LucadenFree online toolsBrowse toolsPrivate image effect
Increase or reduce image contrast locally with a full negative-to-positive control and a downloadable PNG result.
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How it works
Important
Keep an untouched copy of important source files. Browser processing depends on available device memory, and you should inspect every downloaded result before deleting the original.
Practical details
Increase or reduce image contrast locally with a full negative-to-positive control and a downloadable PNG result.
High contrast can erase subtle tones and low contrast can make text or edges difficult to see. Review actual use size and accessibility needs.
Lucaden adds a focused workflow, conservative memory limits, before-and-after preview, privacy checks, and exact attribution.
Questions
No. Browser Canvas decodes and exports the image in memory, while the pinned Jimp effect modules change its pixels locally.
High contrast can erase subtle tones and low contrast can make text or edges difficult to see. Review actual use size and accessibility needs.
Jimp 1.6.1 (MIT) performs the deterministic pixel operation; the browser's Canvas API performs PNG export. The upstream project retains its name, copyright, and license.
Open-source foundations
Lucaden documents its standards sources, architectural references, and permissive runtime dependencies while keeping this workspace consistent with the Lucaden interface.