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loft3
Mar 28, 2007, 10:23 PM
All my iTunes videos with resolutions of 640x480 (regular old TV resolution as far as I know) play thru AppleTV on my standard-def (non-widescreen) TV with black bars on the left and right side of the screen? Video bought from iTunes and video encoded by me both do this.

It's very frustrating, I thought 640x480 resolution would take up the whole standard def TV area - just like watching normal TV does.



MacinJosh
Mar 28, 2007, 10:39 PM
All my iTunes videos with resolutions of 640x480 (regular old TV resolution as far as I know) play thru AppleTV on my standard-def (non-widescreen) TV with black bars on the left and right side of the screen? Video bought from iTunes and video encoded by me both do this.

It's very frustrating, I thought 640x480 resolution would take up the whole standard def TV area - just like watching normal TV does.

That's because ATV doesn't support 4:3 TVs like yours. When 4:3 material is displayed on a widescreen TV, black bars are added to the sides as in your case. Since ATV thinks it's hooked up to a widescreen TV, it adds the bars even though it shouldn't. Everything looks a bit squished (narrowed) too when watching the ATV, right?

One solution is to find out if your TV, although non-widescreen, can simulate a widescreen TV. It would then add black bars to the top and bottom of the screen when using ATV. The problem with that is going to be that you get black bars on the sides and top and bottom when watching 4:3 material unless your TV has a zoom function. You're pretty much ***** out of luck. Apple never meant ATV to work on 4:3 TVs. Even though it displays a picture on your TV, it's most likely squished, not of the correct aspect ratio.

Joshua.

Carrot007
Mar 29, 2007, 04:40 AM
In theory if you can change the apect ratio of the 4:3 material to 16:9 they would play fine on a 4:3 tv.

I do not know if there is an easy way to do this though!

eXan
Mar 29, 2007, 04:48 AM
All my iTunes videos with resolutions of 640x480 (regular old TV resolution as far as I know) play thru AppleTV on my standard-def (non-widescreen) TV with black bars on the left and right side of the screen? Video bought from iTunes and video encoded by me both do this.

It's very frustrating, I thought 640x480 resolution would take up the whole standard def TV area - just like watching normal TV does.

The resolution of the "old" TVs is 720x480 (NTSC) and 720x576 (PAL), so even if you have NTSC, the horizontal side is not long enough, though the vertical fits fine. Thats why the black bars on the sides.

OttawaGuy
Mar 29, 2007, 05:25 AM
The resolution of the "old" TVs is 720x480 (NTSC) and 720x576 (PAL), so even if you have NTSC, the horizontal side is not long enough, though the vertical fits fine. Thats why the black bars on the sides.

Correct
http://upload.wikimedia.org/wikipedia/en/thumb/9/98/Common_Video_Resolutions.svg/700px-Common_Video_Resolutions.svg.png

sycho
Mar 29, 2007, 08:08 AM
The resolution of the "old" TVs is 720x480 (NTSC) and 720x576 (PAL), so even if you have NTSC, the horizontal side is not long enough, though the vertical fits fine. Thats why the black bars on the sides.

No, incorrect, the sidebars are because the AppleTV is meant only for 16:9 TV's.


NTSC being 720x480 means nothing because there is not a set number of horizontal lines in a NTSC set. The use of 720(x480) in the digital world was just because that worked the best.

Think about it like this, the vertical lines are discrete, while horizontal lines are interpolated from the analog signal.

MacinJosh
Mar 29, 2007, 09:26 AM
No, incorrect, the sidebars are because the AppleTV is meant only for 16:9 TV's.


NTSC being 720x480 means nothing because there is not a set number of horizontal lines in a NTSC set. The use of 720(x480) in the digital world was just because that worked the best.

Think about it like this, the vertical lines are discrete, while horizontal lines are interpolated from the analog signal.

Quite right. I guess they didn't bother reading my previous response where I think I made myself pretty clear on the matter.

Joshua.

ftaok
Mar 29, 2007, 12:15 PM
Quite right. I guess they didn't bother reading my previous response where I think I made myself pretty clear on the matter.

Joshua.Not saying who's wrong or who's right (the OP will need to take a photo before the real cause can be diagnosed). If it is indeed because the aTV isn't designed for a 4:3 TV and sending out a "squished" picture, then why would there be black bars on the sides? The OP didn't mention anything about the picture being squished.

ft

bigbossbmb
Mar 29, 2007, 12:46 PM
NTSC being 720x480 means nothing because there is not a set number of horizontal lines in a NTSC set. The use of 720(x480) in the digital world was just because that worked the best.

