Merge pull request #196 from hunterk/interlacing

update bob-deinterlacing and remove now-redundant bob-and-ghost

misc/bob-and-ghost-deinterlacing.slang

@@ -1,63 +0,0 @@
-#version 450
-
-/*
-   Bob-and-ghost Deinterlacing
-   Author: hunterk
-   License: Public domain
-   
-   Note: This shader is designed to work with the typical interlaced output from an emulator, which displays both even and odd fields twice.
-   As such, it is inappropriate for general video use unless the video has already been similarly woven beforehand.
-*/
-
-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;
-
-void main()
-{
-	vec4 current = pow(texture(Source, vTexCoord.xy), vec4(2.2));
-	vec4 prev  = vec4(0.0);
-	float y = 0.0;
-	// assume anything with a vertical resolution greater than 400 lines is interlaced
-	if (params.SourceSize.y > 400.0){
-		y = params.SourceSize.y * vTexCoord.y + params.FrameCount;
-		current = pow(vec4(texture(Source, vTexCoord + vec2(0.0, params.SourceSize.w))), vec4(2.2));
-		vec4 evens = pow(vec4(texture(Source, vTexCoord - vec2(0.0, 0.5 * params.SourceSize.w))), vec4(2.2));
-		vec4 odds = pow(vec4(texture(Source, vTexCoord + vec2(0.0, 0.5 * params.SourceSize.w))), vec4(2.2));
-		prev = (evens + odds) / 2.0;
-	}
-	else
-	{
-		y = 2.000001 * params.SourceSize.y * vTexCoord.y;
-		prev = current;
-	}
-
-	if (mod(y, 2.0) > 0.99999) current = current;
-	else current = vec4(pow(texture(Source, vTexCoord), vec4(2.2)));
-	FragColor = vec4(pow((current + prev) / vec4(2.0), vec4(1.0 / 2.2)));
-}

misc/bob-deinterlacing.slang

@@ -5,8 +5,11 @@
    Author: hunterk
    License: Public domain
    
-   Note: This shader is designed to work with the typical interlaced output from an emulator, which displays both even and odd fields twice.
+   Note: This shader is designed to work with the typical interlaced output from
-   As such, it is inappropriate for general video use unless the video has already been similarly woven beforehand.
+   an emulator, which displays both even and odd fields twice.
+   
+   As such, it is inappropriate for general video use unless the video has
+   already been similarly woven beforehand.
 */
 
 layout(push_constant) uniform Push
@@ -15,6 +18,7 @@ layout(push_constant) uniform Push
 	vec4 OriginalSize;
 	vec4 OutputSize;
 	uint FrameCount;
+	float scale, ghost;
 } params;
 
 layout(std140, set = 0, binding = 0) uniform UBO
@@ -22,30 +26,62 @@ layout(std140, set = 0, binding = 0) uniform UBO
 	mat4 MVP;
 } global;
 
+// I wish there were some way to make this automatic...
+#pragma parameter scale "Deinterlacing Scale" 1.0 1.0 16.0 1.0
+
+#pragma parameter ghost "Blend Frames to Hide Bobbing" 0.0 0.0 1.0 1.0
+
 #pragma stage vertex
 layout(location = 0) in vec4 Position;
 layout(location = 1) in vec2 TexCoord;
 layout(location = 0) out vec2 vTexCoord;
+layout(location = 1) out float is_interlaced;
 
 void main()
 {
    gl_Position = global.MVP * Position;
    vTexCoord = TexCoord;
+   is_interlaced = float(params.OriginalSize.y > 400.0 * params.scale);
 }
 
 #pragma stage fragment
 layout(location = 0) in vec2 vTexCoord;
+layout(location = 1) in float is_interlaced;
 layout(location = 0) out vec4 FragColor;
 layout(set = 0, binding = 2) uniform sampler2D Source;
+layout(set = 0, binding = 3) uniform sampler2D OriginalHistory1;
 
 void main()
 {
-	float y = 0.0;
+   // snap to the center of the underlying texel
-	// assume anything with a vertical resolution greater than 400 lines is interlaced
+   vec2 uv = vTexCoord * params.SourceSize.xy - 0.5;
-	if (params.SourceSize.y > 400.0) y = params.SourceSize.y * vTexCoord.y + float(params.FrameCount);
+   uv = (floor(uv) + 0.5) * params.SourceSize.zw;
-	else	y = 2.000001 * params.SourceSize.y * vTexCoord.y;
    
-	if (mod(y, 2.0) > 0.99999) FragColor = vec4(texture(Source, vTexCoord + vec2(0.0, params.SourceSize.w)));
+   // go ahead and sample the texture and early return if not interlaced
-	else
+	vec4 current = texture(Source, uv);
-	FragColor = vec4(texture(Source, vTexCoord).rgb, 1.0);
+	FragColor = current;
+	if(!bool(is_interlaced)) return;
+   
+   float scale = params.scale;
+
+	// work our way down the vertical axis and skip up 1 pixel every other frame
+	float y = (params.SourceSize.y / scale) * uv.y + mod(float(params.FrameCount), 2.0);
+	
+	// deinterlace the current frame
+	vec4 offset = texture(Source, uv + vec2(0.0, params.SourceSize.w * scale));
+	vec4 deint_current = (mod(y, 2.0) > 0.99999) ? offset : current;
+	
+	FragColor = deint_current;
+	// early return if we don't want to do any frame-blending
+	if(!bool(params.ghost)) return;
+	
+	// previous frame needs an opposite tick from the current frame
+	float y2 = (params.SourceSize.y / scale) * uv.y + clamp(1.0 - mod(float(params.FrameCount), 2.0), 0.0, 1.0);
+	
+	// deinterlace previous frame
+	vec4 prev = texture(OriginalHistory1, uv);
+	vec4 prev_offset = texture(OriginalHistory1, uv + vec2(0.0, params.SourceSize.w * scale));
+	vec4 deint_prev = (mod(y2, 2.0) > 0.99999) ? prev_offset : prev;
+	
+	FragColor = mix(deint_current, deint_prev, 0.5);
 }