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12 minutes in 10Mb: Is it even possible?

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Brecht Wouters
12 minutes in 10Mb: Is it even possible?
on Jun 11, 2009 at 2:14:09 pm

Hi all,

A client wants to have a video with a duration of 12 minutes resized to only 10Mb for download purposes. I guess their netwerk might have restraints in terms of file sizes. Preferably a wmv.

I'm asking myself: can it be done at an acceptable quality? The clip has text in it, so it has to be readable. I've made a muxed mpeg in Mpeg Streamclip, which is appr. 550Mb in size. I've put that through Procoder3, but I don't think that quality is acceptable.

My question is: Can it even be done? With which program? Is there another codec besides wmv that I can recommend for this purpose?

I already have Procoder 3 on a Windows system and Compressor on an Apple system. I've also got Sorenson Squeeze on windows. How should I go about this?

Regards and thanks in advance.


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Andrew Saliga
Re: 12 minutes in 10Mb: Is it even possible?
on Jun 11, 2009 at 3:12:34 pm

Brecht,

That sounds like quite the challenge. I mostly use Compressor and sometimes Sorenson, but I'd recommend outputting an H.264 QuickTime file. Also, I wonder what you could do in Sorenson if you encode an FLV?

Compression is all about compromise. I'm assuming this video has audio as well. If it's primarily speech you can lower the bitrate and sampling rate more than you could with a music video or similar content.

Also change your frame size, this will make a large difference.

How much motion is in the clip? If it's a relatively static shot/edit drop the framerate a little.

-Andrew Saliga

Steelehouse Productions
http://www.steelehouse.com


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Daniel Low
Re: 12 minutes in 10Mb: Is it even possible?
on Jun 11, 2009 at 3:45:32 pm

[Brecht Wouters] "A client wants to have a video with a duration of 12 minutes resized to only 10Mb"

10 Megabits (Mb) or 10 MegaBytes (MB)?

With or without audio?

I'll assume MB. The datarate limit is rather low for any text to be clear. You could try H.263 or MPEG-4 or even the sorenson 3 codec at a frame size of 160x120 at a rate of about 120kbits/s









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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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Andrew Saliga
Re: 12 minutes in 10Mb: Is it even possible?
on Jun 11, 2009 at 3:46:46 pm

I don't want to hijack this thread, but Daniel, you wouldn't recommend an H.264? I thought it gives better results than H.263, at least as far as file size to quality ratio is concerned.

I'm definitely not disagreeing, just looking for a reason to cite.

-Andrew Saliga

Steelehouse Productions
http://www.steelehouse.com


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Daniel Low
Re: 12 minutes in 10Mb: Is it even possible?
on Jun 11, 2009 at 4:22:08 pm

[Andrew Saliga] "but Daniel, you wouldn't recommend an H.264"

Not at such low datarates - it's worth trying though.



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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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Rich Rubasch
Re: 12 minutes in 10Mb: Is it even possible?
on Jun 11, 2009 at 11:09:05 pm

I would make sure what codec they prefer. I would also recommend running the datarate at 10 frames per second. Audio is mono for sure. I would probably go WMV and keep the frame size pretty small, around 192 x 144 or maybe one size up.

In any case it's gonna be a tiny window. I would also work on a 1 minute chunk and do some tests then measure the file size by 12.

Oh, and if they are thinking they are clever keeping to to 10 megs because it can be emailed, they will actually have to hit closer to 7 megs because once an email app encodes it for delivery it blows up about 2 megs.

Rich Rubasch
Tilt Media



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Daniel Low
Re: 12 minutes in 10Mb: Is it even possible?
on Jun 12, 2009 at 9:19:36 am

[Rich Rubasch] "I would also recommend running the datarate at 10 frames per second"

I've always found that reducing the frame rate has such an adverse effect on spatial and temporal quality that it's not worth it for the slight reduction in datarate that can be achieved. Modern codecs are designed to work best at full frame rates, if this was being delivered by RTSP then maybe there' be more benefit but I doubt it. Even in the early days of delivery to mobile devices I'd nearly always do full frame rate.
You'll also encounter problems if you're dealing with text like subtitles when reducing the frame rate.

[Rich Rubasch] "I would also work on a 1 minute chunk and do some tests then measure the file size by 12."

Not a good idea if you are using VBR!



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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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Brecht Wouters
Re: 12 minutes in 10Mb: Is it even possible?
on Jun 17, 2009 at 10:50:11 am

The solution presented itself: the client allowed to output it in 50Mbs, which worked out fine.

Thanks all!


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