Not just that... but Standard NTSC 720x480 has a .9 pixel aspect ratio which means the pixels are slightly taller than they are wide. 720x480 with a .9 pa is the same as 640x480 with square pixels (which is what computers use).

MacinJosh
Mar 29, 2007, 01:42 PM
Not saying who's wrong or who's right (the OP will need to take a photo before the real cause can be diagnosed). If it is indeed because the aTV isn't designed for a 4:3 TV and sending out a "squished" picture, then why would there be black bars on the sides? The OP didn't mention anything about the picture being squished.

ft

I based my "assumption" on other cases where users have reported squished images on 4:3 TVs using the ATV. It's quite obvious at this point that the ATV does not support 4:3 and does not allow a user to configure the ATV for a 4:3 like DVD players do. Therefore, the only logical explanation for the black bars on the sides is exactly what I have said so far.

Joshua.

Avatar74
Mar 29, 2007, 01:43 PM
No, incorrect, the sidebars are because the AppleTV is meant only for 16:9 TV's.

You have this backwards. When a 4:3 aspect signal (e.g. 480p) is fed to a 16:9 TV, vertical matte bars are added to make the 4:3 frame fit the 16:9 TV, not the other way around.

NTSC being 720x480 means nothing because there is not a set number of horizontal lines in a NTSC set. The use of 720(x480) in the digital world was just because that worked the best.

Think about it like this, the vertical lines are discrete, while horizontal lines are interpolated from the analog signal.

Nope. Original poster was right.

First, let me point out that while CRT displays do not have a "native resolution" to speak of in digital terms, LCD, Plasma, DLP and LCoS do.

Second, it's not the display resolution that's relevant here. It's the resolution of the INPUT SIGNAL from the file, and the OUTPUT SIGNAL from AppleTV that drive this issue.

More specifically, it's the RATIO of the input resolution of the content (H.264, etc.) to the output resolution of the player (AppleTV).

So you've got this 640x480 file playing through AppleTV. AppleTV has, let's say, been configured for 480p in the setup. 480p means the AppleTV output signal is 720x480. The content being fed through AppleTV being smaller than the output resolution means that AppleTV will send a signal that inherently has some vertical matte bars.

Regardless of how a 480p display might distort/stretch/squish the signal to fit its actual native display resolution, the vertical matte bars are IN the output signal sent to the TV just as horizontal matte bars on anamorphic DVD's are added by the DVD player in the output signal sent to a 4:3 TV.

sandman42
Mar 29, 2007, 01:49 PM
You have this backwards. When a 4:3 aspect signal (e.g. 480p) is fed to a 16:9 TV, vertical matte bars are added to make the 4:3 frame fit the 16:9 TV, not the other way around.

You're both right. The :apple:TV thinks it's sending its signal to a 16:9 tv, because that's all it was intended to work with. When you view this on a 4:3 tv, you still see the black bars, because the 4:3 tv doesn't crop them out, it compresses the image horizontally to show the whole thing, including the bars.

MacinJosh
Mar 29, 2007, 01:57 PM
You're both right. The :apple:TV thinks it's sending its signal to a 16:9 tv, because that's all it was intended to work with. When you view this on a 4:3 tv, you still see the black bars, because the 4:3 tv doesn't crop them out, it compresses the image horizontally to show the whole thing, including the bars.

Exactly. Can we all now agree on this? I'm sure the OP got the answer he was looking for.

Joshua.

ftaok
Mar 29, 2007, 01:59 PM
I based my "assumption" on other cases where users have reported squished images on 4:3 TVs using the ATV. It's quite obvious at this point that the ATV does not support 4:3 and does not allow a user to configure the ATV for a 4:3 like DVD players do. Therefore, the only logical explanation for the black bars on the sides is exactly what I have said so far.

Joshua.

OK, after reading this and sandman's post, I went back and re-read the original post. This time, I picked up on the fact that he's watching 4:3 material on the aTV, which is sending out a 16:9 output back onto 4:3 TV. Therefore, I would expect the picture to have black bars on the sides AND to be squished.

I think I'm on the right page now. Thanks.

Multimedia
Mar 29, 2007, 02:01 PM
All my iTunes videos with resolutions of 640x480 (regular old TV resolution as far as I know) play thru AppleTV on my standard-def (non-widescreen) TV with black bars on the left and right side of the screen? Video bought from iTunes and video encoded by me both do this.

