HD ready and Full HD

Quantum Theory said:
Not true. With 1080i two consecutive frames are carried in the 1920 x 1080 resolution (normally at about half the frame rate of a progressive image). Each alternate line belongs to a different frame. When the image is static these 2 consecutive frames are used to build a full 1080p image. As soon as that image starts moving, this can't be done and the resolution drops to 1920 x 540, because line doubling is used during de-interlacing. Saying that both 1080i/p is the same resolution is completely wrong. Had this whole argument with another guy in another thread recently.
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Yes, it takes two consecutive 1080i frames to make a full 1920x1080 frame, however it's normally shown at double the frame rate or the same frame rate of a progressive frame. You don't get 25i - only 50i, as each field is shown in succession to generate a complete image.
De-interlacing does result in quality loss as you say - maybe I wasn't as clear as I should've been - hence why I said progressive frames have numerous advantages over the interlaced counterpart.
 
genetic said:
Yes, it takes two consecutive 1080i frames to make a full 1920x1080 frame, however it's normally shown at double the frame rate or the same frame rate of a progressive frame. You don't get 25i - only 50i, as each field is shown in succession to generate a complete image.
De-interlacing does result in quality loss as you say - maybe I wasn't as clear as I should've been - hence why I said progressive frames have numerous advantages over the interlaced counterpart.
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After de-interlacing, the frame rate is the same... before de-interlacing it is running at half the frame rate.

Read this... All of it.

http://www.bluesky-web.com/numbers-mean-little.htm

For sport with constant fast moving images, 720p rules 1080i. I believe SSHD is actually running 720p, despite what wiki and FB says. Will make sure tomorrow...
 
Quantum Theory said:
Saying that both 1080i/p is the same resolution is completely wrong.
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Well it all depends where in the signal path you refer to.

Irrespective of input signal, all digitial output devices (LCD/LED/Plasma etc.) display in progressive scan. That is they update the panel's pixels left to right & top to bottom at the prevailing display refresh rate (in Hz or times per sec) from device's frame buffer (RAM).

So even with interlaced input the device is still updating panel's even & odd lines on each cycle. What results is that at any point in time either the odd or even lines should be a few milliseconds old (stale), but this is where motion compensation circuitry intervenes (e.g. Samsung's MotionPlus or Sony's MotionFlow).

Based on all the data in the frame buffer the motion circuitry interpolates (basically guesses) what stale lines should be like and alters them together with the incoming source updates at that instant of time.

So yes a progressive input is more accurate as there is no guesswork involved, but strictly both 1080p & 1080i images are progressively displayed at 1920x1080 resolution.

As indicated in a previous post, I cant percieve noticable difference in motion performance when switching my HDPVR between the 720p & 1080i settings.
 
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Roman4604 said:
So yes a progressive input is more accurate as there is no guesswork involved, but strictly both 1080p & 1080i images are progressively displayed at 1920x1080 resolution.
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With moving 1080i images, even with good image processing, the 1920 x 1080 resolution you talk about would really be an upscaled 1920 x 540 image.
 
Quantum Theory said:
With moving 1080i images, even with good image processing, the 1920 x 1080 resolution you talk about would really be an upscaled 1920 x 540 image.
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No, the frame buffer matches the native resolution of the panel, meaning it containts the information for all 1080 lines. Its just at an instant of time half the lines are slightly out of date. Not quite the same as constant upscaling where you only have 540 lines of info from source.
 
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Roman4604 said:
No, the frame buffer matches the native resolution of the panel.
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Uhmmm... How? Only half the lines of each 1080i frame received belongs to each frame displayed after de-interlacing. I know that the image processor will try and use frames before and after to try to fill in those lines as best it can, but essentially it is upscaling a 1920 x 540 image.

Read the link I posted earlier...

http://www.bluesky-web.com/numbers-mean-little.htm
 
Quantum Theory said:
After de-interlacing, the frame rate is the same... before de-interlacing it is running at half the frame rate.

Read this... All of it.

http://www.bluesky-web.com/numbers-mean-little.htm

For sport with constant fast moving images, 720p rules 1080i. I believe SSHD is actually running 720p, despite what wiki and FB says. Will make sure tomorrow...
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Where do you get 1080i runs at half the frame rate of it's progressive cousin? It doesn't.

