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README.md

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 # Image actions
+
+Image actions will automatically compress jpeg and png images in Github Pull Requests.
+
+- **Compression is fast, efficient and lossless**
+- Uses mozjpeg + libvips, the best image compression available
+- Runs in Github Actions **for free**
+
+![Preview of image-actions pull request comment](https://user-images.githubusercontent.com/924/62024579-e1470d00-b218-11e9-8655-693ea42ba0f7.png)
+
+## How to add this to your repository:
+
+- Add the following steps to a workflow file found at: `.github/main.workflow` (If you don’t have one, create it.)
+- Paste in the following:
+
+```workflow
+workflow "Compress images" {
+  resolves = ["calibreapp/image-actions"]
+  on = "pull_request"
+}
+
+action "calibreapp/image-actions" {
+  uses = "calibreapp/image-actions@master"
+  secrets = ["GITHUB_TOKEN"]
+}
+```
+
+This action requires a `GITHUB_TOKEN` so that it has access to commit the optimised images to your repository.
+
+## Links and resources
+
+- [View calibre/image-actions on the Github Marketplace](https://github.com/marketplace/actions/calibreapp-image-actions)
+- [Mozjpeg](https://github.com/mozilla/mozjpeg)