The output is a pixel value at (100,50)th position. Img = cv2.imread('/home/img/python.png', cv2.IMREAD_UNCHANGED) The pixel data must contain data corresponding to the four channels. We then print the pixel data at a position. In the following program, we read a PNG format image located at '/home/img/python.png' using imread() function. cv2.imread('/path/to/image/', cv2.IMREAD_UNCHANGED) Example You can read the source code of stbimage or libpng to see this for yourself. It's a compressed file format so there are no raw bytes you can supply to glTexImage. In case of error, the stbiload function returns NULL. If you want to load the image as is, pass 0 as the last parameter of the load function. To read PNG images with transparency (alpha) channel, use cv2.IMREAD_UNCHANGED as second argument in cv2.imread() function as shown in the following. The reason why libraries are recommended for PNG loading is because it's significantly more complex than BMP or TGA. The last argument of the function is useful if for example you want to load only the R, G, B channels from a four channel, PNG, image and ignore the transparency channel. 6.Test the exported png in an application that accepts pngs. Choose File> Export > Export as Quick PNG. use a paint brush and draw something on the mask layer. in the layers panel hit the layer mask button on that layer. Any transparency present in the image is not read. open a regular png with no alpha channel in photoshop. The syntax of imread() function contains a second argument whose default value is cv2.IMREAD_COLOR. Three color channels for red, green and blue, and the fourth channel is for transparency, also called alpha channel. OpenCV Python – Read PNG images with Transparency (or Alpha) Channel  Just to be clear, you're simply trying to load a png with an alpha channel?  I think your biggest concern here is that you're using SDL_DisplayFormat() instead of SDL_DisplayFormatAlpha().In this OpenCV tutorial using Python, we will learn how to read a PNG image with transparency or alpha channel. It looks like you're trying to do something fancy, but SDL_image does it for you.        surface = SDL_DisplayFormatAlpha(image) ![]()  Just to be clear, you're simply trying to load a png with an alpha channel?  I think your biggest concern here is that you're using SDL_DisplayFormat() instead of SDL_DisplayFormatAlpha(). I just actually got to the part of loading and plotting and i set them to have mask black, which works on the un-previously edited ones, pngs seem to be able to remember what was underneath the transparency so some images work fine with black set and some still have remnants of previous editing, but it would still be nice to be able to know how to load pngs with proper alpha so certain parts of the images are semi transparent etc. ![]() SDL_Surface *getimage(int alpha, int mask, char *name) My image loading function looks like this ( i only use png's ) I have some pngs where in gimp i already set the background as transparent for a flash game, which loads the images with the transparent bits, there are ways to set transparency after you loaded but its a pain, anyways, so i have all the images and all i really want to do is load them as they appear in gimp with all their transparent bits intact.  The surface will store this info and an extra byte (for 32-bit pngs) per pixel to store the alpha at that pixel.  That's just part of the description of the pixel representation. Do you mean the surface's Amask?  Yeah, it works.
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