PdfCCITTFaxDecodeFilter Class
The CCITTFaxDecode filter decodes image data that has been encoded using either Group 3 or Group 4 CCITT facsimile(fax) encoding.
public sealed class PdfCCITTFaxDecodeFilter : PdfFilterPublic NotInheritable Class PdfCCITTFaxDecodeFilter
Inherits PdfFilter- Inheritance:
- System.ObjectPdfCCITTFaxDecodeFilter
Properties
BlackIs1
A flag indicating whether 1 bits shall be interpreted as black pixels and 0 bits as white pixels, the reverse of the normal PDF convention for image data.
Default value: false.
Property Value
- System.Boolean
The flag indicating whether 1 bits shall be interpreted as black pixels and 0 bits as white pixels, the reverse of the normal PDF convention for image data.
Exceptions
Value is not according to PDF Specification ISO 32000-1:2008.
See Also
Columns
The width of the image in pixels. If the value is not a multiple of 8, the filter shall adjust the width of the unencoded image to the next multiple of 8 so that each line starts on a byte boundary.
Default value: 1728.
Property Value
- System.Int32
The width of the image in pixels.
Exceptions
- System.ArgumentOutOfRangeException
Value is less than 1.
Value is not according to PDF Specification ISO 32000-1:2008.
See Also
DamagedRowsBeforeError
The number of damaged rows of data that shall be tolerated before an error occurs. This entry shall apply only if EndOfLine is true and K is non-negative. Tolerating a damaged row shall mean locating its end in the encoded data by searching for an EndOfLine pattern and then substituting decoded data from the previous row if the previous row was not damaged, or a white scan line if the previous row was also damaged.
Default value: 0.
public int DamagedRowsBeforeError { get; set; }Public Property DamagedRowsBeforeError As IntegerProperty Value
- System.Int32
The number of damaged rows of data that shall be tolerated before an error occurs.
Exceptions
- System.ArgumentOutOfRangeException
Value is less than zero.
Value is not according to PDF Specification ISO 32000-1:2008.
See Also
EncodedByteAlign
A flag indicating whether the filter shall expect extra 0 bits before each encoded line so that the line begins on a byte boundary. If true, the filter shall skip over encoded bits to begin decoding each line at a byte boundary. If false, the filter shall not expect extra bits in the encoded representation.
Default value: false.
Property Value
- System.Boolean
The flag indicating whether the filter shall expect extra 0 bits before each encoded line so that the line begins on a byte boundary.
Exceptions
Value is not according to PDF Specification ISO 32000-1:2008.
See Also
EndOfBlock
A flag indicating whether the filter shall expect the encoded data to be terminated by an end-of-block pattern, overriding the Rows parameter. If false, the filter shall stop when it has decoded the number of lines indicated by Rows or when its data has been exhausted, whichever occurs first. The end-of-block pattern shall be the CCITT end-of-facsimile-block (EOFB) or return-to-control (RTC) appropriate for the K parameter.
Default value: true.
Property Value
- System.Boolean
The flag indicating whether the filter shall expect the encoded data to be terminated by an end-of-block pattern, overriding the Rows parameter.
Exceptions
Value is not according to PDF Specification ISO 32000-1:2008.
See Also
EndOfLine
A flag indicating whether end-of-line bit patterns shall be present in the encoding. The PdfCCITTFaxDecodeFilter shall always accept end-of-line bit patterns. If EndOfLine is true end-of-line bit patterns shall be present.
Default value: false.
Property Value
- System.Boolean
The flag indicating whether end-of-line bit patterns shall be present in the encoding.
Exceptions
Value is not according to PDF Specification ISO 32000-1:2008.
See Also
FilterType
Gets the CCITTFaxDecode value.
public override PdfFilterType FilterType { get; }Public Overrides ReadOnly Property FilterType As PdfFilterTypeProperty Value
The CCITTFaxDecode value.
Overrides
K
A code identifying the encoding scheme used:
- <0Pure two-dimensional encoding (Group 4)
- =0Pure one-dimensional encoding (Group 3, 1-D)
- >0Mixed one- and two-dimensional encoding (Group 3, 2-D), in which a line encoded one-dimensionally may be followed by at most K − 1 lines encoded two-dimensionally
The filter shall distinguish among negative, zero, and positive values of K to determine how to interpret the encoded data; however, it shall not distinguish between different positive K values.
Default value: 0.
Property Value
- System.Int32
The code identifying the encoding scheme used.
Exceptions
Value is not according to PDF Specification ISO 32000-1:2008.
See Also
Rows
The height of the image in scan lines. If the value is 0, the image’s height is not predetermined, and the encoded data shall be terminated by an end-of-block bit pattern or by the end of the filter’s data.
Default value: 0.
Property Value
- System.Int32
The height of the image in scan lines.
Exceptions
- System.ArgumentOutOfRangeException
Value is less than zero.
Value is not according to PDF Specification ISO 32000-1:2008.
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) |