使用encoding.com golang包装器

I'm rather new to both golang and encoding.com and I'm trying to use the encoding.com API wrapper to transcode a simple video file, but I'm rather confused by the format to use.

When looking at the tests I can see how to call the AddMedia function (https://github.com/nytimes/encoding-wrapper/blob/master/encodingcom/media_test.go#L9-L39) but unfortunately it doesn't work for me.

package main

import ("github.com/NYTimes/encoding-wrapper/encodingcom")

func main() {
  client, err := encodingcom.NewClient("https://manage.encoding.com", "123", "key")

  format := encodingcom.Format{
      Output:       []string{"https://key:secret@bucket.s3.amazonaws.com/aladin.ogg"},
      VideoCodec:   "libtheora",
      AudioCodec:   "libvorbis",
      Bitrate:      "400k",
      AudioBitrate: "64k",     
  }

  addMediaResponse, err := client.AddMedia([]string{"https://samples.mplayerhq.hu/h264/Aladin.mpg"},
        []encodingcom.Format{format}, "us-east-1")
  }
}

The error "raised" is

APIError.Errors.Errors0: Output format 'https://key:secret@bucket.s3.amazonaws.com/aladin.aac' is not allowed! (format #0)
APIError.Message:

and I really don't get it, the Output element in the Format looks missplaced, am I reading the test wrong? Using the API builder the format parameter should receive only the format, for example "ogg", and there's a "destination" parameter for S3. It also doesn't specify if the url must be urlencoded, but honestly I don't think so. Still keys and secrets can contain for example the char '/'

Any more experienced gopher?