Useful Utilities

Image Watermarker

Stamp a text or logo watermark on an uploaded image at a chosen corner or tiled across, with size and opacity controls, through ImageMagick.

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Image URL*A direct https link to an image file
Upload an image*Or paste a direct image link above; one of the two is needed
Watermark typeDefault Text mark
Watermark textThe line drawn as a text watermark; one line, long marks stay one lineDefault
Logo image uploadOnly used for logo marks; a transparent PNG works bestDefault
Watermark width (%)How wide the mark gets, as a percent of the image widthDefault 35
Text colourUsed for text marks; a logo keeps its own coloursDefault White
PositionWhere a single mark is placed; ignored when tilingDefault bottom right corner
Opacity (%)The mark covers this share of the picture; lower shows more of itDefault 40
Tile across the imageRepeat the mark as a pattern instead of one placementDefault false

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About Image Watermarker

The picture and the mark are composed in one ImageMagick run. A text mark is drawn as a single line on a transparent canvas at the point size that makes that line about as wide as you asked for, and the canvas is then trimmed to the text itself. A logo upload is used as it comes, only resized to the width you picked.

Opacity works on the mark's own alpha: the alpha channel is multiplied by your setting before anything is placed, so at 40% opacity the picture still reads through the mark at sixty percent. The mark is then composited over the image with the standard over operator anchored at the corner you chose — or, with tiling on, stamped repeatedly across the whole image instead.

The result is written back as a fresh PNG under a name built from your file; the original is left alone and nothing is cropped or rotated. If you uploaded instead of linking, the source never left your device.

Questions about Image Watermarker

Do I have to upload the picture, or can I paste a link?

Either works: a direct https link to an image is fetched first, otherwise upload the file straight from your device.

Why does a logo watermark need a transparent PNG?

The mark's own alpha drives its transparency. An opaque logo would cover the picture like a sticker, so a transparent background is what lets the photo read through around it.

How does the size setting work?

It is a percent of the image width: 35% of a 640 px image gives a 224 px mark. For text the point size is chosen to make the whole line about that wide; for a logo the image is scaled to that width.

Is the text rendered with a real font?

Whatever default font ImageMagick resolves in this build is used, so lettering can look slightly different on another server; the size and placement logic do not move.

Does a tiled mark line up with the edges?

The stamp repeats from the picture's edge inward; the final row and column are clipped at the edge, which is the ordinary way patterns tile.

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