'Declaration
 
<BrowsableAttribute(False)>
<DefaultValueAttribute()>
<DescriptionAttribute("Specifies the luminance quality setting for saving JPEG files.")>
<DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Hidden)>
Public Property Luminance As Integer

'Usage
 
Dim instance As SaveOptionsJpeg
Dim value As Integer
 
instance.Luminance = value
 
value = instance.Luminance

[BrowsableAttribute(false)]
[DefaultValueAttribute()]
[DescriptionAttribute("Specifies the luminance quality setting for saving JPEG files.")]
[DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Hidden)]
public int Luminance {get; set;}

[BrowsableAttribute(false)]
[DefaultValueAttribute()]
[DescriptionAttribute("Specifies the luminance quality setting for saving JPEG files.")]
[DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Hidden)]
public: __property int get_Luminance();
public: __property void set_Luminance( 
   int value
);

[BrowsableAttribute(false)]
[DefaultValueAttribute()]
[DescriptionAttribute("Specifies the luminance quality setting for saving JPEG files.")]
[DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Hidden)]
public:
property int Luminance {
   int get();
   void set (    int value);
}

Property Value

The default value is 10. It should be within the range of 0 to 255.

JPEG and ePIC images are stored in a compressed format. Compression is lossy which means when you save a JPEG or ePIC file, there will be data loss. Data loss is the result of JPEG and ePICs ability to achieve high compression ratios. Higher quality settings result in less compression, while lower quality settings result in higher compression. Quality versus compression is a tradeoff.

The image compression ratio can be adjusted by setting the Luminance and Chrominance properties. The Luminance property adjusts the luminance or gray scale quality and the Chrominance property adjusts the chrominance or color quality. Lower settings for these properties result in higher quality images with less compression. Higher settings for these properties result in lower quality images with more compression.

For general use photographic type images, setting Luminance = 24 and Chrominance = 30 provides about a 12:1 image compression ratio with minimal data loss. Compression ratios and perceived image quality will vary depending on the image.

Reference