[renlopez]

When Sharp says "Nothing is Lost" in their ad campaign, are they asserting that truly deinterlace each individual 540 line field to make a true 1080p frame?


Cnet says that some 1080p sets employ "Simple Bob" deinterlacing in which the deinterlacing simply doubles one field of 540 lines to make 1080 and then tosses the other 540 lines.


The statement "Nothing is Lost" implies that you get every single line of 1080i resolution.


I went to moretosee.com but they don't say anthing about deinterlacing, probably because it would fly over the head of most consumers.


Can anybody confirm that in sharp 1080p sets, there are no lines discarded?

 

[alaskaman1666]

I think you may be reading more into their TV Ads than what is being stated. Sharp touts their top of the line D62 series LCD TV product as 1080P. Plasmas (read Panasonic) up until

CES didn't have a 50 inch 1080P Plasma. As you state, thew average customer doesn't consider how a set does deinterlacing, and doesn't even understand 1080P as opposed to

1080i.

 

[DBLASS]

1080I takes every other line, every other frame. CRT TVs were directly driven so that only through the perisistance of the phosphor did you not see any issue. With LCDs, the video processor has frame memory so the video signal in is written to a full frame of 1080 lines of memory. The LCD is written with a full 1080 lines as if it were receiving 1080P not 1080I.


The net should be the same. Deinterlacing 1080I makes 1080P, so there are 1080 lines and that is what is on the screen.

 

[ftaok]



Quote:
Originally Posted by renlopez /forum/post/0


When Sharp says "Nothing is Lost" in their ad campaign, are they asserting that truly deinterlace each individual 540 line field to make a true 1080p frame?


Cnet says that some 1080p sets employ "Simple Bob" deinterlacing in which the deinterlacing simply doubles one field of 540 lines to make 1080 and then tosses the other 540 lines.


The statement "Nothing is Lost" implies that you get every single line of 1080i resolution.


I went to moretosee.com but they don't say anthing about deinterlacing, probably because it would fly over the head of most consumers.


Can anybody confirm that in sharp 1080p sets, there are no lines discarded?

I believe that the 62U series of 1080p displays pass the "deinterlace" test. However, I think it failed the 3:2 test.


This is based on Gary Merson's tests for Home Theater Magazine.


He has a blog at hdguru.com and his latest tests are posted.


ft

 

[ftaok]



Quote:
Originally Posted by DBLASS /forum/post/0


The net should be the same. Deinterlacing 1080I makes 1080P, so there are 1080 lines and that is what is on the screen.

The net would be the same if the display does "proper' deinterlacing.


Many older sets, whether they are 1080p or 768p sets, used a simpler method to deinterlace. They took every other frame of a 1080i signal and threw it away. Then with the frame that they kept (1920x540), they scaled it up and displayed it for 1/30th of a second.


That's called the "bob" method of deinterlacing and the reason why on some older sets, 720p signals looked much better than 1080i.


Newer TVs are using the proper method for deinterlacing these days.

 

[DBLASS]

I think we are saying the same thing. With any flat panel TV (plasma or LCD) the interlaced signal is written into memory. It is "how" it is taken out of memory that is key. If the display has less resolution (or more, for that matter), then the video processor has to scale up or down to get the video image to fit on the display. It seemed the original question asked about 1080I mapping 1:1 on a 1080P. This is the most straight forward mode since there is no reason to scale. It is all the other types of resolutions and video feeds that require scaling.


Your "bob" method cetainly requires less video RAM. But they still have to "invent" the video lines between 540 and 720, and do it well.


DB