varying vec2 textureCoordinate;
varying vec2 textureCoordinate2;

uniform sampler2D inputImageTexture;
uniform sampler2D inputImageTexture2;

void main()
{
    vec4 textureColor = texture2D(inputImageTexture, textureCoordinate);
    vec4 textureColor2 = texture2D(inputImageTexture2, textureCoordinate2);
    gl_FragColor = vec4(abs(textureColor2.rgb - textureColor.rgb), textureColor.a);
}