It's very frustrating, I thought 640x480 resolution would take up the whole standard def TV area - just like watching normal TV does.You know the :apple:TV was never intended to be used on a 4x3 set yet you insist it should. Get over it Loft3, get rid of your obsolete 4x3 piece of analog crap and buy an ATSC HDTV For $499 at Costco like a real red blooded American consumer should. :eek: :rolleyes: :D

Analog TV blows and the sooner you hook up an off air antenna like a Terk TV5 to an ATSC Tuner in a HDTV the better off you're gonna be. Can we Please Stop Hanging on to the past people!! Analog TV is DEAD in 22 months. The sooner you face reality the better.

That's why :apple:TV don't work with crap analog 4x3 sets (bad grammar for dramatic purposes). If Apple wanted to hang on to the past they would have made it work with the past. But they don't cause they have vision. So follow the leader and lose the crap TVs please.

gkarris
Mar 29, 2007, 02:14 PM
You know the :apple:TV was never intended to be used on a 4x3 set yet you insist it should. Get over it Loft3, get rid of your obsolete 4x3 piece of analog crap and buy an ATSC HDTV For $499 at Costco like a real red blooded American consumer should. :eek: :rolleyes: :D

Analog TV blows and the sooner you hook up an off air antenna like a Terk TV5 to an ATSC Tuner in a HDTV the better off you're gonna be. Can we Please Stop Hanging on to the past people!! Analog TV is DEAD in 22 months. The sooner you face reality the better.

That's why :apple:TV don't work with crap analog 4x3 sets (bad grammer for dramatic purposes). If Apple wanted to hang on to the past they would have made it work with the past. But they don't cause they have vision. So follow the leader and lose the crap TVs please.

How am I going to watch my CED's and Beta tapes??? :rolleyes:

balamw
Mar 29, 2007, 02:45 PM
How am I going to watch my CED's and Beta tapes??? :rolleyes:

Most HDTVs still have legacy composite video inputs. :rolleyes:

B

Multimedia
Mar 29, 2007, 02:54 PM
Most HDTVs still have legacy composite video inputs. :rolleyes: Not only that. All have an analog NTSC tuner in them as well as the digital ATSC tuner. Wake Up!! :eek:

sandman42
Mar 29, 2007, 03:37 PM
(bad grammer for dramatic purposes)

What's the bad spelling for? (psst, it's "grammar").

eXan
Mar 29, 2007, 11:38 PM
You know the :apple:TV was never intended to be used on a 4x3 set yet you insist it should. Get over it Loft3, get rid of your obsolete 4x3 piece of analog crap and buy an ATSC HDTV For $499 at Costco like a real red blooded American consumer should. :eek: :rolleyes: :D

Analog TV blows and the sooner you hook up an off air antenna like a Terk TV5 to an ATSC Tuner in a HDTV the better off you're gonna be. Can we Please Stop Hanging on to the past people!! Analog TV is DEAD in 22 months. The sooner you face reality the better.

That's why :apple:TV don't work with crap analog 4x3 sets (bad grammer for dramatic purposes). If Apple wanted to hang on to the past they would have made it work with the past. But they don't cause they have vision. So follow the leader and lose the crap TVs please.

Not all analog TVs are "crap". We still have 9year+ old Sony 32" TV that shows superior color compared to new and very expensive HDTVs. Its also better to view interlaced content on the analog TVs.

Not to mention that there's no HD television here, so buying a HDTV just to watch HD trailers for apple.com is pointless. (This may be different in other countries though)

MacinJosh
Mar 29, 2007, 11:50 PM
Not all analog TVs are "crap". We still have 9year+ old Sony 32" TV that shows superior color compared to new and very expensive HDTVs. Its also better to view interlaced content on the analog TVs.

Not to mention that there's no HD television here, so buying a HDTV just to watch HD trailers for apple.com is pointless. (This may be different in other countries though)

Yeah, good analog TVs still have superior color, contrast and black levels. LCD/Plasma are getting better at that all the time and will eventually catch up to analog. OLED technology is something to watch for. It's quite amazing to see.

Oh, and to the rest of yous: Keep in mind that Analog TV will still live many years in other countries. Finland, where I'm currently living, is moving to digital-only-tv in August but it's not HDTV, and while digital, most STBs only have analog outputs to analog TVs.

Joshua.

balamw
Mar 30, 2007, 12:38 AM
Yeah, good analog TVs still have superior color, contrast and black levels.
You know there are CRTs that have HD resolution/inputs too. They're actually cheaper than LCD or plasma, but have all the same features of "standard" CRTs.

