Search Results for "alpha channel"

"The type of a PNG image is defined in the IHDR image header. The image has a certain bit depth, up to 16 bits per sample, and a certain color type, from Grayscale to RGB+Alpha. If two PNG files of different types represent exactly the same image, each file can be regarded as a lossless transformation of the other. A lossless transformation can reduce the uncompressed stream, and such a transformation is named image reduction. In most cases, image reductions are capable of reducing the compressed stream (which is, in fact, our interest), as an indirect

Bill Bither likes the PNG format for graphics. In the start of his article, he lays out some of the nifty features that separate it from GIF and TIFF file formats. But there's more. "However, perhaps the best thing a PNG has to offer is what's called the alpha channel. An alpha channel is one byte of extra data per pixel (or palette entry for 8-bit images) that represents the transparency level of a pixel. A PNG image with alpha is capable of 256 levels of transparency. What does all this mean? For one thing, you can antialias text and images so