PGF (Progressive Graphics File) is a wavelet-based bitmapped image format that employs lossless and lossy data compression.

[citation needed] PGF can operate at higher compression ratios without taking more encoding/decoding time and without generating the characteristic "blocky and blurry" artifacts of the original DCT-based JPEG standard.

After the wavelet transform, the coefficients are scalar-quantized to reduce the amount of bits to represent them, at the expense of a loss of quality.

They are typically selected in a way that the coefficients within them across the sub-bands form approximately spatial blocks in the (reconstructed) image domain and collected in a fixed size macroblock.

The RLR coder with parameter k (logarithmic length of a run of zeros) is also known as the elementary Golomb code of order 2k.

There are several self-proclaimed advantages of PGF over the ordinary JPEG standard:[2] The author published libPGF via a SourceForge, under the GNU Lesser General Public License version 2.0.

Other WIC applications including File Explorer are able to display PGF images after installing this viewer.