Sample Kotlin code for using Apryse SDK to reduce PDF file size by removing redundant information and compressing data streams using the latest in image compression technology. Learn more about our Kotlin PDF Library.
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//--------------------------------------------------------------------------------------- // Copyright (c) 2001-2019 by PDFTron Systems Inc. All Rights Reserved. // Consult legal.txt regarding legal and license information. //--------------------------------------------------------------------------------------- package com.pdftron.android.pdfnetsdksamples.samples import com.pdftron.android.pdfnetsdksamples.OutputListener import com.pdftron.android.pdfnetsdksamples.PDFNetSample import com.pdftron.android.pdfnetsdksamples.R import com.pdftron.android.pdfnetsdksamples.util.Utils import com.pdftron.pdf.Flattener import com.pdftron.pdf.Optimizer import com.pdftron.pdf.PDFDoc import com.pdftron.pdf.ViewerOptimizedOptions import com.pdftron.sdf.SDFDoc import java.util.ArrayList /** * The following sample illustrates how to reduce PDF file size using 'com.pdftron.pdf.Optimizer' class. * The sample also shows how to simplify and optimize PDF documents for viewing on mobile devices * and on the Web using 'com.pdftron.pdf.Flattener'. * * * * Note: Both 'Optimizer' and 'Flattener' are separately licensable add-on options to the core * PDFNet license. * * * * 'com.pdftron.pdf.Optimizer' can be used to optimize PDF documents by reducing the file size, removing * redundant information, and compressing data streams using the latest in image compression * technology. * * * PDF Optimizer can compress and shrink PDF file size with the following operations: * * * Remove duplicated fonts, images, ICC profiles, and any other data stream. * * Optionally convert high-quality or print-ready PDF files to small, efficient and web-ready PDF. * * Optionally down-sample large images to a given resolution. * * Optionally compress or recompress PDF images using JBIG2 and JPEG2000 compression formats. * * Compress uncompressed streams and remove unused PDF objects. * * * * * 'com.pdftron.pdf.Flattener' can be used to speed-up PDF rendering on mobile devices and on the Web by * simplifying page content (e.g. flattening complex graphics into images) while maintaining vector * text whenever possible. * * * * Flattener can also be used to simplify process of writing custom converters from PDF to other * formats. In this case, Flattener can be used as first step in the conversion pipeline to reduce * any PDF to a very simple representation (e.g. vector text on top of a background image). */ class OptimizerTest : PDFNetSample() init setTitle(R.string.sample_optimizer_title) setDescription(R.string.sample_optimizer_description) // The standard library does not include the Optimizer and Flattener features. // If using the full library, please comment out the following call to enable the sample. // DisableRun(); > override fun run(outputListener: OutputListener?) super.run(outputListener) mOutputListener = outputListener mFileList.clear() printHeader(outputListener!!) val input_filename = "newsletter.pdf" val input_filename2 = "newsletter_opt1.pdf" val input_filename3 = "newsletter_opt2.pdf" val input_filename4 = "newsletter_opt3.pdf" val input_filename5 = "newsletter_SaveViewerOptimized.pdf" //-------------------------------------------------------------------------------- // Example 1) Optimize a PDF. try PDFDoc(Utils.getAssetTempFile(PDFNetSample.INPUT_PATH + input_filename)!!.absolutePath).use doc -> doc.initSecurityHandler() Optimizer.optimize(doc) doc.save(Utils.createExternalFile(input_filename2, mFileList).absolutePath, SDFDoc.SaveMode.LINEARIZED, null) > > catch (e: Exception) mOutputListener!!.printError(e.stackTrace) return > //-------------------------------------------------------------------------------- // Example 2) Reduce image quality and use jpeg compression for // non monochrome images. try PDFDoc(Utils.getAssetTempFile(PDFNetSample.INPUT_PATH + input_filename)!!.absolutePath).use doc -> doc.initSecurityHandler() val image_settings = Optimizer.ImageSettings() // low quality jpeg compression image_settings.setCompressionMode(Optimizer.ImageSettings.e_jpeg) image_settings.setQuality(1) // Set the output dpi to be standard screen resolution image_settings.setImageDPI(144.0, 96.0) // this option will recompress images not compressed with // jpeg compression and use the result if the new image // is smaller. image_settings.forceRecompression(true) // this option is not commonly used since it can // potentially lead to larger files. It should be enabled // only if the output compression specified should be applied // to every image of a given type regardless of the output image size //image_settings.forceChanges(true); val opt_settings = Optimizer.OptimizerSettings() opt_settings.setColorImageSettings(image_settings) opt_settings.setGrayscaleImageSettings(image_settings) Optimizer.optimize(doc, opt_settings) doc.save(Utils.createExternalFile(input_filename3, mFileList).absolutePath, SDFDoc.SaveMode.LINEARIZED, null) > > catch (e: Exception) mOutputListener!!.printError(e.stackTrace) return > //-------------------------------------------------------------------------------- // Example 3) Use monochrome image settings and default settings // for color and grayscale images. try PDFDoc(Utils.getAssetTempFile(PDFNetSample.INPUT_PATH + input_filename)!!.absolutePath).use doc -> doc.initSecurityHandler() val mono_image_settings = Optimizer.MonoImageSettings() mono_image_settings.setCompressionMode(Optimizer.MonoImageSettings.e_jbig2) mono_image_settings.forceRecompression(true) val opt_settings = Optimizer.OptimizerSettings() opt_settings.setMonoImageSettings(mono_image_settings) Optimizer.optimize(doc, opt_settings) doc.save(Utils.createExternalFile(input_filename4, mFileList).absolutePath, SDFDoc.SaveMode.LINEARIZED, null) > > catch (e: Exception) mOutputListener!!.printError(e.stackTrace) return > // ---------------------------------------------------------------------- // Example 4) Use Flattener to simplify content in this document // using default settings try PDFDoc(Utils.getAssetTempFile(PDFNetSample.INPUT_PATH + "TigerText.pdf")!!.absolutePath).use doc -> doc.initSecurityHandler() val fl = Flattener() // The following lines can increase the resolution of background // images. //fl.setDPI(300); //fl.setMaximumImagePixels(5000000); // This line can be used to output Flate compressed background // images rather than DCTDecode compressed images which is the default //fl.setPreferJPG(false); // In order to adjust thresholds for when text is Flattened // the following function can be used. //fl.setThreshold(Flattener.e_keep_most); // We use e_fast option here since it is usually preferable // to avoid Flattening simple pages in terms of size and // rendering speed. If the desire is to simplify the // document for processing such that it contains only text and // a background image e_simple should be used instead. fl.Process(doc, Flattener.e_fast) doc.save(Utils.createExternalFile("TigerText_flatten.pdf", mFileList).absolutePath, SDFDoc.SaveMode.LINEARIZED, null) > > catch (e: Exception) mOutputListener!!.printError(e.stackTrace) return > // ---------------------------------------------------------------------- // Example 5) Optimize a PDF for viewing using SaveViewerOptimized. try PDFDoc(Utils.getAssetTempFile(PDFNetSample.INPUT_PATH + input_filename)!!.absolutePath).use doc -> doc.initSecurityHandler() val opts = ViewerOptimizedOptions() // set the maximum dimension (width or height) that thumbnails will have. opts.setThumbnailSize(1500) // set thumbnail rendering threshold. A number from 0 (include all thumbnails) to 100 (include only the first thumbnail) // representing the complexity at which SaveViewerOptimized would include the thumbnail. // By default it only produces thumbnails on the first and complex pages. // The following line will produce thumbnails on every page. // opts.setThumbnailRenderingThreshold(0); doc.saveViewerOptimized(Utils.createExternalFile(input_filename5, mFileList).absolutePath, opts) > > catch (e: Exception) mOutputListener!!.printError(e.stackTrace) return > for (file in mFileList) addToFileList(file) > printFooter(outputListener) > companion object private var mOutputListener: OutputListener? = null private val mFileList = ArrayListString>() > //--------------------------------------------------------------------------------------- // The following sample illustrates how to reduce PDF file size using 'pdftron.PDF.Optimizer'. // The sample also shows how to simplify and optimize PDF documents for viewing on mobile devices // and on the Web using 'pdftron.PDF.Flattener'. // // @note Both 'Optimizer' and 'Flattener' are separately licensable add-on options to the core PDFNet license. // // ---- // // 'pdftron.PDF.Optimizer' can be used to optimize PDF documents by reducing the file size, removing // redundant information, and compressing data streams using the latest in image compression technology. // // PDF Optimizer can compress and shrink PDF file size with the following operations: // - Remove duplicated fonts, images, ICC profiles, and any other data stream. // - Optionally convert high-quality or print-ready PDF files to small, efficient and web-ready PDF. // - Optionally down-sample large images to a given resolution. // - Optionally compress or recompress PDF images using JBIG2 and JPEG2000 compression formats. // - Compress uncompressed streams and remove unused PDF objects. // // 'pdftron.PDF.Flattener' can be used to speed-up PDF rendering on mobile devices and on the Web by // simplifying page content (e.g. flattening complex graphics into images) while maintaining vector text // whenever possible. // // Flattener can also be used to simplify process of writing custom converters from PDF to other formats. // In this case, Flattener can be used as first step in the conversion pipeline to reduce any PDF to a // very simple representation (e.g. vector text on top of a background image). //--------------------------------------------------------------------------------------- >