Image Watermark Adder
Stamp copyright text or logo watermarks across images with 9-point grid alignment, diagonal rotation, and tiled repeating grids.
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What is Image Watermark Adder?
Watermarking digital photography and marketing graphics protects copyright ownership and deters unauthorized image reuse. Our Image Watermark Adder places customizable text or logo overlays onto images with 9-point anchor alignment, diagonal rotation, opacity controls, and tiled repeating pattern options directly in browser memory.
Designed for accuracy, speed, and privacy, this tool runs entirely on your local device with zero network latency.
How to Use the Image Watermark Adder
- 1Upload your base image file (JPG, PNG, or WebP) from your computer.
- 2Choose your watermark type: "Text Watermark" (custom text, font, size, bold, color) or "Logo Watermark" (upload secondary image logo).
- 3Select an anchor position (Top-Left, Center, Bottom-Right, etc.) or enable the "Tiled Pattern" grid overlay.
- 4Adjust Opacity and Rotation sliders, preview the composited result, and download your protected image.
Formula & Calculation Logic
Applies 2D canvas coordinate translation and rotational matrix transforms (ctx.translate, ctx.rotate) before drawing alpha-blended vector text or raster logo overlays.
Canvas Alpha Composite: ctx.globalAlpha = opacityFactor; ctx.drawImage(...) or ctx.fillText(...)Image Watermark Adder Frequently Asked Questions
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