Image Options

Open this dialog from Options → Image Option or with the Ctrl+I shortcut. It applies visual adjustments to the currently displayed image, with a live preview directly on the canvas. The adjustments only change how the image looks — they never alter your labels.

Adjustments

Adjustment	Range	Default	Description
Invert Colors	on / off	off	Invert the colours of the image (photographic negative).
Grayscale	on / off	off	Convert the image to grayscale.
Brightness	`-100` – `100`	0	Make the image brighter or darker.
Contrast	`0` – `200`	100	Adjust the difference between light and dark areas (100 = original).
Gamma	`10` – `300`	100	Adjust the gamma curve, brightening or darkening mid-tones (100 = neutral).
RGB Channel Levels	`-100` – `100` per channel	0	Boost or cut the Red, Green and Blue channels individually.
Hue shift	`-180` – `180`°	0	Rotate the colours around the colour wheel.
Saturation	`0` – `300`	100	Adjust colour intensity (100 = original, 0 = grayscale).
Value shift	`-100` – `100`	0	Shift the brightness (value) component of the colours.
Sharpen / Blur	`-10` – `10`	0	Negative values blur the image, positive values sharpen it (0 = original).

Color Replacement

Enable Color replacement to swap one colour for another:

Pick a Source Color and a Target Color.
Set a Tolerance (0 – 100) to control how close a pixel’s colour must be to the source to be replaced.
Click Add Color Replacement. Each rule is listed and can be removed with Clear All Replacements.

Several replacement rules can be combined.

Presets

The current set of adjustments can be reused across images:

Save Preset — store the current settings as a named .json file.
Load Preset — apply a previously saved preset.
Manage Presets — open the presets folder in your file explorer.

Applying changes

OK — apply the adjustments to the displayed image.
Cancel — discard the adjustments and restore the original image.
Reset — reset every adjustment back to its default value.