Encodings

RustVNC supports all standard RFB protocol encodings defined in RFC 6143.

Supported Encodings

Encoding	Type ID	Description	Best For
Raw	0	Uncompressed pixels	LAN, fallback
CopyRect	1	Copy screen regions	Scrolling, window moves
RRE	2	Rise-and-Run-length	Simple graphics
CoRRE	4	Compact RRE	Small rectangles
Hextile	5	16×16 tile-based	General purpose
Zlib	6	Zlib compression	High compression
Tight	7	Multi-mode adaptive	Universal (recommended)
ZlibHex	8	Zlib + Hextile	Alternative compression
ZRLE	16	Zlib Run-Length	Text, UI elements
ZYWRLE	17	Wavelet lossy	Low bandwidth
TightPng	-260	PNG compression	Lossless quality

Tight Encoding Modes

Tight encoding automatically selects the best compression mode:

Solid Fill - Single color rectangles (5 bytes)
Mono Rectangle - Two-color 1-bit bitmaps
Indexed Palette - 3-16 colors with palette
Zlib Compressed - Lossless RGB24 compression
JPEG - Lossy compression (requires turbojpeg feature)

Using rfb-encodings Directly

For custom implementations, use the encoding library directly:

use rfb_encodings::{Encoder, TightEncoder, PixelFormat};

let format = PixelFormat::rgba32();
let mut encoder = TightEncoder::new();

let encoded = encoder.encode(&pixels, width, height, &format)?;

Performance Characteristics

For a 1920×1080 full-screen update:

Encoding	Size	Compression Ratio	CPU Usage
Raw	8.3 MB	1:1	Minimal
CopyRect	8 bytes	∞:1	Minimal
Hextile	800 KB - 2 MB	4-10:1	Low
Tight JPEG	100-500 KB	16-83:1	Medium
ZRLE	400 KB - 1.5 MB	5-20:1	Medium
ZYWRLE	150-800 KB	10-55:1	High

TurboJPEG Feature

Enable hardware-accelerated JPEG compression:

[dependencies]
rustvncserver = { version = "2.0", features = ["turbojpeg"] }

Requires libjpeg-turbo installed on your system:

# Ubuntu/Debian
sudo apt-get install libturbojpeg0-dev

# macOS
brew install jpeg-turbo

# Windows
# Download from https://libjpeg-turbo.org/

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