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H.264 Pro-Recorder + Media Express 2.4 (win) CPU usage

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Richard Freemantle
H.264 Pro-Recorder + Media Express 2.4 (win) CPU usage
on Jul 15, 2011 at 4:36:41 pm

I bought the H.264 Pro-Recorder purely for the hardware encoding, so that I could record the output of my graphics card at 1920x1080p with minimal CPU overhead. Allowing me to create smooth hq video tutorials for my cpu/gpu intensive software.

Unfortunately, recording with Media Express 2.4 maxes out my CPU! I assume this is because the h264 stream is being previewed.
Looking at the running processes I notice the streaming server is only using about 4% cpu, which is what I'd expect. Even when minimised & the preview isnt visible the cpu use is huge, so I also assume the stream is still being decoded.

If the preview is indeed the source of the CPU overhead, will Media Express 3 allow the preview to be turned off?

Any update to when the new windows beta will be released?

Also, with current PC 8.1 drivers/Media Express 2.4 I cannot record @60Hz (30Hz works ok), will this be fixed in the new release?

Thanks
Rich


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Jack Welten
Re: H.264 Pro-Recorder + Media Express 2.4 (win) CPU usage
on Jul 15, 2011 at 6:36:30 pm

Hello Rich,

this is confirmed by the last sentence of this post http://forums.creativecow.net/readpost/124/876832

would be a great feature to switch off the preview, maybe then the Pro Recorder also could be used with a netbook (with low resolution 1024x600),


regards,

Jack


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Richard Freemantle
Re: H.264 Pro-Recorder + Media Express 2.4 (win) CPU usage
on Jul 15, 2011 at 8:38:25 pm

Hi Jack,

I read that post but was still surprised at the preview cpu overhead in Media Express (2.4). Im not on the newest hardware (quadcore intel core2 9450 @2.66ghz) but vlc can playback the stream using ~23% cpu usage, whearas the Media Express preview couldnt keep up & cpu was at 96%

Anyway, fingers crossed the 'preview off' feature is implemented in the new version (or will be). It certainly would make the Pro Recorder useful in lots of scenarios!

Rich


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Mark Brunkhart
Re: H.264 Pro-Recorder + Media Express 2.4 (win) CPU usage
on Aug 4, 2011 at 11:16:46 pm

We experienced the same 100% CPU issue using fairly modern Core 2 Duo's with video preview. This led to very glitchy results when the CPU attempted to do even minor tasks. Typical H.264 decoding using ffdshow on the same machine also exhibited much lower CPU usage similar to your description, so it seems the software decoding being done in Media Express is somewhat inefficient.

Also, very important...you get much better performance with an NVIDIA card where much of the decoding can be done on the card. We swapped in a GeForce 310, and dropped CPU usage dramatically (although still surprisingly high for just streaming data from the device to the disk). This might be a solution for you rather than upgrading the machine.

I am in agreement that some type of 'no preview' or 'low quality preview' would help particularly during capture, or better yet, a more efficient H.264 decoder would help a lot.


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Richard Freemantle
Re: H.264 Pro-Recorder + Media Express 2.4 (win) CPU usage
on Aug 5, 2011 at 6:49:05 pm

Thanks for the tip re the graphics card. Im currently on an NVidia 9800gtx+, so maybe a newer card would help.
OTOH Hopefully someone from BMD will actually read & respond to my queries before Im forced to upgrade my graphics card in the hope of turning my H.264 Pro-Recorder into something more than an expensive paperweight!

Rather annoyingly, in my usage case I get better performance using free screen recording software!


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