com.groupdocs.viewer.options

Class PdfOptimizationOptions

java.lang.Object

com.groupdocs.viewer.options.PdfOptimizationOptions

public class PdfOptimizationOptions
extends Object

Use this class to specify PDF optimization options to apply to the output PDF file.

These optimization options are supported for any input file formats which are supported for export to PDF. For details and code samples, see this page and its children.

Example usage:

 try (Viewer viewer = new Viewer("sample.docx")) {
     PdfViewOptions viewOptions = new PdfViewOptions();
     viewOptions.setPdfOptimizationOptions(new PdfOptimizationOptions());
     viewOptions.getPdfOptimizationOptions().setLinearize(true);
     viewOptions.getPdfOptimizationOptions().setRemoveAnnotations(true);
     viewOptions.getPdfOptimizationOptions().setRemoveFormFields(true);
     viewOptions.getPdfOptimizationOptions().setConvertToGrayScale(true);
     viewOptions.getPdfOptimizationOptions().setSubsetFonts(true);
     viewOptions.getPdfOptimizationOptions().setCompressImages(true);
     viewOptions.getPdfOptimizationOptions().setImageQuality(50);
     viewOptions.getPdfOptimizationOptions().setResizeImages(true);
     viewOptions.getPdfOptimizationOptions().setMaxResolution(50);
     viewOptions.getPdfOptimizationOptions().setRemovePrivateInfo(true);
     viewOptions.getPdfOptimizationOptions().setUnembedFonts(true);
     viewOptions.getPdfOptimizationOptions().setLinkDuplicateStreams(true);
     viewOptions.getPdfOptimizationOptions().setAllowReusePageContent(true);

     viewer.view(viewOptions);
 }
 

See Also:

Viewer, PdfViewOptions

Constructor Summary

Constructors

Constructor and Description
PdfOptimizationOptions() Sets up default values of MaxResolution option to 300 and ImageQuality option to 100.

Method Summary

Modifier and Type	Method and Description
int	getImageQuality() If the source PDF file contains images, consider compressing the images and setting their quality.
int	getMaxResolution() Can be used with CompressImages option to resize the images with a lower resolution.
boolean	isAllowReusePageContent() If this property is set to true, the page content will be reused when optimizing the document for identical pages.
boolean	isCompressImages() If the source PDF file contains images, consider compressing the images and setting their quality.
boolean	isConvertToGrayScale() PDF file is composed of Text, Image, Attachment, Annotations, Graphs and other objects.
boolean	isLinearize() Enables optimization the output PDF file for viewing online with a web browser.
boolean	isLinkDuplicateStreams() Sometimes a document contains several identical resource streams (for example images).
boolean	isOptimizeSpreadsheets() Optimize Excel spreadsheets border lines and fonts for smaller output file size.
boolean	isRemoveAnnotations() Annotations can be deleted when they are unnecessary.
boolean	isRemoveFormFields() If the PDF document contains AcroForms, we can try to reduce the file size by flattening form fields.
boolean	isRemovePrivateInfo() Remove private information (page piece info) if set to true.
boolean	isRemoveUnusedObjects() A PDF document sometimes contains the PDF objects that are not referenced from any other object in the document.
boolean	isRemoveUnusedStreams() Sometimes a document contains unused resource streams.
boolean	isResizeImages() Can be used with CompressImages option to resize the images with a lower resolution.
boolean	isSubsetFonts() Every font used to display text on the page contains set of glyphs for font characters.
boolean	isUnembedFonts() If the document uses embedded fonts it means that all font data is placed in the document.
void	setAllowReusePageContent(boolean allowReusePageContent) Sets whether to allow reusing page content in the PDF.
void	setCompressImages(boolean compressImages) Sets whether to compress the images in the PDF.
void	setConvertToGrayScale(boolean convertToGrayScale) Sets whether to convert the PDF to grayscale.
void	setImageQuality(int imageQuality) Sets the image quality for compressing the images in the PDF.
void	setLinearize(boolean linearize) Sets whether to optimize output PDF for online browsing with a web browser.
void	setLinkDuplicateStreams(boolean linkDuplicateStreams) Sets whether to link duplicate streams in the PDF.
void	setMaxResolution(int maxResolution) Sets the maximum resolution for resizing the images in the PDF.
void	setOptimizeSpreadsheets(boolean optimizeSpreadsheets) Sets whether to optimize the spreadsheets in the PDF.
void	setRemoveAnnotations(boolean removeAnnotations) Sets whether to remove unnecessary annotations from the PDF.
void	setRemoveFormFields(boolean removeFormFields) Sets whether to remove form fields from the PDF.
void	setRemovePrivateInfo(boolean removePrivateInfo) Sets whether to remove private information from the PDF.
void	setRemoveUnusedObjects(boolean removeUnusedObjects) Sets whether to remove unused objects from the PDF.
void	setRemoveUnusedStreams(boolean removeUnusedStreams) Sets whether to remove unused streams from the PDF.
void	setResizeImages(boolean resizeImages) Sets whether to resize the images in the PDF.
void	setSubsetFonts(boolean subsetFonts) Sets whether to subset the fonts in the PDF.
void	setUnembedFonts(boolean unembedFonts) Sets whether to unembed the embedded fonts in the PDF.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PdfOptimizationOptions

