Specifies predefined quality factors that can be used when saving with the LEAD Cmp Bitamp Encoder (CLSID_WICLeadCmpEncoder).
typedef enum WICLeadCmpQualityFactorPredefined{ WICLeadCmpPerfectQuality1 = -1, WICLeadCmpPerfectQuality2 = -2, WICLeadCmpSuperQuality = -3, WICLeadCmpQuality = -4, WICLeadCmpQualityAndSize = -5, WICLeadCmpSharp = -6, WICLeadCmpLessTiling = -7, WICLeadCmpMaximumQuality = -8, WICLeadCmpMaximumCompression = -9, WICLeadCmpCustom = -10, } WICLeadCmpQualityFactorPredefined; |
This enumeration is used with the IWICLeadBitmapEncoder::GetLeadEnumFriendlyName method, and the QualityFactor property bag item.
WICLeadCmpQualityFactorPredefined Meaning WICLeadCmpPerfectQuality1 Perfect quality 1. This option compresses all colors of a 24-bit file and maintains the quality of the original image at a smaller file size. As the name suggests, there is no visual loss of color at this setting. WICLeadCmpPerfectQuality2 Perfect quality 2. This will produce a smaller file size than WICLeadCmpPerfectQuality1 while maintaining similar quality. WICLeadCmpSuperQuality Quality far more important than size. This option removes colors not noticed by the human eye. Most viewers cannot tell the difference between an image compressed at this level and the original image. WICLeadCmpQuality Quality more important than size. While more colors are removed, most of them are colors or shades that are close to one another. The compressed image will appear very much like the original image. It will take some study to see the difference. WICLeadCmpQualityAndSize Quality and size equally important. This option provides the highest compression while maintaining good image quality. Try this option first, then move up or down the list accordingly to obtain acceptable compression size and image quality. WICLeadCmpSharp Size more important that quality (sharp). This option is recommended for images that have sharp edges. For example, an image that has a text overlay or an image with many straight lines. While it creates a larger file than the next option, it retains better edges. WICLeadCmpLessTiling Size more important than quality (less tiling). This option produces less tiling in the image than the previous options. However, it may distort text or straight lines. It is a good option for image database applications. WICLeadCmpMaximumQuality Maximum compression keeping quality. This option provides maximum compression while maintaining image quality as high as possible . WICLeadCmpMaximumCompression Maximum compression. This option gives maximum compression. It is equivalent to a QualityFactor of 255. WICLeadCmpCustom This is not to be used as a QualityFactor. See remarks below.
The values in this enumeration are used when setting the QualityFactor property bag item with the LEAD Cmp Bitmap Encoder.
For more information on setting the QualityFactor, see the QualityFactor property bag item..
LEAD WIC-Enabled Codecs Overview
Registering a LEAD WIC-Enabled Codec
LEAD Bitmap Encoder Property Bag
LEAD Bitmap Encoder Property Bag: JPEG2000 Specific Options
LEAD Bitmap Encoder Property Bag: JBIG2 Specific Options
LEAD Bitmap Encoder Property Bag: XPS Specific Options
For an example refer to the IWICLeadBitmapEncoder::GetQualityFactorPredefined method.