OVERLAY IMAGES WITH TRANSPARENCY PYTHON HOW TO
OVERLAY IMAGES WITH TRANSPARENCY PYTHON CODE

We’ll then create a NumPy array with the same dimension as the background image, with all values as 0. For this program to work, first we’ll need two inputs: Background Image, Overlay Image.

OVERLAY IMAGES WITH TRANSPARENCY PYTHON HOW TO

Img2 = plt. In this article, we are going to see how to Transparent overlays with Python OpenCV. # here it is progressive, but you can create whathever you want # create your alpha array and fill the colormap with them. Then, you can fill the alpha values according to what you want to achieve (in your example, create an array from 0 to 0.8)īelow is an example using your code: from lors import colorConverter.Then initialize this colormap object: this will cause it to internally create an array called '_lut' which holds rgba values.

Or create your own colormap as you did, if the colormap you want doesn't already exist. First, choose a matplotlib colormap object (in your case, for white and black, you can take the 'binary' colormap).Here is a description of what you can do: In your example, img3 = plt.imshow(zvals2, interpolation='nearest', cmap=cmap2, origin='lower', alpha=0.6) EDIT: You can set the alpha argument in your imshow command. That one worked for me, but its very slow. Something like this: I haven't been able to find any solution, so I decided to go pixel by pixel and calculate the resulting color.

from PIL import Image, ImageDraw from io import BytesIO from urllib.request import urlopen TINTCOLOR (0, 0, 0) Black TRANSPARENCY. Note that it supports semi-transparent squares other than black.

OVERLAY IMAGES WITH TRANSPARENCY PYTHON CODE

What I'm trying to achieve is to place an image with transparency on top of another one. You can do it by creating a temporary image and using Image.alphacomposite () as shown in the code below. I also tried the colorConverter method to set the color in a normal plt.plot situation and the color also did not become transparent though the correct color was displayed.Īny additional advice on how to overlay/compare imshow plots would be much appreciated Python OpenCV - overlay an image with transparency. There is no error but the white and black of the second plot do not show any transparency. Img3 = plt.imshow(zvals2,interpolation='nearest',cmap=cmap2,origin='lower') Img2 = plt.imshow(zvals,interpolation='nearest',cmap=cmap1,origin='lower') My first instinct is to make the colors in the colormap transparent (the lower values especially) but I haven't been able to get this to work: from lors import colorConverterĬolor1 = colorConverter.to_rgba('white',alpha=0.0)Ĭolor2 = colorConverter.to_rgba('black',alpha=0.8)Ĭmap1 = _list('my_cmap',256)Ĭmap2 = _list('my_cmap2',256)

For example, if a pixel is 192 in image1 and 67 in image2, the ImageChops.lighter() method will result in 192, whereas the paste() method will see there is something in image2, and therefore give you the 67.I would like to compare two different sets of data on the same imshow plot to make it easy to see the differences. Note that these two methods will give subtly different results. I just think the ImageChops.lighter() method is simpler. # Paste image2 into image1 only where image2 has non-black content Mask = mask.point(lambda i: 255 if i>0 else 0) That might look like this: im1 = Image.open('test1.jpeg') In order to avoid that, you would need to make a mask and only paste where image2 is non-zero. Note that you could use paste() as you originally intended, but that it will paste all the black as well as the white pixels from image2 over image1. # Choose lighter of the two images at each pixel location You simply need to choose the lighter of your two images at each point with PIL Channel Operations: from PIL import Image, ImageChops

Overlay images with transparency python