You may POST an array of files to https://upload.propkill.net/upload, by default you will get a JSON response. If you want a response in something else than JSON, you can add a flag to specify the format you want. For example, https://upload.propkill.net/upload?output=csv. Valid response types are: json, csv, text, html, and gyazo.
curl -i -F files[]=@yourfile.jpeg https://upload.propkill.net/upload