An image refers to a visual element (such as a picture, icon, or graphic) used to enhance the user interface (UI) and improve the user experience (UX). Images can be used for branding, navigation, buttons, backgrounds, and illustrations.
Types of Images
1. Raster Images (Bitmap Images)
- Made of pixels and have a fixed resolution.
- Quality decreases when scaled up.
- Common formats: PNG, JPEG, WEBP, BMP, GIF
- Example: Photos, UI icons, and backgrounds.
2. Vector Images
- Made of mathematical paths (lines and curves).
- Scalable without losing quality.
- Common formats: SVG, PDF, AI (Adobe Illustrator), EPS
- Example: Logos, icons, illustrations.
3. Nine-Patch Images (Android-specific)
- Special PNG images that stretch dynamically.
- Used for buttons, backgrounds, and UI elements in Android.
4. Animated Images
- Moving images for better UI interaction.
- Formats: GIF (simple animations), WebP (optimized animation), Lottie (JSON-based vector animation)
- Example: Loading indicators, animated stickers.
5. Drawable Images (Android-specific)
- XML-based graphics used in Jetpack Compose and XML layouts.
- Example: Shape Drawables (buttons, borders), Layer Drawables, State List Drawables (for different button states).
6. Remote Images
- Images loaded from the internet using APIs.
- Example: Images from Firebase, Unsplash API.
- Libraries: Glide, Coil (for Jetpack Compose), Picasso.
How to Choose the Right Image Type
For icons and logos: Use SVG (vector) for scalability.
For high-quality photos: Use JPEG (compressed) or PNG (transparent backgrounds).
For animations: Use Lottie (vector) or WebP (optimized GIF alternative).
For app backgrounds: Use WebP (better compression and quality).