(Ruby) Decompress Large Binary File in Blocks

Decompresses a large binary file in blocks. This example uses BeginDecompressBytes, MoreDecompressBytes, and EndDecompressBytes.

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

require 'chilkat'

# This example requires 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 previously compressed file for decompressing.
# See Compress Large File in Blocks

success = facSrc.OpenForRead("qa_data/bmp/compressedBmp.dat")
if (success != true)
    print facSrc.lastErrorText() + "\n";
    exit
end

# If we compress in 32K chunks, find out how many blocks there will be.
blockSize = 32768
numBlocks = facSrc.GetNumBlocks(blockSize)

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

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

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

i = 0
while i < numBlocks
    success = facSrc.ReadBlock(i,blockSize,compressedBytes)
    if (i == 0)
        success = compress.BeginDecompressBytes(compressedBytes,decompressedBytes)
    else
        success = compress.MoreDecompressBytes(compressedBytes,decompressedBytes)
    end

    facDest.FileWrite(decompressedBytes)

    i = i + 1
end

# At the very end, flush any remaining decompressed bytes, if any.
success = compress.EndDecompressBytes(decompressedBytes)
facDest.FileWrite(decompressedBytes)

facSrc.FileClose()
facDest.FileClose()

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