What minimum bandwidth to send 4KHDR content via wifi? (possible with old wifi a/b?)

by camaronmars

Hello,

What is the minimum bandwidth needed for HEVC 4K HDR 10bits (of course 4:2:0, basically just for HDR 4K) ?

I have an entry level nas that usually via my router via wifi send data at max 6/7MB/s. I'm not sure I could use the nas (synology), with an android tv to read directly content from it.

I think not because even on my macbook pro, for some high bitrate movies (not 4K), reading over my nas can result in a bit of slutering (or feeling that the FPS are very very low).

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But maybe it's just because my macbook and not my nas? i guess not because my macbook play the same file well when copied to his internal ssd. Howe ever if you are aware of solution with android tv + nas via wifi, i'm interested. Maybe I need to put a SSD in the NAS (it use HDD), maybe I need a more powerful NAS, or even maybe i didn't understood well data needed and I need a better router with wifi ac (but doubt it since you guys say that you play smoothly 4KHDR10 movie from usb2 port of your android tv).

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Scientific data :

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So as far I understood, HEVC codec for 4K take maximum 8Mbps, which make exactly 1MB/s.

As far as understood, USB usually have speed like 20Mbps, that make more than 2MB/s.

As far as I understood, wifi a have similar speed to USB 2, so again more than 1.5MB/s sure.

My entry level Synology Nas (ds115j) is equiped with a NAS rated 500GB HDD, and connected to my router via ethernet. My router doesn't do Wifi .ac, but Wifi N 300mbps max I think.

Usually when I copy file from my Nas to my laptop via wifi, I have data speed transfer around 6MB/S or maybe more (not more than 8 I think).

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antiduh

Take a movie encoded with the settings you want to consider, divide its file size by its duration.

A 500 GB spinner hard drive can push about 60-80 Mbytes / sec when reading large files that are continuously allocated (which should be the case for media files).

USB links should not matter if you're connected via ethernet. USB 2.0 is 480 Mbit/sec, not 20 (that's USB 1.0). 480 Mbit/sec == 60 Mbyte/sec

Your Nas supports gigabit wired ethernet. 1 gbit/sec == 125 Mbyte/sec

Your router likely supports gigabit ethernet as well.

If you have a wifi N router, 300 Mbit is the max physical speed, which does not count overhead. 300 Mbit is 37.5 Mbyte. You'll likely get closer to 20 Mbyte /sec.

If you're only getting 6 Mbyte/sec over wifi, chances are you're using a wifi channel that is congested.

For a point of reference, I'm able to get 80 Mbyte/sec (640 Mbit/sec) over wifi in my house using an AC router and AC devices, and 5 GHz spectrum.

  • Consider upgrading your routers and devices to 802.11ac.
  • Make sure you're using the 5 GHz channels. 2.4 GHz channels are much smaller and tend to be more crowded.
  • Make sure your 5 GHz channel isn't being used by other nearby access points using a program like InSSIDer. Change which channel you're using if so. Your router should automatically sense this and change it for you, though.
  • If you have to share a wifi channel with another nearby access point, make sure they overlap perfectly. If they do, they share the channel intelligently (look up CSMA). If they don't, they look like noise to each other.
cingcacing

You need to test some scenario, like connecting the Android directly to NAS via ethernet using static IP addresses, then you'll know where's the bottleneck, either HDD/NAS read factor or transport layer

plexaddict

The 4k Material that I do have with Lossless audio has been between 50-75Mbps.

antiduh

Also, if you find out that your raw capacity numbers should be enough to handle the files you want to stream, but find that you're still stuttering, its possible that the stuttering is being caused by intermittent wifi interference. Try changing channels, etc.

elgenes

Wi-Fi is per definition UNSTABLE. If you usually get 6/7 MB/s while transferring data, you can't buy something on the basis that a device should be able to stream a video which requires 4 MB/s. Wi-Fi speeds go up and down, especially if you have neighbours with Wi-Fi, microwaves and whatnot. Another factor is that an Android TV device will not be placed where your PC is today. It could lover speeds and reliability. If you buy a Mi Box the antenna is probably not as good as your laptop antenna.

If you could do cable, then do it. If not, buy a AC router. I don't know how your house looks like, but if you have a stable Wi-Fi today, I am sure you can get the speed you need with a proper 5GHz AC router.

I stream torrents on my Mi Box. 4K HDR. Most movies are 15-25 GB in size.

And again; if you can do ethernet, then do it.