Plex Profiles, Specifically Chromecast and an "Augmented profile"

General Discussions
1

Hi all,

I’m seeing a problem when trying to play video over multiple Chromecasts. From the logs I can see that, when a file begins playing, it loads an “Augmented Profile”. I’d like to know more about Profiles in general within Plex, how they are loaded and matched against a device. Here are a few questions:

  • How are profiles loaded?
  • How can I tell if profiles are being picked up correctly?
  • What determines a match between a device and a profile?
  • What is an “Augmented Profile” and how is it created?

I think I’m able to answer one of my own questions. From trying to debug the Chromecast page that Plex loads, it seems that an “Augmented Profile” is the native capabilities of that device.

Fingers crossed someone from the Plex dev team can give me some insight into this. I’ve posted on the Plex discord group as well but had little help as of yet.

An example of the augmented profile log:

[Chromecast] [MDE] Augmented profile:
{
  "directPlay": {
    "mp4": {
      "mimeType": "video/mp4; codecs=\"avc1.42E01E\"",
      "video": {
        "codecs": {
          "h264": {
            
          }
        },
        "maxBitDepth": 8,
        "maxFrameRate": 60,
        "maxLevel": 42,
        "maxWidth": 1920,
        "maxHeight": 1080
      },
      "audio": {
        "codecs": {
          "aac": {
            "maxSamplingRate": 48000
          },
          "mp3": {
            
          }
        }
      }
    },
    "mkv": {
      "mimeType": "video/webm",
      "video": {
        "codecs": {
          "h264": {
            
          },
          "vp8": {
            
          }
        },
        "maxBitDepth": 8,
        "maxFrameRate": 60,
        "maxLevel": 42,
        "maxWidth": 1920,
        "maxHeight": 1080
      },
      "audio": {
        "codecs": {
          "aac": {
            
          },
          "mp3": {
            
          },
          "vorbis": {
            "maxChannels": 2
          }
        }
      }
    }
  },
  "directStream": {
    "video": {
      "codecs": {
        "h264": {
          
        }
      },
      "maxBitDepth": 8,
      "maxLevel": 42,
      "maxWidth": 1920,
      "maxHeight": 1080
    },
    "audio": {
      "codecs": {
        "mp3": {
          
        },
        "aac": {
          
        },
        "opus": {
          
        }
      },
      "maxChannels": 6
    }
  }
}
2

TL;DR make sure the settings on the device you are casting from is set to original. The Chromecast will use the casting devices quality settings

I figured out what was causing my initial problem, so I will explain the issue and solution in case anyone else runs into the same problem…

The initial problem was that we had 2 Chromecasts on 2 different TVs and the same file would direct play on one Chromecast but then transcode when played on the other. I searched through the logs to try and understand why this was and could see that the Chromecast would load an “augmented profile” instead of the Chromecast.xml profile that is the Resources folder of Plex. The augmented profile that was being used had set the maxResolution to SD, meaning that the video would begin transcoding.

Turns out, my girlfriend was casting from her Android device to one TV, and I was casting to the other from my Android device. The difference was that she hadn’t changed the “Quality over WiFi” setting to original within the Android application. It appears the Chromecast uses the quality settings from the devices that casts it and not the best quality settings available for the Chromecast (which I had assumed it would).

I have no idea if this is common knowledge or common sense, but 3 days of investigating lead me to this conclusion. I also tested the theory by casting from the web player after changing the quality settings and it’s the same behaviour. FML!

Also, to try and answer my own questions:

How are profiles loaded?
No idea

How can I tell if profiles are being picked up correctly?
You can see in the Plex Media Server.log file if a profile is being used

What determines a match between a device and a profile?
■■■■ knows

What is an “Augmented Profile” and how is it created?
I believe an “augmented profile” is the profile that casting devices sends to the Chromecast/server so that it can decide if the file needs to be transcoded

mic drop

3

Would be awesome to get some insights in how plex matches between profiles and devices and how to add another profile for a specific device.

Currently plex uses the same android.xml profile for a brand new SHIELD and every stupid android phone out there.