![]() ![]() Int defaultTextViewColor = textView.getTextColors(). ![]() int rgba_color = Color.parseColor("#8a000000") //textViewColor Here is some java code (works on Android API 24): //int rgb_background = Color.parseColor("#ffffff") //white background If the color is in non pre-multiplied color-space, then you can just discard the alpha channel. If the RGBA is in pre-multiplied color-space and is semi-transparent, you need to divide out alpha to get the correct RGB color. In my case, I wanted to convert an RGBA image to RGB and the following worked just as expected: rgbImage = cv2.cvtColor(npimage, cv2.COLOR_RGBA2RGB) version rgba(0,0,0,0) with matte rgb(ff,ff,ff) will be changed to rgb(0,0,0). This changed version works fine for me, because in prev. Solution provided by Andras Zoltan should be slightly changed to: Source => Target = (BGColor + Source) = To get the final 0-255 values for Target you simply multiply all the normalised values back up by 255, making sure you cap at 255 if any of the combined values exceed 1.0 (this is over-exposure and there are more complex algorithms dealing with this that involve whole-image processing etc.).ĮDIT: In your question you said you want a white background - in that case just fix BGColor to 255,255,255. Target.B = ((1 - Source.A) * BGColor.B) + (Source.A * Source.B) Target.G = ((1 - Source.A) * BGColor.G) + (Source.A * Source.G) Target.R = ((1 - Source.A) * BGColor.R) + (Source.A * Source.R) Now, the conversion is defined as (in complete psuedo code here!): Source => Target = (BGColor + Source) = We'll call the result BGColor Note - if the background colour is also transparent, then you'll have to recurse the process for that first (again, choosing a matte) to get the source RGB for this operation. Normalise also the matte colour (black, white whatever).Normalise the RGBA values so that they're all between 0 and 1 - just divide each value by 255 to do this.There is an algorithm for this (from this wikipedia link): This ends up being equal to answer below *Ī more specific answer, however, incorporates the alpha value into the actual colour result based on an opaque background colour (or 'matte' as it's referred to). I've therefore updated the formula below to be correct for the normal case. By definition, however, this won't work in most cases. It worked if alpha values were inverted from the normal. * A few comments have been raised that my original answer was not correct. color: □ Javascript color conversion and manipulation library.I've upvoted Johannes' answer because he's right about that.Use the Copy button to copy the HEX code to your clipboard.Otherwise, you'll get an error message.The HEX color code will appear if the code you supplied is valid. ![]() Press the Enter key or click the Convert button. ![]()
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