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-   -   16:9 and Frame Mode Together (https://www.dvinfo.net/forum/canon-gl-series-dv-camcorders/12000-16-9-frame-mode-together.html)

David Ziegelheim July 13th, 2003 05:02 PM

16:9 and Frame Mode Together
 
Both of these involve some image interpolation. Does anyone use them together? How is the image? Do you have samples with them together and them off on the Internet?

Thanks,

David

Mike Ostracky July 13th, 2003 05:48 PM

I use them...
 
I use frame mode and widescreen mode together, I`ve recently done some tests, and I must say it looks great (to my eye, but then again, I`m not a nitpick :)).

So, I find it great enough.

Here is a link that may help you in some way -

http://members.macconnect.com/users/.../resboost.html

It serves you with a much needed conclusion - you decide. I agree with him.

Enjoy.

Charles King July 13th, 2003 06:36 PM

Hey Mike, your pics doesn't seem to load or it's taken one helluva time loading. I'm still waiting but nothing appears.

Mike Ostracky July 14th, 2003 04:17 AM

Oh...
 
Have you copy-pasted the WHOLE link in the address bar ? I`ve tested it on two computers and the link works.

http://members.macconnect.com/users/b/ben/widescreen/resboost.html

Try again, and tell if you succeed.

Rob Lohman July 14th, 2003 04:27 AM

Works fine here!

Charles King July 14th, 2003 04:37 AM

I guess it's me then because the page comes up(pinkish color right) but then the expolorer icon continues to seach and search like it's trying to load but can't. Weird.

Imran Zaidi July 14th, 2003 08:03 AM

OK, somebody explain to me why everyone suggests using the camera's on board digital 16x9 is so horrible if it actually produces better resolution. Are there any other considerations?

One things for sure though... Frame mode on the GL cameras does produced reduced resolution. Looks good, I think, but it has lowered resolution, no question.

Rob Lohman July 14th, 2003 08:28 AM

Who says it increases resolution? What it does is use the available
DV bandwidth better. Since you are only encoding what you will
end up using those pixels have "less" compression. However
you will loose:

1) correct aspect ratio in the viewfinder

2) ability to do a 4:3 output of the movie

3) frame your movie in the editing room

So no, you don't increase resolution, you just utilize the band-
width better [this is all related to the Canon camera's!].

The stretch is still electronic and will be the same in camera or
done in post (with the advantage and disadvantages mentioned
above!).

David Ziegelheim July 14th, 2003 09:31 AM

The reason for my question is that both frame mode and 16x9 cause a drop in resolution.

Frame mode is known...it has 360 effective lines. That's a drop of 25%, although stills from individual frames increase 50% (from 240 lines) and you get a film like motion effect.

16x9 also causes a reduction. But since the camera can use the full width of the CCD and its extra 4% vertical resolution over the DV image, the exact loss is not known.

Individually, both are acceptable. But together, is the loss unacceptable. Mike's example shows that using the camera's 16x9 is better than doing it in post. Your 4:3 version would then have to be a crop and zoom with yet lower resolution.

You can always use a DVX100 to get true, full resolution progressive mode and crop and zoom in post.

So has anyone run both at the same time?

Mike Ostracky July 14th, 2003 01:46 PM

I run the together...
 
In a month or two I`ll buy myself Canons Wide Angle lens, but untill then I`ll use camera`s 16:9 mode. You might ask why, I`ll tell you - because my eyes detect no loss in resolution, it is all subjective but frame mode looks sharper to me than deinterlacing.

So, from my experience, I would say thath using 16:9 and Frame Mode together is the winning combination. Go for it. If you want something that really is better than in-camera 16:9 go for wide angle lens, it is worth it - until then, you`ll (probably be, like me) pleased with the included solution.

Enjoy.

Charles King July 14th, 2003 02:12 PM

Mike.

Could you please send me a copy of the clip through my e-mail as I still cannot view your page. If it's not too much trouble. Thanks

Mike Ostracky July 14th, 2003 04:15 PM

Here...
 
