(AutoIt) Compress Large Binary File in Blocks

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

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

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

$oFacSrc = ObjCreate("Chilkat_9_5_0.FileAccess")
$oFacDest = ObjCreate("Chilkat_9_5_0.FileAccess")

; Open a large binary file for reading.
Local $bSuccess = $oFacSrc.OpenForRead("qa_data/bmp/big.bmp")
If ($bSuccess <> True) Then
    ConsoleWrite($oFacSrc.LastErrorText & @CRLF)
    Exit
EndIf

; If we compress in 64K chunks, find out how many blocks there will be.
Local $iBlockSize = 65536
Local $iNumBlocks = $oFacSrc.GetNumBlocks($iBlockSize)

; Open an output file for the compressed data.
$bSuccess = $oFacDest.OpenForWrite("qa_data/bmp/compressedBmp.dat")
If ($bSuccess <> True) Then
    ConsoleWrite($oFacDest.LastErrorText & @CRLF)
    Exit
EndIf

$oCompress = ObjCreate("Chilkat_9_5_0.Compression")
$oCompress.Algorithm = "deflate"

Local $oFileBytes
Local $oCompressedBytes

Local $i = 0
While $i < $iNumBlocks
    $oFileBytes = $oFacSrc.ReadBlock($i,$iBlockSize)
    If ($i = 0) Then
        $oCompressedBytes = $oCompress.BeginCompressBytes($oFileBytes)
    Else
        $oCompressedBytes = $oCompress.MoreCompressBytes($oFileBytes)
    EndIf

    $oFacDest.FileWrite($oCompressedBytes)

    $i = $i + 1
Wend

; At the very end, flush any remaining compressed bytes, if any.
$oCompressedBytes = $oCompress.EndCompressBytes()
$oFacDest.FileWrite($oCompressedBytes)

$oFacSrc.FileClose 
$oFacDest.FileClose 

ConsoleWrite("Finished compressing file." & @CRLF)