PdfLZWDecodeFilter Class

Namespace:
GemBox.Pdf.Filters
Assembly:
GemBox.Pdf.dll

The LZWDecode filter decode data that has been encoded using the LZW (Lempel-Ziv-Welch) variable-length, adaptive compression method that has been adopted as one of the standard compression methods in the Tag Image File Format (TIFF) standard. For details on LZW encoding see 7.4.4.2, "Details of LZW Encoding."

public sealed class PdfLZWDecodeFilter : PdfFilter
Public NotInheritable Class PdfLZWDecodeFilter
    Inherits PdfFilter
Inheritance:
System.Object
PdfLZWDecodeFilter

Properties

BitsPerComponent

(May be used only if Predictor is greater than 1) The number of bits used to represent each color component in a sample. Valid values are 1, 2, 4, 8, and (PDF 1.5) 16.

Default value: 8.

public int BitsPerComponent { get; set; }
Public Property BitsPerComponent As Integer
Property Value
System.Int32

The number of bits used to represent each color component in a sample.

Exceptions
System.ArgumentOutOfRangeException

value

System.InvalidOperationException
System.ArgumentOutOfRangeException

Value is not 1, 2, 4, 8 or 16.

System.InvalidOperationException

Predictor is not greater than 1.

InvalidPdfDictionaryEntryException

Value is not according to PDF Specification ISO 32000-1:2008.

See Also

Colors

(May be used only if Predictor is greater than 1) The number of interleaved color components per sample. Valid values are 1 to 4 (PDF 1.0) and 1 or greater (PDF 1.3).

Default value: 1.

public int Colors { get; set; }
Public Property Colors As Integer
Property Value
System.Int32

The number of interleaved color components per sample.

Exceptions
System.ArgumentOutOfRangeException

value

System.InvalidOperationException
System.ArgumentOutOfRangeException

Value is less than 1.

System.InvalidOperationException

Predictor is not greater than 1.

InvalidPdfDictionaryEntryException

Value is not according to PDF Specification ISO 32000-1:2008.

See Also

Columns

(May be used only if Predictor is greater than 1) The number of samples in each row.

Default value: 1.

public int Columns { get; set; }
Public Property Columns As Integer
Property Value
System.Int32

The number of samples in each row.

Exceptions
System.ArgumentOutOfRangeException

value

System.InvalidOperationException
System.ArgumentOutOfRangeException

Value is less than 1.

System.InvalidOperationException

Predictor is not greater than 1.

InvalidPdfDictionaryEntryException

Value is not according to PDF Specification ISO 32000-1:2008.

See Also

EarlyChange

An indication of when to increase the code length. If the value is false, code length increases shall be postponed as long as possible. If the value is true, code length increases shall occur one code early. This parameter is included because LZW sample code distributed by some vendors increases the code length one code earlier than necessary.

Default value: true.

public bool EarlyChange { get; set; }
Public Property EarlyChange As Boolean
Property Value
System.Boolean

The indication of when to increase the code length.

Exceptions
InvalidPdfDictionaryEntryException

Value is not according to PDF Specification ISO 32000-1:2008.

See Also

FilterType

Gets the LZWDecode value.

public override PdfFilterType FilterType { get; }
Public Overrides ReadOnly Property FilterType As PdfFilterType
Property Value
PdfFilterType

The LZWDecode value.

Overrides

Predictor

A code that selects the predictor algorithm, if any. If the value is 1, the PdfFlateDecodeFilter shall assume that the normal algorithm was used to encode the data, without prediction. If the value is greater than 1, the PdfFlateDecodeFilter shall assume that the data was differenced before being encoded, and Predictor selects the predictor algorithm. For more information regarding Predictor values greater than 1, see 7.4.4.4, "LZW and Flate Predictor Functions".

Default value: 1.

public int Predictor { get; set; }
Public Property Predictor As Integer
Property Value
System.Int32

The code that selects the predictor algorithm, if any.

Exceptions
System.ArgumentOutOfRangeException

Value is less than 1.

InvalidPdfDictionaryEntryException

Value is not according to PDF Specification ISO 32000-1:2008.

See Also

PredictorFunction

Gets or sets the predictor algorithm.

Default value: None.

public PdfPredictorFunction PredictorFunction { get; set; }
Public Property PredictorFunction As PdfPredictorFunction
Property Value
PdfPredictorFunction

The predictor algorithm.

Exceptions
InvalidPdfDictionaryEntryException
See Also

Inherited Methods

Equals(System.Object)

Determines whether the specified System.Object is equal to this PdfFilter instance.

(Inherited from PdfFilter)

GetHashCode()

Returns a hash code for this PdfFilter instance.

(Inherited from PdfFilter)

ToString()

Returns a System.String that represents this PdfFilter instance.

(Inherited from PdfFilter)

See Also