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-   Canon XL and GL Series DV Camcorders (https://www.dvinfo.net/forum/canon-xl-gl-series-dv-camcorders/)
-   -   Still confused over 16:9 vs 4:3 (https://www.dvinfo.net/forum/canon-xl-gl-series-dv-camcorders/83910-still-confused-over-16-9-vs-4-3-a.html)

Gary Gonsalves January 15th, 2007 01:26 PM

Mark, the project is not ready for broadcast. I am just trying to head off a disaster and a waist of time. I love the look of widescreen but if it is bound to only dvd, then I will change direction.

Here is a tutorial regarding widescreen. It is located on the digital juice website. I did notice that he mentioned that the yes, anamorphic is squeezing the widescreen video to 4:3, then the DVD player will recognize it and convert it back to display widescreen.

But....... once again, this is for DVD. Broadcast is not mentioned.

Here is the link http://www.digitaljuice.com/djtv/seg...how=all_videos

Boyd Ostroff January 15th, 2007 01:35 PM

Here's a little background on the anamorphic process - from one of my favorite websites, The American Widescreen Museum: http://www.widescreenmuseum.com/widescreen/squeeze.htm

It was originally an optical process which allowed existing film cameras to shoot widescreen movies with the help of a special lens. Later the same technique was used with video cameras. But today, cameras with high enough resolution CCD's can capture the full image natively, then use a digital process to provide the squeezing. This is what the XL2 does.

Mike Teutsch January 15th, 2007 01:59 PM

Quote:

Originally Posted by Boyd Ostroff
I think we're just into semantics here, but the XL2 has to "anamorphise". The only way to shoot 16:9 on DV is to make the image anamorphic - to squeeze it to fit the 4:3 standard DV frame size.

When I shoot 16:9 I don't squeeze anything to 4:3, nothing. The XL2 shoots true 16:9 right? You are not cropping a 4:3 image? Right. If it reduces the size slightly, to me that is not anamorphizing! Just me maybe!!!!

My thesaurus says: Anamorphic===Pertaining to a kind of distorting optical system! Optical-----"Read Lens!"

Are you saying that there is no different term to be used with the XL2 or other camera's process, if so maybe we need to start one before people start to look to buy an anamorphic lens for their XL2's and other cameras.

From Canon's and every reseller’s description------"Canon XL 2 shoots in a true 16:9 ratio without artificial letter-boxing or vertically squeezing a 4:3 image."

So maybe we need a new term!!!!!!!!!!!!!!! I'm all for it.

I have nothing against me being wrong, "dead" or otherwise, but just want to clarify our terminology. Just think that that term does not belong in this discussion.

Mike

Edit.

Check your ------http://www.widescreenmuseum.com/widescreen/squeeze.htm, and almost every paragraph mentions "Lens." So let's coin a new term for it!

Mike

Boyd Ostroff January 15th, 2007 02:30 PM

Quote:

Originally Posted by Mike Teutsch
When I shoot 16:9 I don't squeeze anything to 4:3, nothing.

Your camera is doing the squeezing, you just don't realize it :-) And things change fast in the digital world, so a thesaurus isn't always right. Just plug your camera into a regular 4:3 monitor or TV. What do you see? Everything is squashed, so it's too tall and skinny. That's exactly what the XL2 has recorded on tape. You need a 16:9 capable monitor to unsqueeze it.

Read back through some of the posts above... Dave explains it very well. The number of pixels in 4:3 and 16:9 video are exactly the same, but the pixels themselves are differently sized. This has to do with the way the display device interprets the data. On a 16:9 screen the same 720 pixels fill a wider space.

This is the very definition of "anamorphic"... you have changed the shape of the original image. As I mentioned above, this was originally done optically on film cameras. Now we can do it digitally and get the same effect.

When we talk about "true 16:9" or "native 16:9" that just indicates the camera's CCD's have enough pixels to capture a full resolution widescreen image. So we're talking about the method of acquisition there. The anamorphic process is the method to storing the image in a format which is compliant with DV's 720x480 spec. In other words, it's a bit of a "kludge"... a way to fit a rectangular peg into a square hole if you will.

