ReadLoadResolutions(string,int) Method

Summary

Examines a page in a file to determine which resolutions it contains.

Syntax

Objective-C

C++

public LeadSize[] ReadLoadResolutions( 
   string fileName, 
   int pageNumber 
)

Public Overloads Function ReadLoadResolutions( _ 
   ByVal fileName As String, _ 
   ByVal pageNumber As Integer _ 
) As LeadSize()

- (nullable NSArray<NSValue/*CGSize*/ *> *)loadResolutionsForFile:(NSString *)file  
                                                             pageNumber:(NSInteger)pageNumber  
                                                                  error:(NSError **)error

public: 
array<LeadSize>^ ReadLoadResolutions(  
   String^ fileName, 
   int pageNumber 
)

Parameters

fileName
A String containing the name of the file to query.

pageNumber
An Int32 that indicates the page number.

Return Value

A LeadSize structure containing the available resolutions.

Remarks

A FlashPix, PhotoCD, JPEG 2000 or JBIG/JBIG2 file can contain more than one copy of the same image, each at a different physical resolution (width and height in pixels).

multipage files (like TIF) containing compressions listed above (eg: JPEG 2000 or JBIG/JBIG2) can also contain more than one copy of the same image, each at a different physical resolution (width and height in pixels).

After you get the available resolutions, you can use any of the following to specify the one to be loaded:

The pages numbers start with 1, so set pageNumber to 2 to read the resolutions from the second page. If you set pageNumber to 1, the function behaves like the equivalent function without the pageNumber parameter.

For more information, refer to Implementing JBIG Features.

Example

This example shows how many physical resolutions are available in page 2, selects the smallest one, then loads the file.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Svg; 
using LeadtoolsExamples.Common; 
 
void ReadLoadResolutionsTiffExample(string tiffFileName, int pageNumber) 
{ 
   RasterCodecs codecs = new RasterCodecs(); 
 
   // Get the number of resolutions (sizes) available in second page of this file 
   // Make sure you run this for a tiff file with 2 pages, second page using JPEG 2000 compression 
   LeadSize[] resolution = codecs.ReadLoadResolutions(tiffFileName, pageNumber); 
   if (resolution.Length > 0) 
   { 
      Console.WriteLine("{0} resolutions available", resolution.Length); 
      for (int i = 0; i < resolution.Length; i++) 
         Console.WriteLine("{0}: {1} by {2}", i, resolution[i].Width, resolution[i].Height); 
 
      // Set the size to load, the smallest size in this case */ 
      codecs.Options.Tiff.Load.J2kResolution = resolution[resolution.Length - 1]; 
 
      // Get the info in of the image to show its original size 
      CodecsImageInfo info = codecs.GetInformation(tiffFileName, false, pageNumber); 
      Console.WriteLine("Size of image according to GetInformation is {0} by {1}", info.Width, info.Height); 
 
      // Load the image, keeping the bits per pixel of the file 
      RasterImage image = codecs.Load(tiffFileName, pageNumber); 
      Console.WriteLine("Size of image loaded is {0} by {1}", image.Width, image.Height); 
 
      image.Dispose(); 
   } 
   else 
      Console.WriteLine("No resolutions found"); 
 
   // Clean up 
   codecs.Dispose(); 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing 
Imports Leadtools.ImageProcessing.Color 
Imports Leadtools.Drawing 
Imports Leadtools.Svg 
 
Private Sub ReadLoadResolutionsTiffExample(ByVal tiffFileName As String, ByVal pageNumber As Int32) 
   Dim codecs As RasterCodecs = New RasterCodecs() 
 
   ' Get the number of resolutions (sizes) available in this file 
   Dim resolution As LeadSize() = codecs.ReadLoadResolutions(tiffFileName, pageNumber) 
   If resolution.Length > 0 Then 
      Console.WriteLine("{0} resolutions available", resolution.Length) 
      Dim i As Integer = 0 
      Do While i < resolution.Length 
         Console.WriteLine("{0}: {1} by {2}", i, resolution(i).Width, resolution(i).Height) 
         i += 1 
      Loop 
 
      ' Set the size to load, the smallest size in this case */ 
      codecs.Options.Tiff.Load.J2kResolution = resolution(resolution.Length - 1) 
 
      ' Get the info about the image to show its original size 
      Dim info As CodecsImageInfo = codecs.GetInformation(tiffFileName, False, pageNumber) 
      Console.WriteLine("Size of image according to GetInformation is {0} by {1}", info.Width, info.Height) 
 
      ' Load the image, keeping the bits per pixel of the file 
      Dim image As RasterImage = codecs.Load(tiffFileName, pageNumber) 
      Console.WriteLine("Size of image loaded is {0} by {1}", image.Width, image.Height) 
 
      image.Dispose() 
   Else 
      Console.WriteLine("No resolutions found") 
   End If 
 
   ' Clean up 
   codecs.Dispose() 
End Sub

Requirements

Target Platforms

Reference

RasterCodecs Class

RasterCodecs Members

Overload List

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Help Version 20.0.2020.4.3