Problem reproducing live stream

1

Hello,

I am doing tests reproducing a live video. I have used my own web page and also the “Live” page in api.video dashboard and in both this problem occurs.

By using developer tools of Chrome, I realized that from time to time, a 404 error is produced. Here an example of a normal video chunk, that returns 200 status code:

https://live.api.video/li2hfn95uQCBw85cTmPzcjFr_480p/index.m3u8

In that case, the content type returned is application/vnd.apple.mpegurl which is right. It also has an ETAG as 5f7cc3a4-130a

Following to the above chunk, the exact same link returns a 404 error:

https://live.api.video/li2hfn95uQCBw85cTmPzcjFr_480p/index.m3u8

In this case, the content type returned is text/html which is clearly wrong. And it also does not have an ETAG header.

And following above, other links returned 404 error also. For example, this:

https://live.api.video/li2hfn95uQCBw85cTmPzcjFr_1080p/index.m3u8

Look at the name. It contains 1080p instead of 480p as before.

that behaviour persists some other chunks, then, other kind of links are retrieved:

https://s.ns1p.net/?v=1592857685&a=isrtzw
https://embed.api.video/l.gif?t=3p36et
etc…
https://b.ns1p.net/?v=1592857685&x=ktehb9&r=isrtzw,1xtwrfw,13bzyad:i5k,9pdy,7b,7a,-1|i5k,9pld,70,70,-1|i5k,9psh,74,73!isrtzw,aaz5yv,13bzyad:i5k,9pdz,6s|i5k,9pkx,6x|i5k,9prx,6w
etc…

After other several links, again m3u8 files are received. The most strange thing is that the streaming never got interrupted.

What is going on with that?

Thanks
Jaime

2

Now we dig into the weeds a bit Jaime :smiley:

The m3u8 file is a manifest file, it lists the next segments or chunks for the player to download and play. Here is an example (that I just streamed):

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-MEDIA-SEQUENCE:91
#EXT-X-TARGETDURATION:2
#EXTINF:2.000,
1602018434128.ts
#EXTINF:2.000,
1602018436041.ts
#EXTINF:2.000,
1602018438046.ts

There are 3 segments listed here. Let’s look at the first one:
#EXTINF:2.000,
1602018434128.ts
EXTINF is saying the next chunk is 2 seconds long. The next line is the file to download to play those 2 seconds of video.

The manifest above has 3 chunks listed. That’s 6 seconds of video that that player “knows what to do with.”

If the next m3u8 fails, its ok, the player still has a few seconds of video before it needs the next…

The 480p to 1080p - These are the different encodings we are creating for you. In this case, the player is jumping from 480p to 1080p.

The other files - those are analytics firing in the player so that the results can be reported back to api.video.

Summary: the manifest file tells the player about the next 3 chunks of video. That means there is 6 seconds of video that is playable. The next manifest should arrive before the last chunk finishes playing (so that chunks 4, 5, 6, etc. can be identified), but a small hiccup does not affect playback.

Doug