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MPEG2 bitrate??

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Ali Krauth
MPEG2 bitrate??
on Feb 9, 2017 at 8:26:17 am

Hi all,

Like many, I am trying to burn some DVDs without the compression making my videos look pixelated/blurry. I am exporting them using Premiere Pro. If I export as mpeg2 file with a high bitrate that matches the original source (bitrate was something like 12 or 15... or 18), the outputted movie generally looks quite good. If I drop the bitrate to something more like 8, the movie looks terrible - blurry and pixelated in some places. And it is my understanding that around 5-8 is standard bitrate for burning a DVD..?

Since many laptops no longer come with DVD burners I have just one option for how I'm going to burn these - I have to sneak into a local university computer lab and use the only software they have - Windows DVD Maker. So this is why I'm asking this here instead of just doing a test run. The situation is a bit complicated.

IF I take my mpeg2 files with bitrate of 12 or max 18 into the burning program, will it work? Will it just compress it to 8 anyway? Will it take it at all or spit it out? Would it still look a little better than the 8 bitrate export from Premiere, or would it look worse and I should use my 8 bit versions anyway? etc etc.

The other outside option is that Windows DVD Maker can also take .avi files but I've noticed when I export them from Premiere I seem to get one of two things - either a giant 100 gig file for avi uncompressed, or again a blurry pixelated file for the compressed .avi. So in the end I figured it just best to export straight as an mpeg2...?

Thanks for any help you can give me - I don't know much about DVDs so I've never had to do this before.


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Alexander Kallas
Re: MPEG2 bitrate??
on Feb 9, 2017 at 11:15:37 am

Export as a self-contained movie from your editing time-line, and then compress to m2v. The bit-rate will depend on 1. the length of your movie, i.e. for a single layer DVD5 or double layer DVD9. 2. wether you want to duplicate or replicate (a matter of reflectability) and use of constant or variable bit-rate. Read up on this stuff and you will arrive at the solution for your project.

Cheers
Alexander


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Jeff Pulera
Re: MPEG2 bitrate??
on Feb 9, 2017 at 4:20:21 pm

Hi Ali,

Of course your exports at a higher bit rate look better - however, you have not yet burned them to DVD, at which point the data rate WILL be lowered to fit within the DVD specification and you would lose any quality advantage.

What version of Premiere do you edit with? Adobe Encore is the typical choice for DVD authoring. If you have Premiere CC, you can download Premiere CS6, and Encore CS6 will come with it.

https://helpx.adobe.com/encore/kb/encore-cs6-installed-cc.html

The workflow would be to export from Premiere as MPEG-2 DVD format, which is different than just straight MPEG-2. You'll need to use an appropriate bit rate that will allow your movie to fit the disc. A rule of thumb is 560/minutes= bit rate, but don't exceed 8 for shorter movies. I usually round down the result a bit for safety margin. One can also employ a bit rate calculator, but you have to be careful about entering the correct values into every box, or the formula does not come out right.

http://dvd-hq.info/bitrate_calculator.php

Exporting as MPEG-2 DVD results in two individual files - .m2v video and .wav audio. In Encore use Import as Timeline and bring in both assets together. Encore will NOT transcode the video, however the audio will be transcoded to Dolby Digital AC3 audio by default.

If you do NOT want to use Encore for some reason, and wish to go with Windows DVD Maker, that does not accept the separate audio and video files. What I do in that case is simply export from Premiere as an .avi file, using the NTSC DV preset. The DV codec is only mildy compressed so it looks great, and DVD Maker will accept that file and it will transcode to MPEG-2 for you behind the scenes.

If your source video is HD, when you set up the Export Settings from Premiere to export as SD (either MPEG-2 DVD or DV widescreen), you may see narrow black bars on the left and right side of the output preview. Change output scaling to Scale to Fill to eliminate those bars. Also check the box for Max Render Quality - this will improve the downscale quality of HD to SD.

Thanks

Jeff Pulera
Safe Harbor Computers


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Alexander Kallas
Re: MPEG2 bitrate??
on Feb 10, 2017 at 12:14:35 am

[Jeff Pulera] "The workflow would be to export from Premiere as MPEG-2 DVD format, which is different than just straight MPEG-2. "

OK please, just how do they differ?

Cheers
Alexander


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Ali Krauth
Re: MPEG2 bitrate??
on Feb 10, 2017 at 9:11:04 am

Yes I notice when using Mpeg2-DVD it uses the lower bitrate and the file looks worse than I am hoping (though it might just be an accurate reflection of what it will look like on the DVD at SD quality anyway) so I will try the .avi NTSC dv and see if that looks better once burnt ☺ thanks! If it still looks rough I will be begging the art gallery to use media players instead because this messing around with SD quality stuff is really no fun. ☹


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Alexander Kallas
Re: MPEG2 bitrate??
on Feb 10, 2017 at 9:32:56 am

Ali, mpeg2 is mpeg2. I think what Jeff has referred to, and what is confusing you, is that you are using limiting encoder presets. Specialised encoder software allows you more control e.g. Apple's compressor. My post was referring to this, the variables that you have to consider to get the best encode. This was confusing you, your presets gave you little/no control over the parameters.
Hope this helps you to understand what you are dealing with.

Cheers
Alexander


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Jeff Pulera
Re: MPEG2 bitrate??
on Feb 10, 2017 at 3:57:19 pm

DVD Video is an official specification. The MPEG-2 file burned to a DVD must meet those narrow specifications. That is why Adobe has a specific MPEG-2 DVD encoder setting, and we don't just use MPEG-2 in general. Go to Media Encoder and choose MPEG-2, and then look under the Video tab - you will find lots of advanced settings like Macroblock Quantization and Intra DC Precision for instance. Most people, myself included, have no idea exactly how everything needs to be set up to be DVD-compliant.

If the MPEG-2 file we supply to the DVD authoring software does not meet DVD specs - it WILL get transcoded to a format that does meet spec. Now look at MPEG-2 DVD preset and check video settings - much simpler - you can't tweak much, since it is set up behind the scenes already for us to be DVD-compliant.

So that's the difference. We can't just use any old MPEG-2 file and expect it to be accepted by the DVD authoring software. It will get converted in that software if the specs are not correct.

Thanks

Jeff Pulera
Safe Harbor Computers


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Alexander Kallas
Re: MPEG2 bitrate??
on Feb 10, 2017 at 10:41:20 pm

OK Jeff, these are combination delivery presets. Pure mpeg2 (what I am referring to here) is just the start for using visual files. From here in professional work, you can create your delivery settings, keeping in mind that audio is separate and is encoded separately, e.g. in ac3. There is not enough control for me in these combination delivery presets..
Hope that helps

Cheers
Alexander


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