strings
strings -n 6 file: Extract the strings with min length of 6
strings -n 6 file | head -n 20: Extract first 20 strings with min length of 6
strings -n 6 file | tail -n 20: Extract last 20 strings with min length of 6
strings -e s -n 6 file: Extract 7bit strings
strings -e S -n 6 file: Extract 8bit strings
strings -e l -n 6 file: Extract 16bit strings (little-endian)
strings -e b -n 6 file: Extract 16bit strings (big-endian)
strings -e L -n 6 file: Extract 32bit strings (little-endian)
strings -e B -n 6 file: Extract 32bit strings (big-endian)
binwalk
binwalk <file-name>
binwalk -e <file-name>
exiv2
exiv2 <file-name>
exiftool <file-name>
steghide
steghide --extract -sf <file-name>
zbarimg for QR codes
zbarimg QR-code.png
stegsolve
wget http://www.caesum.com/handbook/Stegsolve.jar -O stegsolve.jar
chmod +x stegsolve.jar
java -jar stegsolve.jar
hexedit
hexedit <file-name>