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Hyphthetical question MPEG2-DVD files...

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Jan Janowski
Hyphthetical question MPEG2-DVD files...
on Sep 4, 2017 at 12:22:07 am

OK Jeff.... Here's a hypothetical question for you....

Regarding MPEG2-DVD Files exported in PPRO and used in Encore....

If DVD Max filesize is 4.7GB

And you create a MPEG2-DVD FIle less than 4.6GB (approx), then Encore will not encode, which is better....

However, if you create an MPEG2-DVD file Greater than 4.7GB, say it's 10GB in size.... Pix quality of MPEG2-DVD is theoretically better, because of the higher bitrate, but Encore Render then kicks in to reduce it to ~4.6GB... Which I assume from posts here that Encore Render is providing less quality...... Right?

So...(Assuming only one timeline file) for Maximum quality.... Keep MPEG2-DVD files exported from PPRO/AME to a size less than ~4.6GB, or Encore render kicks in...... Degrading quality.......

Right?

Looking for 1939 Indian Motocycle


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Jan Janowski
Re: Hyphthetical question MPEG2-DVD files...
on Sep 4, 2017 at 12:05:06 pm

And here's question #2 for you, Jeff.... Question based on PPRO MPEG2-DVD Encode vs. Encore Encode...

Say you have a long session in PPRO.... Which would look better after burn to DVD in Encore:

Go for the highest quality MPEG2-DVD Export.... Disregarding Converted FileSize altogether, such that the Encoded MPEG2-DVD Filesize is say 12-14GB, or higher..... And letting Encore Re-encode it to fit on 4.7Gb DVD.......

OR......

Exporting same long file In PPRO... Using settings that limit the size of the file to 4.6GB, so Encore doesn't have to encode it...

Which, in your opinion, would look better when viewed off DVD?

Looking for 1939 Indian Motocycle


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Jeff Pulera
Re: Hyphthetical question MPEG2-DVD files...
on Sep 6, 2017 at 2:37:30 pm

Hi Jan,

You always want to keep transcoding (conversions or re-encoding) to a minimum. Ideally, you encode to the delivery format directly from the camera source files. Camera and delivery formats are all compressed, meaning a lot of information is discarded in favor of producing smaller files. So now you are taking an already-compressed file (from camera) and compressing it again (for delivery). You don't want to do that multiple times, since more quality is lost each time.

There would be no benefit to encoding at a high bitrate, only to have Encore transcode (recompress) again.

Figure out the ideal bitrate to fit your material on the DVD, and encode once with best possible settings. The max bitrate for the DVD spec is I believe 9.8mbps (video and audio combined). 8mbps is the max recommended video bitrate, and the audio is usually compressed as Dolby Digital .ac3 at 224kbps. Uncompressed audio is also supported, but can take up a huge amount of room, like 1GB for a 2-hour video, which would take away precious space needed to raise the video quality.

Most DVD producers will not push the max bitrate for the reason that DVDs we make are burned, while Hollywood DVD discs are pressed. Totally different media! Some DVD players may take issue with very high bitrates on burned media, so better not to push it too hard. Depends on media quality also to some degree.

If you video is under 60 minutes, you can simply encode at 7 or 8 and know it will fit the DVD without doing any calculations. At that high bitrate, I will just use CBR which is Constant Bit Rate - all of the video is encoded at the same high quality. When the video duration starts getting beyond an hour, then you need to figure out the bitrate to fit the disc. A rule of thumb is 560/minutes = bitrate, so for a 2-hour movie, 560/120 = 4.6 and maybe round down just a little to allow for other overhead on the DVD, so 4.5 is a safe figure. Assumes you are not using a bunch of motion menus which can use a lot of extra space.

When encoding videos longer than an hour, quality can benefit from using 2-Pass VBR or Variable Bit Rate encoding. This encodes in two passes - the first pass just looks at all the video content to see if each scene is complex or more basic. Does it contain a lot of detail and motion which would benefit from a higher bitrate, or is it a static scene like a title screen or camera is not moving, in which case it will look just great at a lower bitrate.

Based on that first pass which analyzes the video content, the second pass then does the actual encoding, applying the appropriate compression to each scene to maximize efficiency, applying more bitrate where needed and less where it's not needed. With VBR, you will set an AVERAGE bitrate (the 4.5 from above for example) and then MIN and MAX bitrates also, so it might look like 2.5 - 4.5 - 8 for instance. The bitrate will vary scene to scene, not to exceed 8 or go less than 2.5, and averaging out to 4.5 overall. Having set the AVG, you know the encoded material will fit the disc in the end.

