Watermark

imgproxy supports the watermarking of processed images using another image.

Specifying watermark image

There are three ways to specify a watermark image using environment variables:

• IMGPROXY_WATERMARK_PATH: the path to the locally stored image

• IMGPROXY_WATERMARK_URL: the watermark image URL

• IMGPROXY_WATERMARK_DATA: Base64-encoded image data. You can easily calculate it with the following snippet:

  base64 tmp/watermark.webp | tr -d '\n'`.

You can also specify the base opacity of a watermark using the IMGPROXY_WATERMARK_OPACITY environment variable.

info

If you're going to use the scale argument of watermark, it's highly recommended to use SVG, WebP or JPEG watermarks since these formats support scale-on-load.

Watermarking an image

Use the watermark processing option to put a watermark on a processed image:

watermark:%opacity:%position:%x_offset:%y_offset:%scale
wm:%opacity:%position:%x_offset:%y_offset:%scale

The available arguments are:

• opacity - watermark opacity modifier. The final opacity is calculated as base_opacity * opacity.
• position - (optional) specifies the position of the watermark. Available values:
  • ce: (default) center
  • no: north (top edge)
  • so: south (bottom edge)
  • ea: east (right edge)
  • we: west (left edge)
  • noea: north-east (top-right corner)
  • nowe: north-west (top-left corner)
  • soea: south-east (bottom-right corner)
  • sowe: south-west (bottom-left corner)
  • re: repeat and tile the watermark to fill the entire image
• x_offset, y_offset - (optional) specify watermark offset by X and Y axes. When using re position, these values define the spacing between the tiles.
• scale - (optional) a floating point number that defines the watermark size relative to the resulting image size. When set to 0 or omitted, the watermark size won't be changed.

Custom watermarks pro

You can use a custom watermark by specifying its URL with the watermark_url processing option:

watermark_url:%url
wmu:%url

The value of url should be the Base64-encoded URL of the custom watermark.

By default, imgproxy caches 256 custom watermarks with an adaptive replacement cache (ARC). You can change the cache size using the IMGPROXY_WATERMARKS_CACHE_SIZE environment variable. When IMGPROXY_WATERMARKS_CACHE_SIZE is set to 0, the cache is disabled.

Text watermarks pro

You can put a text as a watermark on your image with the watermark_text processing option:

watermark_text:%text
wmt:%text

The value of text should be the URL-safe Base64-encoded text of the custom watermark.

By default, the text color is black and the font is sans 16. You can use Pango markup in the text value to change the style.

If you want to use a custom font, you need to put it in /usr/share/fonts inside a container.