Meziantou.FrameworkJpeg2000DecodingOptions Class
Immutable options of the JPEG 2000 decoder (ImageConfiguration.Jpeg2000Decoding): the quality layers it decodes.
public sealed class Jpeg2000DecodingOptionsRemarks
They apply to every operation that decodes the pixels of a JPEG 2000 file: eager loads, sequential readers and collections. Identification reads no pixel and is not affected.
Constructors
| Name | Description |
|---|---|
| Jpeg2000DecodingOptions() |
Jpeg2000DecodingOptions()
public Jpeg2000DecodingOptions()No documentation is available.
Properties
| Name | Description |
|---|---|
| Default | Gets the default options: every quality layer decoded. |
| QualityLayerLimit | Gets the number of quality layers decoded, or null (the default) to decode all of them. |
Default
Jpeg2000DecodingOptions.csGets the default options: every quality layer decoded.
public static Jpeg2000DecodingOptions Default { get; }Property value
QualityLayerLimit
Jpeg2000DecodingOptions.csGets the number of quality layers decoded, or null (the default) to decode all of them.
public int? QualityLayerLimit { get; init; }Property value
Exceptions
ArgumentOutOfRangeException- The value is not positive.
Remarks
A JPEG 2000 codestream holds its coding passes in quality layers: the first layer gives a coarse image, and each layer that follows refines it, up to the full quality of the file. With a limit, the coding passes of the next layers are not decoded: the image is the one a file cut after the last of these layers would give, as opj_decompress -l gives it. A limit at least the number of layers of a tile decodes the whole tile.
The packets of the other layers are still read, so that the decoder finds the packets it needs: the time saved is the one of the coding passes. When the packets come layer by layer (the LRCP progression without progression change), the decoder stops at the last layer it needs.