IWICColorTransform::Initialize method

Initializes an IWICColorTransform with a IWICBitmapSource and transforms it from one IWICColorContext to another.

Syntax

C++
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HRESULT Initialize(
  [in] IWICBitmapSource      *pIBitmapSource,
  [in] IWICColorContext      *pIContextSource,
  [in] IWICColorContext      *pIContextDest,
  [in] REFWICPixelFormatGUID pixelFmtDest
);

Parameters

pIBitmapSource [in]

Type: IWICBitmapSource*

The bitmap source used to initialize the color transform.

pIContextSource [in]

Type: IWICColorContext*

The color context source.

pIContextDest [in]

Type: IWICColorContext*

The color context destination.

pixelFmtDest [in]

Type: REFWICPixelFormatGUID

The GUID of the desired pixel format.

This parameter is limited to a subset of the native WIC pixel formats, see Remarks for a list.

Return value

Type: HRESULT

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

The currently supported formats for the pIContextSource and pixelFmtDest parameters are:

  • GUID_WICPixelFormat8bppGray
  • GUID_WICPixelFormat16bppGray
  • GUID_WICPixelFormat16bppBGR555
  • GUID_WICPixelFormat16bppBGR565
  • GUID_WICPixelFormat24bppBGR
  • GUID_WICPixelFormat24bppRGB
  • GUID_WICPixelFormat32bppBGR
  • GUID_WICPixelFormat32bppBGRA
  • GUID_WICPixelFormat32bppPBGRA
  • GUID_WICPixelFormat32bppPRGBA (Windows 8 and later)
  • GUID_WICPixelFormat32bppRGBA
  • GUID_WICPixelFormat32bppBGR101010
  • GUID_WICPixelFormat32bppCMYK
  • GUID_WICPixelFormat48bppBGR
  • GUID_WICPixelFormat64bppBGRA (Windows 8 and later)
  • GUID_WICPixelFormat64bppPBGRA (Windows 8 and later)
  • GUID_WICPixelFormat64bppPRGBA (Windows 8 and later)
  • GUID_WICPixelFormat64bppRGBA (Windows 8 and later)

In order to get correct behavior from a color transform, the input and output pixel formats must be compatible with the source and destination color profiles. For example, an sRGB destination color profile will produce incorrect results when used with a CMYK destination pixel format.

Examples

The following example performs a color transform from one IWICColorContext to another.

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    IWICImagingFactory *pFactory = NULL;
    IWICBitmapDecoder *pDecoder = NULL;
    IWICBitmapFrameDecode *pBitmapFrame = NULL;
    IWICColorContext *pContextSrc = NULL;
    IWICColorContext *pContextDst = NULL;
    IWICColorTransform *pColorTransform = NULL;

    UINT uiFrameCount = 0;

    HRESULT hr = CoCreateInstance(
                    CLSID_WICImagingFactory,
                    NULL, CLSCTX_INPROC_SERVER,
                    IID_IWICImagingFactory,
                    (LPVOID*) &pFactory);

    if (SUCCEEDED(hr))
    {
        hr = pFactory->CreateDecoderFromFilename(
                           L"test.jpg",
                           NULL,
                           GENERIC_READ,
                           WICDecodeMetadataCacheOnDemand,
                           &pDecoder);
    }

    if (SUCCEEDED(hr))
    {
        hr = pDecoder->GetFrameCount(&uiFrameCount);
    }

    if (SUCCEEDED(hr) && (uiFrameCount > 0))
    {
        hr = pDecoder->GetFrame(0, &piBitmapFrame);
    }

    if (SUCCEEDED(hr))
    {
        hr = pFactory->CreateColorContext(&pContextSrc);
    }

    if (SUCCEEDED(hr))
    {
        hr = pContextSrc->InitializeFromFilename(
                              L"c:\\windows\\system32\\spool\\drivers\\color\\kodak_dc.icm");
    }

    if (SUCCEEDED(hr))
    {
        hr = pFactory->CreateColorContext(&pContextDst);
    }

    if (SUCCEEDED(hr))
    {
        hr = pContextDst->InitializeFromFilename(
                              L"c:\\windows\\system32\\spool\\drivers\\color\\sRGB Color Space Profile.icm");
    }

    hr = E_FAIL;

    if (SUCCEEDED(hr))
    {
        // Transform from src icm to the destination icm. 
        hr = pColorTransform->Initialize( pBitmapFrame,
                                          pContextSrc,
                                          pContextDst,
                                          GUID_WICPixelFormat32bppBGRA);
    }

    if (SUCCEEDED(hr))
    {
        UINT uiWidth = 0, uiHeight = 0;
        UINT cbStride = 0;
        UINT cbBufferSize = 0;
        BYTE *pbBuffer = NULL; 

        hr = pColorTransform->GetSize(&uiWidth, &uiHeight);

        if (SUCCEEDED(hr))
        {
            WICRect rc = { 0 };
            rc.X = 0;
            rc.Y = 0;
            rc.Width = uiWidth;
            rc.Height = 1; // scanline

            for (UINT i = 0; SUCCEEDED(hr) && (i < uiHeight); i++)
            {
                hr = pColorTransform->CopyPixels(&rc, cbStride, cbBufferSize - (rc.Y * cbStride), pbBuffer);
                pbBuffer += cbStride;
                rc.Y += 1;
            }
        }
    }

    if (pFactory)
    {
        pFactory->Release();
    }

    if (pDecoder)
    {
        pDecoder->Release();
    }

    if (pBitmapFrame)
    {
        pBitmapFrame->Release();
    }

    if (pContextSrc)
    {
        pContextSrc->Release();
    }

    if (pContextDst)
    {
        pContextDst->Release();
    }

    if (pColorTransform)
    {
        pColorTransform->Release();
    }

    return hr;

Requirements

Minimum supported client

Windows XP with SP2, Windows Vista [desktop apps | Windows Store apps]

Minimum supported server

Windows Server 2008 [desktop apps | Windows Store apps]

Header
Wincodec.h

IDL
Wincodec.idl

Library
Windowscodecs.lib

DLL
Windowscodecs.dll

 

 

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