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rana
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PostPosted: Tue Jan 07, 2003 8:27 pm 
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Joined: Sun Dec 16, 2001 7:27 pm
Posts: 6140
Hi Sunnyaudit,
Finally found your thread, “What Makes Good DVD Authoring??”

Mhafner’s dictat in that thread is right to the point.

To save further searching or link clicking, I am pasting mhafner’s post here:

http://www.zulm.net/cgi-bin....thoring

WHAT MAKES GOOD DVD AUTHORING??

Hi,
Good question. A DVD offers a video version of a film and in some cases supplements as well. I'm not going to talk about supplements except that I do not consider them an asset unless they do not reduce the image and sound quality of the film itself (and they usually do by taking bits away from the main feature).
For me an excellent/reference DVD is a DVD that
- looks like the film master used (as good as possible given
the limitations of the medium compared to 35mm film) and
not like digital video, especially artifact ridden video.
Naturally the better the film master is the better the
DVD can look as well. Excellent DVDs need an excellent
film master to fully use the potential of the format.
- looks good even on the most revealing watching conditions,
such as when projected on a 2-3m screen with a state of
the art CRT or DLP projector. And not only when watched on
low resolution standard TV monitors sitting 7 or more
screen heights away and with suboptimal lighting
conditions (bright room instead of dark room).

Excellent DVDs are rare among Western DVDs and not
(yet) existent among Indian DVDs.
The reason is it costs more than a run of the mill DVD and
you need to know exactly what you are doing during the
mastering stage. Unfortunately many don't want to spend the
money or don't know/care how to get the film look and avoid
the video look.
To get a superior film-like DVD one must
- transfer from original film elements, using digital
component video (HD -> PAL/NTSC or direct to PAL/NTSC)
- use a state of the art telecine that produces sharp
pictures (almost) free of digital artifacts
- use the correct theatrical aspect ratio and 16:9
enhancement for widescreen films.
- master the NTSC DVD with a corrct 2:3 pulldown so correct
progressive film frames can be reconstructed by
progressive DVD players and external video processors that
have inverse 2:3 pulldown implemented. Do not do format
conversion from PAL to NTSC, NTSC to PAL, HD to PAL/NTSC
which compromises the original film frames and introduces
motion artifacts during playback. If you do the film look
is lost and it looks like video, even if everything else
is done optimally.
- color and contrast correct the film digitally for optimal
playback with 8bit video, preferably in the telecine or
on the 10 bit HD master so rounding errors and
recompression artifacts are minimised.
- use a state of the art MPEG encoder and use a high enough
bit rate to handle the enormous detail present in a sharp
transfer. Optimise the compression by carefully tuning the
MPEG-2 parameters to the image content.
- not optimise for small TV screens where some edge enhance-
ment usually looks 'nice', but looks ugly on bigger
screens. People that like the pseudo sharp look can use
their TV sharpness function. Forcing everbody to endure
enhanced edges makes no sense. It also destroys the film
look. Don't use edge enhancement at all. Make a naturally
sharp transfer and use a high bit rate if sharpness is
what you want (and hopefully you do! .
- not reduce sharpness in horizontal or vertical direction
with a low pass filter so a lower bit rate can be used
and there is less flicker on interlaced monitors.
- not apply noise reduction to the transfer since it
inevitably leaves a trail of artifacts behind that again
destroys the film look. If the film master is too noisy
use a better master. If none is available encode at the
highest bit rate. Use high quality digital restoration
methods if film defects are too annoying otherwise, but
not a real time general purpose noise reducer. Be aware
that edge enhancement and noise reduction is often per
default built into and active in telecines and MPEG
encoders alike and may actually be active while you are
not aware of it. In some brands/models you can't turn it
off, EVEN IF YOU WANT TO! In that case ask for software/
hardware updates and insist on the possibility to turn
it off. This situation is wide spread and affects top
films like "Star Wars: The Phantom Menace" which has some
excessive edge enhancement. But Fox plays dumb and denies
they applied any. A simple look at the picture proves them
wrong. Scary.
- Concerning sound quality use again the best sound masters
available. Use the high bit rate Dolby Digital or DTS.
Don't generate pseudo 5 channel mixes from mono sources
and don't reduce the dynamics of the master. Instead map
the loudest sound of the audio master to 0DB so the full
digital resolution is used and no bits wasted.

If you do all of this you will get a DVD that looks and
sounds remarkably like the film master, film-like, natural,
including the masters artifacts (speckles, scratches, grain,
out of focus shots etc.). If you want to get rid of the
film masters artifacts use a better master or CAREFULLY
apply digital methods that do not add any new (visible)
artifacts.
Such a DVD looks better than bad HD-TV. Actually most non
experts will think it is HD-TV when watching it with high-
end equipment. It looks great! Only good HD will clearly
show the still existing limitations of such a DVD (except
for good 35mm prints, of course).

cheers
Michel Hafner
http://www.imdb.com
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sknath
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PostPosted: Tue Jan 07, 2003 8:34 pm 
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Joined: Mon Dec 03, 2001 4:17 pm
Posts: 2853
Location: Canada
Wow... Sunny there you go... Hafner has stated it quite lucidly.. I just mentioned the starting point but he has gone abt describing the various algorithms u would need to make the print a state-of-the art print.

