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Temporarily disabled my attempt to be clever with bilinear filtering when applying a lowpass filter. Will need to investigate.

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This commit is contained in:
Thomas Harte 2017-01-04 08:06:18 -05:00
parent aa7774a9a6
commit c746a3711f
3 changed files with 70 additions and 56 deletions
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2
Outputs/CRT/Internals/CRTOpenGL.cpp
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@ -393,7 +393,7 @@ void OpenGLOutputBuilder::set_timing_uniforms()
if(composite_y_filter_shader_program_)
{
composite_y_filter_shader_program_->set_width_scalers(output_width, output_width);
composite_y_filter_shader_program_->set_filter_coefficients(sample_cycles_per_line, colour_subcarrier_frequency * 0.25f);
composite_y_filter_shader_program_->set_filter_coefficients(sample_cycles_per_line, colour_subcarrier_frequency);
}
if(composite_chrominance_filter_shader_program_)
{

122
Outputs/CRT/Internals/Shaders/IntermediateShader.cpp
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@ -193,6 +193,7 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_chroma_luma_separat
"void main(void)"
"{"
// grab 11 samples
"vec4 samples[3] = vec4[]("
"vec4("
"texture(texID, inputPositionsVarying[0]).r,"
@ -214,6 +215,7 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_chroma_luma_separat
")"
");"
// apply the low-pass filter to separate luma
"float luminance = "
"dot(vec3("
"dot(samples[0], weights[0]),"
@ -221,9 +223,12 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_chroma_luma_separat
"dot(samples[2], weights[2])"
"), vec3(1.0));"
// define chroma to be whatever was here, minus luma
"float chrominance = 0.5 * (samples[1].y - luminance) / phaseAndAmplitudeVarying.y;"
"luminance /= (1.0 - phaseAndAmplitudeVarying.y);"
// split choma colours here, as the most direct place, writing out
// RGB = (luma, chroma.x, chroma.y)
"vec2 quadrature = vec2(cos(phaseAndAmplitudeVarying.x), -sin(phaseAndAmplitudeVarying.x));"
"fragColour = vec3(luminance, vec2(0.5) + (chrominance * quadrature));"
"}",false, false);
@ -302,35 +307,35 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_luma_filter_shader(
"void main(void)"
"{"
// "vec3 samples[] = vec3[]("
// "texture(texID, inputPositionsVarying[0]).rgb,"
// "texture(texID, inputPositionsVarying[1]).rgb,"
// "texture(texID, inputPositionsVarying[2]).rgb,"
// "texture(texID, inputPositionsVarying[3]).rgb,"
// "texture(texID, inputPositionsVarying[4]).rgb,"
// "texture(texID, inputPositionsVarying[5]).rgb,"
// "texture(texID, inputPositionsVarying[6]).rgb,"
// "texture(texID, inputPositionsVarying[7]).rgb,"
// "texture(texID, inputPositionsVarying[8]).rgb,"
// "texture(texID, inputPositionsVarying[9]).rgb,"
// "texture(texID, inputPositionsVarying[10]).rgb"
// ");"
//
// "vec4 luminance[] = vec4[]("
// "vec4(samples[0].r, samples[1].r, samples[2].r, samples[3].r),"
// "vec4(samples[4].r, samples[5].r, samples[6].r, samples[7].r),"
// "vec4(samples[8].r, samples[9].r, samples[10].r, 0.0)"
// ");"
"vec3 samples[] = vec3[]("
"texture(texID, inputPositionsVarying[0]).rgb,"
"texture(texID, inputPositionsVarying[1]).rgb,"
"texture(texID, inputPositionsVarying[2]).rgb,"
"texture(texID, inputPositionsVarying[3]).rgb,"
"texture(texID, inputPositionsVarying[4]).rgb,"
"texture(texID, inputPositionsVarying[5]).rgb,"
"texture(texID, inputPositionsVarying[6]).rgb,"
