obs-StreamFX/data/effects/standard.effect

#include "shared.effect"

uniform texture2D Channel0;
uniform texture2D Channel1;

//------------------------------------------------------------------------------
// Technique: Restore Alpha
//------------------------------------------------------------------------------
// Parameters:
// - Channel0: RGBX Texture
// - Channel1: XXXA Texture

float4 PSRestoreAlpha(VertexData vtx) : TARGET {
	float4 rgbx = Channel0.Sample(BlankSampler, vtx.uv);
	float4 xxxa = Channel1.Sample(BlankSampler, vtx.uv);
	rgbx.a = xxxa.a;
	return rgbx;
};

technique RestoreAlpha
{
	pass
	{
		vertex_shader = DefaultVertexShader(vtx);
		pixel_shader = PSRestoreAlpha(vtx);
	};
};