public PdfOptimizationOptions()

Sets up default values of MaxResolution option to 300 and ImageQuality option to 100.

For details and code samples, see this page and its children.

Method Detail

getImageQuality

public int getImageQuality()

If the source PDF file contains images, consider compressing the images and setting their quality. In order to enable image compression, set CompressImages option to true. All the images in a document will be re-compressed. The compression is defined by the ImageQuality property, which is the value of the quality in percent. 100% is unchanged quality. To decrease image quality, set the CompressImages option to true and ImageQuality property less than 100.

Note: The default value is 100. To change the image quality, first set the setCompressImages(boolean) property to true. For code example, see this documentation.

Returns:

the image quality (value between 1 and 100).

getMaxResolution

public int getMaxResolution()

Can be used with CompressImages option to resize the images with a lower resolution. In this case, we should set CompressImage to true, ResizeImages to true and MaxResolution to the appropriate value.

Note: The default value is 300. To allow this option, set the setCompressImages(boolean) and setMaxResolution(int) properties to true. For code example, see this documentation.

Returns:

the maximum resolution for the images.

isAllowReusePageContent

public boolean isAllowReusePageContent()

If this property is set to true, the page content will be reused when optimizing the document for identical pages.

Note: The default value is false.

Returns:

true if page content is reused, false otherwise.

isCompressImages

public boolean isCompressImages()

If the source PDF file contains images, consider compressing the images and setting their quality. In order to enable image compression, set this option to true. All the images in a document will be re-compressed. The compression is defined by the ImageQuality property, which is the value of the quality in percent. 100% is unchanged quality. To decrease image quality, set the ImageQuality property less than 100.

Note: The default value is false. Use this option to allow other compressing options: setImageQuality(int) and . For code example, see this documentation.

Returns:

true if images are compressed, false otherwise.

isConvertToGrayScale

public boolean isConvertToGrayScale()

PDF file is composed of Text, Image, Attachment, Annotations, Graphs and other objects. You may come across a requirement to convert a PDF from RGB colorspace to grayscale so that it would be faster while printing those PDF files. Also when the file is converted to grayscale, the size of the document is also reduced but with this change, the quality of the document may drop. Currently, this feature is supported by the Pre-Flight feature of Adobe Acrobat.

Note: The default value is false. For code example, see this documentation.

Returns:

true if the PDF is converted to grayscale, false otherwise.

isLinearize

public boolean isLinearize()

Enables optimization the output PDF file for viewing online with a web browser.

For code example, see this documentation.

Returns:

true if the output PDF is optimized for online browsing, false otherwise.

isLinkDuplicateStreams

public boolean isLinkDuplicateStreams()

Sometimes a document contains several identical resource streams (for example images). This may happen for example when a document is concatenated with itself. The output document contains two independent copies of the same resource stream. We analyze all resource streams and compare them. If streams are duplicated they are merged, that is, only one copy is left, references are changed appropriately and copies of the object are removed. Sometimes this decreases the document size.

