AutoIt Requires Chilkat v11.0.0+

Decompress Large Binary File in Blocks

See more Compression Examples

Decompresses a large binary file in blocks. AutoIt

Local $bSuccess = False

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

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

;  Open a previously compressed file for decompressing.
;  See Compress Large File in Blocks

$bSuccess = $oFacSrc.OpenForRead("c:/temp/qa_output/compressedBmp.dat")
If ($bSuccess = False) Then
    ConsoleWrite($oFacSrc.LastErrorText & @CRLF)
    Exit
EndIf

;  If we compress in 32K chunks, find out how many blocks there will be.
Local $iBlockSize = 32768
Local $iNumBlocks = $oFacSrc.GetNumBlocks($iBlockSize)

;  Open an output file for the decompressed data.
$bSuccess = $oFacDest.OpenForWrite("c:/temp/qa_output/decompressed.bmp")
If ($bSuccess = False) Then
    ConsoleWrite($oFacDest.LastErrorText & @CRLF)
    Exit
EndIf

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

Local $oDecompressedBytes
Local $oCompressedBytes

;  Assuming numBlocks > 1
$oCompress.FirstChunk = True
$oCompress.LastChunk = False

Local $i = 0
While $i < $iNumBlocks
    $oCompressedBytes = $oFacSrc.ReadBlock($i,$iBlockSize)

    $oDecompressedBytes = $oCompress.DecompressBytes($oCompressedBytes)
    $oFacDest.FileWrite($oDecompressedBytes)

    $i = $i + 1

    $oCompress.FirstChunk = False
    If ($i = ($iNumBlocks - 1)) Then
        $oCompress.LastChunk = True
    EndIf

Wend

$oFacSrc.FileClose 
$oFacDest.FileClose 

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