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Craig M

macrumors newbie
Original poster
Mar 8, 2012
7
0
All this talk about 1080p, but no one seems to know if the device will handle conventional TV frame rates. Even the previous Apple TV @ 720p was essentially 'broken' by only being able to display source material with frame rates of 24, 25 or 30 frames per second. Even conventional broadcast TV has 50 or 60 images per second: Essential for programmes like sport or reality-type programming which need high motion rendition.

Movies are OK because they are only 24 frames per second. But I'm not talking about movie content. What if the source was shot at 50 or 60? They are effectively halving the frame rate by dropping every second frame.

Heck, even 50i or 60i would do the trick.

So, is the flavour of 1080P that Apple will serve up locked into the low frame rates? Or will they finally deliver 1080P/50 & 1080P/60?

Something tells me that this new generation of Apple TV will still be locked into 'half frame rate' HDTV. Sport will look juddery, only showing 1080P/30, ie half the frames.
 
All this talk about 1080p, but no one seems to know if the device will handle conventional TV frame rates. Even the previous Apple TV @ 720p was essentially 'broken' by only being able to display source material with frame rates of 24, 25 or 30 frames per second. Even conventional broadcast TV has 50 or 60 images per second: Essential for programmes like sport or reality-type programming which need high motion rendition.

Movies are OK because they are only 24 frames per second. But I'm not talking about movie content. What if the source was shot at 50 or 60? They are effectively halving the frame rate by dropping every second frame.

Heck, even 50i or 60i would do the trick.

So, is the flavour of 1080P that Apple will serve up locked into the low frame rates? Or will they finally deliver 1080P/50 & 1080P/60?

Something tells me that this new generation of Apple TV will still be locked into 'half frame rate' HDTV. Sport will look juddery, only showing 1080P/30, ie half the frames.

From Apple's website:

Video Formats


H.264 video up to 1080p, 30 frames per second, High or Main Profile level 4.0 or lower, Baseline profile level 3.0 or lower with AAC-LC audio up to 160 Kbps per channel, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats

MPEG-4 video up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats

Motion JPEG (M-JPEG) up to 35 Mbps, 1280 by 720 pixels, 30 frames per second, audio in ulaw, PCM stereo audio in .avi file format


GL
 
So much for watching The Hobbit in 48 fps. :( I wonder if it handles 3D movies?
 
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All this talk about 1080p, but no one seems to know if the device will handle conventional TV frame rates. Even the previous Apple TV @ 720p was essentially 'broken' by only being able to display source material with frame rates of 24, 25 or 30 frames per second. Even conventional broadcast TV has 50 or 60 images per second: Essential for programmes like sport or reality-type programming which need high motion rendition.

Movies are OK because they are only 24 frames per second. But I'm not talking about movie content. What if the source was shot at 50 or 60? They are effectively halving the frame rate by dropping every second frame.

All of the HD sports or reality tv programming you've seen was shot in either 1080i (59.94 interlaced frames per second), 1080p (29.97 progressive frames per second), or 720p (29.97 frames per second). Calling the AppleTV2's 720p framerate "broken" is misguided. You've always been watching a variant of 30fps material, whether that be 30 sequential frames or 60 interlaced frames.

Of course some cameras now are shooting higher framerates progressively, but in the broadcast realm nothing has been distributed that way. We've only gotten the ones above. Of course this could all change down the road, but it will have no effect on how you've watched or are currently watching that material at this point.
 
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Sorry to disagree with you, but even old interlaced TV produces 50 or 60 unique images every second. Not 25 or 30. And the Apple TV can't even do this even though broadcast TV is over 50 years old.
 
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Sorry to disagree with you, but even old interlaced TV produces 50 or 60 unique images every second. Not 25 or 30. And the Apple TV can't even do this even though broadcast TV is over 50 years old.

I'm sorry too. Old interlaced television was 60 fields per second. Each field contained every other line. You got all the even lines in one field, then you got all the odd lines in the next field. The persistence of the phosphor on the screen held the fields on the screen long enough so that they blended into a single picture. You received 30 full frames every second.

A.
 
I'm sorry too. Old interlaced television was 60 fields per second. Each field contained every other line. You got all the even lines in one field, then you got all the odd lines in the next field. The persistence of the phosphor on the screen held the fields on the screen long enough so that they blended into a single picture. You received 30 full frames every second.

