Sandbox quality

Hello i have a simple question. I’am developing my site in react.js and using In my test i’am using the sandbox and tried to watch a 4k video. The quality is really bad and could the sandbox be the cause? Does it change with a paid plan ? Thanks to all

Hi, your video is encoded @ 4K in the sandbox. But our video player will only deliver the appropriate size for your screen & network connection.
For your video in question - it was encoded last night as 4k:

What do you mean by “bad quality” Can you clarify? If you are using a browser, can you look in devTools and see the size of the video being downloaded? (the video chunks are .ts files, and the quality is in the filename)


Thank you Doug for your reply. It’s like it is sending me the 240p, but i never had connection problems. My computer resolution is in 1080p now and always works fine in streaming with 1080p quality on youtube for example or netflix. So i don’t know why i see in 240p now. This problem occurs only in HLS mode, if i reach the .mp4 link it’s all ok.

OK, Let’s diagnose. I’m looking at the video with ID vi5SjTifBkXcpXL55Kj34Mhx:

The encode times are GMT:

Your post was ~11:30 GMT, so I’m going to assume that the 4K was not ready yet (it finished at 11:28), but that 240-1080p streams were ready to playback. So you should have seen the 1080p for sure.

what do you see in devtools. If you open up chrome devtools, you can see the .ts files being downloaded, and the filename will tell you the size of the video being played back.

When I test on my machine, I am seeing the 720p video playback.

(I cant see the file names in this screenshot of devTools, so here is a closeup)

Are you seeing the same?


Hi doug,
first of all thanks for your reply.

I am not seeing what you see, because the video chuck as you can see in the attach are 480p

NOTE: I have a 1Gbps connection which has no problem with video streaming in 4k

There are 2 parts of streaming - one is the network connection - which is certainly not your issue. The 2nd part is how big the video is on your screen. If the video on the page is only 850x480, that’s the size of the video you’ll get. I have a 4k screen as well, but if I make the video super small, I only get the 240p video streamed to my browser :slight_smile:

Can you verify the size of the viewport that the video appears in on your screen?


hi doug I have a MacBook Pro M1 which resolution is 2560×1600 at 227 pixel
obviously I streamed in full screen to do the test that I reported to you,

furthermore the same issue happen to a my colleague which monitor is 1080p

you can check all here: MacBook Pro 13-inch - Technical Specifications - Apple

Are you starting at the smaller size, and then when you increase the size, it is not changing? Which browser/version are you using?
I’ll run this past the player team.


I’am using the latest Safari version 14.0.3, i started in full screen. But the same problem occurs with chrome too and firefox but only in HLS, the .mp4 is good.

Your video has disappeared (since it is in the sandbox), but it appears that the resizing fails when the video is silent.

Would you mind retesting with a video that has audio (and meanwhile, we’ll fix the silent audio resizing issue?)


Hi Doug, it seems working now with sound. We let you know if something will change, as always thank you for your support. We have other different questions so we’ll open another post, thank you again.

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