Ruby

Compress and Decompress Hex String

See more Compression Examples

Imagine we have data represented as a hex string. This example demonstrates how to decode, compress, and re-encode to a smaller hex string representing the compressed data. An even better choice is to re-encode to a more compact encoding such as base64.

Note: This example requires Chilkat v9.5.0.66 or greater.

Ruby

require 'chilkat'

success = false

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

strHex = "54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A0D0A"

compress = Chilkat::CkCompression.new()
compress.put_Algorithm("deflate")

binDat = Chilkat::CkBinData.new()
# Load the hex string into a BinData object.
# This decodes the hexidecimal. The decoded bytes will be contained in the BinData.
binDat.AppendEncoded(strHex,"hex")

# Compress the BinData.
compress.CompressBd(binDat)

# Get the compressed data in hex format:
compressedHex = binDat.getEncoded("hex")
print "compressed hex:" + "\n";
print compressedHex + "\n";

# The compressed hex is: 0BC94855282CCD4CCE56482ACA2FCF5348CBAF50C82ACD2D484D51C82F4B2D522801CAE72456552AA4E4A7EBF172850C61E5BC5C00

# Even better, get the compressed data in base64 format:
# (base64url and modbase64 are other valid choices...)
compressedBase64 = binDat.getEncoded("base64")
print "compressed base64:" + "\n";
print compressedBase64 + "\n";

# The compressed base64 is: C8lIVSgszUzOVkgqyi/PU0jLr1DIKs0tSE1RyC9LLVIoAcrnJFZVKqTkp+vxcoUMYeW8XAA=

# Now decompress:
binDat.Clear()
binDat.AppendEncoded(compressedHex,"hex")
compress.DecompressBd(binDat)

decompressedHex = binDat.getEncoded("hex")
print "decompressed hex:" + "\n";
print decompressedHex + "\n";

# The output is the original hex string:
# 54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A54686520717569636B2062726F776E20666F78206A756D706564206F76657220746865206C617A7920646F672E0D0A0D0A