ImageEn, unit iexBitmaps

TIOParams.J2000_SubSamplingV

TIOParams.J2000_SubSamplingV


Declaration

property J2000_SubSamplingV: Integer;


Description

Specifies the vertical subsampling when using YCbCr color space.
Alllowed values: 1 for non subsampling, 2 for double subsampling (halves vertical Cb and Cr channel size).
It is suggested to use YCbCr and at least horizontal subsampling when compressing big images, due to the reduced memory requirements.
Reduction of resulting file size is detectable when lossless compression is used (J2000_Rate = 1).
This property only works when ielib.dll or ievision.dll is present.

Default: 1


Example

// Save a big image as YCbCr with horizontal and vertical subsampling
ImageEnView1.IO.Params.J2000_ColorSpace := ioJ2000_YCbCr;
ImageEnView1.IO.Params.J2000_Rate := 1;
ImageEnView1.IO.Params.J2000_SubSamplingH := 2;
ImageEnView1.IO.Params.J2000_SubSamplingV := 2;
ImageEnView1.IO.SaveToFile('bigimage.jp2');