LabKit MATLAB Workbench

reference

Image API

Public API index | App guide

labkit.image.* provides GUI-free image file IO, conversion, preview sizing, and common enhancement operations. App-specific registration, measurement, ROI, matching, and export workflows build on these functions.

labkit.image.version() returns image-library version and compatibility information used by App definition.m requirement declarations.

Common Calls

filter = labkit.image.fileDialogFilter("IncludeAll", true);
paths = labkit.image.normalizePaths(rawPaths);
records = labkit.image.readFiles(paths);

source = labkit.image.im2double(records(1).image);
preview = labkit.image.ensureRgb(source);
preview = min(max(preview, 0), 1);
luma = labkit.image.rgb2gray(preview);
[preview, scale] = labkit.image.resizeToFit(preview, "MaxHeight", 1500);
[preview, budget] = labkit.image.previewBudget(preview, "MaxPixels", 1.2e6);

blurred = labkit.image.meanFilter2(preview(:, :, 1), 7);
enhanced = labkit.image.adjustBrightnessContrast(preview, 10, 20);
enhanced = labkit.image.localContrast(enhanced, 50, 3);
enhanced = labkit.image.sharpen(enhanced, 30, 1.5);
enhanced = labkit.image.grayWorldWhiteBalance(enhanced, 80, 0);

labkit.image.writeFile(enhanced, outputPath);

Normalization Helpers

labkit.image.im2double follows the MATLAB im2double call contract for supported numeric image classes, including the optional "indexed" mode.

labkit.image.rgb2gray follows the MATLAB rgb2gray call contract for RGB images and colormaps while using the documented Rec.601 luma transform.

labkit.image.ensureRgb changes channel shape only. It expands grayscale data to three channels or drops channels after RGB without changing class or sample values. Callers that need display-ready RGB data explicitly compose im2double, ensureRgb, and [0, 1] clamping as shown above.

Provided Operations

The module provides:

Applications add:

Use labkit.image.readFiles when an app needs generic source-image records. Apps may copy the returned path, name, and image fields into their own item structures. Specialized formats and result structures remain documented by the app that uses them.

Reference Contract

The generated Image API pages linked from the public API index document exact syntax, inputs, outputs, implemented options and defaults, legal values, failure behavior, examples, and related functions. In particular, resizeToFit accepts only the documented "bilinear" and "nearest" methods and rejects any other method instead of silently selecting an interpolation policy.

Functions And API

Open a function for exact MATLAB syntax, arguments, outputs, behavior, and source.

FunctionPurpose
labkit.image.adjustBrightnessContrastApply simple brightness and contrast adjustment.
labkit.image.ensureRgbReturn image data with exactly three color channels.
labkit.image.fileDialogFilterReturn a file-chooser-compatible image filter.
labkit.image.grayWorldWhiteBalanceApply generic gray-world white balance.
labkit.image.im2doubleConvert image data to double using MATLAB's im2double contract.
labkit.image.localContrastEnhance local value-channel contrast with a mean-filter mask.
labkit.image.meanFilter2Apply normalized 2-D mean filtering with edge correction.
labkit.image.normalizePathsNormalize image file path inputs to a string column.
labkit.image.previewBudgetDownsample image data to fit a display pixel budget.
labkit.image.readFilesRead image files into path/name/image records.
labkit.image.resizeToFitResize an image to fit within maximum row/column limits.
labkit.image.rgb2grayConvert RGB data using MATLAB's rgb2gray call contract.
labkit.image.sharpenApply generic unsharp-mask sharpening.
labkit.image.versionReturn the LabKit image facade contract version.
labkit.image.writeFileWrite one image file, creating the parent folder when needed.

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