Сжатие PDF документа используя C#, VB.NET
12 июля 2024
/// <summary> /// Packs the PDF document. /// </summary> /// <param name="inPdfFilename">The input PDF filename.</param> /// <param name="outPdfFilename">The output PDF filename.</param> public static void PackDocument(string inPdfFilename, string outPdfFilename) { // create compressor with empty compression settings Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand compressor = Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand.CreateEmptyCompressor(); // specify that compressor must use maximum Flate compression level (best compression) compressor.FlateCompressionLevel = 9; // specify that compressor must recompress all resource that uses None, LZW, Flate compression using Flate compression compressor.RecompressFlateCompression = true; compressor.UseFlateInsteadLzwCompression = true; compressor.UseFlateInsteadNoneCompression = true; // specify that compressor must remove incremental update info and unused objects compressor.PackDocument = true; // if version of PDF document is lower than 1.7 if (GetPdfDocumentVersion(inPdfFilename) < 17) { // set output format to PDF 1.7 compressor.DocumentPackFormat = Vintasoft.Imaging.Pdf.PdfFormat.Pdf_17; } // compress PDF document compressor.Compress(inPdfFilename, outPdfFilename); } /// <summary> /// Returns the PDF document version. /// </summary> /// <param name="pdfFilename">The PDF filename.</param> /// <returns>The version number in dual-digit format (10,11,12,13,14,15,16,17,20,...).</returns> private static int GetPdfDocumentVersion(string pdfFilename) { using (Vintasoft.Imaging.Pdf.PdfDocument document = new Vintasoft.Imaging.Pdf.PdfDocument(pdfFilename)) return document.Format.VersionNumber; }
/// <summary> /// Subsets fonts in PDF document. /// </summary> /// <param name="inPdfFilename">The input PDF filename.</param> /// <param name="outPdfFilename">The output PDF filename.</param> public static void SubsetFonts(string inPdfFilename, string outPdfFilename) { // create compressor with empty compression settings Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand compressor = Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand.CreateEmptyCompressor(); // specify that compressor must subset fonts in PDF document compressor.SubsetFonts = true; // compress PDF document compressor.Compress(inPdfFilename, outPdfFilename); }
/// <summary> /// Detects "read color depth" of PDF image resources and compress PDF document with intent to view in 150DPI. /// </summary> /// <param name="inPdfFilename">The input PDF filename.</param> /// <param name="outPdfFilename">The output PDF filename.</param> public static void CompressToViewIn150DPI(string inPdfFilename, string outPdfFilename) { // create compressor that will compress PDF document using lossy compression algorithms Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand compressor = Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand.CreateLossyCompressor(150, false, false, false); // specify that compressor must use JPEG compression for color images compressor.ColorImagesCompression = Vintasoft.Imaging.Pdf.PdfCompression.Jpeg; // specify that compressor must set JPEG quality to 70 compressor.ColorImagesCompressionSettings.JpegQuality = 70; // specify that compressor must detect if image is bitonal image and use optimal compression for bitonal image compressor.DetectBitonalImageResources = true; // specify that compressor must detect if image is black-white image and use optimal compression for black-white image compressor.DetectBlackWhiteImageResources = true; // specify that compressor must detect if image is grayscale image and use optimal compression for grayscale image compressor.DetectGrayscaleImageResources = true; // compress PDF document compressor.Compress(inPdfFilename, outPdfFilename); }
/// <summary> /// Removes unused and duplicated resources in the PDF document. /// </summary> /// <param name="inPdfFilename">The input PDF filename.</param> /// <param name="outPdfFilename">The output PDF filename.</param> public static void RemoveUnsusedResources(string inPdfFilename, string outPdfFilename) { // create compressor with empty compression settings Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand compressor = Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand.CreateEmptyCompressor(); // specify that compressor must remove duplicate resources from PDF document compressor.RemoveDuplicateResources = true; // specify that compressor must remove unused names resources from PDF document compressor.RemoveUnusedNamedResources = true; // specify that compressor must remove unused names from PDF document compressor.RemoveUnusedNames = true; // specify that compressor must remove unused pages from PDF document compressor.RemoveUnusedPages = true; // specify that compressor must remove invalid bookmarks from PDF document compressor.RemoveInvalidBookmarks = true; // specify that compressor must remove invalid links from PDF document compressor.RemoveInvalidLinks = true; // compress PDF document compressor.Compress(inPdfFilename, outPdfFilename); }
/// <summary> /// Removes metadata, bookmarks, document information, embedded files, embedded thumbnails, interactive form and structure tree of the PDF document. /// </summary> /// <param name="inPdfFilename">The input PDF filename.</param> /// <param name="outPdfFilename">The output PDF filename.</param> public static void RemoveObjects(string inPdfFilename, string outPdfFilename) { // create compressor with empty compression settings Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand compressor = Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand.CreateEmptyCompressor(); // specify that compressor must remove metadata from PDF document compressor.RemoveMetadata = true; // specify that compressor must remove bookmarks from PDF document compressor.RemoveBookmarks = true; // specify that compressor must remove document information from PDF document compressor.RemoveDocumentInformation = true; // specify that compressor must remove embedded files from PDF document compressor.RemoveEmbeddedFiles = true; // specify that compressor must remove embedded thumbnails from PDF document compressor.RemoveEmbeddedThumbnails = true; // specify that compressor must remove interactive form from PDF document compressor.RemoveInteractiveForm = true; // specify that compressor must remove structure tree from PDF document compressor.RemoveStructureTree = true; // compress PDF document compressor.Compress(inPdfFilename, outPdfFilename); }
/// <summary> /// Flatten an annotations and remove intractive form of the PDF document. /// </summary> /// <param name="inPdfFilename">The input PDF filename.</param> /// <param name="outPdfFilename">The output PDF filename.</param> public static void FlattenAnnotations(string inPdfFilename, string outPdfFilename) { // create compressor with empty compression settings Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand compressor = Vintasoft.Imaging.Pdf.Processing.PdfDocumentCompressorCommand.CreateEmptyCompressor(); // specify that compressor must remove interactive form from PDF document compressor.RemoveInteractiveForm = true; // specify that compressor must flatten annotations in PDF document compressor.FlattenAnnotations = true; // compress PDF document compressor.Compress(inPdfFilename, outPdfFilename); }