Implementing Text Overlays in Video Projects¶

Introduction to Text Overlays¶

Text overlays are essential components in professional video editing. They allow you to add titles, subtitles, watermarks, captions, and other important text elements to your videos. With the Video Edit SDK for .NET, you can create sophisticated text overlays with precise control over appearance, positioning, and timing.

Key Features and Capabilities¶

The SDK provides extensive customization options for text overlays, including:

Custom font selection from system-installed fonts
Complete control over font size, weight, and style
Flexible color options for both text and background
Precise positioning with multiple alignment options
Timing control to set when text appears and disappears
Transparency and opacity settings

Implementation Example¶

The following code demonstrates how to create and configure a text overlay in your .NET application:

// Initialize the VideoEditCoreX object (assumed to be already created)
// var videoEdit = new VideoEditCoreX();

// Create a new text overlay object with your desired text
var textOverlay = new VisioForge.Core.Types.X.VideoEdit.TextOverlay("Hello world!");

// Set when the text should appear and for how long
// This example: text appears 2 seconds into the video and stays for 5 seconds
textOverlay.Start = TimeSpan.FromMilliseconds(2000);
textOverlay.Duration = TimeSpan.FromMilliseconds(5000);

// Define the position of the text on the video frame
// X and Y coordinates are measured in pixels from the top-left corner
textOverlay.X = 50;
textOverlay.Y = 50;

// Configure font properties for the text
textOverlay.FontFamily = "Arial";  // Set the font family
textOverlay.FontSize = 40;         // Set the font size in points
textOverlay.FontWidth = SkiaSharp.SKFontStyleWidth.Normal;   // Normal width characters
textOverlay.FontSlant = SkiaSharp.SKFontStyleSlant.Italic;   // Apply italic style
textOverlay.FontWeight = SkiaSharp.SKFontStyleWeight.Bold;   // Apply bold weight

// Set the text color to red
textOverlay.Color = SkiaSharp.SKColors.Red;

// Set a transparent background behind the text
// You could use any color with alpha channel for semi-transparency
textOverlay.BackgroundColor = SkiaSharp.SKColors.Transparent;

// Add the configured text overlay to your video project
videoEdit.Video_TextOverlays.Add(textOverlay);

Positioning Options¶

The SDK uses the X and Y coordinates for absolute positioning. X and Y represent pixel coordinates from the top-left corner of the video frame:

// Position text at specific coordinates (in pixels)
textOverlay.X = 50;   // Horizontal position from left edge
textOverlay.Y = 50;   // Vertical position from top edge

// You can also position text in other areas:
// Bottom-right corner (assuming 1920x1080 video):
// textOverlay.X = 1820;  // 1920 - 100 for some margin
// textOverlay.Y = 980;   // 1080 - 100 for some margin

// Centered (assuming 1920x1080 video and measuring text size):
// textOverlay.X = 960;   // Half of video width
// textOverlay.Y = 540;   // Half of video height

Working with Fonts¶

The SDK leverages the SkiaSharp library for powerful text rendering capabilities. This provides access to all system fonts and advanced typography features.

Retrieving Available Font Families¶

You can dynamically retrieve the list of fonts available on the current system:

// Get all available fonts on the current system
// This is useful for creating font selection dropdowns in your UI
var availableFonts = videoEdit.Fonts;

// You can now iterate through the fonts or bind them to a UI control
foreach (var font in availableFonts)
{
    // Use the font information as needed
    Console.WriteLine(font);
}

Advanced Styling Techniques¶

For more sophisticated text effects, consider combining text overlays with other SDK features:

Apply animation effects to make text move across the screen
Use multiple text overlays with different timing for sequential display
Combine with shape overlays to create text boxes with custom backgrounds
Integrate with video transitions for dynamic text entry and exit effects

Development Resources¶

For more code examples and advanced implementation techniques, visit our GitHub repository containing comprehensive .NET SDK samples.