Upconverting from NTSC vs PAL? - AVS Forum | Home Theater Discussions And Reviews
Baselworld is only a few weeks away. Getting the latest news is easy, Click Here for info on how to join the Watchuseek.com newsletter list. Follow our team for updates featuring event coverage, new product unveilings, watch industry news & more!


Forum Jump: 
 
Thread Tools
post #1 of 6 Old 04-08-2014, 01:40 PM - Thread Starter
Member
 
lasitter's Avatar
 
Join Date: Nov 2010
Location: Pawtucket, RI
Posts: 47
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Upconverting is a standard feature for players nowadays, but I'm having trouble conceptualizing the impact on quality on converting from a PAL disc vs to NTSC.

Here's the scenario:

Tivo records something in Hi-Def, and then to make a DVD out of it I have to convert it into MP4 or some other format first. Part of this process involves selecting PAL or NTSC as an output format before burning the file, and 576i just seems like it would have to be higher resolution than 480i (NTSC).

It seems to me that in the process of converting down from 720p (Tivo?) you throw away information that can't ever be regained in the upconversion process again.

Of course the perfect solution would be burning a Blu-ray disc, but that's lots more money.

Is this explained for me anywhere? Thanks.
lasitter is offline  
Sponsored Links
Advertisement
 
post #2 of 6 Old 04-08-2014, 06:15 PM
One-Man Content Creator
 
wmcclain's Avatar
 
Join Date: May 2006
Posts: 18,580
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1123 Post(s)
Liked: 534
DVD Video has a maximum resolution of 720x480 @ 60hz or 720x576 @ 50hz. Those are standard definition resolutions. You're right: once you throw away higher resolution you can't recover it.

I don't have a tivo; are you sure you have to convert to DVD Video. Media files like mp4 are not constrained by the older limits these days.

-Bill

Review older films here: 1979 and earlier | 1980s | 1990s | Combined reviews: Strange Picture Scroll
Unofficial OPPO FAQS: BDP-103 | BDP-93 | BDP-83 | BDP-80    
wmcclain is online now  
post #3 of 6 Old 04-08-2014, 07:08 PM - Thread Starter
Member
 
lasitter's Avatar
 
Join Date: Nov 2010
Location: Pawtucket, RI
Posts: 47
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by wmcclain View Post

I don't have a tivo; are you sure you have to convert to DVD Video. Media files like mp4 and not constrained by the older limits these days.
This is the obvious answer. I guess I don't! I suppose I could just burn the MP4 file to the media and go with that.

Thanks! I'll give that a try.

BTW: I did both NTSC and PAL and it seemed to me that playback on the latter was better.
lasitter is offline  
post #4 of 6 Old 06-04-2014, 06:28 PM
Member
 
Krispy Kritter's Avatar
 
Join Date: Jun 2006
Location: St Louis, MO
Posts: 70
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked: 11
I wouldn't waste the time or money burning to DVD. Output from the Tivo into a mp4 file to maintain the quality, and then find a player that can play the mp4 files. There are numerous options for playback, newer mid to high end TV's have file playback support, as do DVD players, and Blu-Ray players. There are also dedicated players such as the WD Live (and many others) or gaming systems (ie: XBox, PS3, etc.). And of course you could use a PC/HTPC.
Krispy Kritter is offline  
post #5 of 6 Old 06-04-2014, 07:24 PM - Thread Starter
Member
 
lasitter's Avatar
 
Join Date: Nov 2010
Location: Pawtucket, RI
Posts: 47
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I completed an experiment taking the MP4 files from the Tivo and converting them to .m2ts, and buring an UDF 2.50 DVD.

Popped it into the Blu-ray, and it worked like a charm. Treated it just like it was a Blu-ray disc. Resolution was fantastic, too.

Of course it would spook most users that would see the disc and assume it was meant for a DVD player.
lasitter is offline  
post #6 of 6 Old 03-08-2015, 12:49 AM
AVS Special Member
 
Mr.D's Avatar
 
Join Date: Dec 2001
Location: UK
Posts: 3,319
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Liked: 17
I admit that I'm unfamilar with Tivo but most cnsumer black boxes deal with NTSC to PAL transcodig in a couple of ways.

1. Its just NTSC 525/60 unmolested but with a PAL formatted colour frequency signal. Gives you slightly better color ( assuming a component source) but risks chroma/luma crosstalk if you combine it into composite. ( you ain't doing that).

2. The box either does frame culls or frame repeats to create field structure thats legal 525/60 or 625/50 (NTSC/PAL for want of a better word). This stutters and looks awful.

3. The box is smart enough to recognise the progressive nature of the original material if its 24p and inverse telecine this to 23.976 fps out of 60i . This then gets sped up by 4% to be 25fps for PAL which is then einterlaced to 50i. this is the cleanest way but is material specific ; native 30 or 60 fps material cannot be handles this way).

4. The box completely reinterpolates every single frame using vector analysis and regenerates the frames . This looks soft and often has artifacts where the interpolation breaks down: think frame interpolation on TVs.

What one does yours do ? No idea

digital film janitor
Mr.D is offline  
Sponsored Links
Advertisement
 
Reply HDTV Software Media Discussion



Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off