We don't need a new term. "Anamorphic" just means you've changed the shape, it doesn't say HOW you changed the shape. You can do that with optics, analog circuits, or digital processing. That term is actually the very heart of this discussion, and it's the correct one to use.

Don't feel bad, it has caused a lot of confusion in the past and it took me awhile to wrap my brain around the concept also :-)

Boyd Ostroff January 15th, 2007 02:33 PM

Maybe this old thread will help?

http://www.dvinfo.net/conf/showthread.php?t=29087

Mike Teutsch January 15th, 2007 02:42 PM

Quote:

Originally Posted by Boyd Ostroff
I think we're just into semantics here, but the XL2 has to "anamorphise". The only way to shoot 16:9 on DV is to make the image anamorphic - to squeeze it to fit the 4:3 standard DV frame size.


Wrong! Neither me nor my camera squeezes anything to 4:3, it squeezes it to 16:9!

Greg Boston January 15th, 2007 03:05 PM

Quote:

Originally Posted by Mike Teutsch
When I shoot 16:9 I don't squeeze anything to 4:3, nothing. The XL2 shoots true 16:9 right?

As weird as it may seem, Mike, that's exactly what happens, as Boyd explained.

The 'shape' of the CCDs on the XL2 are natively wider than tall (960H X 480V). When you record in 16:9, the XL2 takes those 960 horizontal pixels and maps them onto a 720 pixel horizontal grid. It has to do that to conform to the DV spec of 720X480.

It flags the video as 'anamorphic' as it goes to tape. When you get ready to import to the NLE, it typically doesn't know about the flag so you have to inform the NLE that your video is 'anamorphic'. This tells the NLE to display your video with the 720 pixels elongated to make the picture wide (16:9) as you work with it. However, there is still only 720 horizontal pixels in your video.

Now, let's say you get ready to author to a DVD. Once again, you have to tell the DVD software to place an 'anamorphic' flag bit on the DVD as it's burned so the player will know what to do with the video when playing back. Graphics files such as menus or animations, don't have any of this anamorphic stuff cause they aren't limited by any spec as to number of pixels. So if you create widescreen graphics or animation, you use 853X480, or more simply 16:9 reduces to 1.78:1. Take 480 and multiply by 1.78 to arrive at the correct number of horizontal pixels.

NOW HERE"S THE RUB. Most folks don't know enough to go into their player's video setup menu to instruct it as to what kind of tv they have attached, 4:3 or 16:9. And for some reason, many players default to 16:9.

So if you have a 4:3 set, and your player sees a DVD with the anamorphic bit set, it will react correctly by placing black bars top and bottom if the player knows you have a 4:3 screen. If it thinks you have a 16:9 screen, it will do nothing, and on a 4:3 screen this would show as a squished image (faces are very thin), but on an actual 16:9 tv it will appear correctly.

Long winded I know, but sometimes explanations from a different angle make things clear. Hopefully I was able to help. If not, reading a couple different explanations might work.

regards,

-gb-

Chris Hurd January 15th, 2007 03:18 PM

Excellent reply there, Greg... spells it out beautifully.

Some folks seem to be confused about the XL2... yes it is native 16:9 on the CCD block, but it *must* go to tape as 720 x 480, because if it didn't, well then it wouldn't be DV. That's where some people are getting hung up. Some monitors will show it as a Spaghetti Western (that is, squished), if the monitor can't add its own letterbox.

Mike Teutsch January 15th, 2007 03:22 PM

See, now we are having fun, and everyone is learning. But, if it squeezes it to 4:3, why does my 16:9 TV show it as 16:9? I thought it was 4:3? It should have black bars on the sides!

Mike

Chris Hurd January 15th, 2007 03:32 PM

Nope. It would have black bars on the sides only if it was shot in 4:3.

Your widescreen monitor is smart enough to recognize the 16:9 flag, and un-squeezes it for proper display.

But older 4:3 monitors don't know what to do with it and therefore show it squished (Spaghetti Western).

Boyd Ostroff January 15th, 2007 03:36 PM

Quote:

Originally Posted by Mike Teutsch
But, if it squeezes it to 4:3, why does my 16:9 TV show it as 16:9? I thought it was 4:3?

