1440x1080 is 16:9? at DVinfo.net

Jan Zirn · September 21st, 2005, 02:00 AM

Hi All,

I think I missed something on this obviously great cam:

In the specs it says that the XL H1 records in 16:9 HD with 1080 lines. For me this means, it needs 1920 columns to achieve this. But Canon USA says on their web page that it only has 1440, which is rather a 4:3-format.

How do they get to 1920? Ist this this horizontal pixelshift thing? So they basically "calculate" a full 1080x1920 picture from two 1440x1920 pics? Or how does it work?

Sorry, if this question sounds stupid, but I did not find an answer anywhere...

Thx
Jan
(from Germany)

Martin Mayer · September 21st, 2005, 04:54 AM

The pixels aren't displayed as square? (Like all SD video pixel formats as well: none of them is square. They're rectangles!)

Jan Zirn · September 21st, 2005, 05:08 AM

Hi Martin,

thx for the answer.

This means, with the XL H1 we won't get the full 1080x1920, even if we have a 1080x1920 display (I haven't seen those yet for retail customers, but they will be coming...). mmmhhh only an interpolated picture.

This is kind of sad, isn't it?

Thanks anyway

Jan

Martin Mayer · September 21st, 2005, 05:18 AM

Well, you will get a full screen display, if the display driver is correctly transforming the HDV into the correct aspect ratio: it will broaden the pixels to cover the full 1920 pixels across the display.

Display drivers already do this when displaying SD video on square pixel (e.g. computer LCD) displays. e.g. in SD, 4:3 PAL is 720x576 pixels, which need to be stretched out wider to fill 768x576 to reach the correct 4:3 ratio on a square pixel display.

Jan Zirn · September 21st, 2005, 05:48 AM

Hi Martin,

sure the display won't show black pixels it's borders.

What I ment was, that there would be some kind of interpolation within the camera as it's 1440 horizontal pixels must somehow fit into the 1920 pixels of the display (by means of interpolation).

So some "neighbor pixles" will always be the same = loss of detail compared to a real 1080x1920 picture.

This is, what I think is sad for such a highend piece of technology...

Pete Bauer · September 21st, 2005, 06:09 AM

Perhaps it is just a slight bit premature to feel sad? None of us has used the camera yet or seen the picture it will be able to produce. Full native 1920x1080 is still very high-dollar stuff. My understanding is that even many of the professional HD cameras have used either the same 1440x1080, or 1280x1080 (DVCProHD), and stretched the pixels to get 1920x1080. So based on the raw pixel count by itself, I don't think there is cause for disappointment quite yet. For more info, see this post by Thomas Smet:

http://www.dvinfo.net/conf/showpost....2&postcount=18

in this thread:

http://www.dvinfo.net/conf/showthread.php?t=51177

Personally, I feel more like a kid in a candy store to see cameras costing under $10k US go from 720x480 with 4:1:1 to either 1440x1080 with 4:2:0 (H1 HDV), 1440x1080 with 4:2:2 uncompressed (H1), or 1280x1080 (HVX200) with 4:2:2. These new cameras will have at least FOUR times the resolution of DV. And raw pixel counts aren't the whole story. Among many factors, the lens, the signal processing, and the recording format all play large roles in what the eye finally sees. I'm excited about the choices we will soon have!

Jan Zirn · September 21st, 2005, 06:22 AM

I fully agree on the "kid in the candy store" ;-)) and I hope you did not get me wrong. I own a XL1s for 3 years now and I still think it's a good piece.

Of course the XL H1 will be a biiiiiiiiiiig step forward compared to the XL1s (not to mention the XL2, which I never tried so far, to be honest). But, as I learned now, it's not a true 1080x1920 cam (which I thought it was).

OK, this does NOT mean, it's not worth the money. In fact: I cannot make a judgment on this as I havn't seen it so far (of course;-)). And you are absolutly right there are many other features that determine the final quality of the output.

I only worry a bit about someting completely different: That is that users will get problems with picture sharpness. Especially when filming moving stuff, free hand with auto-focus (I know, most people here prefer not to use the autofocus...). Canons always used to be a little on the "soft side" in AF mode, which may be only noticeable for the expert on standard definition (my parents never saw it ;-))).

But on HD?? mmhhh... I hope it's different this time.

Regrads
Jan

Steve House · September 21st, 2005, 06:28 AM

There's *image* aspect ratio, *pixel* aspect ratio, and image pixel count or resolution. The pixel count in the high def HDV image is 1440x1080. The pixels themselves are rectangular, wider than they are high, in the proportion of 1.333:1. Multiplying 1440*1.333 gives you 1920 for a 16:9 aspect ratio HDV screen size of 1920:1080.

I see you're in Bad Nauheim - I have family both there and next door in Friedberg!

Jan Zirn · September 21st, 2005, 07:25 AM

Hi Steve,

thanks for your help.

Yeahh, famous Bad Nauheim, where Elvis the King used to live when he was in the Army ;-)) (and did his service in Friedberg, which is only 2 mls away from Bad Nauheim).