He says u should need a high-bit-rate for getting the visual clarity in the film... You get a visual clarity in the following ways... Less blockiness and also.. during fast motion sequences if you allocate more bits towards the motion vectors you can significantly improve the spatial resolution of the film. Also I will concur with him when he asks you to desist from using any edge enhancement techniques..as you can check that out urself...take any image in PaintShopPro and enhance the edges.. you get a highly disconcerting image !

But these are subtelities you would use when you actually generate the Master... The actual cost of making a DVD is here... replication is a fairly starightforward process, !

Please direct this information to Ayngaran and share with us what they have to say !
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sknath
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PostPosted: Wed Jan 08, 2003 12:38 am 
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Joined: Mon Dec 03, 2001 4:17 pm
Posts: 2853
Location: Canada
Sunny make sure you check out this thread too ...
http://www.zulm.net/cgi-bin....;t=3254
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DragunR2
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PostPosted: Wed Jan 08, 2003 1:54 am 
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Joined: Wed Dec 05, 2001 3:16 am
Posts: 4259
Yes, please tell Ayngaran to use NO EDGE ENHANCEMENT WHATSOEVER. They've used very little so far, but none would be even better.
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ali
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PostPosted: Wed Jan 08, 2003 12:09 pm 
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Joined: Wed Nov 14, 2001 2:06 pm
Posts: 4944
Location: UK
bhaskar wrote:
... wouldn't it be better to ask professional companies who do progressive transfers eg UK DVD companies?

Now you're just being silly :laugh: Should be locked up for coming up with a ridiculous idea like that :p

Ali :eek:
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congress
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PostPosted: Wed Jan 08, 2003 12:54 pm 
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Joined: Tue Dec 04, 2001 11:29 am
Posts: 1028
Location: Singapore
DragunR2 wrote:
Yes, please tell Ayngaran to use NO EDGE ENHANCEMENT WHATSOEVER. They've used very little so far, but none would be even better.

Unless of course if a inter positive is produced from the negatives...most Indian prints are bad in shape so a little edge enhancement is necessary...ultimately the source is the most important part.
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ganti
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PostPosted: Wed Jan 08, 2003 2:25 pm 
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Joined: Mon Feb 04, 2002 3:45 pm
Posts: 515
Location: columbus
Dragun
Quote:
Yes, please tell Ayngaran to use NO EDGE ENHANCEMENT WHATSOEVER. They've used very little so far, but none would be even better


I have songs from over 40 movies (7 DVD's) from their songs collection. These disks have more EE than DEI (DEI was also used lot of EE). Overall when you watch it in revealing conditions,Newer EVP Telugh disks have pleasing PQ than Ayngaran.



Edited By ganti on 1042035981
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Zoran009
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PostPosted: Wed Jan 08, 2003 5:18 pm 
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Joined: Mon Dec 03, 2001 5:53 pm
Posts: 14989
People who like EE they have to have it!!who knows, it is a curse they cant stand it!!

I prefer, more smooth, film like picture, easy on eyes!! my taste!

One of worst edge enhanced dvd I saw was CT Crouching tiger!!

BTW!! DTPH orig version was also cursed with GROSS EE!!



Edited By arsh on 1042046635
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ganti
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PostPosted: Wed Jan 08, 2003 5:34 pm 
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Posts: 515
Location: columbus
Arsh bhai,
CT is notorious for their dreaded EE. I hate them.
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ganti
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PostPosted: Wed Jan 08, 2003 6:47 pm 
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Joined: Mon Feb 04, 2002 3:45 pm
Posts: 515
Location: columbus
A textbook reference on EE from Bjoern Roy.

http://www.videophile.info/Guide_EE/Page_01.htm
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DragunR2
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PostPosted: Wed Jan 08, 2003 9:37 pm 
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Joined: Wed Dec 05, 2001 3:16 am
Posts: 4259
Edge enhancement does not increase detail, Congress. It just causes ghosting around certain objects and is very annoying.

I have come across few discs that have no EE, and no Indian discs containing no EE. Ganti, I'll have to look at a few Ayngaran discs again to assess the EE levels. I'm sure your display is better calibrated than mine. I merely calibrated mine using the THX Optimode included on a DVD, hehe, except I turned sharpness to zero.
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mhafner
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PostPosted: Fri Jan 10, 2003 3:43 pm 
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Joined: Mon Dec 03, 2001 8:14 pm
Posts: 1086
Joining late...
Some quick remarks.
I have watched two Ayngaran disks so far in whole and had
a quick look at 1-2 others.
The main problems were
- Way too much aliasing in the pictures. It was so bad that
I thought there was no correct pulldown present. But that
was an error. The 2:3 pulldown is correct and the picture
progressive if you have inverse pulldown in your chain
that does not need flags. Obviously it would be better to
store 24 frames/s and set the flags properly so the saved
bits can be used for compression quality.
- The aliasing is most likely a telecine issue and/or some
processing step in between causes it. Ayngaran must stop
using outdated telecines in Indian DVD shops and use a
Spirit instead who outputs directly NTSC with the correct
pulldown and superior image quality.
- There were also DNR artifacts and some EE. Both must be
turned off and not applied.
- Bit level was too low at times and quite some blocking
was visible -> use higher rates and better encoder.
Use 2 discs for long films (before intermission and after
on seprate discs).
- use original negative or first IP, ask DP/director to come
and color correct during transfer. Avoid release prints.

