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  1. Member
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    Hi, I have this vibrance shader, It has an srgb threshold which can be adjusted. But the shader affects all saturation levels/%. I would like to leave colors that have a saturation under 80% unaffected, and target the above 90% saturation pixels, with a smooth transition between them (80-90%). So the first condition is the srgb threshold and the 2nd condition would be the pixel saturation. From my understanding this shader already checks saturation levels but I don't know how this works. Any help would be appreciated
    side note: I don't understand shaders, I just want to make this one adjustment.

    Code:
    //!PARAM vibr 
    //!DESC Saturates/deSaturates 
    //!TYPE float 
    //!MINIMUM -1 
    -0.3  
    
    //!HOOK MAIN 
    //!BIND HOOKED 
    //!DESC Vibrance 
     
    #define CoefLuma vec4(0.2126, 0.7152, 0.0722, 0) //sRGB, HDTV 
    float Thresh = 45.0/255.0; 
    float w = 10.0/255.0; 
     
    vec4 hook() { 
    vec4 c0 = HOOKED_texOff(0); 
    float lum = (c0.r + c0.g + c0.b)/3.0; 
     
    float colorSat = max(max(c0.r, c0.g), c0.b) -min(min(c0.r, c0.g), c0.b); // >=0, 5 arithmetic
    vec3 sat = mix(vec3(dot(c0, CoefLuma)), c0.rgb, 1+vibr -colorSat*abs(vibr)); 
    float delta = smoothstep( Thresh-w, Thresh+w, lum); 
    c0.rgb = mix( sat, c0.rgb, delta); 
    return c0; 
    }
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  2. Start with something like this and go from there:

    //!PARAM vibr
    //!DESC Saturates/deSaturates
    //!TYPE float
    //!MINIMUM -1
    -0.3

    //!HOOK MAIN
    //!BIND HOOKED
    //!DESC Vibrance

    #define CoefLuma vec4(0.2126, 0.7152, 0.0722, 0) //sRGB, HDTV
    float Thresh = 45.0/255.0;
    float w = 10.0/255.0;

    vec4 hook() {
    vec4 c0 = HOOKED_texOff(0);

    // Calculate saturation of the pixel's color
    float colorSat = max(max(c0.r, c0.g), c0.b) - min(min(c0.r, c0.g), c0.b);

    // Check if saturation is above 90%
    if (colorSat > 0.9) {
    // Calculate luminance
    float lum = dot(c0.rgb, CoefLuma.rgb);

    // Calculate smoothstep value for transition between 80-90% saturation
    float smoothstepValue = smoothstep(0.8, 0.9, colorSat);

    // Calculate the adjusted saturation
    vec3 adjustedSaturation = mix(vec3(dot(c0.rgb, CoefLuma.rgb)), c0.rgb, 1.0 + vibr - colorSat * abs(vibr));

    // Apply the effect with smooth transition
    c0.rgb = mix(c0.rgb, adjustedSaturation, smoothstepValue);
    }
    else if (colorSat < 0.8) {
    // Leave colors with saturation under 80% unaffected
    return c0;
    }

    // Calculate luminance
    float lum = (c0.r + c0.g + c0.b) / 3.0;

    float delta = smoothstep(Thresh - w, Thresh + w, lum);
    c0.rgb = mix(vec3(dot(c0.rgb, CoefLuma.rgb)), c0.rgb, 1.0 + vibr - colorSat * abs(vibr));
    c0.rgb = mix(c0.rgb, c0.rgb, delta);

    return c0;
    }
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  3. Member
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    Thank you for your answer. I tried this out and there is no effect visible. The shader is running but I guess something is not working properly.
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  4. Any error messages?
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  5. Member
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    No, I use this in mpv, it is not capable of showing any error messages. But if there would be a code error, the shader wouldn't load at all. The shader is loaded and runs in the pipeline but there is no visible change/effect to the image.

    Here are some screenshots so you have a visual representation of what we are talking about

    This is how the shader worked before your tweaks, it targets the set srgb threshold "float Thresh = 45.0/255.0"
    Image
    [Attachment 78736 - Click to enlarge]

    This is the normal image without any shaders or when I run the shader with your tweaks
    Image
    [Attachment 78737 - Click to enlarge]

    Here you can see the saturation of the suit, it's at 98%, so it shuld be affected by the shader
    Image
    [Attachment 78738 - Click to enlarge]
    Last edited by geextah_2; 30th Apr 2024 at 12:23.
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  6. Member
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    Sorry, it works. I tested it with an HDR file instead of SDR, my bad. Do you know why it isn't working on HDR? The original shader worked on both.
    Last edited by geextah_2; 2nd May 2024 at 07:04.
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  7. Sorry, I had lost this thread.

    Give me a day or two to look into the HDR issue.
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  8. Member
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    No problem. That would be awesome, thank you

    This is an improved version, with less hard edges, better smoothstep
    Code:
    //!PARAM vibr
    //!DESC Saturates/deSaturates
    //!TYPE float
    //!MINIMUM -1
    -0.5
    
    //!HOOK MAIN
    //!BIND HOOKED
    //!DESC Vibrance
    
    #define CoefLuma vec4(0.2126, 0.7152, 0.0722, 0) //sRGB, HDTV
    float Thresh = 200.0/255.0;
    float w = 10.0/255.0;
    
    vec4 hook() {
    	vec4 c0 = HOOKED_texOff(0);
    	float lum = (c0.r + c0.g + c0.b)/3.0;
    
    	float colorSat = max(max(c0.r, c0.g), c0.b) - min(min(c0.r, c0.g), c0.b); 
    	vec3 sat = mix(vec3(dot(c0, CoefLuma)), c0.rgb, 1+vibr - colorSat*abs(vibr));
    	float delta = smoothstep(Thresh-w, Thresh+w, lum);
    	sat = mix(sat, c0.rgb, delta);
    	delta = smoothstep(0.8, 0.9, colorSat);
    	c0.rgb = mix(c0.rgb, sat, delta);
    	return c0;
    }
    Here you can see the comparison

    Hard edge
    Image
    [Attachment 78852 - Click to enlarge]


    Smooth
    Image
    [Attachment 78853 - Click to enlarge]
    Last edited by geextah_2; 5th May 2024 at 08:20.
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