The world is so small ;-)) Do your folks work for the Army? Unfortunatly I have no real contacts to army personel, as they also live quite separated from us Germans in their guarded living areas. (sad, but after 9/11, I really can understand all those security measures... I would do the same).

Please say "hello" to your relatives from a German guy that lives "next door" and still very much likes to come to North America (unlike some other Germans). So far I have only seen L.A. (my brother lives there) and NY, never been to Canada. But one day... ;-))

Have a good day in Canada!!!

Best regards
Jan

Chris Hurd · September 21st, 2005, 08:46 AM

Pixel aspect ratio, and how 1440 becomes 1920, explained here:

http://www.dvinfo.net/canonxlh1/articles/article06.php

Steve House · September 21st, 2005, 11:06 AM

Quote:

Originally Posted by Jan Zirn

Hi Steve,

thanks for your help.

Yeahh, famous Bad Nauheim, where Elvis the King used to live when he was in the Army ;-)) (and did his service in Friedberg, which is only 2 mls away from Bad Nauheim).

The world is so small ;-)) Do your folks work for the Army? Unfortunatly I have no real contacts to army personel, as they also live quite separated from us Germans in their guarded living areas. (sad, but after 9/11, I really can understand all those security measures... I would do the same).

Please say "hello" to your relatives from a German guy that lives "next door" and still very much likes to come to North America (unlike some other Germans). So far I have only seen L.A. (my brother lives there) and NY, never been to Canada. But one day... ;-))

Have a good day in Canada!!!

Best regards
Jan

No-no, they are all Germans too, my wife's cousins. Lucas and Gabrielle have a law office in Bad Nauheim while Helen and Rudi live in Friedberg. Saw the Americans behind their security fences when we were over there visiting last year but didn't have any contact with them.

If you're interested in seeing some still shots of your area from our visit last year you (and anyone else reading this) would be welcome to view my gallery at photos.yahoo.com/sjhouse , nothing fancy, just some raw snaps.

Jan Zirn · September 21st, 2005, 11:43 PM

Thanks to all for your information

@ Chris: Thanks for your article. Very good explanation

@ Steve House: Very nice pictures!!! Thanks!!! Let me know when you're in Bad Nauheim next time. We can have a beer together and chat about video technology on your and my side of the ocean ;-)) My email is 'jan2_@_superjan.de' (please use without the _ in front and after the @. I added them to prevent spam robots to be able to make use of this post).

Let's all hope that the first XL H1 production model tests will be out soon in November ;-))

Best regards to all

Jan

September 21st, 2005, 02:00 AM	#1
Jan Zirn New Boot Join Date: Mar 2003 Location: Bad Nauheim, Germany Posts: 7	1440x1080 is 16:9? Hi All, I think I missed something on this obviously great cam: In the specs it says that the XL H1 records in 16:9 HD with 1080 lines. For me this means, it needs 1920 columns to achieve this. But Canon USA says on their web page that it only has 1440, which is rather a 4:3-format. How do they get to 1920? Ist this this horizontal pixelshift thing? So they basically "calculate" a full 1080x1920 picture from two 1440x1920 pics? Or how does it work? Sorry, if this question sounds stupid, but I did not find an answer anywhere... Thx Jan (from Germany)

September 21st, 2005, 04:54 AM	#2
Martin Mayer Major Player Join Date: Jun 2004 Location: Oxfordshire, UK Posts: 416	The pixels aren't displayed as square? (Like all SD video pixel formats as well: none of them is square. They're rectangles!) __________________ Martin at HeadSpin HD on Blu-ray

September 21st, 2005, 05:18 AM	#4
Martin Mayer Major Player Join Date: Jun 2004 Location: Oxfordshire, UK Posts: 416	Well, you will get a full screen display, if the display driver is correctly transforming the HDV into the correct aspect ratio: it will broaden the pixels to cover the full 1920 pixels across the display. Display drivers already do this when displaying SD video on square pixel (e.g. computer LCD) displays. e.g. in SD, 4:3 PAL is 720x576 pixels, which need to be stretched out wider to fill 768x576 to reach the correct 4:3 ratio on a square pixel display. __________________ Martin at HeadSpin HD on Blu-ray

September 21st, 2005, 06:09 AM	#6
Pete Bauer Wrangler Join Date: May 2003 Location: Eagle River, AK Posts: 4,100	Perhaps it is just a slight bit premature to feel sad? None of us has used the camera yet or seen the picture it will be able to produce. Full native 1920x1080 is still very high-dollar stuff. My understanding is that even many of the professional HD cameras have used either the same 1440x1080, or 1280x1080 (DVCProHD), and stretched the pixels to get 1920x1080. So based on the raw pixel count by itself, I don't think there is cause for disappointment quite yet. For more info, see this post by Thomas Smet: http://www.dvinfo.net/conf/showpost....2&postcount=18 in this thread: http://www.dvinfo.net/conf/showthread.php?t=51177 Personally, I feel more like a kid in a candy store to see cameras costing under $10k US go from 720x480 with 4:1:1 to either 1440x1080 with 4:2:0 (H1 HDV), 1440x1080 with 4:2:2 uncompressed (H1), or 1280x1080 (HVX200) with 4:2:2. These new cameras will have at least FOUR times the resolution of DV. And raw pixel counts aren't the whole story. Among many factors, the lens, the signal processing, and the recording format all play large roles in what the eye finally sees. I'm excited about the choices we will soon have! __________________ Pete Bauer The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. Albert Einstein Trying to solve a DV mystery? You may find the answer behind the SEARCH function ... or be able to join a discussion already in progress!

