DVD Shrink - towards its limits?

[Ghitulescu]

Most people around here consider a backup using various GUIs and CCE as superior to DVD Shrink.

I had a chance to compare two DVDRs from the same DVD9, one using CCE (x passes) and the other using DS 3.2 at ca. 90% (the rest being extras, languages, logos etc.).

I couldn't discerne one from the other.

Question: When does it really begin a difference between the two aproaches?

[manolito]

You are walking on thin ice here...;)

This has been discussed many times before, and if you ask 10 people for their opinion you will probably get 10 different answers.

Ask JDobbs (author of DVD-Rebuilder and BD-Rebuilder), and he will tell you that a complete reencoding using a high quality encoder like CCE or HC will always give you a better quality than a CDT (Compressed Domain Transcoder).

Others will tell you that at least for a smaller compression ratio (like up to 10%) it is even desirable to reuse the original motion vectors.

And there are a lot of other factors which have an influence on the output quality:

DVDShrink settings:
Performing a deep analysis plus usig AEC (Adaptive Error Correction) will have an impact. Selecting Sharp, Maximum Sharpness or Smooth can make a big difference in quality depending on the source characteristics.

The source characteristics itself:
A less complicated source without high detail and high motion is usually easier on a transcoder like DVDShrink.

Your viewing device:
If you watch your movies on a big screen LCD you will notice blockiness much more compared to a CRT TV. CRTs are very forgiving in this respect.

My personal experience:
I still refuse to trash my 28" 4:3 CRT TV. Several test conversions showed no visible difference between a transcoder and a real encoder up to about 70% compression. I even prefer DVD2One over DVDShrink now for its speed, and I could never detect any difference in quality between DVD2One and DVDShrink in its fastest mode (which is still a lot slower than DVD2One).


Cheers
manolito

[laserfan]

Several test conversions showed no visible difference between a transcoder and a real encoder up to about 70% compression.
My experience is similar, though I picked about 75% as the cut-off point.

But frankly now that DVD+R DL discs have dropped close to $1 buck each, I tend not to do any shrinking at all anymore (I just like to "Jump to Movie" and fiddle with subtitles).

[Chetwood]

Actually, now that HDDs are that cheap there's no need for transcoding anymore, everything goes straight to my media center. I'm still using Shrink for ripping movie only and stuff but that's about it. That little quality difference (presumably) achieved by Rebuilder was never worth the extra encodig time for me.

[Ghitulescu]

Thank you all of you for your answers.
This has been discussed many times before, and if you ask 10 people for their opinion you will probably get 10 different answers.

My mistake, I searched a bit, nothing relevant found. Maybe I should have searched a bit more ....
Ask JDobbs (author of DVD-Rebuilder and BD-Rebuilder), and he will tell you that a complete reencoding using a high quality encoder like CCE or HC will always give you a better quality than a CDT (Compressed Domain Transcoder).
He's probably right, but I'm relatively positive in saying that DS 3.2 is faster than CCE x! passes at negligible quality loss.
Others will tell you that at least for a smaller compression ratio (like up to 10%) it is even desirable to reuse the original motion vectors.
That was also my impression. However, I think that the answer should have also taken into account the bitrate. I used DS more for DVB than for DVDs, and some DVB senders are really "cheap", so even 5% would have a visible impact on the viewing quality.
Your viewing device:
If you watch your movies on a big screen LCD you will notice blockiness much more compared to a CRT TV. CRTs are very forgiving in this respect.
I'm not sure if it's an intrinsec characteristics of an LCD (technological limit) or a bad setting, but all the LCDs I've seen feature an unnatural sharpness ... [/QUOTE]

But frankly now that DVD+R DL discs have dropped close to $1 buck each, I tend not to do any shrinking at all anymore (I just like to "Jump to Movie" and fiddle with subtitles).
The problem was not the price but the burning issues of DL disks. There are disks that are bigger than DVDR even with all other languages removed ...
Actually, now that HDDs are that cheap there's no need for transcoding anymore, everything goes straight to my media center. I'm still using Shrink for ripping movie only and stuff but that's about it. That little quality difference (presumably) achieved by Rebuilder was never worth the extra encodig time for me.
That was also my impression, judging only at 90% (some 5GB -> DVDR).
Concerning the mediaplayer, I was already in quest for one -> http://forum.doom9.org/showthread.php?t=150994

[setarip_old]

@Ghitulescu

Hi!I had a chance to compare two DVDRs from the same DVD9Did you play/view them concurrently, side by side, on two identical monitors?

[henryho_hk]

I wish DVDShrink let me compress LPCM track as AC3 or MP2.

[Ghitulescu]

@Ghitulescu

Hi!Did you play/view them concurrently, side by side, on two identical monitors?

I couldn't, as I have only one DVD player. Putting the other one into the BD player would have spoiled the results, as the BD player is much better in upscaling. Although it has "Source direct" it features also no usable analog output and the DVD player has no HDMI.

I simply watched some passages I think were representatives (dark, noise, film grain, rapid mouvements, camera pannings etc.) watching mainly for blockiness and other artefacts. I also did a comparison towards the original to see any signs of degradation.

Setup: Pioneer DV-464 using RGB (no image enhancement), Pioneer 5090 (ICF, also no image enhancement as the source was PAL), viewing distance ca. 2.5-3m (30cm for some critical passages), my good eyes, my experience that told me where to look. If I'm using the Pio BD, the differences would be unnoticeable (for 5GB->DVDR, ca. 90%) compared to the original. The same occured also when I played all three on my [again] Pio DVR7000 hooked on a 55cm Sony trinitron.

[Wombler]

Pick a more difficult disc and you'll see a massive difference.

Try 'Saving Private Ryan' and watch the scene where they land on Omaha beach.

Some discs won't compress satisfactorily with any software.

Rammstein's 'Volkerball' is a good example.


Wombler