View Full Version : Red stripes in Frame Mode !?!


Hitcher.
April 11th, 2002, 09:23 PM
Hello,
I just watched some captures made from Frame Mode footage and I like the picture I get with my PAL XL1S in this mode, except...
Everytime when there is some bright red or orange, it's turn to make some curious red stripes in the middle of the colored parts.

There is 2 small pictures for exemple here:

http://www.cinedvd.net/framestripes.jpg
http://www.cinedvd.net/framestripes2.jpg
(resolution is X2)

Do you get this on your computer monitor? (this is not, of course, interlaced alliasing)

If yes, how to avoid this, except not filming bright red colors :-)
Thanks for your replies

Rob Lohman
April 12th, 2002, 01:25 AM
I have the same model as the XL1s as you do. I also noticed
some weird things with the red colors, but not as much as your
second photo though. I am beginning to wonder (myself) if
this is do to the DV codec I am using, because I do not tend
to see it on my TV when played back directly from the camera.

What OS / DV codec/card are you using?

Hitcher.
April 12th, 2002, 03:20 AM
<<<-- Originally posted by Rob Lohman : I am beginning to wonder (myself) if
this is do to the DV codec I am using, because I do not tend
to see it on my TV when played back directly from the camera.

What OS / DV codec/card are you using? -->>>


I made my captures on XP via standard firewire card and Vegas Video.
But I tried with Premiere and there is the same trouble.
I think it's maybe from the pixel shift technology...

Rob Lohman
April 12th, 2002, 09:41 AM
CApturing does not deteremine your quality!! Why? Because
you are only **transferring** a data stream. You are not
really "Capturing" like you did in the old days (ie, convert
from analog to a digital source -> thus using a codec).

On what machine did you play (took the screen captures)?
Thats when the DV Codec is being used, not earlier.

Hitcher.
April 13th, 2002, 12:15 AM
I also notice theses defects on my TV when playing the DVtape via the camera.
TV low definition nearly make them disapear but there're still visible when watching carefully.

Nobody have an idea to avoid theses red stripes in frame mode?

Jeff Donald
April 13th, 2002, 03:28 AM
Hi,

The frame mode uses interpolation. The algoritham may have a problem with some colors, lighting, motion etc. I would talk to Canon and see what they say.

Jeff Donald

Hitcher.
April 17th, 2002, 09:47 PM
Jeff?
Any news from Canon about this issue?

I really would like to know if this problem can be resolve or if it is a negative aspect of the technology used in the Frame mode.
Thanks

Jeff Donald
April 17th, 2002, 10:11 PM
Hi,

Sorry, but my post lost something in the translation. By I (meaning you), I meant that if it was my camera I (meaning you) would talk to Canon and voice my concerns. Customer service in France would have a much better idea about PAL (and any potential problems) than here in the States.

sorry again for the confussion.

Jeff Donald

Hitcher.
April 18th, 2002, 08:16 AM
Of course, I contacted Canon in France, and they're not aware of this problem.
I'm still waiting somebody call me back about this issue.

When you speak about NTSC VS PAL, do you mean you don't have the red stripes in frame mode when watching bright red footage on your computer, on your NTSC XL1?

Nori Wentworth
April 18th, 2002, 12:25 PM
Ahhh!!!
the evil mesh!

Jeff Donald
April 19th, 2002, 12:25 PM
I use the frame mode very little on the XL 1. In NTSC Frame Mode I get patterns (not all the time) and an increased edge detail (more often) but nothing like what you show. It is not associated with the color red either. I've always attributed to problems to the algorithym used for interpolating the Frame Mode.

Jeff