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Legend
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I notice there are no transmissions of 1080p (progressive scan), only 1080i.

Is a TV that does 1080p doing the scan sequence on its own frame buffer, meaning there is no difference in the transmitted information content, only the ways the TV presents it?

My understanding (or not) is there can be some motion shift (feathering, combing, line twitter, flicker) in the two interlaced scans and the progressive scan avoids this by presenting a frame as a film projector does. This would seem to need some interpolation smarts in the receiver and a faster scan rate to turn an "i" into a "p" scan sequence.
 

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RCinFLA said:
I notice there are no transmissions of 1080p (progressive scan), only 1080i.

Is a TV that does 1080p doing the scan sequence on its own frame buffer, meaning there is no difference in the transmitted information content, only the ways the TV presents it?

My understanding (or not) is there can be some motion shift (feathering, combing, line twitter, flicker) in the two interlaced scans and the progressive scan avoids this by presenting a frame as a film projector does. This would seem to need some interpolation smarts in the receiver and a faster scan rate to turn an "i" into a "p" scan sequence.
You will notice PQ differences with the 1080p versus 1080i. Your an early adopter so you must be patient. You have to wait until 1080p grows in popularity. Eventually broadcasters will use it, but I can't tell you when.
 

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RCinFLA said:
I notice there are no transmissions of 1080p (progressive scan), only 1080i.

Is a TV that does 1080p doing the scan sequence on its own frame buffer, meaning there is no difference in the transmitted information content, only the ways the TV presents it?

My understanding (or not) is there can be some motion shift (feathering, combing, line twitter, flicker) in the two interlaced scans and the progressive scan avoids this by presenting a frame as a film projector does. This would seem to need some interpolation smarts in the receiver and a faster scan rate to turn an "i" into a "p" scan sequence.
Let's simplify things. You would need to be the bionic man to notice the difference between 1080i and 1080p.
 

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mocciat said:
Let's simplify things. You would need to be the bionic man to notice the difference between 1080i and 1080p.
Well I don't have a set yet with 1080p, so I will let you tell me.:lol:
 

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RCinFLA said:
I notice there are no transmissions of 1080p (progressive scan), only 1080i.

Is a TV that does 1080p doing the scan sequence on its own frame buffer, meaning there is no difference in the transmitted information content, only the ways the TV presents it?

My understanding (or not) is there can be some motion shift (feathering, combing, line twitter, flicker) in the two interlaced scans and the progressive scan avoids this by presenting a frame as a film projector does. This would seem to need some interpolation smarts in the receiver and a faster scan rate to turn an "i" into a "p" scan sequence.
If your tv deinterlaces the signal correctly there should be no difference in the picture you receive whether getting the signal in 1080i or 1080p.

http://hometheatermag.com/hookmeup/0506halfrez/
 

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Actually, you don't need to be a bionic man if the set is big enough or you are standing close enough. Under 60", I don't think you can see the difference if you view it from 20 ft away. For me, I only want it for the "cool" factor. I almost bought one last year and probably will get one next year.

The ATSC standard only specifies up to 1080i. There is no broadcasting standard for 1080p. For old analog set, like my 6 year old CRT rear projection set, it scans 540 lines per 1/60 second. It is interlaced to 1080 lines with every two scans. Most newer sets, such as my 10 months old DLP, are digital. There isn't really an "interlaced" concept. They are all progressive because every pixel will have a color value in the video memory buffer. Up until last year, most production volume HD panels are 720p. They can receive 1080i signals but they still display them in 720p. (I'll skipping some details, as many sets actually have more than 720 lines of pixels.) That is more than the 540 scans I get on my old CRT projection set, but my old set can display 1080 lines, whereas my new 720p DLP can only display 768 lines.

To produce 1080 lines, the vendors who uses digital technology (such as Plasma, LCD, DLP) can only do 1080p. They will upconvert 1080i to 1080p. Since their existence, there has been talked about 1080 source. I don't see that happening soon, as it will take bandwidths, additional investment, and all. It is more likely that 1080p source may appear in stuff like HD DVD or Blue-ray disc players.

The resolution line is not the only factor to consider for picture quality. You need to consider viewing angles, contrast ratio, brightness, response time, color fidelity, etc. I think my 720p Sammy looks way better than 1080i Toshiba. Now, if I can afford a LED backlight, 1080p direct view LCD panel, I'd be happy. Dreaming about things I don't need but want desperately is a bad habit, isn't it?
 

