StartCompress(Int32,Int32,Int32,RasterByteOrder,RasterViewPerspective,Int32,IntPtr,Int32,CodecsCompression,CodecsCompressDataCallback) Method

public void StartCompress( 
   int width,
   int height,
   int bitsPerPixel,
   RasterByteOrder order,
   RasterViewPerspective viewPerspective,
   int inputDataLength,
   IntPtr outputData,
   int outputDataLength,
   CodecsCompression compression,
   CodecsCompressDataCallback callback
)

'Declaration
 
Public Overloads Sub StartCompress( _
   ByVal width As Integer, _
   ByVal height As Integer, _
   ByVal bitsPerPixel As Integer, _
   ByVal order As RasterByteOrder, _
   ByVal viewPerspective As RasterViewPerspective, _
   ByVal inputDataLength As Integer, _
   ByVal outputData As IntPtr, _
   ByVal outputDataLength As Integer, _
   ByVal compression As CodecsCompression, _
   ByVal callback As CodecsCompressDataCallback _
) 

'Usage
 
Dim instance As RasterCodecs
Dim width As Integer
Dim height As Integer
Dim bitsPerPixel As Integer
Dim order As RasterByteOrder
Dim viewPerspective As RasterViewPerspective
Dim inputDataLength As Integer
Dim outputData As IntPtr
Dim outputDataLength As Integer
Dim compression As CodecsCompression
Dim callback As CodecsCompressDataCallback
 
instance.StartCompress(width, height, bitsPerPixel, order, viewPerspective, inputDataLength, outputData, outputDataLength, compression, callback)

public void StartCompress( 
   int width,
   int height,
   int bitsPerPixel,
   RasterByteOrder order,
   RasterViewPerspective viewPerspective,
   int inputDataLength,
   IntPtr outputData,
   int outputDataLength,
   CodecsCompression compression,
   CodecsCompressDataCallback callback
)

 function Leadtools.Codecs.RasterCodecs.StartCompress(Int32,Int32,Int32,RasterByteOrder,RasterViewPerspective,Int32,IntPtr,Int32,CodecsCompression,CodecsCompressDataCallback)( 
   width ,
   height ,
   bitsPerPixel ,
   order ,
   viewPerspective ,
   inputDataLength ,
   outputData ,
   outputDataLength ,
   compression ,
   callback 
)

public:
void StartCompress( 
   int width,
   int height,
   int bitsPerPixel,
   RasterByteOrder order,
   RasterViewPerspective viewPerspective,
   int inputDataLength,
   IntPtr outputData,
   int outputDataLength,
   CodecsCompression compression,
   CodecsCompressDataCallback^ callback
) 

Parameters

width

The image being compressed width in pixels.

height

The image being compressed height in pixels.

bitsPerPixel

The image being compressed bits/pixel value.

order

The image being compressed byte order.

viewPerspective

The image being compressed view perspective value.

inputDataLength

Size in bytes of the input image data.

outputData

Pointer to unmanaged memory buffer will be filled with the compressed data.

outputDataLength

Size of outputData in bytes.

compression

Type of compression to use. Valid values are:

Value	Meaning
CodecsCompression.Cmp	LEAD CMP compression format
CodecsCompression.Jpeg444	JPEG File Interchange Format using YUV 4:4:4 color spacing
CodecsCompression.Jpeg422	JPEG File Interchange Format using YUV 4:2:2 color spacing
CodecsCompression.Jpeg411	JPEG File Interchange Format using YUV 4:1:1 color spacing
CodecsCompression.TifJpeg444	JPEG JTIF using YUV 4:4:4 color spacing
CodecsCompression.TifJpeg422	JPEG JTIF using YUV 4:2:2 color spacing
CodecsCompression.TifJpeg411	JPEG JTIF using YUV 4:1:1 color spacing
CodecsCompression.Lead0	LEAD 1 bit, lossless compression
CodecsCompression.Lead1	LEAD 1 bit, excellent compression
CodecsCompression.TiffCcitt	TIFF CCITT
CodecsCompression.TiffCcittG3Fax1Dim	CCITT Group 3 one dimensional
CodecsCompression.TiffCcittG3Fax2Dim	CCITT Group 3 two dimensional
CodecsCompression.TiffCcittG4Fax	CCITT Group 4 two dimensional

callback

The callback method responsible for writing or handling the compressed data.

This method initializes the buffered compression engine. The compression is then carried out using the Compress(Byte[],Int32) method. It is ended by the StopCompress method.

If order is set to to RasterByteOrder.Bgr and viewPerspective is RasterViewPerspective.TopLeft then the data that you put into the input buffer must be RasterByteOrder.Bgr and loaded from top left.

The compression process starts after the first call to Compress(Byte[],Int32). The callback is called when the output buffer is filled with compressed data or after completing the compression process. callback is responsible for emptying the output buffer - storing it, sending it, or doing other processing.

The following is a flow chart that shows the relationship of these methods:

Call StopCompress to end the compression process started by a call to StartCompress(Int32,Int32,Int32,RasterByteOrder,RasterViewPerspective,Int32,Byte[],Int32,Int32,CodecsCompression,CodecsCompressDataCallback).

The quality factor of the compressed data is obtained as follows:

This method does not support signed data images.

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

RasterCodecs Class
RasterCodecs Members
Overload List
Compressing and Decompressing Buffers
Speeding Up 1-Bit Documents