7D RAW video has a white artifact in center. Not in stills.

Started by reziarfg, January 22, 2015, 04:22:13 AM

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reziarfg

I hope this is the right place for this. I searched the forum but couldn't find this exact issue.
I am seeing a strange artifact near the center of the frame which manifests as a bright white area of about 2 pixels. I don't see this in RAW stills or Canon video. Only RAW video.
Here is a video of what I'm talking about:

Happens in crop or regular recording mode.

Please disregard the noise as it's pretty dark in my room and I expect that. I'm talking about the specific and very obvious white artifact in the center area.
Below is the information for my setup:

Camera: 7D running 2.0.3
ML version: Nightly.2015Jan15.7D203 (although it's happened with previous versions)
Card: Lexar x1066 benched at around 90MB/s
Video resoluation doesn't seem to matter, but example is at 1280x720 I believe
Appears regardless of whether I use MLV Converter 1.9.2 or raw2cdng 1.6.5 to process the MLV file

If this is a case of dead/stuck pixel(s) it's the most obvious I've ever seen. Additionally, I took a look at the sensor and don't see anything obvious like dust/scratches.

Thanks for reading. It's my first post, really hope I'm doing it right. :)

DeafEyeJedi

Well you can try another CF card to verify whether it's a bad card or the sensor itself?

Could that be a dead pixel coming from the CF card itself...
5D3.113 | 5D3.123 | EOSM.203 | 7D.203 | 70D.112 | 100D.101 | EOSM2.* | 50D.109

reziarfg

I've never known dead pixels to come up white. Aren't they usually RGB or black? It looks like it's doing the same thing with other cards as well.
I tried again without crop mode and it's less apparent, probably because it's not at a 1:1 pixel ratio(I think that's how it works, right?)

Regardless, it's really distracting and makes the footage useless. I've looked through the forums on stuck pixel removal and it doesn't seem like there's an easy way to handle it. But that's mostly because the pixels jump around. I wonder if there's a way to remove it when it's always in the same spot. Seems like it might be easier.

DeafEyeJedi

Weird. Does it still show even after uninstalling ML?
5D3.113 | 5D3.123 | EOSM.203 | 7D.203 | 70D.112 | 100D.101 | EOSM2.* | 50D.109

reziarfg

When taking a normal video using a card without ML I don't see it at all. Then again, the video is pretty mushy comparatively and who knows what Canon's software is doing to it as it's encoded. So I'm not terribly surprised.

The fact that I don't see it in RAW stills might just be a result of ACR removing something. I bet I could find something if I could see the raw bayer array data. I'm guessing it is in fact something on the sensor.

DeafEyeJedi

Interesting... Perhaps you can give me the settings you have enabled in ML and I'll see if I can duplicate your issue regarding the white pixel on my 7D.

Like which modules are enabled... Which FPS... Which lens did you use? Does it show white pixel regardless of lens or the settings (both Canon and ML)?
5D3.113 | 5D3.123 | EOSM.203 | 7D.203 | 70D.112 | 100D.101 | EOSM2.* | 50D.109

reziarfg

Thanks for all your help/suggestions.
I was originally using a Canon 10-22 lens zoomed all the way out to play around with my widest FOV in crop mode. It was most apparent here.
When I'm not using crop mode it's less apparent. Unfortunately, I'm at work now so I can't give you too many settings details except I was in 1280x720 resolution in crop mode.

It does look like I can actually see it in the preview as well. Below is another Youtube video demonstrating this. It looks like it's red or sometimes blue looking in the preview but always white in the final output. So maybe it is a stuck pixel after all and somewhere in the process it's being made white. I wonder if it's the chroma smoothing from MLV converter. When I get home I'll try again without that setting and see if it's still white or if it's a colorful dot.