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Legend
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cybrsurfer said:
You will notice PQ differences with the 1080p versus 1080i. Your an early adopter so you must be patient. You have to wait until 1080p grows in popularity. Eventually broadcasters will use it, but I can't tell you when.
First off it will be a very long time (if ever) before any of the major networks broadcast anything in 1080P. There is not enough bandwidth in the ATSC spec to do [email protected] using MPEG2. MPEG4 is not yet a part of the ATSC spec, nor would any HDTV with a built in tuner be able to use a signal broadcast in MPEG4. The only 1080P sources we will have any time soon are HD-DVD and Blu-Ray.

As for any visible difference between 1080i and 1080P, for all films and most scripted TV shows that are shot at 24fps, there is zero difference between properly de-interlaced 1080i and 1080P. Zero. 1080i draws the full 1080 scan lines every 30th of a second. If the source is 24fps then all the data that exists in the signal is being displayed. The only time 1080P would be better is on 60fps material, of which there currently is none other than the PS3 and Xbox 360.
 

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Cool Member
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Don't get caught up in the holiday hype of 1080p tv's...Save your $$$.
 

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Legend
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cybrsurfer said:
You will notice PQ differences with the 1080p versus 1080i. Your an early adopter so you must be patient. You have to wait until 1080p grows in popularity. Eventually broadcasters will use it, but I can't tell you when.
Sorry, I couldn't resist -- we cannot seem to get 1080i right (D*TV and E* HD-LITE, broadcasters "multi-channel", etc. ) and you are expecting 1080p broadcasts???? :lol:
 

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AllStar
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f300v10 said:
First off it will be a very long time (if ever) before any of the major networks broadcast anything in 1080P. There is not enough bandwidth in the ATSC spec to do [email protected] using MPEG2. MPEG4 is not yet a part of the ATSC spec, nor would any HDTV with a built in tuner be able to use a signal broadcast in MPEG4. The only 1080P sources we will have any time soon are HD-DVD and Blu-Ray.

As for any visible difference between 1080i and 1080P, for all films and most scripted TV shows that are shot at 24fps, there is zero difference between properly de-interlaced 1080i and 1080P. Zero. 1080i draws the full 1080 scan lines every 30th of a second. If the source is 24fps then all the data that exists in the signal is being displayed. The only time 1080P would be better is on 60fps material, of which there currently is none other than the PS3 and Xbox 360.
Actually, only Blu-Ray has 1080p. HD-DVD can only do 1080i.
 

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dezufnoC said:
Don't get caught up in the holiday hype of 1080p tv's...Save your $$$.
I see from your signature that you have a Sony KDF-42WE655 (720P). I have one too and its a great TV. I picked it because in my opinion when I purchased the TV it had the best HD and SD picture of any set in the showroom.

About a month ago I purchased a Sony KDL-46V2500 (1080P). I know there are no 1080p broadcasts, but in a side by side comparison, the 1080p set does a much better job of displaying both HD and SD. The picture is noticeably sharper and more enjoyable to watch.

Don't knock the new 1080p TVs until you have seen one.
 

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Legend
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f300v10 said:
No, the second generation XA-2 Toshiba will have 1080P output, and all HD-DVD disks to date are 1080P on the disk.
Also the Xbox 360 with the add-on HD-DVD drive can do 1080p using a VGA cable (only up to 1080i using component).
 

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AllStar
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Nice article... really goes in depth about the 1080p issues. Makes me happy that I've got one my self.

I'll just say this, I have my Xbox 360 connected through a vga cable, so its able to create 1080p content, and I recently got the HD-DVD add-on. You can tell a huge difference in quality in terms of detail but the image it self, from a distance, is nearly identical (Compared with 1080i resolution). But you can notice things that you normally wouldnt see, even in the movie theater (IE. grain on wood lol).

1080p is what it is, the highest resolution available. :D
 

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cybrsurfer said:
You will notice PQ differences with the 1080p versus 1080i. Your an early adopter so you must be patient. You have to wait until 1080p grows in popularity. Eventually broadcasters will use it, but I can't tell you when.
HDNet is starting to record in 1080p - though they can not broadcast in that yet
 

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Reggie3 said:
HDNet is starting to record in 1080p - though they can not broadcast in that yet
Thanks for the info.
 

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Legend
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GeoffQ said:
1080p is an ATSC spec just the 24fps variant.
I believe the 1080p/30fps is also.

The problem then becomes the bandwidth requirements to transfer so much data:

* 720p60: 1280×720 gives 0.92 megapixels per frame. If we take a 24-bit color value per pixel (RGB), this means 2.76 MB data per frame, which multiplied with the 60fps gives 1.3 Gbps or 165 MB/s.

* 1080i60: 1920×1080 means a 2 megapixel frame which translates into 6.2MB per frame. The interlacing cuts the bitrate in half: 6.2MB x 60 / 2 = 1.49 Gbps or 186 MB/s.

* 1080p60 is obviously double the throughput of 1080i: 2.98 Gbps or 373 MB/s

source
 

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