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rasterImageFormat Property

Summary

Output format to use for raster conversion.

Syntax

TypeScript

JavaScript

Object.defineProperty(DocumentConverterJobData.prototype, 'rasterImageFormat', 
   get: function(), 
   set: function(value) 
)

rasterImageFormat: RasterImageFormat;

Property Value

The output format to use for raster conversion.

Remarks

Jobs can be converted using document or raster formats for the output. To convert to a document format (using LEADTOOLS Document Writer), set DocumentFormat to the desired DocumentFormat value and set RasterImageFormat to RasterImageFormat.Unknown.

To convert to a raster format (using LEADTOOLS Raster Codecs), set RasterImageFormat to the desired RasterImageFormat value and set DocumentFormat to DocumentFormat.User.

Therefore, one of DocumentFormat and RasterImageFormat is used during the conversion, otherwise, an exception will be thrown.

Use RasterImageBitsPerPixel to set the bits/pixel value to use for the output document when using raster conversion.

Optimized TIFF or PDF output:

TIFF and PDF files support different raster compression per page and this can be used to greatly decrease the size of the output file. The user can take advantage of this by using the special values described below.

When RasterImageFormat is either RasterImageFormat.Tif (by default, means uncompressed TIFF) or RasterImageFormat.RasPdf (by default, means uncompressed raster PDF) and RasterImageBitsPerPixel is 0 (the default value), then the converter will deduce that the user wishes to convert to a raster TIFF or PDF with optimized compression depending on the bits per pixel value of the image of each input page.

The values used for PDF are obtained from the current PdfDocumentOptions properties of oneBitImageCompression (default value of jbig2) and coloredImageCompression (default value of jpeg). These values are translated to the equivalent RasterImageFormat value during conversion.

For instance, if the input is a TIFF or PDF file with page 1, a monochrome 1 bit per pixel image, and page 2, a color 24 bits per pixel image, then using the values described above the converter will generate the following:

RasterImageFormat.rasPdf and 0 for rasterImageBitsPerPixel: Page 1 will be compressed using the value set in the oneBitImageCompression property of the PdfDocumentOptions object. If this value is the default of jbig2 for instance, then RasterImageFormat.rasPdfJbig2 will be used. Page 2 will be compressed using the value set in the coloredImageCompression property. If this value is the default of jpeg, then RasterImageFormat.rasPdfJpeg411 will be used.

RasterImageFormat.tif and 0 for rasterImageBitsPerPixel: Page 1 will be compressed using RasterImageFormat.ccittGroup4 and page 2 will be compressed using RasterImageFormat.tifJpeg411.

In either case, set the quality factor value for JPEG compression as usual in CodecsJpegSaveOptions.QualityFactor used by RasterCodecs instance on the service.

Any other value means the user has set the format or bits per pixel to a specific value and the auto-optimization technique will not be used.

Example

For an example, refer to Convert.

Requirements

Target Platforms

Reference

DocumentConverterJobData Class

DocumentConverterJobData Members

Leadtools.Document Namespace

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Help Version 20.0.2020.4.3