Last date modified: 2026-Jun-16
Native imaging - dithering algorithm options
Relativity native imaging offers multiple dithering algorithms you can apply when imaging your documents. Use the comparison tables below to evaluate image size and quality across algorithm types for text-rich and image-rich documents.
Dithering algorithm details
When configuring native imaging, system admins can select from eight dithering algorithms:
Consider grouping the eight options under four algorithm families and providing a one-sentence description of each family, for example:
- Clustered 6x6, 8x8, 16x16 — groups pixels into clusters. Larger cluster sizes produce smaller file sizes but lower image detail.
- Dispersed 4x4, 8x8, 16x16 — disperses pixels across a matrix pattern. Produces a finer, more even grain than clustered dithering.
- Floyd & Steinberg — diffuses the difference between a pixel's color value and its quantized equivalent to neighboring pixels. Produces high-quality results for image-rich documents.
- Threshold — compares each pixel value against a fixed threshold (0–255). Values above the threshold convert to black; values below convert to white. Requires a threshold value in the Dithering Threshold field.If you select Threshold, you must also enter a value (0–255) in the Dithering Threshold field. The recommended default is 128.
Dithering results for text-rich documents
The following table shows dithering results for text-rich documents. Each image in the table shows a document sample magnified to 150% to illustrate visual differences between algorithms. All samples are 300 DPI, black and white.
| Image dithering type | Size | Image sample magnified (150% scale) |
|---|---|---|
| Clustered 6x6 | 27 KB |
|
| Clustered 8x8 | 25 KB |
|
| Clustered 16x16 | 23 KB |
|
| Floyd & Steinberg | 24 KB |
|
| Dispersed 4x4 | 24 KB |
|
| Dispersed 8x8 | 24 KB |
|
| Dispersed 16x16 | 24 KB |
|
| Threshold 0 | 2 KB |
|
| Threshold 127 | 22 KB |
|
| Threshold 215 | 22 KB |
|
| Threshold 255 | 22 KB |
|
Dithering results for image-rich documents
The following table shows dithering results for image-rich documents. Each image in the table shows a document sample magnified to 150% to illustrate visual differences between algorithms. All samples are 300 DPI, black and white.
| Image dithering type | Size | Image sample magnified (150% scale) |
|---|---|---|
| Clustered 6x6 | 45 KB |
|
| Clustered 8x8 | 39 KB |
|
| Clustered 16x16 | 33 KB |
|
| Floyd & Steinberg | 70 KB |
|
| Dispersed 4x4 | 64 KB |
|
| Dispersed 8x8 | 52 KB |
|
| Dispersed 16x16 | 69 KB |
|
| Threshold 0 | 2 KB |
|
| Threshold 127 | 79 KB |
|
| Threshold 215 | 27 KB |
|
| Threshold 255 | 20 KB |
|