Information Technology Tips

Introduction I have googled and wrote small code snippet for parsing and printing image metadata in Java. The biggest problem of this program (or maybe Java standard imageio library) cannot read jpeg exif data. I have found following solutions for this problem. Java Advanced Image API (Plugin) <- Looks quite obsolete. I also found the project in java.net - jai-imageio , but again not maintained for a long time :( Apache Commons Imaging : Tested in Java: Available Tags for Extracting Metadata Using Apache Commons Imaging Sanselan : Tested in Java: Read Exif Metadata Using Sanselan metadata-extractor : Testes in Java: Read Exif Metadata Using metadata-extractor J-Exiftool Both libraries are not updated recently but I guess it's because they don't need anymore enhancements. I will investigate and re-post how to use these image libraries soon... In this post, I only show you the code snippet for parsing and printing image metadata using Java standard Image API ...

I have written simple debug code for printing out PropertyItems in System.Drawing.Image object. The key part of the code: mapping between Id property of PropertyItem and description of associated to the property item. decode PropertyItem value (byte array) to human readable format string The code itself will be shown at the bottom of this post. Below is a sample image which will be passed to the program and the corresponding output generated by the program. Property Item 1 Id: 0x10e Type: 2 Length: 17 bytes Type String: ASCII Descriotion: PropertyTagImageDescription Value : MetaData Example Property Item 2 Id: 0x131 Type: 2 Length: 7 bytes Type String: ASCII Descriotion: PropertyTagSoftwareUsed Value : Picasa Property Item 3 Id: 0x9000 Type: 7 Length: 4 bytes Type String: Undefined Descriotion: PropertyTagExifVer Value : Property Item 4 Id: 0xa002 Type: 4 Length: 4 bytes Type String: Long (3...

I wrote the post for extracting gif frame image from an animated gif image in Java - Java: Extract Gif Images From An Animated Gif Image . In this post, I have tried to do same thing in C# as well :D Code using System.Drawing; using System.Drawing.Imaging; namespace Utility { public class GifImageUtils { public static void SaveAnimatedGifFrames(string path, string outDir) { var gifImg = Image.FromFile(path); var dimension = new FrameDimension(gifImg.FrameDimensionsList[0]); int frameCount = gifImg.GetFrameCount(dimension); for (int i = 0; i < frameCount; i++) { gifImg.SelectActiveFrame(dimension, i); // create a frame image from the original source image - clone is mandatory var frame = (Image)gifImg.Clone(); frame.Save(outDir+"/"+i+".gif", ImageFormat.Gif); } } } } Exa...

Creating Indexed PNG in C# In C#, there are mainly two namespaces to creating image... System.Drawing namespace System.Windows.Media namespace I've already written the post for creating indexed png using System.Drawing namespace classes - Create Indexed PNG Using C# .Net . So, in this post, I will show you how to create indexed png using classes under System.Windows.Media namespace. Preparation for Using Classes Under System.Windows.Media You need to add following dlls to your project reference in order to handle images using classes under System.Windows.Media. PresentationCore.dll Xaml.dll WindowsBase.dll Creating Palette Based Indexed Image If you would like to create indexed png, first of all, you should create color palette which can hold max 256 colors. Creating color palette is trivial. Please see the below example code: var colors = new List<Color>(); colors.Add(Color.FromRgb(255, 0, 0)); // 0 - red colors.Add(Color.FromRgb(0, 255, 0)); // 1 -...

In this post, I will show you the code for extracting gif frame images from an animated gif image. I will show you two types of code: Simply extracting gif images stored in the original animated gif image Creating gif image by rendering and accumulating each gif frames stored in the original gif image Code for Extracting Gif Image From An Animated Gif Java Code package com.dukesoftware.utils.image; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import javax.imageio.ImageIO; import javax.imageio.ImageReader; import javax.imageio.stream.ImageInputStream; public class GifImageUtils { public static void main(String[] args) throws IOException { String sourceGif = "c:/temp/SmallFullColourGIF.gif"; saveAnimatedGifFramePartsToImage(sourceGif, "c:/temp/gif_parts"); } public static void saveAnimatedGifFramePartsToImage(String input, String outDir) throws IOException { ImageReade...