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Hiya Jonathan

I think my problem SHOULD be a relatively easy one to solve and I feel a little embarrassed at not being able to do so myself.

I capture videos from the telly either for posterity or for future viewing and in doing so I need to convert them if only to make their footprint smaller without any noticeable loss of quality.

Until now I've been quite successful but recently, for no reason that I understand I've had problems I can't seem to deal with.

Firstly the length of time this takes. I'm not that bothered whether a conversion takes half an hour or three hours except that it could indicate a more serious problem (and my own curiosity); I'm after quality, not speed.

More importantly though is the problem I'm having with the bitrate. As you know this is one of the features which has most impact on the resultant size of the file so try to use as small a bitrate as I can get away with. I use the H.264 codec which I think gives better results than most at lower bitrates and although I could tweak several of the settings I tend to leave everything at its default setting.

All this has been quite successful and I've been very happy with the quality at amazingly low bitrates, that is until now.

When converting nowadays I specify a bitrate and edit just a minute or two to evaluate the result, as I always do but I find it's  never the bitrate I've requested - it's always higher. I've several video converters I use and the same thing happens to all of them and I just can't explain it. This, together with the sometimes seven-fold increase in the time a video takes to convert really has me foxed.

All my drivers are up to date, I've done a stress test on the CPU, had Windows check my memory but I can't find what's happening (or not as the case may be).

It isn't only the problem I'm having but the reason for its sudden start.

I'm running Windows 7 32-bit, a Gigabyte GA-970A-UD3P mobo with an NVidia GeForce GTX 750 video card.

As far as I can remember I've neither added nor removed any hardware and very little software since everything worked well.

Are you able to at least point me in the right direction? I would be extremely grateful.

I leave you with my sincere gratitude for your time.

Hi Dave
I'm not really a Windows expert, and video compression is something of a dark art. But maybe I can help, given a little more detail:

1) What device are you using to capture from the TV?
2) What software are you using to convert/compress the video?
3) What sort of file size are you aiming for, for say a 2-hour movie, or a one-hour TV show?

Some preliminary thoughts:-

I recently used Adobe Media Encoder and was blown away by its speed and quality. Normally I use Mpeg Streamclip, but this was ten times faster on the same machine. Download a trial here: (You have to sign up for an Adobe ID, but it's probably worth the hassle).

When it comes to bitrate, some encoders will offer the option of a fixed bitrate or an average bitrate. If using the latter, doing a small section might not give an accurate reflection of the final bitrate of the video. A 2-pass encode will give better quality, but take twice as long.

Why the sudden slowdown? It could be something to do with having enough space on your drive, for the temp files to be written... I'm guessing here, but worth checking. Sometimes anti-virus software interferes with file-writes, checking every file that gets written, so try disabling AV for the time that you are encoding.

Sorry I can't be of more help. If you can answer the above questions, I may be able to give you more detailed feedback.

Regards, Jon  

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Jonathan H Pienaar


Professional Final Cut Pro HD editor, with some experience in DVD Studio Pro, Motion and Shake. Currently working mainly for South Africa's version of "60 Minutes" - "Carte Blanche". I have not yet made the transition to FCP X -- I'm waiting for the dust to settle on that, so in the meantime a good resource is Larry Jordan ( Please don't post questions about hooking up PVRs, DVDs and hi-fis - there must be an Expert in the Home Entertainment section who can help you better than I can.


20 years as a professional editor: worked in feature films, commercials, music videos and actuality.

High school, 2 years of university degree.

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