Delivery formats for HD DVDs

[DarrenD]

Mark (Hulk)

I got lost on this square/non-square argument ages ago (see my previous threads here and on DMNforums).

I tried all 8 combinations of square/non-square, lower/upper field and M-path/non-MP (when adding square pixel .BMP/.JPG images). I had video layer V1=4:3 DV .AVI footage and V3=.BMP image of a circle with "12 o'clock" thick line. I put a M-path so the image rotated 360 degrees. I put all 8 combinations of MPEG-2 outputs onto a DVD+RW.

I viewed it on my TV to find the correct settings. The wrong ones caused the footage to be squashed slightly (play footage from camcorder to TV - a post-it note on the TV on a static object helped). Others had the circle become an ellipse when rotated. I also noticed my TV was not correctly adjusted (square object camcordered direct to TV and used a ruler).

This approach allowed me to see the reality of what the theory said. The above shows the process so you can repeat it. Cant' remember the exact solution though (:

[DarrenD]

General

Boy I hate this 1000 character limit. The last post had to be cut down so much!

[DarrenD]

Whoops, forgot the final summary...

I use a 4:3 camcorder and want to burn DVDs for TV use.

My tests showed that I needed non-square pixels/lower field first/can't remember the moving path settings [I am at work]. The standard MSP template DV (PAL) has 4:3 settings but uses square pixels for some reason. So simply use the standard one and tick use non-square pixels.

See my threads http://forums.murc.ws/showthread.php?s=&threadid=47737 and http://www.dmnforums.com/cgi-bin/rea...oppostid=24235 for more details/history.

I used the term M-path before, to get less than 1000 chars.

[Hulk]

Darren,

Clever method of confirming the non-square pixel theory.

I've come to understand that when you are working with resolutions that are 3:2 when using square pixels, i.e. multiples of 720x480, and the video is to be viewed on a TV, then use non-square pixels so 4:3 aspect ratio can be attained.

If you want the video to be viewed on computer monitors or other square pixel viewing devices then convert the video to 640x480 or some multiple of that, which is 4:3 when using square pixels, and use square pixel rendering.

So it all depends on your output resolution. 640x480 is square and 720x480 is non-square, including all multiples of each.

That's how I've reconciled theory and practice. Of course all these examples are NTSC but PAL is basically the same with different numbers.

- Mark

[wkulecz]

Don't know if its relavent or not, but my experience watching HDTV via Time-Warner cable is that live action sports (NFL Football) on CBS broadcast in 1080i are very good.

While 720p as broadcast by Fox and ABC are so full of freeze-frame and other arifacts that I watch the cagme on the old analog broadcast channel!

Sitcoms generally don't show any major quality differences between the 1080i on CBS and 720p on ABC.

HBO HDTV is uniformly good (image quality), as is Mark Cuban's HDNET stuff.

--wally.

[Hulk]

Wally,

It must be hard to watch SD broadcast after having HD available!

Mark

[wkulecz]

It must be hard to watch SD broadcast after having HD available!

Not really, given how badly the ABC & FOX broadcasts freeze-frame and artifact during pans & zooms. Often there is an audio "breathing" that modulates the crowd noise that is extremely irratating.

But it is no contest for "normal" shows where the HDTV encoding was apparently not done in real time.

What impressed me a lot more than I expeceted was the image quality improvement gained whan watching commercial DVDs in 480p. Same old player, I hooked it up initially the way it was for our old TV but to component inputs, pulled up the menu to enable progressive output and was blown away by the improvemnet after the player "rebooted".

--wally.

[Hulk]

I don't begrudge my cable TV company for charging me for the service, but when the starve the bandwidth so much that macroblocking is apparent, or worse as you mentioned, freezing, then I get upset.

I wonder if it's the real time encoding or just that some channels aren't allocated the required bandwidth.

- Mark