SYNOPSIS

pngchunks file

DESCRIPTION

pngchunks is a program that displays informations from files created according to the Portable Network Graphics file format.

EXAMPLE

pngchunks input.png Chunk: Data Length 13 (max 2147483647), Type 1380206665 [IHDR]

  Critical, public, PNG 1.2 compliant, unsafe to copy
  IHDR Width: 256
  IHDR Height: 256
  IHDR Bitdepth: 8
  IHDR Colortype: 2
  IHDR Compression: 0
  IHDR Filter: 0
  IHDR Interlace: 0
  IHDR Compression algorithm is Deflate
  IHDR Filter method is type zero (None, Sub, Up, Average, Paeth)
  IHDR Interlacing is disabled
  Chunk CRC: -753909967

Chunk: Data Length 6 (max 2147483647), Type 1145523042 [bKGD]

  Ancillary, public, PNG 1.2 compliant, unsafe to copy
  ... Unknown chunk type
  Chunk CRC: 554438993

Chunk: Data Length 9 (max 2147483647), Type 1935231088 [pHYs]

  Ancillary, public, PNG 1.2 compliant, safe to copy
  ... Unknown chunk type
  Chunk CRC: -757235972

Chunk: Data Length 7 (max 2147483647), Type 1162692980 [tIME]

  Ancillary, public, PNG 1.2 compliant, unsafe to copy
  ... Unknown chunk type
  Chunk CRC: 429243611

Chunk: Data Length 831 (max 2147483647), Type 1413563465 [IDAT]

  Critical, public, PNG 1.2 compliant, unsafe to copy
  IDAT contains image data
  Chunk CRC: 1406256926

Chunk: Data Length 0 (max 2147483647), Type 1145980233 [IEND]

  Critical, public, PNG 1.2 compliant, unsafe to copy
  IEND contains no data
  Chunk CRC: -1371381630

RELATED TO pngchunks…

AUTHOR

pngchunks was written by Michael Still <[email protected]>.

This manual page was written by Nelson A. de Oliveira <[email protected]>, for the Debian project (but may be used by others).