How to reduce webapp loading time

[pirole]

So the counter is counting the data transcribed, not the data received by the browser, right?

If the player started playing as soon as the counter starts it would shave the waiting time by more than that, more than half, almost as good as the other apps.

I will try around with ffmpeg.

[sub]

The playback in the browser require transcoding, and it does it to HLS, which is widely supported, but wont start playback until there is at least couple of segments available.

If you use a native player, like NextPVR.exe or yauiclient or kodi etc, you'll get substantially quicker video startup and channel change time.

[pirole]

Yes, I know about the trancription but now I'm confused. Is this a limitation of the browser that won't start playing until it has 2 segments or ffmpeg that requires a buffer to start encoding?

According to firefox cache, the page first requests service?method=channel.transcode.status&format=json multiple times while the counter is increasing. Then requests the m3u8, after that the first segment and playback starts immediately. Cannot say if it starts before receiving the segment entirely or not because it all happens very fast.

Is it a ffmpeg limitation that the m3u8 can only be sent after the segment is complete instead of flushing it as it is being produced?

[sub]

ffmpeg will only write the segments to the m3u8 when they're complete.

Browser will only start playback when a couple of segments are in the m3u8 url.

NextPVR's web app doesn't attempt to start the playback too early, because players don't typically like empty playlists.

In theory I could trim a few seconds off, but probably not much. When viewing in the web app, and requiring transcoding, you're probably never get it any faster than you get in that uiclient.html page. That uses ffmpeg's low latency startup modes etc, rather than segmented HLS.

[sub]

On the uiclient.html page, with the Hauppauge tuner I currently have plugged in, video typically starts in about 4 seconds. Changing channels typically takes about 3 seconds. If the channels are on the same frequency, sometimes the channel change time can be as low as about 1.0-1.5 seconds.

Ultimately how quick your tuner is, and your CPU, also factors into this.

[pirole]

Ok, so it's a ffmpeg limitation.

I was curious why you keep referring to the uiclient and checked it out more closely. Does it do the transcription via javascript? Uau. If yes, nice work but I don't notice a loading speed difference. The fans speed however start to drown out the audio.

If ffmpeg support was as good as it is here I would suggest to add the option to create the m3u8 first and start outputting the segment immediately after. I cut one of them in half and it played ok and going by the headers there is a good chance it is playable as it is being produced.

[pirole]

Just read your second message. Yes, my computer is old.

[mvallevand]

Upload your zipped logs, it is very clear in there where any bottlenecks are.

Martin

[sub]

I'll make the HLS playback start a bit quicker for the next release. There are some small improvements I can make in there.

[pirole]

Thank you Martin, it isn't that important.

Thank you sub.