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手寫筆跡增強

漂白黃斑暗光影背景,對藍/黑手寫筆跡和紅印章進行高斯局部對比度拉伸。

上傳手寫簽名、蓋章或合同拍攝照片

採用高級局部對比度直方圖增強(CLAHE)算法。將手機拍攝照片中發黃、黴斑陰影背景強效漂白,加粗加濃藍/黑色簽字筆鋒和紅色印章。

關於此工具

The Handwriting Ink Contrast Booster is a savior for digitizing signed agreements and historical manuscript archives.

Scans of hand-signed documents often look dull due to grey scanner glass reflection, yellow paper tint, or faded ink. Re-printing or photocopying these files results in blurry, illegible signatures. Traditional contrast tools darken the entire background, worsening the layout.

This tool utilizes **Contrast Limited Adaptive Histogram Equalization (CLAHE) and hue-based color separation**. In a secure local Canvas process, it isolates handwriting strokes (both black and blue) from background parchment, bleaches shadow wrinkles completely, and infuses faded inks with deep, saturated contrast, leaving your documents looking incredibly crisp and clean.

使用方法

  1. Import hand-signed document

    Provide a PDF containing faded signatures, handwritten diaries, or sketches.

  2. Configure ink filter

    Select the color profile to isolate (e.g. blue ink, black ink, or both) and adjust sharpening.

  3. Sharpen and download

    Click execute to trace colors with a radar scanner effect and download purified PDF.

使用場景

Executed Contracts Repair

Repair poorly scanned agreements, sharpening signatures and bleaching paper background to A4-pure white.

Handwritten Manuscripts Archive

Digitize written journals or diaries, extracting clear black strokes while erasing age-related stains.

Historical Ledger Restoration

Restore faint ink details on aged archival ledgers, rescuing valuable handwritten coordinates.

常見問題

How does this differ from normal grayscale conversion?

Grayscale converts paper shadows into gray values. Our adaptive algorithm separates background luminance and isolates signature "ink spectrums," purifying the backdrop to absolute white while leaving stroke edges sharp.

Will I lose handwriting stroke texture?

No. The CLAHE algorithm works on a sub-pixel level, preserving natural pen-stroke pressure, ink fading, and dynamic line weights.

Can I keep red corporate stamp marks?

Yes. By enabling "Chroma Ink Preservation," the booster whitens paper background and darkens writing, while maintaining the bright colors of red seals and blue ink signatures.

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Security

  • Client-side processingFiles never leave your device
  • No file uploads100% private & secure

Compliance

GDPR Compliant
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