mirror of
https://github.com/RetroDECK/Duckstation.git
synced 2024-11-24 14:45:41 +00:00
252 lines
9.3 KiB
HLSL
252 lines
9.3 KiB
HLSL
/**
|
|
* Deband shader by haasn
|
|
* https://github.com/haasn/gentoo-conf/blob/xor/home/nand/.mpv/shaders/deband-pre.glsl
|
|
*
|
|
* Copyright (c) 2015 Niklas Haas
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
* SOFTWARE.
|
|
*
|
|
* Modified and optimized for ReShade by JPulowski
|
|
* https://reshade.me/forum/shader-presentation/768-deband
|
|
*
|
|
* Do not distribute without giving credit to the original author(s).
|
|
*
|
|
* 1.0 - Initial release
|
|
* 1.1 - Replaced the algorithm with the one from MPV
|
|
* 1.1a - Minor optimizations
|
|
* - Removed unnecessary lines and replaced them with ReShadeFX intrinsic counterparts
|
|
* 2.0 - Replaced "grain" with CeeJay.dk's ordered dithering algorithm and enabled it by default
|
|
* - The configuration is now more simpler and straightforward
|
|
* - Some minor code changes and optimizations
|
|
* - Improved the algorithm and made it more robust by adding some of the madshi's
|
|
* improvements to flash3kyuu_deband which should cause an increase in quality. Higher
|
|
* iterations/ranges should now yield higher quality debanding without too much decrease
|
|
* in quality.
|
|
* - Changed licensing text and original source code URL
|
|
* 3.0 - Replaced the entire banding detection algorithm with modified standard deviation and
|
|
* Weber ratio analyses which give more accurate and error-free results compared to the
|
|
* previous algorithm
|
|
* - Added banding map debug view
|
|
* - Added and redefined UI categories
|
|
* - Added depth detection (credits to spiro) which should be useful when banding only
|
|
* occurs in the sky texture for example
|
|
* - Fixed a bug in random number generation which was causing artifacts on the upper left
|
|
* side of the screen
|
|
* - Dithering is now applied only when debanding a pixel as it should be which should
|
|
* reduce the overall noise in the final texture
|
|
* - Minor code optimizations
|
|
* 3.1 - Switched to chroma-based analysis from luma-based analysis which was causing artifacts
|
|
* under some scenarios
|
|
* - Changed parts of the code which was causing compatibility issues on some renderers
|
|
*/
|
|
|
|
#include "ReShadeUI.fxh"
|
|
#include "ReShade.fxh"
|
|
|
|
uniform bool enable_weber <
|
|
ui_category = "Banding analysis";
|
|
ui_label = "Weber ratio";
|
|
ui_tooltip = "Weber ratio analysis that calculates the ratio of the each local pixel's intensity to average background intensity of all the local pixels.";
|
|
ui_type = "radio";
|
|
> = true;
|
|
|
|
uniform bool enable_sdeviation <
|
|
ui_category = "Banding analysis";
|
|
ui_label = "Standard deviation";
|
|
ui_tooltip = "Modified standard deviation analysis that calculates nearby pixels' intensity deviation from the current pixel instead of the mean.";
|
|
ui_type = "radio";
|
|
> = true;
|
|
|
|
uniform bool enable_depthbuffer <
|
|
ui_category = "Banding analysis";
|
|
ui_label = "Depth detection";
|
|
ui_tooltip = "Allows depth information to be used when analysing banding, pixels will only be analysed if they are in a certain depth. (e.g. debanding only the sky)";
|
|
ui_type = "radio";
|
|
> = false;
|
|
|
|
uniform float t1 <
|
|
ui_category = "Banding analysis";
|
|
ui_label = "Standard deviation threshold";
|
|
ui_max = 0.5;
|
|
ui_min = 0.0;
|
|
ui_step = 0.001;
|
|
ui_tooltip = "Standard deviations lower than this threshold will be flagged as flat regions with potential banding.";
|
|
ui_type = "slider";
|
|
> = 0.007;
|
|
|
|
uniform float t2 <
|
|
ui_category = "Banding analysis";
|
|
ui_label = "Weber ratio threshold";
|
|
ui_max = 2.0;
|
|
ui_min = 0.0;
|
|
ui_step = 0.01;
|
|
ui_tooltip = "Weber ratios lower than this threshold will be flagged as flat regions with potential banding.";
|
|
ui_type = "slider";
|
|
> = 0.04;
|
|
|
|
uniform float banding_depth <
|
|
ui_category = "Banding analysis";
|
|
ui_label = "Banding depth";
|
|
ui_max = 1.0;
|
|
ui_min = 0.0;
|
|
ui_step = 0.001;
|
|
ui_tooltip = "Pixels under this depth threshold will not be processed and returned as they are.";
|
|
ui_type = "slider";
|
|
> = 1.0;
|
|
|
|
uniform float range <
|
|
ui_category = "Banding detection & removal";
|
|
ui_label = "Radius";
|
|
ui_max = 32.0;
|
|
ui_min = 1.0;
|
|
ui_step = 1.0;
|
|
