LEADTOOLS Image File Support (Leadtools.Codecs assembly)
LEAD Technologies, Inc

SaveAsync(RasterImage,ILeadStream,RasterImageFormat,Int32,Int32,Int32,Int32,CodecsSavePageMode) Method

Example 





Leadtools.Codecs Namespace > RasterCodecs Class > SaveAsync Method : SaveAsync(RasterImage,ILeadStream,RasterImageFormat,Int32,Int32,Int32,Int32,CodecsSavePageMode) Method
The Leadtools.RasterImage object that holds the image data.
An Leadtools.ILeadStream where the image data will be saved.
The output file format. For valid values, Summary of All Supported Image File Formats.
Resulting file's pixel depth. Note that not all bits per pixel are available to all file formats. For valid values, refer to Summary of All Supported Image File Formats. If bitsPerPixel is 0, the image will be stored using the closet bits/pixel value supported by that format. For example, if a file format supports 1, 4, and 24 bits/pixel, and RasterImage.BitsPerPixel is 5, the file will be stored as 24 bit. Likewise, if RasterImage.BitsPerPixel is 2, the file will be stored as 4 bit.
1-based index of the first page in image to save.
1-based index of the last page in image to save. Pass -1 to save from firstPage to the last page in image.
1-based index of the first output page. If the output file already exists, then this parameter lets you control which pages to overwrite and/or where to append the new pages.

Determines how to handle the page when saving to multipage formats. This can be one of the following:

Value Meaning
CodecsSavePageMode.Append Append the new page(s) to the end of the file. If the file does not exist, this option will create the file and add the pages to it. firstSavePageNumber is not used.
CodecsSavePageMode.Insert Insert the new page(s) at the index specified by firstSavePageNumber.
CodecsSavePageMode.Replace Replace the page(s) starting at the index specified by firstSavePageNumber.
CodecsSavePageMode.Overwrite Overwrite the page(s) starting at the index specified by firstSavePageNumber.
Saves a Leadtools.RasterImage to a stream in any of the supported compressed or uncompressed formats. .NET support WinRT support
Syntax
public IAsyncAction SaveAsync( 
   RasterImage image,
   ILeadStream stream,
   RasterImageFormat format,
   int bitsPerPixel,
   int firstPage,
   int lastPage,
   int firstSavePageNumber,
   CodecsSavePageMode pageMode
)
'Declaration
 
Public Overloads Function SaveAsync( _
   ByVal image As RasterImage, _
   ByVal stream As ILeadStream, _
   ByVal format As RasterImageFormat, _
   ByVal bitsPerPixel As Integer, _
   ByVal firstPage As Integer, _
   ByVal lastPage As Integer, _
   ByVal firstSavePageNumber As Integer, _
   ByVal pageMode As CodecsSavePageMode _
) As IAsyncAction
'Usage
 
Dim instance As RasterCodecs
Dim image As RasterImage
Dim stream As ILeadStream
Dim format As RasterImageFormat
Dim bitsPerPixel As Integer
Dim firstPage As Integer
Dim lastPage As Integer
Dim firstSavePageNumber As Integer
Dim pageMode As CodecsSavePageMode
Dim value As IAsyncAction
 
value = instance.SaveAsync(image, stream, format, bitsPerPixel, firstPage, lastPage, firstSavePageNumber, pageMode)
public IAsyncAction SaveAsync( 
   RasterImage image,
   ILeadStream stream,
   RasterImageFormat format,
   int bitsPerPixel,
   int firstPage,
   int lastPage,
   int firstSavePageNumber,
   CodecsSavePageMode pageMode
)
 function Leadtools.Codecs.RasterCodecs.SaveAsync(RasterImage,ILeadStream,RasterImageFormat,Int32,Int32,Int32,Int32,CodecsSavePageMode)( 
   image ,
   stream ,
   format ,
   bitsPerPixel ,
   firstPage ,
   lastPage ,
   firstSavePageNumber ,
   pageMode 
)

public:
IAsyncAction^ SaveAsync( 
   RasterImage^ image,
   ILeadStream^ stream,
   RasterImageFormat format,
   int bitsPerPixel,
   int firstPage,
   int lastPage,
   int firstSavePageNumber,
   CodecsSavePageMode pageMode
)

Parameters

image
The Leadtools.RasterImage object that holds the image data.
stream
An Leadtools.ILeadStream where the image data will be saved.
format
The output file format. For valid values, Summary of All Supported Image File Formats.
bitsPerPixel
Resulting file's pixel depth. Note that not all bits per pixel are available to all file formats. For valid values, refer to Summary of All Supported Image File Formats. If bitsPerPixel is 0, the image will be stored using the closet bits/pixel value supported by that format. For example, if a file format supports 1, 4, and 24 bits/pixel, and RasterImage.BitsPerPixel is 5, the file will be stored as 24 bit. Likewise, if RasterImage.BitsPerPixel is 2, the file will be stored as 4 bit.
firstPage
1-based index of the first page in image to save.
lastPage
1-based index of the last page in image to save. Pass -1 to save from firstPage to the last page in image.
firstSavePageNumber
1-based index of the first output page. If the output file already exists, then this parameter lets you control which pages to overwrite and/or where to append the new pages.
pageMode