A.

Correct, I think people get confused with the interlaced and progressive definition. The best way I can think of to explain it is going back a way to the old CRT monitor day's....The lower end GPU's all used the interlaced system which sort of "fooled" your eyes into seeing more than was actually there. The progressive scan is not new, certainly not on our Mac's or modern PC graphics cards...It's just that TV production companies etc. have not implemented it...I have an 8 year old LCD TV in my bedroom which is P capable, and somewhere in a cupboard a really old HDD / DVD recorder which is also "P" capable.

In the UK if you don't fork out megabucks for subscription cable TV etc., very few programmes are true HD 1080p. My smart TV is technologically miles ahead of what is actually being produced. Upscaling 720 is not going to result in instant "Wow" factor difference. Off hand the only UK show I watch that IS shot in true HD is Top gear. If you watch the two versions together (they air at the same time on the standard BBC channel, and the HD BBC) the difference is staggering.

Pin sharp on the HD and even on the best TV set, the difference is outstanding.

I've ordered the new ATV to replace my 2, but primarily I'm not expecting premium quality content to appear quickly. Over time it will, and the more it does, the more people are going to insist on the high quality format.
 
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Sorry to disagree with you, but even old interlaced TV produces 50 or 60 unique images every second. Not 25 or 30. And the Apple TV can't even do this even though broadcast TV is over 50 years old.

You can disagree, but you're still wrong. As others have mentioned you see 50 or 60 fields per second, not full frames.

interlce.jpg
 
You can disagree, but you're still wrong. As others have mentioned you see 50 or 60 fields per second, not full frames.

Image

No, I'm not. 50i and 60i can have these odd and even lines sourced from DIFFERENT points in time. Even though only odd lines are 'drawn' in the first pass, and the even lines are 'drawn' in the second pass, an object may have moved within camera frame in that time, meaning that if you weave the fields back together to form a 'progressive' image, you'll get combing. The lines won't match up to form a smooth image. There'll be 'jaggies'.

Yes, there has been movement between the time the first field was captured, and the second. Presto, 50 or 60 unique images per second! 50 year old interlaced broadcast TV HAS been able to produce 50 or 60 unique images per second.

The Apple TV can only do max 30p. Not 50P/60P or even 50i/60i.

Let your eyes be the judge. Broadcast TV, like the news, is 1080/60i or 720/60p. Smooth motion. Not juddery 30p or less. Even old NTSC is 480/60i* (When referring to 60Hz, it is of course actually 59.94).
 
I always though 30 WAS 60 and 25 WAS 50 or the equivalent

blurays are always juddery on atv because it cant output 24p.
 
We don't know that the ATV3 can't play back 50i/60i -- when the specs talks about 1080p30 as a maximum it's talking about frames rather than fields. They're also talking about (if conservatively) the limitations of the video decoder -- and 1080i60 shouldn't be much more difficult to decode than 1080p30 since they have basically the same number of pixels.

The specs suggest that the ATV3 will output at 1080p50 or 1080p60. It may also output 1080i50 and 1080i60 like the ATV1 did. I'm still hoping that it will also output at 1080p24, now or in the future, but we'll have to wait and see. In any case, there's more scope for a TV or video processor to recover 1080p24 from 1080i60 or 1080p60 than there is from 720p60.
 
Yes, there has been movement between the time the first field was captured, and the second. Presto, 50 or 60 unique images per second! 50 year old interlaced broadcast TV HAS been able to produce 50 or 60 unique images per second.

I must be misinterpreting your definition of "unique." You could certainly say that 1 frame of interlaced material is unique, but that doesn't negate the fact that 1/60th of a second (NTSC) of interlaced video is only representative of half of the resolution of the entire 1920x1080 frame. You're only getting 1 field at a time. Of course this happens so fast and your eyes can't see the difference, but 1 60fps of interlaced video is vastly different from 1 60fps of progressive. And no one broadcasts the latter at this point.
 
Question still stands: does the new Apple TV do 60i?

Forget all the technical chatter. The old Apple TV has a very poor rendition of 60i content. Some TV shows are hard to watch on the old Apple TV. Others are better, but still quite choppy. Movies are no problem, but try watching some shows made for TV.

Does the new Apple TV handle 60i content properly?
 
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