It`s not a problem, I`ll post it here for you and if anyone else has problem with the site - so it`ll be available here.

***

So, your camcorder has a fake electronic 16x9 option, which reduces your resolution. But you can't afford an anamorphic adapter from Optex or Century Precision Optics any time soon, and you like the widescreen look. Someone might have even advised you to shoot normally and letterbox it later instead of shooting in the digital 16x9 mode. Well, oddly enough, shooting with the digital 16x9 may give you slightly better resolution than shooting normally.(Of course, shooting with an anamorphic adapter is still far better than in-camera 16x9.)

The "16x9 mode" footage is signficantly sharper vertically. Since the image is compressed after it's been enlarged on the vertical axis, it's maintaining detail on the CCD that normally would be "fudged" by the DV compression.


Methodology:
These are details from a standard resolution chart (EIA Chart 1956), shot with a Canon GL1. They were taken from identical viewpoints, with identical settings. (I can't recall the exact numbers, but they were both shot with manual exposure, manual focus, and in progressive Frame mode.) The only difference between the two samples is that in the one on the right, the electronic 16:9 was activated. They were both transfered via Firewire to my Mac G3. In Adobe After Effects, in their native DV format, they were both de-anamorphized (from 1.125:1 for the normal DV to account for pixel aspect ratio, and from DV-ratio 16:9 for the electronic widescreen DV), while being magnified to show detail. Both of these image transformations happened at the same time, by one high-quality (spline-based) scale transformation. What does this mean? It means that these images have only been touched by the software once, and that you're seeing nearly 100% of the detail in the original image, with as few as possible artifacts. The resulting images were saved as uncompressed PICTs (lossless), cropped, and finally exported as high-quality JPEG files for viewing on the web. What you see on your screen is both an extraordinarily good representation of the detail in the images, and a nice demonstration of a phenomenon which I've observed first-hand a number of times.


FAQ:


Q: Did you screw up?
No, I ran this test several times. This set of samples is indistinguishable from the others. However, while my methodology is solid and backed up by a strong technical theory, this was not a scientific (or heavily researched) test, so I would be reluctant to draw empirical data from the results. In short, no, I did not screw up.


Q: You just blew my mind. Why is there a difference?
It's really not that surprising; when in 16:9 mode, the 16:9 area (~720x360 pixels) of the image is enlarged digitally to 720x480 before being compressed, therefore allowing all of the Discrete Cosine Transform (DCT) compression blocks to be utilized in compressing the image. When the digital 16:9 is turned off, the 16:9 area only occupies 75% of the total image, which means there aren't as many DCT blocks working on that area, thereby lowering the image quality.

***

There are two enlarged pictures with the article - one is without 16:9 mode, it is, blurry, and other is with 16:9 mode, that one is really quite sharper. If you still want mail with whole article I will e-mail it to you as soon as I`ll can.

David Ziegelheim July 14th, 2003 10:13 PM

Now we know the 16:9 electronic anamorphic feature is better than cropping a 4:3 image.

But is it still ok in frame mode with another 25% image resolution loss? Not necessarily compared to making the same resolution it self but compared to an interlaced 4:3?

Mike Ostracky July 15th, 2003 03:44 AM

Here`s what I would do...
 
Film exactly the same thing (under decent lighting conditions) with manual controls with frame mode on, and off - upload them onto computer - see what you like, now deinterlace the interlaced image and see do you like more frame mode image or deintarlaced.

Like I said, I find frame mode sharper and overall more pleasing.

Hope this helps.

David Ziegelheim July 15th, 2003 07:32 AM

Mike,

I'm sure frame mode by itself looks good, and frame mode stills look better than interlaced stills.

And 16:9 mode looks better than 4:3 mode cropped and zoomed.

But what about both together?

The Canon is the only one that has both together. The Panasonic has true progressive but no 16:9 mode. The JVC has neither progressive, frame, nor 16:9 mode (both support letterbox). And the PDX10 supports a superior 16:9 mode but no progressive or frame mode.

The GL2 comes to the table with great promise. Does it also have great reality?

David


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