mirror of
https://github.com/italicsjenga/slang-shaders.git
synced 2024-11-25 08:51:32 +11:00
add ntsc-xot shader and preset
This commit is contained in:
hunterk
parent
de73a1a98e
commit
a9455fec40
9
ntsc/ntsc-xot.slangp
Normal file
9
ntsc/ntsc-xot.slangp
Normal file
|
|
@ -0,0 +1,9 @@
|
|||
shaders = 2
|
||||
|
||||
shader0 = ../stock.slang
|
||||
scale_type_x0 = absolute
|
||||
scale_x0 = "640.0"
|
||||
|
||||
shader1 = shaders/ntsc-xot.slang
|
||||
scale1 = 1.0
|
||||
scale_type1 = source
|
||||
228
ntsc/shaders/ntsc-xot.slang
Normal file
228
ntsc/shaders/ntsc-xot.slang
Normal file
|
|
@ -0,0 +1,228 @@
|
|||
#version 450
|
||||
|
||||
// NTSC Decoder
|
||||
//
|
||||
// Decodes composite video signal generated in Buffer A.
|
||||
// Move mouse to display the original signal.
|
||||
//
|
||||
// This is an intensive shader with a lot of sampling and
|
||||
// iterated filtering. Reduce filter width N to trade quality
|
||||
// for performance. N should be an integer multiple of four,
|
||||
// plus one (4n+1). Apologies to owners of melted phones.
|
||||
//
|
||||
// hunterk made the shader work in RGB instead of just a single
|
||||
// channel, though there's probably better ways to do it than
|
||||
// just tripling all of the operations. Improvements are welcome!
|
||||
//
|
||||
// copyright (c) 2017, John Leffingwell
|
||||
// license CC BY-SA Attribution-ShareAlike
|
||||
// adapted for RetroAch by hunterk from this shadertoy:
|
||||
// https://www.shadertoy.com/view/Mdffz7
|
||||
|
||||
layout(push_constant) uniform Push
|
||||
{
|
||||
vec4 SourceSize;
|
||||
vec4 OriginalSize;
|
||||
vec4 OutputSize;
|
||||
uint FrameCount;
|
||||
} params;
|
||||
|
||||
layout(std140, set = 0, binding = 0) uniform UBO
|
||||
{
|
||||
mat4 MVP;
|
||||
} global;
|
||||
|
||||
#pragma stage vertex
|
||||
layout(location = 0) in vec4 Position;
|
||||
layout(location = 1) in vec2 TexCoord;
|
||||
layout(location = 0) out vec2 vTexCoord;
|
||||
|
||||
void main()
|
||||
{
|
||||
gl_Position = global.MVP * Position;
|
||||
vTexCoord = TexCoord;
|
||||
}
|
||||
|
||||
#pragma stage fragment
|
||||
layout(location = 0) in vec2 vTexCoord;
|
||||
layout(location = 0) out vec4 FragColor;
|
||||
layout(set = 0, binding = 2) uniform sampler2D Source;
|
||||
|
||||
#define PI 3.14159265358979323846
|
||||
#define TAU 6.28318530717958647693
|
||||
|
||||
// TV adjustments
|
||||
const float SAT = 1.0; // Saturation / "Color" (normally 1.0)
|
||||
const float HUE = 1.0; // Hue / "Tint" (normally 0.0)
|
||||
const float BRI = 1.0; // Brightness (normally 1.0)
|
||||
|
||||
