Locating and Opening Compressors and Decompressors

The following example uses the ICLocate11FA8SY function to find a compressor that can compress an 8-bits-per-pixel bitmap.

BITMAPINFOHEADER bih;

HIC              hIC

// Initialize the bitmap structure.

bih.biSize = sizeof(BITMAPINFOHEADER);

bih.biWidth = bih.biHeight = 0;

bih.biPlanes = 1;

bih.biCompression = BI_RGB;      // standard RGB bitmap

bih.biBitcount = 8;              // 8 bits-per-pixel format

bih.biSizeImage = 0;

bih.biXPelsPerMeter = bih.biYPelsPerMeter = 0;

bih.biClrUsed = bih.biClrImportant = 256;

hIC = ICLocate (ICTYPE_VIDEO, 0L, (LPBITMAPINFOHEADER) &bih,

    NULL, ICMODE_COMPRESS);

The following example enumerates the decompressors in the system to find one that can handle the format of its images. This example uses ICTYPE_VIDEO (which is equivalent to the  VIDC  four-character code) and the ICDecompressQuery8U1GEV macro to determine if a compressor or decompressor supports the image format.

for (i=0; ICInfo(fccType, i, &icinfo); i++)

{ 

    hic = ICOpen(icinfo.fccType, icinfo.fccHandler, ICMODE_QUERY);

    if (hic)

    { 

        // Skip this compressor if it can't handle the format.

        if (fccType == ICTYPE_VIDEO && pvIn != NULL &&

            ICDecompressQuery(hic, pvIn, NULL) != ICERR_OK)

        { 

            ICClose(hic);

            continue;

        }

        // Find out the compressor name.

        ICGetInfo(hic, &icinfo, sizeof(icinfo));

        // Add it to the combo box.

        n = ComboBox_AddString(hwndC,icinfo.szDescription);

        ComboBox_SetItemData(hwndC, n, hic);

    }

}

The following example attempts to locate a specific compressor to compress the 8-bit RGB959Q0EE format to an 8-bit RLE format.

BITMAPINFOHEADER    bihIn, bihOut;

HIC                 hIC

// Initialize the bitmap structure.

biSize = bihOut.biSize = sizeof(BITMAPINFOHEADER);

bihIn.biWidth = bihIn.biHeight = bihOut.biWidth = bihOut.biHeight = 0;

bihIn.biPlanes = bihOut.biPlanes= 1;

bihIn.biCompression = BI_RGB;        // standard RGB bitmap for input

bihOut.biCompression = BI_RLE8;      // 8-bit RLE for output format

bihIn.biBitcount = bihOut.biBitCount = 8;  // 8 bits-per-pixel format

bihIn.biSizeImage = bihOut.biSizeImage = 0;

bihIn.biXPelsPerMeter = bih.biYPelsPerMeter =

    bihOut.biXPelsPerMeter = bihOut.biYPelsPerMeter = 0;

bihIn.biClrUsed = bih.biClrImportant =

    bihOut.biClrUsed = bihOut.biClrImportant = 256;

hIC = ICLocate (ICTYPE_VIDEO, 0L,

    (LPBITMAPINFOHEADER)&bihIn,

    (LPBITMAPINFOHEADER)&bihOut, ICMODE_COMPRESS);