_lim*0.9, sharpdiff_lim)*1.03 + 0.03)/(c0_Y + 0.03);
vec3 res = c0_Y + sharpdiff_lim + (c[0] - c0_Y)*satmul;
*/
return vec4(sharpdiff_lim + c[0], HOOKED_texOff(0).a);
}
@AziRizvi
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One question please. What line do I need to edit in this to control the intensity of this shader? I like it but I'd like the intensity to be a little less.

curve_height in https://gist.github.com/igv/8a77e4eb8276753b54bb94c1c50c317e#file-adaptive-sharpen-glsl-L34

Thanks a bunch, I feel dumb, wish I had actually taken a look inside the shader file because it's clearly mentioned in there.

@deus0ww
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deus0ww commented Dec 6, 2023

Could you use gather? In my test using a 4K video on an M1 Mac mini, both luma and rgb are about 25-30% faster.

#ifdef HOOKED_gather
    vec2 p = (HOOKED_pos * HOOKED_size - vec2(0.5)) * HOOKED_pt;
    ivec2 gatherOffsets[8] = {{ 1, 1}, { 0, 0}, { 3, 1}, { 1, 3}, {-1, 2}, {-2, 0}, { 0,-2}, { 2,-1}};
    vec4 g[3][8];
    for (int i = 0; i < 8; i++) {
        g[0][i] = HOOKED_mul * textureGatherOffset(HOOKED_raw, p, gatherOffsets[i], 0);
#ifndef LUMA_tex
        g[1][i] = HOOKED_mul * textureGatherOffset(HOOKED_raw, p, gatherOffsets[i], 1);
        g[2][i] = HOOKED_mul * textureGatherOffset(HOOKED_raw, p, gatherOffsets[i], 2);
#endif
    }
    vec3 c[25] = {{g[0][0].w, g[1][0].w, g[2][0].w}, {g[0][1].w, g[1][1].w, g[2][1].w}, {g[0][1].z, g[1][1].z, g[2][1].z}, {g[0][7].x, g[1][7].x, g[2][7].x}, {g[0][1].x, g[1][1].x, g[2][1].x},
                  {g[0][0].z, g[1][0].z, g[2][0].z}, {g[0][4].z, g[1][4].z, g[2][4].z}, {g[0][0].x, g[1][0].x, g[2][0].x}, {g[0][0].y, g[1][0].y, g[2][0].y}, {g[0][6].y, g[1][6].y, g[2][6].y},
                  {g[0][5].y, g[1][5].y, g[2][5].y}, {g[0][2].w, g[1][2].w, g[2][2].w}, {g[0][3].w, g[1][3].w, g[2][3].w}, {g[0][3].x, g[1][3].x, g[2][3].x}, {g[0][3].z, g[1][3].z, g[2][3].z},
                  {g[0][4].y, g[1][4].y, g[2][4].y}, {g[0][2].z, g[1][2].z, g[2][2].z}, {g[0][2].x, g[1][2].x, g[2][2].x}, {g[0][7].y, g[1][7].y, g[2][7].y}, {g[0][5].x, g[1][5].x, g[2][5].x},
                  {g[0][4].w, g[1][4].w, g[2][4].w}, {g[0][5].z, g[1][5].z, g[2][5].z}, {g[0][6].z, g[1][6].z, g[2][6].z}, {g[0][7].w, g[1][7].w, g[2][7].w}, {g[0][6].x, g[1][6].x, g[2][6].x}};
#else
    vec3 c[25] = vec3[](get( 0, 0), get(-1,-1), get( 0,-1), get( 1,-1), get(-1, 0),
                        get( 1, 0), get(-1, 1), get( 0, 1), get( 1, 1), get( 0,-2),
                        get(-2, 0), get( 2, 0), get( 0, 2), get( 0, 3), get( 1, 2),
                        get(-1, 2), get( 3, 0), get( 2, 1), get( 2,-1), get(-3, 0),
                        get(-2, 1), get(-2,-1), get( 0,-3), get( 1,-2), get(-1,-2));
#endif

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