Parameters

There are two groups: the ones visible in the left panel, and the jitter settings folded away under "More".

What jitter is for

Handwriting looks handwritten because no two characters are identical. The backend adds a small random offset to every character, drawn from a normal distribution — the "sigma" parameters control the width of that distribution. Bigger means messier; 0 means perfectly regular. The defaults are already tuned to look natural, so don't change them all at once.

Basic parameters

Parameter	Default	Meaning
Font Size	124	Character size in pixels. Bigger text means fewer characters per sheet.
Line Spacing	200	Baseline-to-baseline distance. Must exceed the font size or lines will overlap.
Top Margin	50	Distance from the text block to the top edge.
Bottom Margin	50	Distance to the bottom edge.
Left Margin	50	Distance to the left edge.
Right Margin	50	Distance to the right edge; >>> right-alignment measures from here too.
Word Spacing	1	Extra gap between characters.
Width	2481	Paper width. Mutually exclusive with a background image.
Height	3507	Paper height. Mutually exclusive with a background image.

2481 × 3507 is A4 at 300 DPI, and the defaults are sized around A4.

Toggles

Parameter	Default	Meaning
Add underline	on	Draws a rule under every line. Also decides whether auto-generated paper is ruled.
Auto-adjust English spacing	off	Widens the gaps between English words so they don't run together. Irrelevant for Chinese.

Jitter (under "More")

Parameter	Default	Meaning
Line Spacing Sigma	0	Variation in line spacing. Off by default.
Font Size Sigma	2	Variation in character size.
Word Spacing Sigma	2	Variation in the gap between characters.
Perturb X Sigma	3	Variation in each character's horizontal position.
Perturb Y Sigma	3	Variation in each character's vertical position.
Perturb Theta Sigma	0.05	Variation in each character's rotation, in radians.
Ink depth sigma	30	Variation in ink darkness, simulating heavier and lighter strokes.

Strikethroughs

Use these to leave a few "crossed out" marks on the page.

Parameter	Default	Meaning
Probability of a strikethrough occurring	0.005	Chance that any given character gets struck through.
Width of strikethrough	8	Thickness of the line.
Standard deviation of the strikethrough length	2	Variation in line length.
Standard deviation of the strikethrough width	2	Variation in line thickness.
Standard deviation of the strikethrough angle	2	Variation in line tilt.

Built-in preset

The "Built-in Preset" dropdown applies a complete tuned parameter set.

Small with underlines (Yunyan) — small text in the Yunyan font, generous line spacing and margins, with underlines:

Parameter	Preset	(Default for comparison)
Font Size	70	124
Line Spacing	100	200
All four margins	150	50
Font Size Sigma	1	2
Line Spacing Sigma	1	0
Word Spacing	2	1
Perturb X Sigma	1	3
Perturb Y Sigma	1	3
Probability of a strikethrough occurring	0	0.005
Add underline	on	on

The preset has two requirements: the 云烟体.ttf font must be available, and there must be no background image set. If either is unmet it tells you rather than failing quietly.

Tuning tips

• Characters are colliding → raise Line Spacing or Word Spacing.
• Looks too tidy to be handwriting → raise Perturb X Sigma and Perturb Y Sigma.
• Looks too chaotic → lower Perturb Theta Sigma first; it affects the impression the most.
• Want to fit more per page → lower Font Size and Line Spacing, or shrink the paper.
• Changed a parameter and nothing happened → you have to click "Preview Handwrite Image" again. The preview does not re-render on its own.