Mike, as we've all been saying, the DV spec only supports 720x480 pixels. This was originally intended to be interpreted by a TV in the 4:3 aspect ratio. So if you're going to record something in the DV format, it has to be 720x480.

Now when you view that 720x480 image, it's up to your TV to fit it onto the screen in the correct proportion. Your 16:9 TV will have several different display modes which you can choose with the remote. On my Panasonic plasma they're called FULL, ZOOM, JUST and 4:3. The default is for the screen to choose FULL mode, where it fills the entire screen with whatever you're sending it. Now this TV (as well as the 3 other 16:9 LCD's that I have) doesn't seem to care whether you're feeding it 16:9 or 4:3 material. It's up to you to choose the mode you want to view it.

So if you're watching widescreen material from your XL2, it will be in the correct proportion if the screen is set to FULL. But now playback a 4:3 tape... it will still fill the screen but everything will be stretched too wide. In that case, it's up to you to choose 4:3 mode to squash it back into the correct shape and add the black bars on either side (known as "pillarboxing").

Gary Gonsalves January 15th, 2007 03:39 PM

Michael,

I couldn't have said it better. This is why these boards are great, we can take the opinions of several and come up with some common factors. I have learned a lot from this post. (Disclaimer: Not to say this will be my last post)

Thank you everyone! I am going to have to leave now since my wife is calling for me to watch some Ben Afflack movie (getting sick!). Let's see if it is in widescreen!

Thanks again guys!!!

Boyd Ostroff January 15th, 2007 03:39 PM

Quote:

Originally Posted by Chris Hurd
Your widescreen monitor is smart enough to recognize the 16:9 flag, and un-squeezes it for proper display.

Heh, yours is smarter than mine then :-) None of my 16:9 screens seem to recognize this (Panasonic plasma, Samsung LCD, Sony LCD and Gateway LCD). You have to choose the desired mode yourself.

Now this only applies to standard definition video though. High definition would always be correctly displayed as 16:9

Mike Teutsch January 15th, 2007 03:43 PM

Quote:

Originally Posted by Chris Hurd
Nope. It would have black bars on the sides only if it was shot in 4:3.

Your widescreen monitor is smart enough to recognize the 16:9 flag, and un-squeezes it for proper display.

But older 4:3 monitors don't know what to do with it and therefore show it squished (Spaghetti Western).

Exactly, and this goes back to the original question that Gary Gonsalves was asking!!!!

He was asking about those with only 4:3 sets! And, I said that it would be squished down and stretched out with black bars on the top and bottom. Right or wrong? I originally answered this based on his question, with no concern for anamorphic lenses or anything, just how others would view his footage.

I know I am less than brilliant in this area, but does this not mean that my original answer was correct?

Thanks all----Mike

P.S. This is fun and I hope I'm not pissing anyone off, but we are learning a lot. Tell me to stop if you want!

Mike

John Miller January 15th, 2007 03:54 PM

Since we're in learning mode (!) - you may also be interested to know that the DV specification supports more than just 4:3 or 16:9...

DV playback equipment *should* send the appropriate display mode signals out on the analog video signal. There are two standards supported:

The IEC standard - three possibilities here:

4:3 full format
16:9 letterbox (centered)
16:9 full format (squeeze)

The ETS standard - eight possibilities here:

4:3 full format
14:9 letterbox (centered)
14:9 letterbox (top of screen)
16:9 letterbox (centered)
16:9 letterbox (top of screen)
>16:9 letterbox (centered)
14:9 full format
16:9 full format (anamorphic)

All, of course, constrained to 720x480 or 720x576.

Did you also know that the DV specification supports Closed Captions and Teletext? My DSR-11 even encodes analog CC signals into the DV stream.

And, since a picture paints a thousand words, here is a true 16:9 DV image represented as a square-pixel 720 x 480 JPG:

http://www.enosoft.net/DVProcessor/native16_9_2.JPG

and its letterboxed (but still 720 x 480) equivalent:

http://www.enosoft.net/DVProcessor/letterboxed_2.JPG

(they are deliberately chosen to show the interlacing).


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