ナレッジハブ・技術ガイド
画像・PDF透かし（ウォーターマーク）合成ツール
画像・PDF透かし（ウォーターマーク）合成ツール
本ツールは100%クライアントサイド（ブラウザ内）で動作します。写真、動画、音声、PDFファイルが外部サーバーにアップロードされることは一切なく、お使いの端末のメモリ内で安全に処理されます。
コアアーキテクチャ & 計算式
Watermarked Image = Base Layer (Image) + Compositing (Text Layer * Alpha Opacity)
The stamper calculates the diagonal hypotenuse of the image to perfectly center the text, applies a global alpha transparency (usually 30-50%), and permanently bakes the pixels into a new flattened file.
ベストプラクティスとガイドライン
- Use the Diagonal Pattern: Placing a small watermark in the bottom corner is useless, as thieves can easily crop it out. A repeating, 45 degree diagonal watermark across the center makes the image mathematically impossible to steal cleanly.
- Keep Opacity Subtle: A watermark should protect the image, not ruin it. Set the opacity between 20% and 40% so the underlying subject remains clearly visible to legitimate viewers.
- Use High Contrast Colors: A white watermark will disappear against a snowy background. Advanced watermarks often use a white font with a subtle black drop shadow to ensure legibility across both light and dark pixels.
よくある質問 (FAQ)
Can AI remove my watermark?
Unfortunately, yes. Modern Generative Fill AI can analyze surrounding pixels and erase simple watermarks in seconds. However, massive diagonal watermarks still require significant manual labor to remove convincingly.
Does watermarking reduce image quality?
Because the tool must re encode the original image to bake the text layer in, some slight JPEG compression generation loss will occur. Always keep your original unwatermarked files safe.
What is an invisible watermark?
Invisible (or steganographic) watermarking hides copyright data directly inside the mathematical noise of the pixels, invisible to the human eye but detectable via software. This tool generates standard visible watermarks.