RasterTagMetadata Class

Summary

Extends the RasterMetadata class to provide functionality for dealing with tag metadata stored within various image file formats.

Syntax

Objective-C

C++/CLI

Java

Python

[SerializableAttribute()] 
public class RasterTagMetadata : RasterMetadata

@interface LTRasterTagMetadata : LTRasterMetadata

public class RasterTagMetadata 
    extends RasterMetadata 
    implements java.io.Serializable

[SerializableAttribute()] 
public ref class RasterTagMetadata : public RasterMetadata

class RasterTagMetadata(RasterMetadata):

Remarks

The TIFF file formats support a number of comments that are saved and loaded using predefined tags.

If the comments do not meet your needs, you can define your own tag for saving additional non-raster data in a TIFF file. For example, you may want to define a tag to save annotations.

The TIFF 6.0 Specification sets aside a range of private tags that developers can define. To avoid conflicts with files created by other developers, you can register your tag by contacting Adobe Developer Relations. The E-Mail address posted on The Unofficial TIFF Home Page is [email protected].

Some restrictions apply to this function if you use an IFD to indicate to which page to write the metadata. See the Loading And Saving Large TIFF Files topic for more information.

Example

This example will save then load some tags to/from a tif file.

using Leadtools; 
using Leadtools.Codecs; 
 
 
public void RasterTagMetadataExample() 
{ 
	RasterCodecs codecs = new RasterCodecs(); 
	codecs.ThrowExceptionsOnInvalidImages = true; 
 
	string srcFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"); 
	string destFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1_tags.tif"); 
 
	// Load the image 
	RasterImage image = codecs.Load(srcFileName); 
 
	// add the tags 
	const int tagSoftware = 0x8001; 
 
	RasterTagMetadata tag; 
 
	// Ascii 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.Ascii; 
	tag.FromAscii("Test String"); 
	image.Tags.Add(tag); 
 
	// Byte 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.Byte; 
	byte[] byteArray = new byte[1]; 
	byteArray[0] = 10; 
	tag.FromByte(byteArray); 
	image.Tags.Add(tag); 
 
	// SByte 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.SByte; 
	sbyte[] sbyteArray = new sbyte[1]; 
	sbyteArray[0] = -45; 
	tag.FromSByte(sbyteArray); 
	image.Tags.Add(tag); 
 
	// Int16 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.Int16; 
	short[] shortArray = new short[1]; 
	shortArray[0] = 64; 
	tag.FromInt16(shortArray); 
	image.Tags.Add(tag); 
 
	// Uint16 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.UInt16; 
	ushort[] uint16Array = new ushort[1]; 
	uint16Array[0] = 50; 
	tag.FromUInt16(uint16Array); 
	image.Tags.Add(tag); 
 
	// Int32 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.Int32; 
	int[] intArray = new int[1]; 
	intArray[0] = -1326; 
	tag.FromInt32(intArray); 
	image.Tags.Add(tag); 
 
	// Uint32 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.UInt32; 
	uint[] uintArray = new uint[1]; 
	uintArray[0] = 1326; 
	tag.FromUInt32(uintArray); 
	image.Tags.Add(tag); 
 
	// single 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.Single; 
	float[] singleArray = new float[1]; 
	singleArray[0] = 4.53f; 
	tag.FromSingle(singleArray); 
	image.Tags.Add(tag); 
 
	// Double 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.Double; 
	double[] doubleArray = new double[1]; 
	doubleArray[0] = 7.1; 
	tag.FromDouble(doubleArray); 
	image.Tags.Add(tag); 
 
	// Rational 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.Rational; 
	RasterMetadataRational[] rational = new RasterMetadataRational[1]; 
	rational[0] = new RasterMetadataRational(); 
	rational[0].Numerator = 3; 
	rational[0].Denominator = 2; 
	tag.FromRational(rational); 
	image.Tags.Add(tag); 
 
	// URational 
	tag = new RasterTagMetadata(); 
	tag.Id = tagSoftware; 
	tag.DataType = RasterTagMetadataDataType.URational; 
	RasterMetadataURational[] urational = new RasterMetadataURational[1]; 
	urational[0] = new RasterMetadataURational(3, 2); 
	tag.FromURational(urational); 
	image.Tags.Add(tag); 
 
	// Save the image and its tags to the destination tiff file 
	codecs.Options.Save.Tags = true; 
	codecs.Save(image, destFileName, RasterImageFormat.Tif, 1); 
 
	// Enumerate the tags from the file 
	codecs.TagFound += new EventHandler<CodecsEnumTagsEventArgs>(codecs_TagFound); 
	codecs.EnumTags(destFileName, 1); 
 
	// clean up 
	image.Dispose(); 
	codecs.Dispose(); 
} 
 
void codecs_TagFound(object sender, CodecsEnumTagsEventArgs e) 
{ 
	Console.WriteLine("Found tag id = {0}, count = {1}, type = {2}", e.Id, e.Count, e.MetadataType); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
}

Requirements

Target Platforms

Reference

RasterTagMetadata Members

Leadtools Namespace

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Help Version 22.0.2023.5.16