// Filter parameters
|
||||
const int N = 21; // Filter Width (4n+1)
|
||||
const float FC = 0.125; // Frequency Cutoff
|
||||
|
||||
|
||||
const mat3 YIQ2RGB = mat3(1.000, 1.000, 1.000,
|
||||
0.956,-0.272,-1.106,
|
||||
0.621,-0.647, 1.703);
|
||||
|
||||
vec3 adjust(vec3 YIQ, float H, float S, float B) {
|
||||
mat3 M = mat3( B, 0.0, 0.0,
|
||||
0.0, S*cos(H), -sin(H),
|
||||
0.0, sin(H), S*cos(H) );
|
||||
return M * YIQ;
|
||||
}
|
||||
|
||||
float sinc(float n) {
|
||||
if (n == 0.0) return 1.0;
|
||||
return sin(PI*n) / (PI*n);
|
||||
}
|
||||
|
||||
float window_blackman(float n, float N) {
|
||||
return 0.42 - 0.5 * cos((2.0*PI*n)/(N-1.0)) + 0.08 * cos((4.0*PI*n)/(N-1.0));
|
||||
}
|
||||
|
||||
float pulse(float a, float b, float x) {
|
||||
return step(a, x) * step(x, b);
|
||||
}
|
||||
|
||||
void main()
|
||||
{
|
||||
vec2 size = params.SourceSize.xy;
|
||||
vec2 uv = vTexCoord.xy;
|
||||
|
||||
// Compute sampling offsets and weights
|
||||
float sumR = 0.0;
|
||||
float sumG = 0.0;
|
||||
float sumB = 0.0;
|
||||
vec4 offsetR[N];
|
||||
vec4 offsetG[N];
|
||||
vec4 offsetB[N];
|
||||
|
||||
// R
|
||||
for (int i=0; i<N; i++) {
|
||||
float jR = float(i) - (float(N-1)/2.0);
|
||||
float kR = sinc( 2.0 * FC * jR) * window_blackman(float(i),float(N));
|
||||
offsetR[i] = vec4(jR/size.x, 0.0, kR, -kR);
|
||||
sumR += kR;
|
||||
}
|
||||
|
||||
// Low-pass filter input signal
|
||||
float tapR[N];
|
||||
for (int i=0; i<N; i++) {
|
||||
offsetR[i].zw /= sumR;
|
||||
tapR[i] = pulse(0.0, 1.0, uv.x + offsetR[i].x) * texture(Source, uv + offsetR[i].xy).r;
|
||||
}
|
||||
offsetR[(N-1)/2].w += 1.0;
|
||||
|
||||
// Extract luma signal
|
||||
float lumaR = 0.0;
|
||||
for (int i=0; i<N; i++) {
|
||||
lumaR += tapR[i] * offsetR[i].z;
|
||||
}
|
||||
|
||||
// Extract chroma signal
|
||||
float chromaR[N];
|
||||
for (int j=0; j<N; j++) {
|
||||
chromaR[j] = 0.0;
|
||||
for (int i=0; i<N; i++) {
|
||||
chromaR[j] += tapR[i+j-(N-1)/2] * offsetR[i].w;
|
||||
}
|
||||
}
|
||||
|
||||
// G
|
||||
for (int i=0; i<N; i++) {
|
||||
float jG = float(i) - (float(N-1)/2.0);
|
||||
float kG = sinc( 2.0 * FC * jG) * window_blackman(float(i),float(N));
|
||||
offsetG[i] = vec4(jG/size.x, 0.0, kG, -kG);
|
||||
sumG += kG;
|
||||
}
|
||||
|
||||
// Low-pass filter input signal
|
||||
float tapG[N];
|
||||
for (int i=0; i<N; i++) {
|
||||
offsetG[i].zw /= sumG;
|
||||
tapG[i] = pulse(0.0, 1.0, uv.x + offsetG[i].x) * texture(Source, uv + offsetG[i].xy).g;
|
||||
}
|
||||
offsetG[(N-1)/2].w += 1.0;
|
||||
|
||||
// Extract luma signal
|
||||
float lumaG = 0.0;
|
||||