cheers
MH
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Shahran Sunny Audit
 Post subject:
PostPosted: Fri Jan 10, 2003 5:22 pm 
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Joined: Tue Dec 04, 2001 12:28 am
Posts: 1373
Location: London, UK
mhafner wrote:
Joining late...
Some quick remarks.
I have watched two Ayngaran disks so far in whole and had
a quick look at 1-2 others.
The main problems were
- Way too much aliasing in the pictures. It was so bad that
I thought there was no correct pulldown present. But that
was an error. The 2:3 pulldown is correct and the picture
progressive if you have inverse pulldown in your chain
that does not need flags. Obviously it would be better to
store 24 frames/s and set the flags properly so the saved
bits can be used for compression quality.
- The aliasing is most likely a telecine issue and/or some
processing step in between causes it. Ayngaran must stop
using outdated telecines in Indian DVD shops and use a
Spirit instead who outputs directly NTSC with the correct
pulldown and superior image quality.
- There were also DNR artifacts and some EE. Both must be
turned off and not applied.
- Bit level was too low at times and quite some blocking
was visible -> use higher rates and better encoder.
Use 2 discs for long films (before intermission and after
on seprate discs).
- use original negative or first IP, ask DP/director to come
and color correct during transfer. Avoid release prints.

cheers
MH

I don't know which titles you saw but since Ezumalai DVD Ayngaran have been using Sprit Data telecine machine and instead of using digibeta they scan the film from the telecine and encode staright away to DVD. Source used are original negatives.

What I would like to know is how they can turn the scanned pictures into progressive? They have technicians working on this but I would also like to know from this forum and hopefully I could advise them an alternative route that might be better?
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rana
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PostPosted: Fri Jan 10, 2003 7:02 pm 
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Joined: Sun Dec 16, 2001 7:27 pm
Posts: 6140
Shahran Sunny Audit wrote:
since Ezumalai DVD Ayngaran have been using Sprit Data telecine machine and instead of using digibeta they scan the film from the telecine and encode staright away to DVD. Source used are original negatives.

What I would like to know is how they can turn the scanned pictures into progressive? They have technicians working on this but I would also like to know from this forum and hopefully I could advise them an alternative route that might be better?

Sunnyaudit, Progressive, Pseudo-progressive or interlaced, all are terms for convenience. The data on NTSC or PAL DVDs is always interlaced. If the interlaced data can be turned back into original film frames using indicators on DVD, we have been calling it Progressive. If the indicators are not on the DVD, but pixel to pixel comparison can detect the two fields making up one film frame, we have been calling it Pseudo-progressive. If the fields have been averaged to make up for the discrepency between film rate and TV field rate, then original film frames can not be re-created and we call them interlaced.

The process you described, indicates Ayyangran DVDs to be Progressive or at least Pseudo-progressive. If the repeated fields (every 5th) are actually un-neccessarily recorded, then it is Pseudo-progressive. If the fields that are required to be repeated are not recorded but are instructed to repeat the previous field, then it is Progressive DVD. By not recording the un-neccessary field (every 5th), you save 25% bit space as well.

Rana

P.S.

Sunny, you may want to check this link, that Ali provided in BTTF Screenshots thread, as well.
http://www.cs.tut.fi/~leopold/Ld/FilmToVideo/



Edited By rana on 1042225597
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mhafner
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PostPosted: Sat Jan 11, 2003 6:59 pm 
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Joined: Mon Dec 03, 2001 8:14 pm
Posts: 1086
Shahran Sunny Audit wrote:
I don't know which titles you saw but since Ezumalai DVD Ayngaran have been using Sprit Data telecine machine and instead of using digibeta they scan the film from the telecine and encode staright away to DVD. Source used are original negatives.

What I would like to know is how they can turn the scanned pictures into progressive? They have technicians working on this but I would also like to know from this forum and hopefully I could advise them an alternative route that might be better?

Spirit used? But then the are not transferring in India.
There is no Spirit in India as far as I know, only a
"Shadow" (at Shemaroo). Where are they doing the transfer
on a Spirit?
I have seen Kannathil Muthamittal and Alai Payuthey which
both have not a Spirit quality picture. Maybe the damage
was done later on.
The Spirit has an option to dump progressive frames on
hard disk, I think. But this is a waste of time unless you
are willing to take theses disks (which must store in the
terrabyte region for uncompressed data) and feed the data
directly into your Software MPEG encoder. I don't think
anybody is doing this, but the quality would be top.
Usually the Spirit outputs 480i NTSC or 576i PAL or 1080i
HD to a tape with some compression and color subsampling.
The DVD is then made from the tape via a more or less long
processing chain where quality can go down the toilet for
many reasons.
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