I was given several hundred EPUB files that are (needlessly) about 2-300MB in size. I find that I can use Calibre's pub editor to effectively compress each book by 80-90% by using lossy compression set to 60 while still remaining fully readable for my needs. However, it is quite tedious to individually:
- Open each file in the editor;
- Select "Tools|Compress images losslessly";
- Select the two "Enable Lossy Compression" checkboxes;;
- Click OK;
- Wait for compression to complete;
- Click Close on the compression results "Action Report" dialog box;
- Save the new compressed EPUB and close the editor.
Is there a plugin or action that would allow me to automate this so I can batch process all my files in one go?