Portable Network Graphics File Format (PNG)

 

General Description

The PNG format is intended to provide a portable, legally unencumbered, well-compressed, well-specified standard for lossless bitmapped image files.

 

PNG is highly recommended as a generalized format for image exchange.

 

The default extension is PNG.

 

Supporting Platforms and Applications

This format is supported by numerous applications on a wide range of platforms.

 

PMView Support

PMView supports the PNG format in full, according to PNG Specification Version 0.96 (11 Mar, 1996). We have coded all the routines from scratch and optimized the code for speed under OS/2, thus PMView does not use the public PNG-library.

 

Color Type and Bit Depth

 

Bit Depth  Interpretation    

0

1,2,4,8,16 

Grayscale images

2

8,16

RGB deep color images

3

1,2,4,8 

Colormapped images

4

8,16

RGB deep color images with alpha channel

6

8,16

Grayscale images with alpha channel

 

 

Compression Type

0  Deflate/inflate compression with 32K sliding window

 

Filter Type

0 Adaptive filtering with five basic filter types

 

Interlace Type

0 No interlace

1 Adam7 interlace