public struct CodecsRasterPdfInfo The various RasterCodecs.GetInformation methods are used to return information about a raster image file on disk or stream. Information such as the format, size, dimension, bits per pixel are returned as members of the CodecsImageInfo object returned from RasterCodecs.GetInformation.
Raster Adobe PDF saved with the various Save methods (using any of the RasterImageFormat.RasPdfXyz flavors), contain extra information that can be obtained using RasterCodecs.GetRasterPdfInfo. This method returns an instance of CodecsRasterPdfInfo filled with these extra information as follows:
| Member | Description |
|---|---|
| IsLeadPdf |
true if the source file was created with the PDF support available in the LEADTOOLS PDF Pro, Pro Suite, Document or Medicalproducts; otherwise, false. If the value of this property is true, then other members of this structure are guaranteed to contain accurate information. If the value of this property is false and Format is one of the PDF flavors (RasterImageFormat.RasPdfXyz, then the source file is a PDF not created with LEADTOOLS, and the other members of this structure may not be guaranteed to contain accurate information (except for Width, Height, XResolution and YResolution). If this property is true, then calling RasterCodecs.DeletePage is guaranteed to work on this file. |
| BitsPerPixel |
The bits per pixel value of the raster PDF page. This is the same value used as the bitsPerPixel parameter value to the RasterCodecs.Save method used to create this file. Set the value of CodecsPdfLoadOptions.DisplayDepth to this value to load a PDF page in the original bits per pixel value it was saved at. |
| Format |
The format (compression type) of the raster PDF page, one of RasterImageFormat.RasPdfXyz. This is the same value used as the format parameter value to the RasterCodecs.Save method used to create this file. |
| Width |
The width of the page in pixels. This is the same width of the RasterImage object to the RasterCodecs.Save method used to create this file. |
| Height |
The height of the page in pixels. This is the same height of the RasterImage object to the RasterCodecs.Save method used to create this file. |
| XResolution |
The horizontal resolution of the page in dots per inch. This is the same horizontal resolution of the RasterImage object to the RasterCodecs.Save method used to create this file if CodecsPdfSaveOptions.UseImageResolution was set to true. |
| YResolution |
The vertical resolution of the page in dots per inch. This is the same vertical resolution of the RasterImage object to the RasterCodecs.Save method used to create this file. if CodecsPdfSaveOptions.UseImageResolution was set to true. |
| Version |
The version of the PDF file. This is the same value as CodecsPdfSaveOptions.Version used when saving this file with the RasterCodecs.Save method. |
This example will create a multipage raster PDF file with each page having its own size, compression and bits/pixel. Then uses CodecsRasterPdfInfo to split this file into several pages with each page saved with the original compression, size and dimension obtained from the file directly.
using Leadtools;using Leadtools.Codecs;using Leadtools.ImageProcessing;using Leadtools.ImageProcessing.Color;using Leadtools.Svg;private static void CodecsRasterPdfInfoExample(){string multiPageRasterPdfFileName = Path.Combine(LEAD_VARS.ImagesDir, "MultiPageRasterPdf.pdf");string pagesPdfFileNames = Path.Combine(LEAD_VARS.ImagesDir, "Page{0}.pdf");// Create a 4 pages PDF fileCreateMultiPageRasterPdfFile(multiPageRasterPdfFileName);// Without prior information, we will split this multi-page PDF file into// multiple single page PDF files with original size, resolution, bit-depth and compressionusing (RasterCodecs codecs = new RasterCodecs()){int pagesSaved = 0;// Get the file informationusing (CodecsImageInfo imageInfo = codecs.GetInformation(multiPageRasterPdfFileName, true)){Debug.WriteLine("Information: Format:\n Format: {0}\n Pages: {1}\n Bits/Pixel: {2}\n Size: {3} by {4}\n Resolution: {5} by {6}",imageInfo.Format, imageInfo.TotalPages, imageInfo.BitsPerPixel, imageInfo.Width, imageInfo.Height, imageInfo.XResolution, imageInfo.YResolution);Debug.WriteLine("-----------------------");// Now show the PDF specific information// Notice: GetInformation will return RasPdf as the format for all PDF files// regardless of the actual compressionif (imageInfo.Format == RasterImageFormat.RasPdf){Debug.WriteLine("Image is PDF, getting the specific info for each page");for (int i = 0; i < imageInfo.TotalPages; i++){int pageNumber = i + 1;CodecsRasterPdfInfo pdfInfo = codecs.GetRasterPdfInfo(multiPageRasterPdfFileName, i + 1);if (pageNumber == 1){Debug.WriteLine(" LEAD PDF?: {0}", pdfInfo.IsLeadPdf);Debug.WriteLine(" Version: {0}", pdfInfo.Version);}if (pdfInfo.IsLeadPdf){Debug.WriteLine("Page {0} of {1} info:\n Bits/Pixel: {2}\n Size: {3} by {4}\n Resolution: {5} by {6}\n Format: {7}",pageNumber, imageInfo.TotalPages, pdfInfo.BitsPerPixel, pdfInfo.Width, pdfInfo.Height, pdfInfo.XResolution, pdfInfo.YResolution, pdfInfo.Format);Debug.WriteLine("-----------------------");// Load this page with its original parameterscodecs.Options.RasterizeDocument.Load.XResolution = pdfInfo.XResolution;codecs.Options.RasterizeDocument.Load.YResolution = pdfInfo.YResolution;codecs.Options.Pdf.Load.DisplayDepth = pdfInfo.BitsPerPixel;using (RasterImage pageImage = codecs.Load(multiPageRasterPdfFileName, 0, CodecsLoadByteOrder.BgrOrGray, pageNumber, pageNumber)){Debug.WriteLine("Page {0} of {1} loaded:\n Bits/Pixel: {2}\n Size: {3} by {4}\n Resolution: {5} by {6}",pageNumber, imageInfo.TotalPages, pageImage.BitsPerPixel, pageImage.Width, pageImage.Height, pageImage.XResolution, pageImage.YResolution);Debug.WriteLine("-----------------------");// Setup the PDF save optionscodecs.Options.Pdf.Save.UseImageResolution = true;codecs.Options.Pdf.Save.Version = pdfInfo.Version;// Save this page to a separate filestring pagePdfFileName = string.Format(pagesPdfFileNames, pageNumber);codecs.Save(pageImage, pagePdfFileName, pdfInfo.Format, pdfInfo.BitsPerPixel);pagesSaved++;}}}}}// We are done, now show the info of the generated filesfor (int i = 0; i < pagesSaved; i++){int pageNumber = i + 1;string pagePdfFileName = string.Format(pagesPdfFileNames, pageNumber);CodecsRasterPdfInfo pdfInfo = codecs.GetRasterPdfInfo(pagePdfFileName, 1);Debug.WriteLine("Page {0} of {1} info:\n Bits/Pixel: {2}\n Size: {3} by {4}\n Resolution: {5} by {6}\n Format: {7}",pageNumber, pagesSaved, pdfInfo.BitsPerPixel, pdfInfo.Width, pdfInfo.Height, pdfInfo.XResolution, pdfInfo.YResolution, pdfInfo.Format);Debug.WriteLine("-----------------------");}}}private static void CreateMultiPageRasterPdfFile(string pdfFileName){string sourceFile = Path.Combine(LEAD_VARS.ImagesDir, "Sample1.cmp");// Delete the destination PDF file if existsif (System.IO.File.Exists(pdfFileName)){System.IO.File.Delete(pdfFileName);}using (RasterCodecs codecs = new RasterCodecs()){// Save to PDF v1.4codecs.Options.Pdf.Save.Version = CodecsRasterPdfVersion.V14;// Save using image resolutioncodecs.Options.Pdf.Save.UseImageResolution = true;// Load the source file to use for each pageusing (RasterImage pageImage = codecs.Load(sourceFile, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1)){Debug.WriteLine("Original image dimension:\n Size: {0} by {1}\n Resolution: {2} by {3}",pageImage.Width, pageImage.Height, pageImage.XResolution, pageImage.YResolution);// Array of bits/pixel and compression to use when saving the pagesint[] bitsPerPixel ={1,8,24};RasterImageFormat[] formats ={RasterImageFormat.RasPdfG4,RasterImageFormat.RasPdfLzw,RasterImageFormat.RasPdfJpeg422};int pageCount = bitsPerPixel.Length;for (int i = 0; i < pageCount; i++){// Append this page with given formatDebug.WriteLine("Saving page {0} of {1} using {2} at {3}", i + 1, pageCount, bitsPerPixel[i], formats[i]);codecs.Save(pageImage, pdfFileName, formats[i], bitsPerPixel[i], 1, 1, -1, CodecsSavePageMode.Append);}}Debug.WriteLine("-----------------------");}}static class LEAD_VARS{public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images";}