Introduction
Multimedia combines text, images, audio, video, and animation into a single interactive presentation.
This chapter covers the common file formats for each media type and the fundamental difference between
vector and raster graphics.
Elements of Multimedia
| Element | Description |
|---|
| Text | Written characters/words |
| Graphics/Images | Static visual content |
| Audio | Sound content |
| Video | Moving visual content with sound |
| Animation | Simulated movement of static images/graphics |
Vector vs Raster Graphics
| Feature | Vector Graphics | Raster (Bitmap) Graphics |
|---|
| Composition | Made of mathematical paths (lines, curves, shapes) | Made of a grid of individual pixels |
| Scalability | Can be resized infinitely without quality loss | Loses quality (becomes blurry/pixelated) when enlarged |
| Best For | Logos, icons, illustrations | Photographs, detailed realistic images |
| File Formats | SVG, AI, EPS | JPEG, PNG, BMP, GIF |
| Software Examples | CorelDRAW, Adobe Illustrator | Adobe Photoshop, MS Paint |
📌 Key Test: Zoom in repeatedly — a vector image stays crisp at any zoom level; a raster image eventually shows visible square pixels ("pixelation").
Image File Formats
| Format | Key Feature |
|---|
| JPEG/JPG | Compressed (lossy), widely used for photographs; smaller file size |
| PNG | Lossless compression, supports transparency; good for graphics/logos |
| GIF | Supports simple animation, limited colour palette (256 colours) |
| BMP | Uncompressed (or minimally compressed), large file size, high quality |
| SVG | Scalable Vector Graphics — vector format for web-based graphics |
Audio File Formats
| Format | Key Feature |
|---|
| MP3 | Compressed (lossy), widely used, small file size |
| WAV | Uncompressed, high quality, large file size |
| AAC | Compressed, generally better quality than MP3 at similar file sizes |
Video File Formats
| Format | Key Feature |
|---|
| MP4 | Most widely used, good compression-to-quality ratio |
| AVI | Older format, larger file sizes, high compatibility |
| MKV | Open-standard container supporting multiple audio/subtitle tracks |
Lossy vs Lossless Compression
| Type | Description | Example Format |
|---|
| Lossy | Reduces file size by permanently discarding some data — some quality loss | JPEG, MP3 |
| Lossless | Reduces file size while preserving all original data perfectly | PNG, WAV, ZIP |
✅ UPSC/SSC Focus: Vector vs raster graphics distinction (scalability is the key test) · Image format-specific features (JPEG-lossy, PNG-transparency, GIF-animation) · Lossy vs lossless compression trade-off · Common audio/video format recognition.