The frame rate can be implied by the context, while the field rate is generally specified after the letter i, such as "1080i60". In this case 1080i60 refers to 60 fields per second or 30 frames per second. The European Broadcasting Union (EBU) prefers to use the resolution and frame rate (not field rate) separated by a slash, as in 1080i/30 and 1080i/25, likewise 480i/30 and 576i/25.[1] Resolutions of 1080i60 or 1080i50 often refers to 1080i/30 or 1080i/25 in EBU notation.
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Half the frame rate of what? 720p50 or 1080p25 or 1080p50?

All cameras (besides slo-mo) shoot at either 25fps or 50fps in PAL land. Interlaced cameras shoot at 50 fields per second, so in effect they are shooting 50 half frames per second. After deinterlacing, the video is pushed out at 25 progressive fps.

SuperSport definitely broadcast at 1080i - check with your contacts ;)
 
genetic said:
Where do you get 1080i runs at half the frame rate of it's progressive cousin? It doesn't.



Half the frame rate of what? 720p50 or 1080p25 or 1080p50?

All cameras (besides slo-mo) shoot at either 25fps or 50fps in PAL land. Interlaced cameras shoot at 50 fields per second, so in effect they are shooting 50 half frames per second. After deinterlacing, the video is pushed out at 25 progressive fps.

SuperSport definitely broadcast at 1080i - check with your contacts ;)
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Guys. I do know a bit about this stuff. The interlaced image is received at 25 fps. 25 double fields. It is then de-interlaced and played back at 50 fps, but at a resolution of as low as 1920 x 540. Did any of you even read the article I posted twice now in this thread? It was written by an industry expert, not some wiki contributor or random guy on a forum.

I work with this stuff daily and know that MC uses 720p mostly... Don't even need to check with my contacts. I just want to check how often, if ever, they use 1080i for sport.

Anyway. You can keep debating on your own... I'm done :D
 
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Smurfatefrog said:
If those links are to be believed which state:
"Picture format 576i (SDTV 16:9, 4:3) 1080i (HDTV) "

Please explain where exactly Supersport broadcast SDTV 16:9 ?
I'd be more inclined to believe http://forum.dstv.com/archive/index.php/t-544.html
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SuperSport shoot in HD - which is only 16:9.

Check your decoder setting for TV aspect ratio set-up. Some SD SuperSport channels are definitely 16:9 if your decoder is set correctly.
 
Quantum Theory said:
http://www.bluesky-web.com/numbers-mean-little.htm
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Agreed, but this only looks at the situation from a source persective, he's not taking into account what is happening on the output device (manipulation/processing).

I'm not for a minute saying 1080i is in any way equal to 1080p, just that modern displays go a long way to compensate for 1080i shortcommings. For me its a tossup between negative effects of interlacing (inter-line interpolation) vs. the negative effects of not running at a panel's native resolution (upscaling on TV). I find the latter impairs the picture slightly more.

As usual each must try it for themselves i.e. 1080i vs 720p using FHD display + HDPVR.
 
Quantum Theory said:
Guys. I do know a bit about this stuff. The interlaced image is received at 25 fps. 25 double fields. It is then de-interlaced and played back at 50 fps, but at a resolution of as low as 1920 x 540. Did any of you even read the article I posted twice now in this thread? It was written by an industry expert, not some wiki contributor or random guy on forum.

I work with this stuff daily and know that MC uses 720p mostly... Don't even need to check with my contacts. I just want to check how often, if ever, they use 1080i for sport.
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I work in the industry myself. :)

I think you are referring to certain deinterlacing techniques, and not interlaced footage in general.

M-Net only broadcasts in 720p - so yes, I'm sure most of their content is 720p orientated.
 
genetic said:
M-Net only broadcasts in 720p - so yes, I'm sure most of their content is 720p orientated.
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Not sure about that (unless doesnt work as advertised?).

Switched my HDPVR2P's output setting to Original (instead of locked to 1080i or 720p) and flicked through all the HD channels. According to my TV the input signal over HDMI stayed on 1920x1080i@50Hz on all 6 HD channels (& SD for that matter).
 
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genetic said:
SuperSport shoot in HD - which is only 16:9.

Check your decoder setting for TV aspect ratio set-up. Some SD SuperSport channels are definitely 16:9 if your decoder is set correctly.
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Yes obviously HD is 16:9. Next time you see a Supersport SD channel broadcasting in widescreen drop me a PM..... the widescreen SD channel was discontinued years ago
 
genetic said:
Cameraman and editor for a production company - got to say our hours can be horrendous at times - especially with editing, being all deadline driven, but it beats the typical office job! :)

What do you do?
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RF, IF, HDMi etc system design and tech support at an equipment supplier. Some office hours involved, but I do get out a lot. Would love your job though.
 
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