DeafEyeJedi

5D3.113 | 5D3.123 | EOSM.203 | 7D.203 | 70D.112 | 100D.101 | EOSM2.* | 50D.109

reziarfg

I'm using MLV Converter 1.9.2 although I did try with latest version of raw2cdng (1.6.5?) and see the same issue. :(

I did try to convert it without Chroma smoothing and will say that it looks much more like some sort of pixel. Still not sure why it's white though. I've never seen a stuck white pixel.
Below is a youtube video of what it looks like converted without chroma smoothing(recommend viewing in HD):



EDIT: I don't know why, but Youtube's conversion made the video kind of mucky. Anyway, you can still see the white dot. It's there 100% of the time.


reziarfg

I did try MLRawViewer. It plays the video and shows the same very hot pixel in the center area. It's just so blatantly there! Agh!
I took a look in http://rawtherapee.com/ at the stills and zoomed in in non-demosaic view. It looks like I've got two stuck green pixels and maybe one stuck red pixel all clustered together. I'm not sure there's a resolution. None of the stuck/dead pixel fixers I've tried can fix it. It's just too big. Doesn't show up in non-ML stills and video though so I guess Canon's baked-in pixel remapping has a bit more gumption.

Thanks for the suggestion though.

Frank7D


DeafEyeJedi

5D3.113 | 5D3.123 | EOSM.203 | 7D.203 | 70D.112 | 100D.101 | EOSM2.* | 50D.109

reziarfg

Hmmm. I think I know what you're talking about. It actually automatically processes in ACR giving me options for WB, etc. But it doesn't remove that dot. I think it's the perfect storm of exactly the dead pixels that ACR can't remove. I tried Photoshop as well and it appears there when opening the DNGs.

My guess is it doesn't appear in my Non-ML stills because of Canon's own pixel remapping which doesn't happen when doing raw capture.
It is there in live-view silent capture ML as well. Probably because it's a raw read of the sensor too?

reziarfg

FYI guys and to anyone else who might be experiencing a particularly stubborn dead pixel. I found a somewhat acceptable solution. It's not perfect, but you can use AE's CC Simple Wire Removal tool to "mask" out the dot.
I'll have to do some more testing, but it seems at least somewhat effective.
Here's a video demonstrating the fix:




And here is the result of my attempt on the same dark grainy video. Probably a poor example but I'll play with it a bit more in the future.


I don't know why my youtube videos upload terribly when I'm saving in H.264 in HD at a high bitrate...Should still give you an idea.

smok29

Guys, I have a problem with ML on 7D.
RAW recording works perfectly but when i want to record in MLV i doesn't start.
ML version: magiclantern-Nightly.2015Jan29.7D203

walter_schulz

Use RAW recording *or* RAW (MLV) recording, not both at the same time.


walter_schulz


smok29


walter_schulz

Delete ML directory and Autoexec.bin. Copy extracted nightly contents to card. Insert card into cam and start again.


walter_schulz

Strange.
Enable Frame Skipping in RAW (MLV) submenu. Just for debugging this one.

smok29

Still nothing. I've tried to install ML on another CF card and the same

Levas

@reziarfg

About that stuck hot pixel in your 7d. Have you tried the Canon way of remapping hot/dead pixels.
Google for "canon hot pixel remapping"

Take the lens of, put body cap on the camera and activate manual sensor cleaning in the canon camera menu.
And wait for several minutes.

Sometimes it helps to "warm" up the sensor by using live view on a high iso, before you do the manual sensor cleaning.


walter_schulz

@smok29:
Running out of options here.
1) Re-download nightyl build and copy extracted contents to card. Overwrite existing files.
2) You may try to reset cam to factory defaults (including C.Fn).

smok29

Thank you walter for your help but it still doesn't work.

Walter Schulz

Zip ML\Settings directory, upload it and link it here.

smok29


Walter Schulz

Thank you. I'm able to reproduce this error with your settings directory.
Now trying to find out what's happening here.

EDIT: Created bug report.
https://bitbucket.org/hudson/magic-lantern/issue/2202/create-directory-on-recording-doesnt-start
Option "Create directory" doesn't work with 7D and never did.

@smok29: Next time it would be fine to tell that you have altered settings (and which one) after downloading/resetting ML.

smok29


reziarfg

So I did try the Canon pixel remapping around the same time I was troubleshooting this issue. It came up when I was looking online for solutions. It had no effect on raw video. My guess is that ML's raw video doesn't get processed by Canon in any way. Since it's "raw" the mapping doesn't take effect.
This would also explain why it doesn't show up in Canon video and stills.

Thanks for the suggestion though.