At what percent is there noticeable quality in dvd shrink?

[fsuorange]

hello

i was wondering at about what percents normally, is there a noticeable quality loss using dvd shrink? Also, how does dvd-shrink shrink the file size without producing a bad picture?

Thanks

[andkiich]

It depends. Everyone will give you a different answer. Our eyes are different, our TV/DVD players are different.

Best thing to do is to test out a couple of backups with RWs and see wha tworks best with your setup.

[macleod]

the previous poster is right.

For a personal experience, however, I have a 32" Toshiba (non flat screen). I have done shrinks (always use deep analysis) to 40% and they look just fine.

[MOVIEGEEK]

As andkiich said it depends on a several factors but I don't go below 65%.

"Also, how does dvd-shrink shrink the file size without producing a bad picture?"

It transcodes instead of encode.Encoding will give you better results when reducing >40% but takes alot longer.
http://forum.digital-digest.com/showthread.php?s=ceb3fa5a7c1c825f07857176da191d38&threadid=29542

[jtoolman2000]

I just backed up The Right Stuff and it was 193 Minutes. I did a full disk back up. Brought thte menus and estras down to max compression and the movie ended up at about 60% Looks perfect on my 32" TV

[JohnnyCNote]

This is one area where "individual results may vary" definitely applies....

[Thunder In Paradise]

I have a 27" Phillips, and usually I start to notice background distortions (like if leaves are blowing on a tree, they don't move smooth, they move in a staccato type fashion), around 45-50% or higher, even with deep analysing turned on. Unfortunately, this compression ratio is sometimes unavoidable in long movies like Dr. Zhivago and The Godfather Part 2. As for foreground stuff, there doesn't seem to be any quality loss, usually it's only background stuff, and most of the time, it has to be in motion to notice anything anyways.

[lordsmurf]

What was the source bitrate? A blind % means zero.

[zanos]

I think once you get below 70% you will start seeing noticeable block noise but it won't get really bad until you go below 60%.

[tompika]

What was the source bitrate?
A blind % means zero.

I'm quoting this just in case y'all wouldn't wanna listen to lordsmurf

[funseeker40]

I compressed up to 63 % and looks like shit on my 29"sony TV with pioneer 533

[energy80s]

The compression ratio isn't as important as the original bitrate (as stated above). If a movie is already quite heavily compressed, then it will take very little extra compression before looking terrible. I was able to compress Raiders of the Lost Ark down from over 7 gigs to 4.3 gigs with no noticable loss of picture due to it having a very high bitrate of over 9 MBPS in some scenes.

[whomacuddy]

Agreeing with a poster about 'The Right Stuff' compressed to about 60% looks excellent on both TV and Computer however the only real giveaway is the scene with the Aboriginies dancing around the fire where the flying sparks become extremely blocky for some reason . It's up to the eyes to judge a depends on the content , the Right Stuff being a good example as the scene where John Glenn is launched works perfectly well despite the complexity of the image and the flames . On the whole anything above 60% is for the most part indistguishable from the source .

[El Chupacabra]

Agree with LordSmurf's comment -- that's the technical question, and the right question to ask.

But, as YMMV, here's my (non-technical) experience generally:

I found that compressing more than about 70% produces noticeable intermittent blockiness: on backups of X-Files episode discs; four 45-minute episodes on 1 DVD-R, using reauthor mode (drop all extras & menus), yields compressing around 63-65%. This yields some blockiness, but it's acceptable to me for a TV show.

For full length movies, I will reauthor just the main title in order to get compression above 80% (if necessary). I'll only keep the menus & extras if I can get the whole movie at 100% (i.e. not compressed). I would not go to 60-65% for a movie, as I have (so far) been able to reauthor any 2-hour long movie to fit with less compression, or no compression at all preferably.

My setup is an old Sony DVD player (from 1999), non-progressive scan, S-Video connection, hooked to a 36" Sony WEGA (non- HDTV, not XBR).