Note: The default value is false.

Returns:

true if duplicate streams are linked, false otherwise.

isOptimizeSpreadsheets

public boolean isOptimizeSpreadsheets()

Optimize Excel spreadsheets border lines and fonts for smaller output file size.

The output PDF will not include embedded Arial and Times New Roman fonts with characters 32-127.

Note: The default value is false. For code example, see this documentation.

Returns:

true if spreadsheets are optimized, false otherwise.

isRemoveAnnotations

public boolean isRemoveAnnotations()

Annotations can be deleted when they are unnecessary. When they are needed but do not require additional editing, they can be flattened. It will reduce the file size.

Note: The default value is false. For code example, see this documentation.

Returns:

true if annotations are removed, false otherwise.

isRemoveFormFields

public boolean isRemoveFormFields()

If the PDF document contains AcroForms, we can try to reduce the file size by flattening form fields.

Note: The default value is false. For code example, see this documentation.

Returns:

true if form fields are removed, false otherwise.

isRemovePrivateInfo

public boolean isRemovePrivateInfo()

Remove private information (page piece info) if set to true.

Note: The default value is false.

Returns:

true if private information is removed, false otherwise.

isRemoveUnusedObjects

public boolean isRemoveUnusedObjects()

A PDF document sometimes contains the PDF objects that are not referenced from any other object in the document. This may happen, for example, when a page is removed from the document page tree but the page object itself isn’t removed. Removing these objects doesn’t make the document invalid but rather shrinks it.

Note: The default value is false.

Returns:

true if unused objects are removed, false otherwise.

isRemoveUnusedStreams

public boolean isRemoveUnusedStreams()

Sometimes a document contains unused resource streams. These streams are not “unused objects” because they are referenced from a page’s resource dictionary. This may happen in cases where an image has been removed from the page but not from the page resources. Also, this situation often occurs when pages are extracted from the document and document pages have “common” resources, that is, the same Resources object. Page contents are analyzed in order to determine if a resource stream is used or not. Unused streams are removed. Sometimes this decreases the document size.

Note: The default value is false.

Returns:

true if unused streams are removed, false otherwise.

isResizeImages

public boolean isResizeImages()

Can be used with CompressImages option to resize the images with a lower resolution. In this case, we should set CompressImage to true, ResizeImages to true and MaxResolution to the appropriate value.

Note: The default value is false. To allow this option, set the property to true. This option allows setting the property. For code example, see this documentation.

Returns:

true if images are resized, false otherwise.

isSubsetFonts

public boolean isSubsetFonts()

Every font used to display text on the page contains set of glyphs for font characters. PDF specification supports "font subset" i.e. font with only those glyphs which are used. This may cause issues when text should be updated (since probably required glyphs are absent in the font), but for the document which is not planned to change this allows to decrease size.

Note: The default value is false. If the file uses embedded fonts, it contains all font data. GroupDocs.Viewer can subset embedded fonts to reduce the file size. For code example, see this documentation.

Returns:

true if fonts are subsetted, false otherwise.

isUnembedFonts

public boolean isUnembedFonts()

If the document uses embedded fonts it means that all font data is placed in the document. The advantage is that the document is viewable regardless of whether the font is installed on the user’s machine or not. But embedding fonts makes the document larger. The unembed fonts method removes all embedded fonts. This decreases the document size but the document may become unreadable if the correct font is not installed.

Note: The default value is false.

Returns:

true if embedded fonts are unembedded, false otherwise.

setAllowReusePageContent

public void setAllowReusePageContent(boolean allowReusePageContent)

Sets whether to allow reusing page content in the PDF.

Note: The default value is false.

Parameters:

allowReusePageContent - true to allow reusing page content, false otherwise.

setCompressImages

public void setCompressImages(boolean compressImages)

Sets whether to compress the images in the PDF.

