DVD too large with Autofit

[jeffnoone]

Using 2.5.3300
XP SP2 machine, with no burner installed

Added two 50 min files, and set up a simple 2-button menu
One file is 1280x720 mkv, 1.43GB
The other is 546MB mpeg4 avi 624x352

Anyway pressed Autofit, and made sure DL unticked - the program specifies 4.37 as the size itis targetting

I outputted as VIDEO_TS folder

However the total size of folder (right click in Windows)
4.45GB (4,787,779,584 bytes)

I then moved to another PC, and made a .iso with ImgTool - TOO LARGE by about 80MB
Similarly if I open folder structure in DVD Shrink, it say I need to shrink by 2.5% more

So the output is too big!!

Can I get SVCD2MPG to target 4.29, rather than 4.37GB?

Or what in the heck is going on here in what seems to be a fairly simple structure

Jeff

[Jikchung]

It's a source related issue, some aren't targeted accurately for conversion. That's what this option is for:

[jeffnoone]

OK, although that is disappointing as you are now transcoding twice

In my situation, is it better to let SVCD2DVD make a 8GB DL DVD, and then use DVDShrink

or
is it better to make a 4.45GB DVD with SVCD2DVD , and then use DVDShrink

[jeffnoone]

I tried using 2.5.3600, the most recent and also tried using a matrix from this site, but still stuck at 4.45

This is the first time I have run into this - is it common that files are too big?

I am pretty disappointed to have to transcode/recode twice

Is there no way to set a preference in the program to target (say) 4.29GB, rather than 4.37

I am no programmer, but I assume at some point in the calculation process, things are divided by 4.37

Can I ask for this as a feature request?

Thanks for great program otherwise

Jeff

[Jikchung]

OK, although that is disappointing as you are now transcoding twice

No, you only transcode once - with Shrink. SVCD2DVD uses an encoder.

In my situation, is it better to let SVCD2DVD make a 8GB DL DVD, and then use DVDShrink

or
is it better to make a 4.45GB DVD with SVCD2DVD , and then use DVDShrink

It's a percentage deal with shrink, 2.5% reduction will get you better results than 50%

This is the first time I have run into this - is it common that files are too big?

No, not common, your own experience shows that. Just be aware that files from certain sources - you know what I mean - may not encode as properly as you would like.

[jeffnoone]

No, you only transcode once - with Shrink. SVCD2DVD uses an encoder.

I was actually aware of the difference but just used loose language - the problem is still the same - the video gets recoded twice; once from .mkv to mpg, then from .mpg to smaller mpg

Therre is an inevitable loss of quality at both steps

It's a percentage deal with shrink, 2.5% reduction will get you better results than 50%

But that wasnt really the question I raised

SVCD2DVD introduces inaccuracies as it codes (compared to original), as does DVDShrink

So how much inaccuracy is there in total if we let SVCD2DVD use a high bitrate (8GB file) followed by DVDShrink to 4.3GB

compared to

SVCD2DVD using a lower bitrate to 4.37GB, followed by DVDShrink to 4.3GB

Which combination produces the better result?

It's a percentage deal with shrink, 2.5% reduction will get you better results than 50%

If the videos DVDShrink is going to work on, are identical - clearly true - but as above, what about when one video is (approx) twice the size of the other to begin with?

[Jikchung]

But that wasnt really the question I raised

That's exactly the question you raised - 2.5% reduction is better than 50% reduction with a transcoder. As to innaccuracies, I would challenge you to show me the difference between the original and a 2.5% reduction fron Shrink.

If, as you say, you are aware of the difference between an encoder and a transcoder, then you already know it's better to let the encoder do the heavy lifting...

[jeffnoone]

After some experimentation, there is another way to deal with this problem, besides the double-encoding/transcoding methods mentioned above

Not sure how practical this method is, but I found a way to "coax" SVCD2DVD to use a lower bitrate (so the two files now fit on a DVD). This is by restarting the process (I removed the log files and S2D files), and adding a small (5-6 minute) avi, as a third VTS. Then I press autofit. Then I save the project, then remove the 6min .avi, and the associated VTS
SVCD2DVD doesn't seem to recalculate the autofit, so it uses a lower bitrate, the one it determined when the 6 minute avi was there

Certainly more clumsy and time-consuming than running DVDShrink, but I continue to feel that repeated encoding/transcoding leads to poorer final image quality in the end. In the case of my original files, these started life in high definition format, then were encoded by some kind soul to .mkv or .avi. So they are going to get one or two more encodings/transcodings, depending on how you approach this

If you note that SVCD2DVD consistently underestimates the size of output from certain .mkv or .avi files, then above is another approach

[k_vic]

Take a look at this thread - https://forum.videohelp.com/topic285423.html#1413094

Not sure if this tweak is still valid, but sounds like something that would possibly fix your issue.

[ChrissyBoy]

Take a look at this thread - https://forum.videohelp.com/topic285423.html#1413094

Not sure if this tweak is still valid, but sounds like something that would possibly fix your issue.

this "tweak" is still valid and is certainly a good approach to this issue. It is the odd mkv file which seems to be problematic when it comes to estimations.

[jeffnoone]

Thanks to JikChung, ChrissyBoy and k_vic for the discussion

Redoing the project with this DVDSIZESAFTYMARGIN option would seem to be the "purest" solution, alternately DVDShrink

Regards
Jeff