September 21st, 2005, 08:46 AM	#10
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	Pixel aspect ratio, and how 1440 becomes 1920, explained here: http://www.dvinfo.net/canonxlh1/articles/article06.php __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

September 21st, 2005, 05:08 AM	#3
Jan Zirn New Boot Join Date: Mar 2003 Location: Bad Nauheim, Germany Posts: 7	Hi Martin, thx for the answer. This means, with the XL H1 we won't get the full 1080x1920, even if we have a 1080x1920 display (I haven't seen those yet for retail customers, but they will be coming...). mmmhhh only an interpolated picture. This is kind of sad, isn't it? Thanks anyway Jan

September 21st, 2005, 05:48 AM	#5
Jan Zirn New Boot Join Date: Mar 2003 Location: Bad Nauheim, Germany Posts: 7	Hi Martin, sure the display won't show black pixels it's borders. What I ment was, that there would be some kind of interpolation within the camera as it's 1440 horizontal pixels must somehow fit into the 1920 pixels of the display (by means of interpolation). So some "neighbor pixles" will always be the same = loss of detail compared to a real 1080x1920 picture. This is, what I think is sad for such a highend piece of technology...

September 21st, 2005, 06:22 AM	#7
Jan Zirn New Boot Join Date: Mar 2003 Location: Bad Nauheim, Germany Posts: 7	I fully agree on the "kid in the candy store" ;-)) and I hope you did not get me wrong. I own a XL1s for 3 years now and I still think it's a good piece. Of course the XL H1 will be a biiiiiiiiiiig step forward compared to the XL1s (not to mention the XL2, which I never tried so far, to be honest). But, as I learned now, it's not a true 1080x1920 cam (which I thought it was). OK, this does NOT mean, it's not worth the money. In fact: I cannot make a judgment on this as I havn't seen it so far (of course;-)). And you are absolutly right there are many other features that determine the final quality of the output. I only worry a bit about someting completely different: That is that users will get problems with picture sharpness. Especially when filming moving stuff, free hand with auto-focus (I know, most people here prefer not to use the autofocus...). Canons always used to be a little on the "soft side" in AF mode, which may be only noticeable for the expert on standard definition (my parents never saw it ;-))). But on HD?? mmhhh... I hope it's different this time. Regrads Jan

September 21st, 2005, 06:28 AM	#8
Steve House Inner Circle Join Date: Mar 2005 Location: Hamilton, Ontario, Canada Posts: 5,742	There's image aspect ratio, pixel aspect ratio, and image pixel count or resolution. The pixel count in the high def HDV image is 1440x1080. The pixels themselves are rectangular, wider than they are high, in the proportion of 1.333:1. Multiplying 1440*1.333 gives you 1920 for a 16:9 aspect ratio HDV screen size of 1920:1080. I see you're in Bad Nauheim - I have family both there and next door in Friedberg!

September 21st, 2005, 07:25 AM	#9
Jan Zirn New Boot Join Date: Mar 2003 Location: Bad Nauheim, Germany Posts: 7	Hi Steve, thanks for your help. Yeahh, famous Bad Nauheim, where Elvis the King used to live when he was in the Army ;-)) (and did his service in Friedberg, which is only 2 mls away from Bad Nauheim). The world is so small ;-)) Do your folks work for the Army? Unfortunatly I have no real contacts to army personel, as they also live quite separated from us Germans in their guarded living areas. (sad, but after 9/11, I really can understand all those security measures... I would do the same). Please say "hello" to your relatives from a German guy that lives "next door" and still very much likes to come to North America (unlike some other Germans). So far I have only seen L.A. (my brother lives there) and NY, never been to Canada. But one day... ;-)) Have a good day in Canada!!! Best regards Jan

September 21st, 2005, 11:43 PM	#12
Jan Zirn New Boot Join Date: Mar 2003 Location: Bad Nauheim, Germany Posts: 7	Thanks to all for your information @ Chris: Thanks for your article. Very good explanation @ Steve House: Very nice pictures!!! Thanks!!! Let me know when you're in Bad Nauheim next time. We can have a beer together and chat about video technology on your and my side of the ocean ;-)) My email is 'jan2_@_superjan.de' (please use without the _ in front and after the @. I added them to prevent spam robots to be able to make use of this post). Let's all hope that the first XL H1 production model tests will be out soon in November ;-)) Best regards to all Jan