How to merge PNG images using C#

PNG Merger .NET API

GroupDocs.Merger allows developers to combine multiple PNG documents in the preferred order and save them as a single file.

About PNG File Format

PNG, Portable Network Graphics, refers to a type of raster image file format that use loseless compression. This file format was created as a replacement of Graphics Interchange Format (GIF) and has no copyright limitations. However, PNG file format does not support animations. PNG file format supports loseless image compression that makes it popular among its users. With the passage of time, PNG has evolved as one of the mostly used image file format.

Download and Configure

Use the downloads section to download API DLLs or MSI installer or NuGet:

PM> Install-Package GroupDocs.Merger

Source PNG images

“Sample1.png” “Sample2.png” “Sample3.png”

How to merge PNG files in horizontal mode

The following example demonstrates how to merge image files in horizontal mode with several lines of C# code:

Create an instance of Merger class and pass source image file path as a constructor parameter. You may specify absolute or relative file path as per your requirements.
Create an instance of ImageJoinOptions class and pass enum value of ImageJoinMode as a constructor parameter.
Add another image file to merge with Join method and pass instance of ImageJoinOptions class as a method parameter. Repeat this step for other image documents you want to merge.
Call Merger class Save method and specify the filename for the merged image file as parameter.

// Load the source image file
using (Merger merger = new Merger(@"c:\sample1.png"))
{
    // Define image join options with horizontal join mode
    ImageJoinOptions joinOptions = new ImageJoinOptions(ImageJoinMode.Horizontal);
    // Add another image file to merge
    merger.Join(@"c:\sample2.png", joinOptions);
    // Add next image file to merge
    merger.Join(@"c:\sample3.png", joinOptions);
    // Merge image files and save result
    merger.Save(@"c:\merged.png");
}

Result merged PNG image

“Merged.png”

Code Examples

Please find more use-cases and complete C# sources of our backend and frontend examples and try them for free!

Merge PNG Live Demo

GroupDocs.Merger for .NET provides an online PNG Merger App, which allows you to try it for free and check its quality and accuracy.

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