Blurring image with RGB values without convolving it with a kernel I'm  using an app for face redaction that doesn't allow access to the source code but only allows me to pass pixel values for red, green and blue channel upon which it creates a matrix with the same average RGB values for every ROI pixel value. For eg. if I give Red=32,Blue=123 and Green=233 it will assign these RGB values for every pixel of the ROI and then draws a colored patch on the face.

So I was wondering is there a general combination of RGB values of a pixel to distort it and make it look like it's blurred. I can also set the opacity value in the app.

Thanks.
Blurring an image depends on being able to read from the image. If you don’t have access to the pixel data, or external information about the image contents (e.g. average hue / luminance), there’s no way to find an overlay color that will look like you’ve blurred what it’s on top of.