Download/record slower than real time?

[nmyshkin]

Is it possible that a Livestream download (record with Livestreamer) could actually come down more slowly than real time?

I've made several unsuccessful attempts to record overnight operas broadcast on the Wisconsin Channel (PBS). I know my routines are working OK as I've checked for short intervals to see how things behave. But I keep missing the last hour or more of each recording. The video files are fine, just incomplete.

What I'm doing now it to start the download/recording about 2 minutes ahead of the broadcast. Then I have a second task scheduled about 15 min after the broadcast is scheduled to end which closes Livestreamer. Finally a third scheduled task shuts down the PC about 5 minutes later.

I just tried a 2 hour recording and watched the CMD window as the time was nearly up. Everything seemed to be fine but I only got about 1 hour and 14 minutes instead of 2 hours when the whole routine was done.

What gives?

[theewizard]

try again , start watching at 1 hr
you have glitch, recording stops before the final cmd

[nmyshkin]

I was hoping you were correct, but it seems to be even stranger.

I used Task Scheduler to start a recording at 6 pm but set up no end time. No errors showed up in the CMD window during the process and I stopped it manually at 2hrs 42 min.

Opened in WMP the file shows to be (and plays to) 1:46:00. The same happens with Kodi (which is how I would usually watch it).

Curious about this so I opened the file with Avidemux. It shows the length to be (surprise) 2:42:00.

So....something about the way I am just stopping the stream messes up the time index or something? Avidemux gave no complaints when opening the file. The worst thing about this now is that I threw away two opera recordings that perhaps could have been salvaged

Is there some way the stream is supposed to be terminated in Livestreamer other than by ^C or shutting down the process?

Now I need to see if I can do something with the file in Avidemux so it shows the proper time in the other programs.....

[aazerty]

Hi nmyshkin ,

The stream can have a name "aaa1" for 1h46 and "aaa2" for the rest !!!
In this case it is difficult to use Task Scheduler .

I think it is something like this .

Cheers .

[nmyshkin]

I fooled around with various tricks using Avidemux, trying to avoid the lengthy process of re-encoding. I chopped off the few minutes before the first I-frame and the bit after the last I-frame and tried a straight copy of the video and audio in the same container (MPEG TS). What I got was a black screen with no audio and no actual playing.

So...I finally gave up and re-encoded the video to mp4, without any trimming or worrying about key frames. I just copied the audio. The only other change, since I was going to do it, was to crop out the black mask in the video.

It took a long time to do but I ended up with a video with the correct time (2 hours 42 minutes), in-sync audio and no black mask. Too bad I trashed those supposedly incomplete opera files. I'm guessing there is something about the format of the TS stream or some issue with codecs, but neither WMP, VLC or Kodi will play them correctly as-is. Now I know. I can do the re-encoding overnight and have the machine shut down when it is done.

Problem "solved".

[theewizard]

at least you have a solution to the problem
record then recode

[ponens]

I'm guessing there is something about the format of the TS stream or some issue with codecs, but neither WMP, VLC or Kodi will play them correctly as-is.

maybe try using the hls source for the stream rather than the akamaihd source. but if you want to use the hls source unattended you'll probably need to use a script to pull the hls token from the webpage. if you want to stick with the akamaihd source, re-mux (w/o encoding) the finished file once through ffmpeg.