Determines how to handle the page when saving to multipage formats. This can be one of the following:

Value Meaning
CodecsSavePageMode.Append Append the new page(s) to the end of the file. If the file does not exist, this option will create the file and add the pages to it. firstSavePageNumber is not used.
CodecsSavePageMode.Insert Insert the new page(s) at the index specified by firstSavePageNumber.
CodecsSavePageMode.Replace Replace the page(s) starting at the index specified by firstSavePageNumber.
CodecsSavePageMode.Overwrite Overwrite the page(s) starting at the index specified by firstSavePageNumber.

Return Value

An asynchronous save operation on a RasterCodecs object.
Remarks

If the output file format supports multipage and then all the pages in image will be saved to the file.

If the image is 8 bits per pixel or greater, use the LEAD CMP format or one of the JPEG (JTIF or JFIF) formats to save disk space.

If the image is 1-bit per pixel, use the LEAD 1-bit format or a CCITT Group 3 or 4 format to save disk space.

If the image has a region, the region stored in the image will be saved, if the image is saved as one of the TIFF file formats. For more information, refer to Saving A Region. Note, however, that the ability to save a region inside a TIFF file must be unlocked. This requires a Document Imaging or Medical Imaging toolkit.

Only TIFF and DICOM file formats are capable of saving images that have been window-leveled. Images can be window-leveled by calling RasterImage.WindowLevel and specifying RasterWindowLevelMode.PaintAndProcessing, by using the Leadtools.ImageProcessing.Core.WindowLevelCommand or by loading an image from a file format that supports Window Leveling. If a window-leveled image is saved as any other file format, the image data will be converted before being saved. For more information, refer to Saving Window-Leveled Images.

Use the CodecsSaveOptions class to set up other save options parameters before calling this method.

Use to the SaveImage event to provide progress feedback or to set or modify the saved image data.

This method supports signed data images, but only DICOM and TIFF formats support signed data. This method will throw an exception if you attempt to save a signed image to a format other than DICOM or TIFF.

In LEADTOOLS version 17 and up, when saving a colored image (such as a 24-bits per pixel image) to bitonal (1-bit per pixel), the RasterCodecs object will not use any dithering when converting the image data. This is done because dithering is not the recommended when converting colored images containing text for document processing such as OCR and Barcode. The resulting text will be fuzzy and hard for a recognition engine to process. To save a colored image as bitonal with Floyd-Stein dithering (the behavior of LEADTOOLS 16.5 and earlier) use CodecsSaveOptions.UseImageDitheringMethod along with RasterImage.DitheringMethod as illustrated below:

    

            // 'codecs' is the RasterCodecs to use when saving
            // 'image' is a colored RasterImage object
            // Setup FloydStein dithering:
            codecs.Options.Save.UseImageDitheringMethod = true;
            image.DitheringMethod = RasterDitheringMethod.FloydStein;
            // Save the image as 1-bpp with auto-dithering:
            codecs.Save(image, fileName, RasterImageFormat.Tif, 1);

For information about quality factors, refer to Compression Quality Factors.

Example
  
RasterCodecsExamples.prototype.SaveFile2Example = function () {
   Tools.SetLicense();
   with (Leadtools) {
      with (Leadtools.Codecs) {
         var codecs = new RasterCodecs();
         var destFileName = "Image1_SaveFile2.tif";
         var image;
         var pageCount = 4;
         var files = [];
         var saveFile;
         // Create a multi-page image for testing purposes
         for (var i = 1; i <= 4; i++) {
            files[i] = "Assets\\OCR" + i + ".tif";
         }

         var promises = files.map(function (srcFileName) {
            return Tools.AppInstallFolder().getFileAsync(srcFileName).then(function (loadFile) {
               return codecs.loadAsync(LeadStreamFactory.create(loadFile))
            })
            .then(function (pageImage) {

               if (image == null)
                  image = pageImage;
               else {
                  image.addPage(pageImage);
                  pageImage.close();
               }
            });
         });

         return WinJS.Promise.join(promises).then(function () {
            // Save all the pages to the file
            // The file should have 4 pages now: 1, 2, 3, 4
            return Tools.AppLocalFolder().createFileAsync(destFileName)
         })
         .then(function (saveFileX) {
            saveFile = saveFileX;
            return codecs.saveAsync(image, LeadStreamFactory.create(saveFile), RasterImageFormat.tif, 1, 1, pageCount, 1, CodecsSavePageMode.overwrite)
         })
         .then(function () {
            image.close();

            // Load the 3rd page and insert it as the second
            // The file should have 5 pages now: 1, 3, 2, 3, 4
            return codecs.loadAsync(LeadStreamFactory.create(saveFile), 0, CodecsLoadByteOrder.bgrOrGray, 3, 3)
         })
         .then(function (img) {
            image = img;
            return codecs.saveAsync(image, LeadStreamFactory.create(saveFile), RasterImageFormat.tif, 1, 1, 1, 2, CodecsSavePageMode.insert)
         })
         .then(function () {
            image.close();