ui_tooltip = "The radius increases linearly for each iteration. A higher radius will find more gradients, but a lower radius will smooth more aggressively.";
|
|
ui_type = "slider";
|
|
> = 24.0;
|
|
|
|
uniform int iterations <
|
|
ui_category = "Banding detection & removal";
|
|
ui_label = "Iterations";
|
|
ui_max = 4;
|
|
ui_min = 1;
|
|
ui_tooltip = "The number of debanding steps to perform per sample. Each step reduces a bit more banding, but takes time to compute.";
|
|
ui_type = "slider";
|
|
> = 1;
|
|
|
|
uniform int debug_output <
|
|
ui_category = "Debug";
|
|
ui_items = "None\0Blurred (LPF) image\0Banding map\0";
|
|
ui_label = "Debug view";
|
|
ui_tooltip = "Blurred (LPF) image: Useful when tweaking radius and iterations to make sure all banding regions are blurred enough.\nBanding map: Useful when tweaking analysis parameters, continuous green regions indicate flat (i.e. banding) regions.";
|
|
ui_type = "combo";
|
|
> = 0;
|
|
|
|
// Reshade uses C rand for random, max cannot be larger than 2^15-1
|
|
uniform int drandom < source = "random"; min = 0; max = 32767; >;
|
|
|
|
float rand(float x)
|
|
{
|
|
return frac(x / 41.0);
|
|
}
|
|
|
|
float permute(float x)
|
|
{
|
|
return ((34.0 * x + 1.0) * x) % 289.0;
|
|
}
|
|
|
|
float3 PS_Deband(float4 vpos : SV_Position, float2 texcoord : TexCoord) : SV_Target
|
|
{
|
|
float3 ori = tex2Dlod(ReShade::BackBuffer, float4(texcoord, 0.0, 0.0)).rgb;
|
|
|
|
if (enable_depthbuffer && (ReShade::GetLinearizedDepth(texcoord) < banding_depth))
|
|
return ori;
|
|
|
|
// Initialize the PRNG by hashing the position + a random uniform
|
|
float3 m = float3(texcoord + 1.0, (drandom / 32767.0) + 1.0);
|
|
float h = permute(permute(permute(m.x) + m.y) + m.z);
|
|
|
|
// Compute a random angle
|
|
float dir = rand(permute(h)) * 6.2831853;
|
|
float2 o;
|
|
sincos(dir, o.y, o.x);
|
|
|
|
// Distance calculations
|
|
float2 pt;
|
|
float dist;
|
|
|
|
for (int i = 1; i <= iterations; ++i) {
|
|
dist = rand(h) * range * i;
|
|
pt = dist * BUFFER_PIXEL_SIZE;
|
|
|
|
h = permute(h);
|
|
}
|
|
|
|
// Sample at quarter-turn intervals around the source pixel
|
|
float3 ref[4] = {
|
|
tex2Dlod(ReShade::BackBuffer, float4(mad(pt, o, texcoord), 0.0, 0.0)).rgb, // SE
|
|
tex2Dlod(ReShade::BackBuffer, float4(mad(pt, -o, texcoord), 0.0, 0.0)).rgb, // NW
|
|
tex2Dlod(ReShade::BackBuffer, float4(mad(pt, float2(-o.y, o.x), texcoord), 0.0, 0.0)).rgb, // NE
|
|
tex2Dlod(ReShade::BackBuffer, float4(mad(pt, float2( o.y, -o.x), texcoord), 0.0, 0.0)).rgb // SW
|
|
};
|
|
|
|
// Calculate weber ratio
|
|
float3 mean = (ori + ref[0] + ref[1] + ref[2] + ref[3]) * 0.2;
|
|
float3 k = abs(ori - mean);
|
|
for (int j = 0; j < 4; ++j) {
|
|
k += abs(ref[j] - mean);
|
|
}
|
|
|
|
k = k * 0.2 / mean;
|
|
|
|
// Calculate std. deviation
|
|
float3 sd = 0.0;
|
|
|
|
for (int j = 0; j < 4; ++j) {
|
|
sd += pow(ref[j] - ori, 2);
|
|
}
|
|
|
|
sd = sqrt(sd * 0.25);
|
|
|
|
// Generate final output
|
|
float3 output;
|
|
|
|
if (debug_output == 2)
|
|
output = float3(0.0, 1.0, 0.0);
|
|
else
|
|
output = (ref[0] + ref[1] + ref[2] + ref[3]) * 0.25;
|
|
|
|
// Generate a binary banding map
|
|
bool3 banding_map = true;
|
|
|
|
if (debug_output != 1) {
|
|
if (enable_weber)
|
|
banding_map = banding_map && k <= t2 * iterations;
|
|
|
|
if (enable_sdeviation)
|
|
banding_map = banding_map && sd <= t1 * iterations;
|
|
}
|
|
|
|
/*------------------------.
|
|
| :: Ordered Dithering :: |
|
|
'------------------------*/
|
|
//Calculate grid position
|
|
float grid_position = frac(dot(texcoord, (BUFFER_SCREEN_SIZE * float2(1.0 / 16.0, 10.0 / 36.0)) + 0.25));
|
|
|
|
//Calculate how big the shift should be
|
|
float dither_shift = 0.25 * (1.0 / (pow(2, BUFFER_COLOR_BIT_DEPTH) - 1.0));
|
|
|
|
//Shift the individual colors differently, thus making it even harder to see the dithering pattern
|
|
float3 dither_shift_RGB = float3(dither_shift, -dither_shift, dither_shift); //subpixel dithering
|
|
|
|
//modify shift acording to grid position.
|
|
dither_shift_RGB = lerp(2.0 * dither_shift_RGB, -2.0 * dither_shift_RGB, grid_position); //shift acording to grid position.
|
|
|
|
return banding_map ? output + dither_shift_RGB : ori;
|
|
}
|
|
|
|
technique Deband <
|
|
ui_tooltip = "Alleviates color banding by trying to approximate original color values.";
|
|
>
|
|
{
|
|
pass
|
|
{
|
|
VertexShader = PostProcessVS;
|
|
PixelShader = PS_Deband;
|
|
}
|
|
} |