PureBasic

Decode Base64 Image String (GIF, JPG, etc.) and Save to File

I have an XML response that includes a base 64 encoded image string (UPS label). It's a huge string and I need to save it as a gif file on my users pc.

This example shows how to do it..

PureBasic

IncludeFile "CkBinData.pb"
IncludeFile "CkXml.pb"

Procedure ChilkatExample()

    success.i = 0

    bd.i = CkBinData::ckCreate()
    If bd.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; I created an extra-small GIF image for this example..
    success = CkBinData::ckLoadFile(bd,"qa_data/gif/xsmall.gif")
    If success <> 1
        Debug "Failed to load GIF image file."
        CkBinData::ckDispose(bd)
        ProcedureReturn
    EndIf

    ; Show GIF bytes as base64:
    Debug CkBinData::ckGetEncoded(bd,"base64")

    ; This particular GIF in base64 is this:
    ; R0lGODlhBQAFAMQAAAAAAP////z8/PHx8evr6+jo6OHh4d7e3sPDw8LCwpqamo2NjWxsbGRkZFpaWk1NTUtLS0hISCwsLCQkJP///wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAEAABQALAAAAAAFAAUAAAUTYCAYQUBAU1lI0TIgztE8jFImIQA7

    ; Let's begin with an XML string:
    x.s = "<abc><def>R0lGODlhBQAFAMQAAAAAAP////z8/PHx8evr6+jo6OHh4d7e3sPDw8LCwpqamo2NjWxsbGRkZFpaWk1NTUtLS0hISCwsLCQkJP///wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAEAABQALAAAAAAFAAUAAAUTYCAYQUBAU1lI0TIgztE8jFImIQA7</def></abc>"

    xml.i = CkXml::ckCreate()
    If xml.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkXml::ckLoadXml(xml,x)

    ; Get the base64 string:
    gifBase64.s = CkXml::ckGetChildContent(xml,"def")

    Debug gifBase64

    ; Load bd with the base64 decoded bytes.  
    CkBinData::ckClear(bd)
    CkBinData::ckAppendEncoded(bd,gifBase64,"base64")

    ; Save to a GIF file.
    success = CkBinData::ckWriteFile(bd,"qa_output/xsmall.gif")


    CkBinData::ckDispose(bd)
    CkXml::ckDispose(xml)


    ProcedureReturn
EndProcedure