(C++) Compress and Decompress Base64

Imagine we have data represented as a base64 string. This example demonstrates how to decode, compress, and re-encode to smaller base64 representing the compressed data.

Note: This example requires Chilkat v9.5.0.66 or greater.

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#include <CkCompression.h>
#include <CkBinData.h>

void ChilkatSample(void)
    {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    bool success;

    const char *strBase64 = "VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NClRoZSBxdWljayBicm93biBmb3gganVtcGVkIG92ZXIgdGhlIGxhenkgZG9nLg0KVGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NCg0K";

    CkCompression compress;
    compress.put_Algorithm("deflate");

    CkBinData binDat;
    // Load the base64 data into a BinData object.
    // This decodes the base64. The decoded bytes will be contained in the BinData.
    binDat.AppendEncoded(strBase64,"base64");

    // Compress the BinData.
    compress.CompressBd(binDat);

    // Get the compressed data in base64 format:
    const char *compressedBase64 = binDat.getEncoded("base64");
    std::cout << "compressed base64:" << "\r\n";
    std::cout << compressedBase64 << "\r\n";

    // The compressed base64 is: C8lIVSgszUzOVkgqyi/PU0jLr1DIKs0tSE1RyC9LLVIoAcrnJFZVKqTkp+vxcoUMYeW8XAA=

    // Now decompress:
    binDat.Clear();
    binDat.AppendEncoded(compressedBase64,"base64");
    compress.DecompressBd(binDat);

    const char *decompressedBase64 = binDat.getEncoded("base64");
    std::cout << "decompressed base64:" << "\r\n";
    std::cout << decompressedBase64 << "\r\n";

    // The output is the original data:
    // VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NClRoZSBxdWljayBicm93biBmb3gganVtcGVkIG92ZXIgdGhlIGxhenkgZG9nLg0KVGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NCg0K
    }