for (int i=0; i<N; i++) {
|
||||
lumaG += tapG[i] * offsetG[i].z;
|
||||
}
|
||||
|
||||
// Extract chroma signal
|
||||
float chromaG[N];
|
||||
for (int j=0; j<N; j++) {
|
||||
chromaG[j] = 0.0;
|
||||
for (int i=0; i<N; i++) {
|
||||
chromaG[j] += tapG[i+j-(N-1)/2] * offsetG[i].w;
|
||||
}
|
||||
}
|
||||
|
||||
// B
|
||||
for (int i=0; i<N; i++) {
|
||||
float jB = float(i) - (float(N-1)/2.0);
|
||||
float kB = sinc( 2.0 * FC * jB) * window_blackman(float(i),float(N));
|
||||
offsetB[i] = vec4(jB/size.x, 0.0, kB, -kB);
|
||||
sumB += kB;
|
||||
}
|
||||
|
||||
// Low-pass filter input signal
|
||||
float tapB[N];
|
||||
for (int i=0; i<N; i++) {
|
||||
offsetB[i].zw /= sumB;
|
||||
tapB[i] = pulse(0.0, 1.0, uv.x + offsetB[i].x) * texture(Source, uv + offsetB[i].xy).b;
|
||||
}
|
||||
offsetB[(N-1)/2].w += 1.0;
|
||||
|
||||
// Extract luma signal
|
||||
float lumaB = 0.0;
|
||||
for (int i=0; i<N; i++) {
|
||||
lumaB += tapB[i] * offsetB[i].z;
|
||||
}
|
||||
|
||||
// Extract chroma signal
|
||||
float chromaB[N];
|
||||
for (int j=0; j<N; j++) {
|
||||
chromaB[j] = 0.0;
|
||||
for (int i=0; i<N; i++) {
|
||||
chromaB[j] += tapB[i+j-(N-1)/2] * offsetB[i].w;
|
||||
}
|
||||
}
|
||||
|
||||
// Generate YIQ signal R
|
||||
float YR = lumaR;
|
||||
float IR = 0.0;
|
||||
float QR = 0.0;
|
||||
for (int j=0; j<N; j++) {
|
||||
float subcarrierR = TAU * 0.25 * size.x * (uv.s + float(j+(N-1)/2)/size.x);
|
||||
IR += cos(subcarrierR) * chromaR[j] * offsetR[j].z;
|
||||
QR += sin(subcarrierR) * chromaR[j] * offsetR[j].z;
|
||||
}
|
||||
|
||||
// Generate YIQ signal G
|
||||
float YG = lumaG;
|
||||
float IG = 0.0;
|
||||
float QG = 0.0;
|
||||
for (int j=0; j<N; j++) {
|
||||
float subcarrierG = TAU * 0.25 * size.x * (uv.s + float(j+(N-1)/2)/size.x);
|
||||
IG += cos(subcarrierG) * chromaG[j] * offsetG[j].z;
|
||||
QG += sin(subcarrierG) * chromaG[j] * offsetG[j].z;
|
||||
}
|
||||
|
||||
// Generate YIQ signal B
|
||||
float YB = lumaB;
|
||||
float IB = 0.0;
|
||||
float QB = 0.0;
|
||||
for (int j=0; j<N; j++) {
|
||||
float subcarrierB = TAU * 0.25 * size.x * (uv.s + float(j+(N-1)/2)/size.x);
|
||||
IB += cos(subcarrierB) * chromaB[j] * offsetB[j].z;
|
||||
QB += sin(subcarrierB) * chromaB[j] * offsetB[j].z;
|
||||
}
|
||||
|
||||
// Apply TV adjustments to YIQ signal and convert to RGB
|
||||
FragColor.r = (YIQ2RGB * adjust(vec3(YR, IR, QR), HUE, SAT, BRI)).r;
|
||||
FragColor.g = (YIQ2RGB * adjust(vec3(YG, IG, QG), HUE, SAT, BRI)).g;
|
||||
FragColor.b = (YIQ2RGB * adjust(vec3(YB, IB, QB), HUE, SAT, BRI)).b;
|
||||
}
|
||||
Loading…
Reference in a new issue