Image forensics

steganography 

Tools and tips

• strings, file [bash]
• cat[only works for embedded txt files]
• exiftool
• stegsolve [here]
• zsteg [here]
• gimp [Color> Set color maps>palette]
• unzip [use 7za if it fails]
• binwalk (files in image, not zip) [binwalk]
• Any hex editor [check google for mandatory image field, optional fields may have flags ]
  ubuntu - wxhexeditor, bless
  windows -Hxd hex editor
• Look at headers(chunks,pixels,optional headers,end of file IEND)
• Change width,height bytes [output visible in windows only]
• PNG Filter type extraction: https://github.com/f1nsternacht/libpng
  
  References :
  https://www.youtube.com/watch?v=KUZVIBXfoeA
  http://www.libpng.org/pub/png/spec/1.2/PNG-Contents.html
  https://www.guillermito2.net/stegano/