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Linda Harding
not low enough data rate
on Mar 17, 2011 at 4:48:05 pm

I am editing a video for an overseas festival. These are the specs.


MPG2 File Encoding Standards
For submission to Cannes Lions 2011 please encode a high quality video as an MPG2 Program Stream. The resulting MPG2 file should have Audio and Video as one file, encoded as Pal 25fps, Frame Size 720 x 576. The Data Rate must not exceed more than 1 megabyte/s. Please do NOT send DVD, Windows Media Video, QuickTime or other file formats.


Compressor's lowest data rate is 2.4. Does anyone know a program that can output less that 1 megabyte/s?


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Craig Seeman
Re: not low enough data rate
on Mar 17, 2011 at 6:09:07 pm

MegaBYTE or MegaBIT. Big difference.
1 megabyte is 8 megabits. Compressor is expressing in megabits.



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Linda Harding
Re: not low enough data rate
on Mar 17, 2011 at 6:29:46 pm

I figured it was something like that.
Thank you.
Sorry for the brain fart.


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Craig Seeman
Re: not low enough data rate
on Mar 17, 2011 at 6:39:25 pm

It can be frustrating when clients still express data rates in bytes. Years back there was lots of inconsistency with this between compression apps but these days every program I know of expresses in bits.



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Morris Ku
Re: not low enough data rate
on Mar 21, 2011 at 12:00:19 pm

i am working some videos to enter this festival too....

in compressor, the lowest average Bit Rate that i can adjust is 10.0Mbps, and the maximum bit rate is 12.0Mbps, so actually i can't really use Compressor to do it...

so is there any method/software that can help?

thanks!


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Craig Seeman
Re: not low enough data rate
on Mar 21, 2011 at 2:33:53 pm

Sorry but you provide no explanation as to what you're trying to do and from your description you are likely very wrong. There's no circumstance I know of that causes Compressor to have a lowest data rate of 10Mbps. Instead claiming Compressor doesn't do something how about explaining what you're doing and asking for the best way to do it.



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Morris Ku
Re: not low enough data rate
on Mar 22, 2011 at 3:01:29 am

Sorry Let me explain a little bit more...

the video that i need to encode would be as follows, a MPG2 Program Stream Video file that The Data Rate must not exceed more than 1 megabyte/s

MPG2 File Encoding Standards
For submission to Cannes Lions 2011 please encode a high quality video as an MPG2 Program Stream. The resulting MPG2 file should have Audio and Video as one file, encoded as Pal 25fps, Frame Size 720 x 576. The Data Rate must not exceed more than 1 megabyte/s. Please do NOT send DVD, Windows Media Video, QuickTime or other file formats.

So i try to use Compressor to help, so i choose the MPEG-2 Program Stream setting, and then in the "Encoder" tab you can adjust the video "Quality", so i try to lower all the attributes to fit the requirement. That is, i set the Average Bit Rate to 10.0Mbps and Maximum Bit Rate to 12Mbps. And i use one of my video to test, and put it to Final Cut Pro. and it shows the video Data Rate is around 1.2 megabyte/s, which exceed the requirement.....

so can i do anything to make the data rate a little bit lower in Compressor to get the MPG2 video?

or any other method/software that can help?

thanks again!


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Craig Seeman
Re: not low enough data rate
on Mar 22, 2011 at 3:30:55 pm

Megabyte and Megabit are not the same.
1 Megabyte is 8 Megabits
Compressor MPEG2 Program Stream allows you to set the average down to 2 Megabits which is well below 8 Megabits.

If you read my first post on March 17 I explained the difference between Megabyte and Megabit. Linda understood it and despite that you repeated the same mistake. Please read the thread before posting to it.



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Marcos Frutig
Re: not low enough data rate (VBR or CBR)
on Mar 29, 2011 at 7:54:09 am

Hi guys,

I am in a same job as Linda and I'd like to know wether is better to use VBR ou CBR and 1 or 2 passes in this case.
Bearing in mind the following specs: (MPG2 Program Stream. The resulting MPG2 file should have Audio and Video as one file, encoded as Pal 25fps, Frame Size 720 x 576).
I tried read in to threads reggarding CBR and VBR but only found forums dated 2007, so I felt safer asking in a fresh one.

Thanks a lot!


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Craig Seeman
Re: not low enough data rate (VBR or CBR)
on Mar 29, 2011 at 3:29:40 pm

For this kind of delivery I'd use CBR (two pass if possible). The reason is I want the entire encode to be at or near the maximum bit rate. VBR is much better for efficient encoding but since the maximum bit rate is defined you may as well give every frame the maximum bits. I do this for all my TV Spot delivery with the same reasoning.



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Marcos Frutig
Re: not low enough data rate (VBR or CBR)
on Mar 29, 2011 at 6:34:36 pm

Tks a lot Craig!


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