IG_IP_thumbnail_create

This function creates a resized copy of the image. It can be used for creating a thumbnail (small preview version of the image).

Declaration:

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AT_ERRCOUNT ACCUAPI IG_IP_thumbnail_create_ex( HIGEAR hOriginalImage, LPHIGEAR lphNewThumbnail, AT_DIMENSION nNewWidth, AT_DIMENSION nNewHeight, AT_MODE nInterpMethod, DWORD dwFlags, INT nValue );

Arguments:

Name	Type	Description
hOriginalImage	HIGEAR	HIGEAR handle of image of which to create thumbnail image.
lphNewThumbnail	LPHIGEAR	Pointer to a variable of type HIGEAR to receive the HIGEAR handle of the created thumbnail image.
nNewWidth	AT_DIMENSION	Specifies width wanted for the new image.
nNewHeight	AT_DIMENSION	Specifies height wanted for the new image.
nInterpMethod	AT_MODE	Specifies interpolation method to use for image resizing. See enumIGInterpolations for possible values.
dwFlags	DWORD	The contents of this parameter depends upon the value of nInterpMethod. This is currently not used.
nValue	INT	The contents of this parameter depends upon the value of nInterpMethod: IG_INTERPOLATION_GRAYSCALE - nValue can be from 0 to 100. It takes the proportion of pixels from entry 1 to entry 0 (white/black). IG_INTERPOLATION_PRESERVE_WHITE - nValue can be from 0 to 100. It indicates the threshold value of the amount of white color to include. IG_INTERPOLATION_PRESERVE_BLACK - nValue can be from 0 to 100. It indicates the threshold value of the amount of black color to include. Any other values - nValue is ignored.

Return Value:

Returns 0 if successful. Otherwise, returns the number of ImageGear errors that occurred during this function call.

Supported Raster Image Formats:

If nInterpMethod is IG_INTERPOLATION_GRAYSCALE, IG_INTERPOLATION_PRESERVE_WHITE, or IG_INTERPOLATION_PRESERVE_BLACK:

Indexed RGB - 1 bpp;
Grayscale - 1 bpp.

If nInterpMethod is IG_INTERPOLATION_AVERAGE or IG_INTERPOLATION_BILINEAR:

All pixel formats supported by ImageGear for C and C++, except:

Indexed RGB with non-grayscale palette.

If nInterpMethod is IG_INTERPOLATION_BICUBIC:

All pixel formats supported by ImageGear for C and C++, except:

Indexed RGB with non-grayscale palette.
Grayscale - 1 bpp.

Otherwise, all pixel formats supported by ImageGear for C and C++.

Example:

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HIGEAR hIGear; // HIGEAR handle of the image HIGEAR hIGearThumb; // HIGEAR handle of the thumbnail image AT_ERRCOUNT nErrcount; // Count of errs on stack upon ret from func // Load image file "picture.tif", 1 bpp, from working directory nErrcount = IG_load_file("picture.tif", &hIGear); if(nErrcount == 0) { nErrcount = IG_IP_thumbnail_create_ex(hIGear, &hIGearThumb, 64, 64, IG_INTERPOLATION_GRAYSCALE, 0, 50); if(nErrcount == 0) { // ... // Destroy the thumbnail image IG_image_delete(hIGearThumb); } // Destroy the image IG_image_delete(hIGear); }

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HIGEAR hIGear;            // HIGEAR handle of the image
HIGEAR hIGearThumb;        // HIGEAR handle of the thumbnail image
AT_ERRCOUNT nErrcount;    // Count of errs on stack upon ret from func

// Load image file "picture.tif", 1 bpp, from working directory
nErrcount = IG_load_file("picture.tif", &hIGear);
if(nErrcount == 0)
{
    nErrcount = IG_IP_thumbnail_create_ex(hIGear, &hIGearThumb, 64, 64, IG_INTERPOLATION_GRAYSCALE, 0, 50);
    if(nErrcount == 0)
    {
        // ...
        // Destroy the thumbnail image
        IG_image_delete(hIGearThumb);
    }
    // Destroy the image
    IG_image_delete(hIGear);
}

Remarks:

This function works in the same way as IG_IP_resize_ex with the only difference that it returns a resized copy of the original image, instead of changing the original image. See IG_IP_resize_ex for additional details.