            // Load the last page, and insert it as the first
            // The file should have 5 pages now: 4, 1, 3, 2, 3, 4
            return codecs.loadAsync(LeadStreamFactory.create(saveFile), 0, CodecsLoadByteOrder.bgrOrGray, 5, 5)
         })
         .then(function (img) {
            image = img;
            return codecs.saveAsync(image, LeadStreamFactory.create(saveFile), RasterImageFormat.tif, 1, 1, 1, 1, CodecsSavePageMode.insert)
         })
         .then(function () {
            image.close();

            // Replace the 5th page with the 2nd
            // The file should have 5 pages now: 4, 1, 3, 2, 1, 4
            return codecs.loadAsync(LeadStreamFactory.create(saveFile), 0, CodecsLoadByteOrder.bgrOrGray, 2, 2)
         })
         .then(function (img) {
            image = img;
            return codecs.saveAsync(image, LeadStreamFactory.create(saveFile), RasterImageFormat.tif, 1, 1, 1, 5, CodecsSavePageMode.replace)
         })
         .then(function () {
            image.close();


            // Delete the 2nd and 6th pages
            // The file should have 5 pages now: 4, 3, 2, 1
            return codecs.deletePageAsync(LeadStreamFactory.create(saveFile), 2)
         })
         .then(function () {
            // Notice, -1 because we already deleted a page, so 6th page is not 5th
            return codecs.deletePageAsync(LeadStreamFactory.create(saveFile), 6 - 1)
         })
         .then(function () {
            // Clean up
            codecs.close();
         });
      }
   }
}
[TestMethod]
public async Task SaveFile2Example()
{
   RasterCodecs codecs = new RasterCodecs();
   string destFileName = @"Image1_SaveFile2.tif";
   const int pageCount = 4;
   // Create a multi-page image for testing purposes
   RasterImage image = null;
   for (int i = 1; i <= 4; i++)
   {
      string srcFileName = String.Format(@"Assets\OCR{0}.tif", i);
      StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(srcFileName);
      RasterImage pageImage = await codecs.LoadAsync(LeadStreamFactory.Create(loadFile));
      if (image == null)
         image = pageImage;
      else
      {
         image.AddPage(pageImage);
         pageImage.Dispose();
      }
   }

   // Save all the pages to the file
   // The file should have 4 pages now: 1, 2, 3, 4
   StorageFile saveFile = await Tools.AppLocalFolder.CreateFileAsync(destFileName);
   await codecs.SaveAsync(image, LeadStreamFactory.Create(saveFile), RasterImageFormat.Tif, 1, 1, pageCount, 1, CodecsSavePageMode.Overwrite);
   image.Dispose();

   // Load the 3rd page and insert it as the second
   // The file should have 5 pages now: 1, 3, 2, 3, 4
   image = await codecs.LoadAsync(LeadStreamFactory.Create(saveFile), 0, CodecsLoadByteOrder.BgrOrGray, 3, 3);
   await codecs.SaveAsync(image, LeadStreamFactory.Create(saveFile), RasterImageFormat.Tif, 1, 1, 1, 2, CodecsSavePageMode.Insert);
   image.Dispose();

   // Load the last page, and insert it as the first
   // The file should have 5 pages now: 4, 1, 3, 2, 3, 4
   image = await codecs.LoadAsync(LeadStreamFactory.Create(saveFile), 0, CodecsLoadByteOrder.BgrOrGray, 5, 5);
   await codecs.SaveAsync(image, LeadStreamFactory.Create(saveFile), RasterImageFormat.Tif, 1, 1, 1, 1, CodecsSavePageMode.Insert);
   image.Dispose();

   // Replace the 5th page with the 2nd
   // The file should have 5 pages now: 4, 1, 3, 2, 1, 4
   image = await codecs.LoadAsync(LeadStreamFactory.Create(saveFile), 0, CodecsLoadByteOrder.BgrOrGray, 2, 2);
   await codecs.SaveAsync(image, LeadStreamFactory.Create(saveFile), RasterImageFormat.Tif, 1, 1, 1, 5, CodecsSavePageMode.Replace);
   image.Dispose();

   // Delete the 2nd and 6th pages
   // The file should have 5 pages now: 4, 3, 2, 1
   await codecs.DeletePageAsync(LeadStreamFactory.Create(saveFile), 2);
   // Notice, -1 because we already deleted a page, so 6th page is not 5th
   await codecs.DeletePageAsync(LeadStreamFactory.Create(saveFile), 6 - 1);

   // Clean up
   codecs.Dispose();
}
Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

See Also

Reference

RasterCodecs Class
RasterCodecs Members
Overload List
Loading and Saving Images
Loading and Saving Large Tiff Files
Speeding Up 1-Bit Documents
Working with Markers
Fast File Info

 

 

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