For a more precise bitrate calculation, use a bitrate calculator such as http://dvd-hq.info/bitrate_calculator.php

The only catch with using this calculator or similar is that you must put all the right numbers in each box - if you mess up one number, it throws off the entire formula and the result is then wrong.

I hope this is helpful.

Jeff Pulera
Safe Harbor Computers


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Jan Janowski
Re: Hyphthetical question MPEG2-DVD files...
on Sep 6, 2017 at 8:32:32 pm

Gives me much information... as I had hoped to receive! :)!

Printed out, and reading and further examinations commence Now!

Thanks for the in-dept answer...

Looking for 1939 Indian Motocycle


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Jan Janowski
Re: Hyphthetical question MPEG2-DVD files...
on Sep 8, 2017 at 2:32:27 pm

I have found a way around one issue, and have stumbled onto another!

I've developed a 2 Pass VBR that works fine without a second render in Encore.... and it can Output to DVD Folder without an error...
However... If I select Output to DVD Image, that option is Grey'd out.... Why? (I normally export to Image (ISO) because it is less prone to error out.. than Output to DVD Disc usually does)...

I tried Output to DVD Disc, and that fails 3/4 way through with Hardware Error, on any of 2 different disk burners...

Only difference in this project is I replaced a MPEG2-DVD Render based on CBR with MPEG2-DVD Render with 2-Pass VBR.... With CBR timeline... I can Output to DVD Image (ISO). Change to 2 Pass VBR-- Output to DVD Image is Greyed out...

Therefore, Can you Output to a DVD from a successfully created DVD Folder?

Should Output to DVD IMAGE with a 2-Pass VBR MPEG2-DVD Render Timeline work?

Looking for 1939 Indian Motocycle


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Jeff Pulera
Re: Hyphthetical question MPEG2-DVD files...
on Sep 8, 2017 at 3:40:55 pm

My usual workflow is to create a DVD IMAGE (.iso) and then burn that to DVD using third-party software. Always works. No idea why that would be grayed out, except I will say that sometimes when you take an existing project (having menus and such already in place) and you try to swap out the video source, strange things can happen in the project.

Thanks

Jeff Pulera
Safe Harbor Computers


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Jan Janowski
Re: Hyphthetical question MPEG2-DVD files...
on Sep 8, 2017 at 6:23:20 pm

Well, I've certainly had better days....

Encore CS6. I can no longer Output to BR or DVD Image.... on either desktop or laptop....

Even called up projects that I had done so before... and had been successful...

On both DVD and BR when I select Build tab, DVD DISC, DVD FOLDER, and DPP IMAGE all have build highlighted.
Wen I select DVD IMAGE -- Build goes low tally (Not Highlighted)
Blue Ray IMAGE does same (Not Highlighted).

both of the computers are doing same.

Looking for 1939 Indian Motocycle


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Jeff Pulera
Re: Hyphthetical question MPEG2-DVD files...
on Sep 8, 2017 at 6:28:09 pm

Screen shot please

Thanks

Jeff Pulera
Safe Harbor Computers


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Jan Janowski
Re: Hyphthetical question MPEG2-DVD files...
on Sep 8, 2017 at 6:39:47 pm

2 hours later.... and BOTH WORK FINE...

There was a destination (Encountered that before)....

It wasn't that both were operational simultaneously (at the end, I was comparing one against the other)...

Then it works! and it just finished making ISO of the VBR patch we talked about earlier......

Is Adobe still having us phone home? Could it have been that... ???
Both are on network here...
Both systems are 'clean' of spyware, etc...


Yeah... I just checked the ISO File. 4.177GB..... Thanks for that info....

As for the build going low tally..... You got me... but it happened to both systems.... and both systems are now OK..

Haven't been drinking.... but now that you mention it.........

Looking for 1939 Indian Motocycle


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Jan Janowski
Re: Hyphthetical question MPEG2-DVD files...
on Sep 8, 2017 at 7:05:22 pm

Jeff:
Here is the steps that I was following today when the iso isssue came up....
In PPRO (Where I edited down the 6 hours of footage to 3x 27 min shows per each DVD (5 DVD's total).
The settings I ended up using for the 2 Pass VBR
Quality 5, Rates: 3.67 6.81 7.92 Maximum Render Quality
That file, when finished, was imported as a timeline in Encore after deleting existing timeline.
Added Chapter stops to the new timeline, then linked the Menu buttons to chapter stops...
and then diagnostic check, then test play it, then build ISO....

ISO didn't work. went back to last project that did... It, too wouldn't... Fired up Laptop, went into older test dvd there. Same... ??? Try BR session... Same... ?????

And then suddenly they both worked!!!

I posted it was OK after creating ISO Build, and it didn't encode video!

I think Encore just wanted me to know who is in charge!

Looking for 1939 Indian Motocycle


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