Supported Formats
Open Screen currently supports two primary export formats:MP4 Video
MP4 is the recommended format for high-quality video exports with the best compression and compatibility. Technical Specifications:- Codec: H.264 (AVC) with hardware acceleration when available
- Container: MP4 with fast-start optimization
- Color Space: BT.709 with sRGB transfer (IEC 61966-2-1)
- Encoding: Variable bitrate (VBR) for optimal quality/size ratio
- Hardware Acceleration: Automatically uses GPU encoding when available
Open Screen automatically detects if your system supports hardware-accelerated encoding. If not available, it falls back to software encoding.
GIF Animation
GIF format is perfect for creating animated loops that can be shared on social media and messaging platforms. Technical Specifications:- Encoding: Floyd-Steinberg dithering for optimal color quality
- Workers: Multi-threaded encoding (4 workers) for faster processing
- Quality: High-quality palette generation (quality level 10)
- Transparency: Not supported (black background)
Aspect Ratios
Open Screen supports all common aspect ratios for modern video content:| Aspect Ratio | Common Use Case | Example Dimensions |
|---|---|---|
| 16:9 | YouTube, standard video | 1920×1080, 2560×1440, 3840×2160 |
| 9:16 | TikTok, Instagram Stories | 1080×1920 |
| 1:1 | Instagram feed, social posts | 1080×1080 |
| 4:3 | Classic video format | 1440×1080 |
| 4:5 | Instagram portrait | 1080×1350 |
| 16:10 | Widescreen displays | 1920×1200 |
| 10:16 | Vertical widescreen | 1200×1920 |
The aspect ratio is independent of the export format. You can export any aspect ratio as either MP4 or GIF.
MP4 Quality Settings
MP4 exports offer three quality presets to balance file size and visual quality.- Source Quality
- Good Quality
- Medium Quality
Best for: Archival, professional use, further editing
- Exports at the original source resolution
- Maximum bitrate based on resolution
- No downscaling applied
- Largest file size
- 4K (3840×2160): 45 Mbps base
- QHD (2560×1440): 28 Mbps base
- 1080p and below: 18 Mbps base
At 60fps, bitrates are increased by 1.7× for smoother motion.
GIF Settings
Frame Rate Options
Control the smoothness and file size of your GIF exports:| Frame Rate | Label | Best For | File Size |
|---|---|---|---|
| 15 FPS | Balanced | General use, smaller files | Smallest |
| 20 FPS | Smooth | Social media, good quality | Small |
| 25 FPS | Very smooth | High-quality animations | Medium |
| 30 FPS | Maximum | Premium quality, smooth motion | Largest |
Higher frame rates create smoother animations but significantly increase file size and export time.
Size Presets
GIF exports can be scaled to different resolutions:Medium (720p)
Medium (720p)
- Maximum height: 720 pixels
- Width calculated to preserve aspect ratio
- Best for social media sharing
- Balanced quality and file size
Large (1080p)
Large (1080p)
- Maximum height: 1080 pixels
- Width calculated to preserve aspect ratio
- High quality for larger displays
- Larger file sizes
Original
Original
- No downscaling applied
- Uses source resolution
- Maximum quality
- Largest file sizes (can be very large)
Loop Settings
GIFs can be configured to loop infinitely or play once:- Infinite Loop (default): GIF repeats continuously
- Play Once: GIF plays through once and stops
Resolution Guidelines
Open Screen automatically calculates optimal export dimensions based on your settings:Dimension Requirements
Maximum Resolutions
The app supports exporting up to 4K resolution:- Maximum width: 3840 pixels
- Maximum height: 2160 pixels
- Maximum total pixels: 8,294,400 (4K)
For aspect ratios that would exceed codec limits at source resolution, Open Screen automatically scales down while preserving quality.
Performance Considerations
MP4 Exports
- Hardware acceleration: Uses GPU encoding when available for 2-5× faster exports
- Parallel processing: Video encoding and muxing happen in parallel
- Queue optimization: Maintains optimal encoder queue (120 frames) for throughput
- Color space: Full-range RGB with BT.709 primaries for accurate colors
GIF Exports
- Multi-threaded: Uses 4 worker threads for faster encoding
- Two-phase process:
- Frame extraction and rendering (shows percentage progress)
- GIF compilation (shows “Compiling…” with render progress)
- Memory intensive: Large GIFs may require significant RAM
GIF compilation can take several minutes for longer videos. The progress indicator will show “Compiling GIF” during the final phase.
Best Practices
- For sharing on YouTube/Vimeo: Use MP4 at Source or Good quality, 16:9 aspect ratio
- For social media (Twitter/X): Use MP4 at Good quality with appropriate aspect ratio
- For Instagram Stories: Use 9:16 aspect ratio at Good quality
- For animated previews: Use GIF at 15-20 FPS, Medium size preset
- For high-quality loops: Use GIF at 25-30 FPS, Large or Original preset
MP4 files are typically 10-50× smaller than equivalent GIFs while maintaining better quality. Use GIF only when you need platform compatibility or transparent loops.