(Ruby) Compress Large Binary File in Blocks

Compresses a large binary file in blocks. This example uses BeginCompressBytes, MoreCompressBytes, and EndCompressBytes.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

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

facSrc = Chilkat::CkFileAccess.new()
facDest = Chilkat::CkFileAccess.new()

# Open a large binary file for reading.
success = facSrc.OpenForRead("qa_data/bmp/big.bmp")
if (success != true)
    print facSrc.lastErrorText() + "\n";
    exit
end

# If we compress in 64K chunks, find out how many blocks there will be.
blockSize = 65536
numBlocks = facSrc.GetNumBlocks(blockSize)

# Open an output file for the compressed data.
success = facDest.OpenForWrite("qa_data/bmp/compressedBmp.dat")
if (success != true)
    print facDest.lastErrorText() + "\n";
    exit
end

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

fileBytes = Chilkat::CkByteData.new()
compressedBytes = Chilkat::CkByteData.new()

i = 0
while i < numBlocks
    success = facSrc.ReadBlock(i,blockSize,fileBytes)
    if (i == 0)
        success = compress.BeginCompressBytes(fileBytes,compressedBytes)
    else
        success = compress.MoreCompressBytes(fileBytes,compressedBytes)
    end

    facDest.FileWrite(compressedBytes)

    i = i + 1
end

# At the very end, flush any remaining compressed bytes, if any.
success = compress.EndCompressBytes(compressedBytes)
facDest.FileWrite(compressedBytes)

facSrc.FileClose()
facDest.FileClose()

print "Finished compressing file." + "\n";