New hd and explianation (1 Viewer)

[John Alvarez]

A friend just bouht this set.
http://www.mitsubishi-tv.com/televis...ils.asp?id=192
I tied to explain that his dvd player isn't going to play at 1080i. Help me explain in an easy way....:frowning:

 

[John S]

It will be displayed at a scaled to 1080p.....

Easy way to explain it is that all digital displays must scale all images to the native panel resolution. Just a fact of life.

DVD starts out at 480i, that is really all you get no matter what you do to it.

 

[ChrisWiggles]

This is misleading. The best way to view an image is to upscale the image to a higher resolution. A 480i source displayed at a higher resolution like 1080p is far superior to a 480i source displayed at 480i.

 

[Michael TLV]

Greetings

Will assume that the scaling does not degrade the signal though. If that occurs ... then native is better than scaling.

Regards

 

[ChrisWiggles]

true, assuming good quality scaling .

 

[Allan Jayne]

The screen, or rather the image projected on the screen, is at all times divided into pixels 1920 across by 1080 down for this model of TV set.

The DVD player outputs a frame of pixels 720 across by 480 down.

You can think of the scaling process this way:

Since each incoming video frame has 480 rows of pixels while the screen has 1080 rows, the incoming rows are duplicated so that all 1080 rows on the screen are filled in.

Since each incoming row has 720 pixels while the screen has 1920 pixels across, the individual pixels are repeated and spread out so the entire screen width is covered.

(The actual process more likely uses blending rather than outright repetition of pixels.)

If the TV did not duplicate (or blend) pixels or rows of pixels, the entire picture would occupy the upper left corner of the screen (first 480 rows and first 720 pixels in each occupied row) leaving the rest of the screen blank.

Whereas a 1080i HDTV broadcast has 1080 unique rows of pixels per frame so it is not absolutely necessary to duplicate rows. The amount of original picture detail is more than twice that vertically and more than twice that horizontally compared to what is provided by a DVD.

(Note: The rows of pixels for 1080i arrive in groups of 540 in the order 1, 3, 5, 7, ..., 1075, 1077, 1079, 2, 4, 6, ..., 1078, 1080. Non-progressive scan DVD players also output odd and even groups, of 240 rows each. For some subject material the picture is actually better if some repetition and blending is done within each group as opposed to leaving the entirety of the odd group on the screen when the even group, likely with some subject motion in progress, is filled in and vice versa.)

Video hints:
http://members.aol.com/ajaynejr/viddoubl.htm

 

[John Alvarez]

He just bought the Denon 2910 to use with this set. Is that a good match up?

 

[Jay_Via]

werent there a handful of DVD players recently that "up-converted" to a 1080i signal over DVI? (or something like that). Friend of mine has one of the 1st gen Samsung DLPs and a DVD player that he said up-converts to 1080i

I dunno, i never really understood it all myself.

 

[Allan Jayne]

Using an ordinary DVD player and your friend's new Mitsubishi TV, the TV will convert the 480i from the player into 480p and then into 1080i*.

Using a progressive DVD player (in progressive mode) the player actually always initially brings the video off of the disk as 480i. The player will convert the 480i to 480p. The TV will convert the 480p to 1080i.

Using a DVD player that upconverts to 1080i the player will do both the conversion from 480i to 480p and the conversion from 480p to 1080i. The TV will display what it gets as-is.

* Given a DVD or non-hi-def source, if there is no blending of scan line content between adjacent 1080i fields, the content is better described as 540p than 1080i. Diagonal lines and edges can be made smoother with certain kinds of blending.

Since your friend already has the 1080i HDTV, an upconverting DVD player is beneficial only if it does the conversions better than the TV does them.

 

[John Alvarez]

Okay Sound Advice has screwed around and he is looking at this set now. How do they compare?

http://www.jvc.com/product.jsp?model...hId=125&page=1
Thanks for the help.

 

[John S]

Double drool... The 70" 1080p....


He should get it right away, and you help him with it, and return a full report right back here.