What is a PNG file?

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What is a PNG file?
PNG or Portable Network Graphics files are image files commonly used for the Web. They are designed to replace older graphics formats like GIF (graphic interchange format).

PNG files are said to allow more color support, so images may have different hues from opaque status to transparent status. GIF formats only allow images to be fully opaque or fully transparent and nothing in between. PNG files also don’t have any limitations in terms of copyright issues, unlike its GIF counterpart.

Overall, PNG has three distinct advantages over GIF file formats. First is on the alpha channels, where image transparency may be modified. With this capability, some pixels may have high transparency of 80%, while other pixels may also be adjusted to a lower degree. Having alpha channels also allow for making shadows using colors of the user’s choosing. Next advantage is on gamma correction, wherein graphic brightness and saturation may be controlled on cross-platforms. This feature makes sure that images don’t’ look too bright on the computer’s monitor because of adjustments made on the color value. The third advantage is PNG’s capability for 2D-interlacing for image display.

In terms of file compression, PNG files also have the advantage over GIF files. Without having to pay for patent fees, compression may be done without the fear of lost graphic info or specifications. PNG also supports palette-based, truecolor, and grayscale types. JPEG files meanwhile cannot support palette-based types while GIF formats only support this type. In PNG files, the compression is said to be “lossless”, so no image information is lost, resulting to better image quality.

PNG image files don’t have animation capabilities though, unlike GIF formats. And since the PNG image format was designed for Web viewing, it also does not support the CMYK color scheme which is widely used for professional graphic viewing and editing. But when it comes to the web, most browsers today now have support for PNG graphic file format.


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