About "Chromatic Glass - Web Edition"

Chromatic Glass helps people with color vision deficiency (protan, deutan, and tritan types) tell colors apart more easily. It changes colors of the camera image or of an image file in real time. It changes only the necessary parts, keeping the original colors as much as possible, so that colors that are hard to tell apart look clearly different. This is a web application coded with HTML5 + JavaScript, based on the smartphone edition of "Chromatic Glass", and it works without installing any software if there is a corresponding web browser.

Please see the "Chromatic Glass" Web Site and Kazunori Asada Web Site for details of the method and color vision terms.

Three Modes
Distinguish Color
Makes colors that people of the P, D, and T types tend to confuse easier to tell apart. The app builds "color zones" along the confusion lines (lines connecting confused colors), and changes the colors in the zone into the most distinguishable ones, keeping the original colors as much as possible. Zones and changes are calculated in a perceptually uniform color space (CIELUV). The changed image is shown alternately with the original image, so the changed parts look as if they blink (0.33 seconds changed, 0.5 seconds original). This is the mode when you open the page for the first time.
Find Color
Changes only the colors close to the cursor color, or to one of the basic 11 colors, so you can find similar colors in the image. "Close" ignores the difference in brightness and uses closeness of hue (the distance is measured in u'v' chromaticity).
Simulation
Calculates how people of the P, D, and T color vision types may see colors, and shows it to people with common color vision (type C). It helps to understand which colors are hard to distinguish.
Buttons at the Top
Settings
Opens the Settings screen.
Simulation
Shows the image changed in Distinguish Color or Find Color as it may appear for the simulation color vision type and strength.
Chromaticity Diagram
Shows an xy or u'v' chromaticity diagram at the lower left. Choose which in Settings. The small ring on the diagram is the position of the color under the cursor.
Color Name
Shows the name of the color under the cursor (the color name pop-up). In browsers that do not support WebAssembly (WasmGC), this button is not shown.
Freeze
Stops the video. Press again to resume. Unavailable for image files.
Save
Saves the currently displayed image, after the color change, as a JPEG.
File / Camera
The left button opens a file (still picture). The right button returns to the camera (video) while a file is shown; while the camera is shown and the device has more than one camera, it switches to the next camera.
Mirror / Rotation
Mirror flips the image horizontally. Rotation turns it 90 degrees clockwise at a time.
Zoom (x100% - x500%)
Digital zoom. At 100% the image fills the screen without gray margins.
The Bottom Bar and Operations
Mode tabs (at the bottom)
Switch among Distinguish Color, Find Color and Simulation (the page opens in the mode you used last).
Zone range slider (Distinguish Color)
Sets the range of colors to change. It has two thumbs, left and right; hold the part between them (blue) to move the whole range. The far left (0.0) is the side containing green, and the far right (1.0) is the side containing red (for type T, blue on the left and green on the right). Double-click (double-tap) to turn the range on and off.
Color change slider and color vision type
Opened and closed with the right "▲". Move the thumb inside the circle. The distance from the center is the variation (0.0 to 0.5), and the clockwise angle from the top is the direction (0.0 to 1.0). Double-click (double-tap) the thumb to turn Boost Mode (a strong change) on and off (not in Find Color). Choose the color vision type (P, D, or T) with the vertical selector beside the circle.
Presets
Stores the parameters of Distinguish Color (the zone, the strength and direction of the color change, and the five switches) as a set. You can keep up to eight sets. Open the menu with the left "▲" and choose one to load its parameters. Press and hold an item for about two seconds to save the current parameters to it. You can also edit the names and values in "Preset Parameters" in Settings, and restore the initial values.
Searching radius slider and basic 11 colors (Find Color)
Sets how far from the color to search. A small value finds only close colors, and a large one also finds different colors. Click (tap) one of the basic 11 colors on the lower bar (achromatic, red, yellow-red, yellow, yellow-green, green, blue-green, blue, purple-blue, purple, red-purple), or choose it from the left "▲" menu, to search for that color.
Color vision type and strength (Simulation)
Choose the color vision type (C, P, D, or T). C shows the original image. The strength slider is 0.0 for no simulation and 1.0 for full simulation. It does not simulate anomalous trichromacy (mild color vision deficiency).
Image operations
Click (tap) to move the cursor. Double-click (double-tap) returns the zoom, the position and the cursor to the initial state. While a file is shown or the video is frozen, drag moves the image. The mouse wheel zooms by a constant ratio per step. A trackpad pinch or a two-finger pinch zooms in and out (up to x500%). Press and hold the video for one second to freeze it (this can be turned off in Settings). After 10 seconds without operation, the texts disappear except the cursor, the color name pop-up, the chromaticity diagram and the basic 11 colors ribbon; click (tap) to show them again.
Color Names (Color Cursor)

Turn on "Color Name" at the top (or "Show Color Name" in Settings) to show the cursor and the name of the color under it in the original image. Choose the content of the four lines in Settings (JIS systematic and traditional color names, ISCC-NBS systematic names, TCCA traditional names, CIELAB, Oklab, CIELUV, RGB, XYZ, xyY, Munsell, or none). The color under the cursor is a weighted average over about 5 by 5 pixels (Gaussian filter). Values and names assume the image is in sRGB under a D65 light source, and follow the standards, but they are not necessarily accurate. It works only in browsers that support WebAssembly (WasmGC).

Settings

In Settings you can choose whether to embed texts (the mode and parameters) in saved images, press-and-hold to freeze, the color name display and its four lines, the color changing options (Auto Color Zone, Reverse Color Zone, Inversion on Both Sides, Keep Achromatic Zone, Boost Mode), Zone allocation, the chromaticity diagram (xy / u'v'), the language, the color space, the preset settings, and reset. Settings are saved in this browser.

Images changed by this software and simulated images are calculated with specific methods and conditions, and do not necessarily represent how colors actually look. Please use them as a guide. Colors are changed by dividing colors along the confusion lines and changing them in a perceptually uniform color space (CIELUV). The simulation is based on the method of Brettel, Viénot and Mollon (Journal of the Optical Society of America A, vol.14, no.10, 1997).

A web browser which supports WebGL 2 is required. The web camera only works when WebRTC is supported and the page is opened over HTTPS.

Licenses

This software uses the font below. The full text of the license follows.

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