Portable Network Graphics

"PNG" redirects here. For the country, see Papua New Guinea.

Portable Network Graphics (often shortened to PNG) is a bitmapped image format that uses lossless data compression.

Their most common use is within transparent images, as it does support an alpha channel along with a 16-bit color channel.

Portable Network Graphics Media

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  PNG transparency demonstration 1

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  A demonstration of the colour depth in a PNG file, in bits per channel. Left: 8 bits; Right: 16 bits. Note the artifacts, adjusted contrast for clarity.

• PNG demo Banana.png

  Example with several types of image content

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  Representation of bit cost per pixel for above PNG file (red=expensive, blue=cheap)

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  PNG's filter method 0 can use the data in pixels A, B, and C to predict the value for X.

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  A PNG with 256 colors, which is only 269 bytes large with pre-filter. The same image as a GIF would be more than twelve times larger.

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  An illustration of Adam7 interlacing over a 16×16 image

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  An APNG (animated PNG) file (displays as static image in some web browsers)

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  Composite image comparing lossy compression in JPEG with lossless compression in PNG: the JPEG artifacts can be easily visible in the background of this kind of image data, where the PNG image has solid color.