"texture(texID, inputPositionsVarying[7]).rgb,"
"texture(texID, inputPositionsVarying[8]).rgb,"
"texture(texID, inputPositionsVarying[9]).rgb,"
"texture(texID, inputPositionsVarying[10]).rgb"
");"
// "fragColour = vec3("
// "dot(vec3("
// "dot(luminance[0], weights[0]),"
// "dot(luminance[1], weights[1]),"
// "dot(luminance[2], weights[2])"
// "), vec3(1.0)),"
// "samples[5].gb"
// ");"
"fragColour = texture(texID, inputPositionsVarying[5]).rgb;"//lumaChromaToRGB * lumaChromaColourInRange;"
"vec4 luminance[] = vec4[]("
"vec4(samples[0].r, samples[1].r, samples[2].r, samples[3].r),"
"vec4(samples[4].r, samples[5].r, samples[6].r, samples[7].r),"
"vec4(samples[8].r, samples[9].r, samples[10].r, 0.0)"
");"
"fragColour = vec3("
"dot(vec3("
"dot(luminance[0], weights[0]),"
"dot(luminance[1], weights[1]),"
"dot(luminance[2], weights[2])"
"), vec3(1.0)),"
"samples[5].gb"
");"
// "fragColour = texture(texID, inputPositionsVarying[5]).rgb;"//lumaChromaToRGB * lumaChromaColourInRange;"
"}", false, false);
}
@ -418,44 +423,53 @@ void IntermediateShader::set_filter_coefficients(float sampling_rate, float cuto
// Perform a linear search for the highest number of taps we can use with 11 samples.
GLfloat weights[12];
GLfloat offsets[5];
unsigned int taps = 21;
unsigned int taps = 11;
// unsigned int taps = 21;
while(1)
{
float coefficients[21];
SignalProcessing::FIRFilter luminance_filter(taps, sampling_rate, 0.0f, cutoff_frequency, SignalProcessing::FIRFilter::DefaultAttenuation);
luminance_filter.get_coefficients(coefficients);
int sample = 0;
int c = 0;
// int sample = 0;
// int c = 0;
memset(weights, 0, sizeof(float)*12);
memset(offsets, 0, sizeof(float)*5);
int halfSize = (taps >> 1);
while(c < halfSize && sample < 5)
for(int c = 0; c < taps; c++)
{
offsets[sample] = (float)(halfSize - c);
if((coefficients[c] < 0.0f) == (coefficients[c+1] < 0.0f) && c+1 < (taps >> 1))
{
weights[sample] = coefficients[c] + coefficients[c+1];
offsets[sample] -= (coefficients[c+1] / weights[sample]);
c += 2;
}
else
{
weights[sample] = coefficients[c];
c++;
}
sample ++;
}
if(c == halfSize) // i.e. we finished combining inputs before we ran out of space
{
weights[sample] = coefficients[c];
for(int c = 0; c < sample; c++)
{
weights[sample+c+1] = weights[sample-c-1];
}
break;
if(c < 5) offsets[c] = (halfSize - c);
weights[c] = coefficients[c];
}
break;
// int halfSize = (taps >> 1);
// while(c < halfSize && sample < 5)
// {
// offsets[sample] = (float)(halfSize - c);
// if((coefficients[c] < 0.0f) == (coefficients[c+1] < 0.0f) && c+1 < (taps >> 1))
// {
// weights[sample] = coefficients[c] + coefficients[c+1];
// offsets[sample] -= (coefficients[c+1] / weights[sample]);
// c += 2;
// }
// else
// {
// weights[sample] = coefficients[c];
// c++;
// }
// sample ++;
// }
// if(c == halfSize) // i.e. we finished combining inputs before we ran out of space
// {
// weights[sample] = coefficients[c];
// for(int c = 0; c < sample; c++)
// {
// weights[sample+c+1] = weights[sample-c-1];
// }
// break;
// }
taps -= 2;
}

2
Outputs/CRT/Internals/TextureTarget.cpp
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@ -34,7 +34,7 @@ TextureTarget::TextureTarget(GLsizei width, GLsizei height, GLenum texture_unit)
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, (GLsizei)_expanded_width, (GLsizei)_expanded_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, blank_buffer);
free(blank_buffer);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, _texture, 0);