Note: The default value is false. Use this option to allow other compressing options: setImageQuality(int) and . For code example, see this documentation.

Parameters:

compressImages - true to compress the images, false otherwise.

setConvertToGrayScale

public void setConvertToGrayScale(boolean convertToGrayScale)

Sets whether to convert the PDF to grayscale.

Note: The default value is false. For code example, see this documentation.

Parameters:

convertToGrayScale - true to convert the PDF to grayscale, false otherwise.

setImageQuality

public void setImageQuality(int imageQuality)

Sets the image quality for compressing the images in the PDF.

Note: The default value is 100. To change the image quality, first set the setCompressImages(boolean) property to true. For code example, see this documentation.

Parameters:

imageQuality - the image quality (value between 1 and 100).

setLinearize

public void setLinearize(boolean linearize)

Sets whether to optimize output PDF for online browsing with a web browser.

For code example, see this documentation.

Parameters:

linearize - true to optimize the output PDF for online browsing, false otherwise.

setLinkDuplicateStreams

public void setLinkDuplicateStreams(boolean linkDuplicateStreams)

Sets whether to link duplicate streams in the PDF.

Note: The default value is false.

Parameters:

linkDuplicateStreams - true to link duplicate streams, false otherwise.

setMaxResolution

public void setMaxResolution(int maxResolution)

Sets the maximum resolution for resizing the images in the PDF.

Note: The default value is 300. To allow this option, set the setCompressImages(boolean) and setMaxResolution(int) properties to true. For code example, see this documentation.

Parameters:

maxResolution - the maximum resolution for the images.

setOptimizeSpreadsheets

public void setOptimizeSpreadsheets(boolean optimizeSpreadsheets)

Sets whether to optimize the spreadsheets in the PDF.

For code example, see this documentation.

Parameters:

optimizeSpreadsheets - true to optimize the spreadsheets, false otherwise.

setRemoveAnnotations

public void setRemoveAnnotations(boolean removeAnnotations)

Sets whether to remove unnecessary annotations from the PDF.

Note: The default value is false. For code example, see this documentation.

Parameters:

removeAnnotations - true to remove unnecessary annotations, false otherwise.

setRemoveFormFields

public void setRemoveFormFields(boolean removeFormFields)

Sets whether to remove form fields from the PDF.

Note: The default value is false. For code example, see this documentation.

Parameters:

removeFormFields - true to remove form fields, false otherwise.

setRemovePrivateInfo

public void setRemovePrivateInfo(boolean removePrivateInfo)

Sets whether to remove private information from the PDF.

Note: The default value is false.

Parameters:

removePrivateInfo - true to remove private information, false otherwise.

setRemoveUnusedObjects

public void setRemoveUnusedObjects(boolean removeUnusedObjects)

Sets whether to remove unused objects from the PDF.

Note: The default value is false.

Parameters:

removeUnusedObjects - true to remove unused objects, false otherwise.

setRemoveUnusedStreams

public void setRemoveUnusedStreams(boolean removeUnusedStreams)

Sets whether to remove unused streams from the PDF.

Parameters:

removeUnusedStreams - true to remove unused streams, false otherwise.

setResizeImages

public void setResizeImages(boolean resizeImages)

Sets whether to resize the images in the PDF.

Note: The default value is false. To allow this option, set the property to true. This option allows setting the property. For code example, see this documentation.

Parameters:

resizeImages - true to resize the images, false otherwise.

setSubsetFonts

public void setSubsetFonts(boolean subsetFonts)

Sets whether to subset the fonts in the PDF.

Note: The default value is false. If the file uses embedded fonts, it contains all font data. GroupDocs.Viewer can subset embedded fonts to reduce the file size. For code example, see this documentation.

Parameters:

subsetFonts - true to subset the fonts, false otherwise.

setUnembedFonts

public void setUnembedFonts(boolean unembedFonts)

Sets whether to unembed the embedded fonts in the PDF.

Note: The default value is false.

Parameters:

unembedFonts - true to unembed the embedded fonts, false otherwise.