B

MacinJosh
Mar 30, 2007, 01:39 AM
You know there are CRTs that have HD resolution/inputs too. They're actually cheaper than LCD or plasma, but have all the same features of "standard" CRTs.

B

I've heard. Quite rare in europe though. I only know of one available in limited quantity in Finland and that's the Philips Cineos 32PW9551/12. It's got HDMI and all. Seems to be sold out in most places though.

Joshua.

Avatar74
Mar 30, 2007, 01:59 PM
Not all analog TVs are "crap". We still have 9year+ old Sony 32" TV that shows superior color compared to new and very expensive HDTVs. Its also better to view interlaced content on the analog TVs.

Not to mention that there's no HD television here, so buying a HDTV just to watch HD trailers for apple.com is pointless. (This may be different in other countries though)

There's a reason the Sony Trinitron has been the display reference standard for NTSC calibrated studio monitors for 40 years. :)

I have a 36" Sony WEGA Trinitron XBR HDTV and aside from minor geometry issues typical of large CRT's, the color, clarity and contrast are stellar and unmatched by even the $7000 70 inch Sony SXRD XBR 1080p.

madmaxmedia
Mar 30, 2007, 02:52 PM
I don't have an ATV, but I do have a 32" 4:3 analog Sony HDTV.

I don't think the image is being squished on the OP's experience (since he only mentions the bars.) This is what it sounds like is happening (same thing happens to me with my XBox hooked up through HDMI/DVI)-

1. The ATV signal is being output to the TV in 16:9 ratio.

2. The TV compensates for this by letterboxing the display on the top and bottom, so you see the entire 16:9 picture.

3. When ATV has 4:3 content, it compensates for this by putting black bars to the left and right of the picture, since it only outputs in 16:9.

4. The TV gets this 16:9 content, and still adds the letterbox bars. So what you get is a smaller 4:3 picture inside a larger 4:3 screen. This happens to me when I play 4:3 video files in my XBMC.

The TV is not smart enough to automatically 'zoom' the content to fill the screen- it has no way of knowing that it's actually 4:3 content with bars on the sides. Although some TVs have zoom that might help fill the screen.

Most DVD players have the option of automatically changing output if you have a 4:3 HDTV like my Sony TV. So 4:3 content is fullscreen, and 16:9 content is letterboxed (but the Sony also has a 16:9 enhanced mode that compresses the scan lines so no extra resolution is wasted on drawing black bars.)

rc86mike
Mar 30, 2007, 02:55 PM
I would love a defintive answer to this one.

I have my ATV hooked upto my TV that puts out 1080i.

I've ripped all my movies at 640x480. Some show up full screen while others show up with bars on the sides. Is this because some movies are formatted for widescreen while some are formatted for 4:3 standard aspect ratio? If so is there anyway to fix this?

Thanks!

madmaxmedia
Mar 30, 2007, 02:56 PM
You know the :apple:TV was never intended to be used on a 4x3 set yet you insist it should. Get over it Loft3, get rid of your obsolete 4x3 piece of analog crap and buy an ATSC HDTV For $499 at Costco like a real red blooded American consumer should. :eek: :rolleyes: :D

That's not remotely constructive to the OP, ya know? He only asked, and wasn't insisting or complaining.

He might not be able to afford an HDT either. Although I guess a real red-blooded American would march to Costco and put that TV on his credit card. ;) If he's a real American though, he should buy a 60" LCD, not a wimpy $500 TV... ;)

madmaxmedia
Mar 30, 2007, 03:00 PM
I would love a defintive answer to this one.

I have my ATV hooked upto my TV that puts out 1080i.

I've ripped all my movies at 640x480. Some show up full screen while others show up with bars on the sides. Is this because some movies are formatted for widescreen while some are formatted for 4:3 standard aspect ratio? If so is there anyway to fix this?

Thanks!

You need to be a lot more specific about whether the bars are top/bottom, left/right, or both. And what aspect ratio your movies are that this happens with. And what the ratio of your TV display is.

sandman42
Mar 30, 2007, 03:40 PM
I don't think the image is being squished on the OP's experience (since he only mentions the bars.) This is what it sounds like is happening (same thing happens to me with my XBox hooked up through HDMI/DVI)-

Could be. We all understand now (I hope) why there are black bars on the sides. Whether the OP's TV is 'smart' enough to recognize the 16:9 content (as presented by the :apple:TV) and preserve the aspect ratio by letterboxing, or if it displays it full screen vertically (which could be considered as stretching the image vertically rather than compressing horizontally) -- we don't know. But we can definitely explain the bars on the sides.

rc86mike
Mar 30, 2007, 03:50 PM
You need to be a lot more specific about whether the bars are top/bottom, left/right, or both. And what aspect ratio your movies are that this happens with. And what the ratio of your TV display is.

