6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2025-02-07 05:30:30 +00:00
Code Issues Projects Releases Wiki Activity

Attempts fully to restore composite video.

Browse Source 
Subject to some sort of nasty race condition for the time being.
This commit is contained in:
Thomas Harte 2020-09-02 08:03:10 -04:00
parent c36247b609
commit c7ce65ea4c
2 changed files with 50 additions and 43 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
OSBindings/Mac/Clock Signal/ScanTarget/CSScanTarget.mm
View File

@ -98,7 +98,8 @@ struct Uniforms {
simd::float3x3 fromRGB;
float zoom;
simd::float2 offset;
simd::float3 firCoefficients[8];
simd::float3 chromaCoefficients[8];
float lumaCoefficients[8];
float radiansPerPixel;
float cyclesMultiplier;
};
@ -560,32 +561,30 @@ using BufferingScanTarget = Outputs::Display::BufferingScanTarget;
_compositionRenderPass.colorAttachments[0].clearColor = MTLClearColorMake(0.0, 0.5, 0.5, 1.0);
// Create suitable FIR filters.
auto *const firCoefficients = uniforms()->firCoefficients;
_lineBufferPixelsPerLine = NSUInteger(modals.cycles_per_line) * NSUInteger(uniforms()->cyclesMultiplier);
const float colourCyclesPerLine = float(modals.colour_cycle_numerator) / float(modals.colour_cycle_denominator);
if(isSVideoOutput) {
// In S-Video, don't filter luminance.
for(size_t c = 0; c < 7; ++c) {
firCoefficients[c].x = 0.0f;
// Generate the chrominance filter.
{
auto *const chromaCoefficients = uniforms()->chromaCoefficients;
SignalProcessing::FIRFilter chrominancefilter(15, float(_lineBufferPixelsPerLine), 0.0f, colourCyclesPerLine * (isSVideoOutput ? 1.0f : 1.0f));
const auto calculatedCoefficients = chrominancefilter.get_coefficients();
for(size_t c = 0; c < 8; ++c) {
chromaCoefficients[c].y = chromaCoefficients[c].z = calculatedCoefficients[c] * (isSVideoOutput ? 4.0f : 8.0f);
chromaCoefficients[c].x = 0.0f;
}
firCoefficients[7].x = 1.0f;
} else {
// In composite, filter luminance gently.
chromaCoefficients[7].x = 1.0f;
}
// Generate the luminance filter.
{
auto *const luminanceCoefficients = uniforms()->lumaCoefficients;
SignalProcessing::FIRFilter luminancefilter(15, float(_lineBufferPixelsPerLine), 0.0f, colourCyclesPerLine * 0.5f);
const auto calculatedCoefficients = luminancefilter.get_coefficients();
for(size_t c = 0; c < 8; ++c) {
firCoefficients[c].x = calculatedCoefficients[c];
}
}
// Whether S-Video or composite, apply the same relatively strong filter to colour channels.
SignalProcessing::FIRFilter chrominancefilter(15, float(_lineBufferPixelsPerLine), 0.0f, colourCyclesPerLine * (isSVideoOutput ? 1.0f : 0.25f));
const auto calculatedCoefficients = chrominancefilter.get_coefficients();
for(size_t c = 0; c < 8; ++c) {
firCoefficients[c].y = firCoefficients[c].z = calculatedCoefficients[c] * (isSVideoOutput ? 4.0f : 4.0f);
memcpy(luminanceCoefficients, calculatedCoefficients.data(), sizeof(float)*8);
}
// Store radians per pixel. TODO: is this now orphaned? Should I keep it anyway?
uniforms()->radiansPerPixel = (colourCyclesPerLine * 3.141592654f * 2.0f) / float(_lineBufferPixelsPerLine);
}

