Create slide thumbnails

Overview

Render a selected slide at thumbnail dimensions for a gallery, file browser or navigation panel. You can choose any slide in the presentation and set the output size, so previews do not have to be limited to the first slide.

Usage example

This C# example uses Aspose.Slides for .NET. It creates a 640 × 360 point slide with a red text rectangle and renders it at one-quarter scale. The resulting thumbnail.png is 160 × 90 pixels.

For setup, see Install Aspose.Slides for .NET.

using System.Drawing;
using Aspose.Slides;
using Aspose.Slides.Export;

using var presentation = new Presentation();
presentation.SlideSize.SetSize(640, 360, SlideSizeScaleType.DoNotScale);
var slide = presentation.Slides[0];
var rectangle = slide.Shapes.AddAutoShape(ShapeType.Rectangle, 30, 30, 240, 100);
rectangle.FillFormat.FillType = FillType.Solid;
rectangle.FillFormat.SolidFillColor.Color = Color.Red;
rectangle.TextFrame.Text = "Hello";
presentation.Save("source.pptx", SaveFormat.Pptx);
using var thumbnail = slide.GetImage(0.25f, 0.25f);
thumbnail.Save("thumbnail.png", ImageFormat.Png);

FAQ

How is a thumbnail different from a slide image?

It uses the same slide-rendering workflow at a smaller size. Choose larger dimensions when you need a full-size image.

Can I create thumbnails smaller than the original slide?

Yes. Choose a smaller image size or scale factor. The example uses 0.25 for both axes, preserving the slide’s aspect ratio.

Can I render a thumbnail of one shape instead?

Yes. A shape can be rendered separately from the whole slide. See the slide image guide and choose the rendering bounds required by your gallery.