The bars are left/right NOT top/bottom. My TV ratio is currently set to widescreen (it is a widscreen display) so 16:9 viewing I assume. The movie/tv show dvd casings only state it was "made to fit your TV". None of them are the widescreen versions. Thank you :-) Hope that helps a bit.

Antares
Mar 30, 2007, 04:35 PM
The bars are left/right NOT top/bottom. My TV ratio is currently set to widescreen (it is a widscreen display) so 16:9 viewing I assume. The movie/tv show dvd casings only state it was "made to fit your TV". None of them are the widescreen versions. Thank you :-) Hope that helps a bit.

"made to fit" sounds like a full-screen dvd. "Full-Screen" dvd's are in the 4:3 format. If you rip a full-screen dvd, it will have black bars on the sides when watching it on any widescreen display. That's actually the correct way to watch "full-screen" content....with black bars on the side. Full-screen content will not magically become widescreen content on a widescreen tv (unless you stretch the image. But that image will be wrong...people will look fatter than they actually are, circles will look like ovals, squares will look like rectangles, etc.)

StealthRider
Mar 30, 2007, 04:59 PM
The :apple:TV has the option for 480i output, so that is not the problem. The problem is that there's a difference between a TV's 720x480 resolution and the 640x480 of the content, as someone said earlier.

madmaxmedia
Mar 30, 2007, 05:01 PM
Right, that's another possible complication. So it's also possible that there are only bars on left and right, and the image is stretched vertically.

I am guessing that as long as your TV is 16:9 'aware', then you'll get a good picture from ATV. It just may have unnecessary bars on all sides if its 4:3 content, but that's pretty much unavoidable.

Could be. We all understand now (I hope) why there are black bars on the sides. Whether the OP's TV is 'smart' enough to recognize the 16:9 content (as presented by the :apple:TV) and preserve the aspect ratio by letterboxing, or if it displays it full screen vertically (which could be considered as stretching the image vertically rather than compressing horizontally) -- we don't know. But we can definitely explain the bars on the sides.

rc86mike
Mar 30, 2007, 08:15 PM
Just a quick update. I've been doing some tests this afternoon (I had today off work woohoo!) and I found that some DVD's I put into Handbrake allow me to output at 720x480 which results in a full widescreen picture while some dvd's will only let you output upto 640x480 which result with black bars on the right and left sides. It's not too big of deal really, just thought I'd share.

One other interesting note I found while ripping 40 Year Old Virgin was that it let me output to 720x480 but I opted for the test to go 640x480 but it still filled my whole widescreen display.

So by putting two and two together it seems that if the dvd will ALLOW you to output to 720x480 but you choose to go lower at 640x480 it will still fit it to the widescreen display. Interesting. Anyone else more about this?

MacinJosh
Mar 30, 2007, 11:27 PM
Just a quick update. I've been doing some tests this afternoon (I had today off work woohoo!) and I found that some DVD's I put into Handbrake allow me to output at 720x480 which results in a full widescreen picture while some dvd's will only let you output upto 640x480 which result with black bars on the right and left sides. It's not too big of deal really, just thought I'd share.

One other interesting note I found while ripping 40 Year Old Virgin was that it let me output to 720x480 but I opted for the test to go 640x480 but it still filled my whole widescreen display.

So by putting two and two together it seems that if the dvd will ALLOW you to output to 720x480 but you choose to go lower at 640x480 it will still fit it to the widescreen display. Interesting. Anyone else more about this?

Neither 640x480 or 720x480 is a widescreen resolution when viewed on TVs or monitors. 720/480 = 1.5 and 640/480 = 1.33 (4:3). If you want to use 720 wide DVD rips I suggest the following:

720x400 for 16:9 material (Should fill the whole 16:9 TV screen with no bars)
720x304 for 2.35:1 material (Should have black bars on top and bottom on 16:9 TVs)

As to why a 640x480 video fills your TV, must be due to your TVs settings that handle aspect ratios and zooming/stretching. Some TVs can sense black bars on images and zoom or stretch the image to get rid of them. You'd have to RTFM (read the effing manual) to find out.

Joshua.