56
OSBindings/Mac/Clock Signal/ScanTarget/ScanTarget.metal
View File

@ -32,9 +32,13 @@ struct Uniforms {
float zoom;
float2 offset;
// Describes the FIR filter in use; it'll be 15 coefficients but they're
// Describes the FIR filter in use for chroma filtering; it'll be
// 15 coefficients but they're symmetrical around the centre.
float3 chromaCoefficients[8];
// Describes the FIR filter in use for luma filtering; also 15 coefficients
// symmetrical around the centre.
float3 firCoefficients[8];
float lumaCoefficients[8];
// Maps from pixel offsets into the composition buffer to angular difference.
float radiansPerPixel;
@ -386,7 +390,7 @@ kernel void filterChromaKernel( texture2d<float, access::read> inTexture [[textu
inTexture.read(gid + uint2(14, offset)) - moveToZero,
};
#define Sample(x, y) uniforms.firCoefficients[y] * rawSamples[x].rgb
#define Sample(x, y) uniforms.chromaCoefficients[y] * rawSamples[x].rgb
const float3 colour =
Sample(0, 0) + Sample(1, 1) + Sample(2, 2) + Sample(3, 3) + Sample(4, 4) + Sample(5, 5) + Sample(6, 6) +
Sample(7, 7) +
@ -411,32 +415,36 @@ kernel void separateLumaKernel( texture2d<float, access::read> inTexture [[textu
uint2 gid [[thread_position_in_grid]],
constant Uniforms &uniforms [[buffer(0)]],
constant int &offset [[buffer(1)]]) {
// TODO!
constexpr float4 moveToZero = float4(0.0f, 0.5f, 0.5f, 0.0f);
const float4 rawSamples[] = {
inTexture.read(gid + uint2(0, offset)) - moveToZero,
inTexture.read(gid + uint2(1, offset)) - moveToZero,
inTexture.read(gid + uint2(2, offset)) - moveToZero,
inTexture.read(gid + uint2(3, offset)) - moveToZero,
inTexture.read(gid + uint2(4, offset)) - moveToZero,
inTexture.read(gid + uint2(5, offset)) - moveToZero,
inTexture.read(gid + uint2(6, offset)) - moveToZero,
inTexture.read(gid + uint2(7, offset)) - moveToZero,
inTexture.read(gid + uint2(8, offset)) - moveToZero,
inTexture.read(gid + uint2(9, offset)) - moveToZero,
inTexture.read(gid + uint2(10, offset)) - moveToZero,
inTexture.read(gid + uint2(11, offset)) - moveToZero,
inTexture.read(gid + uint2(12, offset)) - moveToZero,
inTexture.read(gid + uint2(13, offset)) - moveToZero,
inTexture.read(gid + uint2(14, offset)) - moveToZero,
const float4 centreSample = inTexture.read(gid + uint2(7, offset));
const float rawSamples[] = {
inTexture.read(gid + uint2(0, offset)).r,
inTexture.read(gid + uint2(1, offset)).r,
inTexture.read(gid + uint2(2, offset)).r,
inTexture.read(gid + uint2(3, offset)).r,
inTexture.read(gid + uint2(4, offset)).r,
inTexture.read(gid + uint2(5, offset)).r,
inTexture.read(gid + uint2(6, offset)).r,
centreSample.r,
inTexture.read(gid + uint2(8, offset)).r,
inTexture.read(gid + uint2(9, offset)).r,
inTexture.read(gid + uint2(10, offset)).r,
inTexture.read(gid + uint2(11, offset)).r,
inTexture.read(gid + uint2(12, offset)).r,
inTexture.read(gid + uint2(13, offset)).r,
inTexture.read(gid + uint2(14, offset)).r,
};
#define Sample(x, y) uniforms.firCoefficients[y] * rawSamples[x].rgb
const float3 colour =
#define Sample(x, y) uniforms.lumaCoefficients[y] * rawSamples[x]
const float luminance =
Sample(0, 0) + Sample(1, 1) + Sample(2, 2) + Sample(3, 3) + Sample(4, 4) + Sample(5, 5) + Sample(6, 6) +
Sample(7, 7) +
Sample(8, 6) + Sample(9, 5) + Sample(10, 4) + Sample(11, 3) + Sample(12, 2) + Sample(13, 1) + Sample(14, 0);
#undef Sample
outTexture.write(float4(uniforms.toRGB * colour, 1.0f), gid + uint2(7, offset));
outTexture.write(float4(
luminance,
(centreSample.gb - float2(0.5f)) * (centreSample.r - luminance) + float2(0.5f),
1.0f
),
gid + uint2(7, offset));
}