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High cpu usage in VLC v.2.1.1 Rincewind (outdated)

This is not a blog, it is just a “no-indexed” webpage with the purpose of informing the VLC development team about high cpu usage on certain streams. As an example, we have picked one particular stream URL out of the master.m3u8 file of NRK, the national broadcaster in Norway. Here are the technical details.

The urls are encrypted and changed on a daily basis. An updated master.m3u8 file is found here: NRK1 Master.m3u8, and here is an url example working just today:

https://nrk1us-f.akamaihd.net/i/nrk1us_0@102847/index_1428_av-b.m3u8?sd=10&rebase=on&e=1&id=AgBPoRaJUacmZarJiVITEGcJvmTtsKDdmLKTkF8MO59bxGgj5QxmXrYNYE4AT0OIyF2E5YWKlg3XNQ%3d%3d

Note: When you select the “url of the day” after downloading the master.m3u8, then look to this example above as to which substring toextract from the file master.m3u8, because each string is longer!

The Major concern with this stream decoding, probably related to h.264 (?), is the cpu load. Sometimes but not always when the stream is paused cpu keeps on at 52% on a 2.5GHz Toshiba dual core cpu. At other times the cpu starts out in less than 30 % Cpu for some seconds, then suddenly moves up to apporx 75% cpu (active). The cpu usage should have been less than 30% when the stream is active.

This error is only present on our Windows laptops, not on Mac OS X (as far as we have been able to validate). This error has been there for a long time; a couple of years. Our guess is that it is related to h264 decoding.

I can be contacted and can do tests and other things to assist in any way possible.

VLC CPU High 181113

 

This bug effectively prevents us from using VLC for this type of streams. Such a shame for such an excellent product.

Hope this is helpful in detecting and correcting the error.

Best regards

Carl Henrik