Chromecast from web client transcoding options?

[wolfbuddy 16]

Hi,

 

There are quality options for playback in the web client while a video is playing, and there is a bitrate option in the Android app for Chromecast playback, but how is this controlled when casting from the web client? I can only get the much lower quality videos to play back smoothly on the Chromecast, almost as if they're not transcoding at all.

 

BTW, I'm using a Linux server but I wasn't sure where to put questions relating to the web client.

 

Cheers

Edited December 17, 2014 by wolfbuddy

[Sp3kt3r 13]

As per my understanding the quality control when you cast from web client is under the preference tab, web client. The quality setting for web client is what Chromecast will use. I don't have issue with transcoding to Chromecast. What is your issue when you your say "play back smoothly". Are you referring to buffer ? Perhaps WiFi not fast enough ?.

Edited December 17, 2014 by Sp3kt3r

[wolfbuddy 16]

It is as if it is buffering, but looking at the server LAN adapter's network utilization it is streaming in waves.

 

I've been able to get it playing smoothly by setting the max bitrate down low to 1Mbps, but I'm not convinced that the wifi link to the Chromecast is limited to that. Also the server LAN is reporting peaks of 5Mbps so I'm wondering if it's more related to what the hardware is capable of.

 

Is there a way of determining what the weak link is when transcoding like this?

[JeremyFr79 228]

I've had no transcoding issues with my 2 Chromecast's.  Transcoding usually finishes less than halfway through playback and I believe I'm streaming as high as you can to the CC's over my WiFi.  I guess I should say though that I use an enterprise class AP with 4 watts of output lol

[wolfbuddy 16]

I'm fairly sure that it's the hardware in my server that is the issue as the problem gets worse with the higher the quality of the source file.

 

I've got various specs of machines so I will install the server on them to try and prove exactly where the issue is.

[Sp3kt3r 13]

What is your current spec ?

[wolfbuddy 16]

Atom D525 with 2GB DDR3.

Edited December 19, 2014 by wolfbuddy

[wolfbuddy 16]

Wow. I now understand how CPU intensive MBS is, and not just when transcoding. 

 

A library scan is surprisingly heavy on the CPU, as is the difference a faster CPU in the server makes to the library browsing experience at the client.

 

I was thinking before that it probably just needs GPU accelerated transcoding support, but that wouldn't be enough. If I decide to stick with MB3 as my media delivery system of choice, I'll need to build a server with a fairly high spec CPU to get the most out of it. Relative to a server that's just delivering file access of course.

 

Additionally, there's quite a difference on the server side load depending on the device that it is streaming to. At the same max bitrate setting, the load is greater if it is transcoding to the chromecast over playing back in the web app, so the web app needs separate options like the Android app has.

[ebr 14902]

When we do a library scan, we are running ffprobe on your media which is probably almost as intensive as transcoding (but for a shorter period).  But as you surmised, we are doing much more than just delivering files so, depending on your exact requirements, media formats and clients, we will require more power than just a file server.

[Sp3kt3r 13]

Atom D525 with 2GB DDR3.

I would also use a different computer, this CPU is only 2 core which might be fine for 720p transcoding but depending on the quality settings you will have problem for 1080p transcoding. I also recommend at least 4gig of ram depending on your OS and other service that are running in background.

[wolfbuddy 16]

Running on the bare Ubuntu Server Edition, 2GB appears to be fine for now and it's easy to drop more sticks in. It's all about CPU grunt, and that will mean more threads too when you add more clients.

 

When we do a library scan, we are running ffprobe on your media which is probably almost as intensive as transcoding (but for a shorter period).  But as you surmised, we are doing much more than just delivering files so, depending on your exact requirements, media formats and clients, we will require more power than just a file server.

 

I think I'm going to change the MB in my server and drop an i3 Haswell in it. I've been testing transcoding with MBS running on a Celeron machine and it's working fine.............but, the CPU is running flat out on both cores delivering 1080p content to just one client. There's no additional headroom there for more clients plus the work that it has to do as a file server.

 

But it's a bit more complicated than that. File servers, by their very nature, are running 24/7 so it's not like you can just throw the fastest CPU you can buy at it because that would just mean more power used. It will just become a larger and noisier machine too. I reckon the i3 is a good balance of low power usage at idle, where the server will spend most of it's life, and the clock speed and threads for intensive media delivery.

Edited December 21, 2014 by wolfbuddy