2 and 4 byte compressor

This code has been declared by its author to be Public Domain code.

2 and 4 byte compressor by Skully

2001

Crunch2 turns a 2 byte (0-65535) value into a 2 byte string. Crunch 4 turns a 4 byte (0-4294967295) value into a 4 byte string.

Uncrunch2 and Uncrunch4 restore the original values.

This is good for compressing numerical values for storage in files or transfer over the network.

Function crunch2$(num)
	byte2=num Shr 8 And %11111111 
	byte1=num And %11111111
	Return Chr$(byte2)+Chr$(byte1)	
End Function

Function uncrunch2(bytes$)
	byte2=Asc(Left$(bytes,1)) Shl 8
	byte1=Asc(Right$(bytes,1))
	Return byte2 Or byte1
End Function

Function crunch4$(num)
	byte4=num Shr 24 And %11111111 
	byte3=num Shr 16 And %11111111 
	byte2=num Shr 8 And %11111111 
	byte1=num And %11111111 
	Return Chr$(byte4)+Chr$(byte3)+Chr$(byte2)+Chr$(byte1)	
End Function

Function uncrunch4(bytes$)
	byte4=Asc(Left$(bytes,1)) Shl 24
	byte3=Asc(Mid$(bytes,2,1)) Shl 16
	byte2=Asc(Mid$(bytes,3,1)) Shl 8
	byte1=Asc(Right$(bytes,1))
	Return byte4 Or byte3 Or byte2 Or byte1
End Function

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