Nginx and Watermarking

I use ngx_http_image_filter_module module for servi开发者_StackOverflow社区ng images in my project. Everything works perfectly. And now I want to dynamically put watermarks on images.

I can't put them on upload because image sizes are often being changed. So, is that possible with nginx?

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Try this patch. I found it through internet.

It is allow to nginx to apply watermark's. This implementation only works with using function, which change size of image.