What causes pink frames in raw footage on a T3i?

[sloore]

I know that I already posted a thread earlier about fixing pink frames in post, but due to a lack of answers to that and the realization that trying to fix pink frames in post is not a practical solution for anything but a few minutes of footage, I am trying to find a way to fix the problem from the camera end.  So I put it to the folks here.

When I originally started shooting raw footage with magic lantern(same versions of ML and Tragic Lantern as there is now), I had little to no problem with pink frames, I would get the odd one here and there, usually at the beginning of a vlip, but that was it.  Now, I'm just getting them all the time, some shots have sections of footage where at least one in ten frames is pink.  I am not sure what changed to cause it.  The first time I noticed it was after the camera had sat in the trunk during a long car trip, so I wondered if it had to do with the camera being too hot, but even after the camera has sat in a cool spot for an extended period, the problem persists.  I have played around with all sorts of settings, but have not seen any correlating improvement to any change in settings.  I've gone down from 960x540 to a smaller 960x480, I've turned on DIGIC Poke(dunno what that does) since there was a thread on this forum where someone said "DIGIC V is immune to pink frames," I've reformatted to exFAT, , I've wiped my card and went with a clean install of ML and TL, I've played around with the liveview and global draw settings, I don't use sound recording, and have yet to find a setting that fixes the problem.  Though there are a lot of settings I can change and right now I'm just randomly changing things around without the slightest idea as to what is causing the problem.

So far the only thing that I've found is that I get better results with a a different card.  My faster card is a Sandisk extreme 95mb/s 32GB, and my slower card is a transcend class 10 32GB which I think can only write at about 20mb/s tops.  Ironically enough, the slower card gives me better results, but I have drop the resolution all the way down to 832x416 and besides, that doesn't make sense anyway.  Is it possible that an SD card can go bad?  Mind you, I've only had the sandisk card for a couple weeks.


Can someone tell me at least what general area I should be looking toward or if it is known what settings cause pink frames or at least increase/decrease the chances of getting them?

From what I've found in my searching the current versions of both ML and TL don't have much of a problem with pink frames, so I'm guessing that it's not a problem with the firmware itself.

Any help would be greatly appreciated.  Thanks

[sloore]

oooookkkkkaaaayyyyy



So, after doing some further looking, I have managed to narrow it down to an issue with the SD card.  I took the one that was giving me the problems, reformatted it again, but unlike every previous format, I did it through my computer and unchecked the "quick format" button.  It took a good long bit(about ten or fifteen minutes compared to the several second format time that the camera does), then copied the contents of the good card onto it.  After shooting about twenty minutes worth of footage, it looks like I've more or less fixed the problem, and though it does appear that the first shot after turning the camera on does seem to have a higher chance of getting pink frames; and multiple ones at that, every subsequent shot seems to be fine.  The only other issue seems to be that I get the occasional pink frame within the first second of "non-first" shots, but that's fine as I will almost never need anything from that early on in a shot.


From what I can gather, it seems that the pink frames seem to be a symptom of a lack of writing speed, and that once the camera or SD card have "warmed up" from the first shot, the problem largely goes away, and similarly it appears that the camera needs about a second to ramp up its write speed after it starts recording.  The UI says as much when I shoot with it starting out by telling me to expect to only get a couple thousand frames, and then that figure gets bigger and bigger until it eventually says that continuous shooting is OK.

I'm still curious as to what exactly caused the pink frames in the first place.  Was it a setting I had set which was saved on the offending SD card or was it a consequence of not doing a detailed enough format of it?  I've read that you should reformat your SD cards pretty often if you write to it a lot, and shooting raw video obviously does that.  I'm going to do some more experiments and reformat the card while installing fresh copies of ML and TL on the card in stead of copying them over from what was written on the good card.

[robbierob2005]

I have this same issue on my 550d (T2i) as seen in this post http://www.magiclantern.fm/forum/index.php?topic=7316.0

I'll give it a try and format my Sandisk Extreme Pro 32GB (95MB/s).  When I was receording in 1152x482 resolution I got about 3 half pink frames in +-240 frames of footage.

Also I read that turning off Global Draw will increase performance lightly? Haven't tried that one yet.

[sloore]

Make sure you do it on your computer and (in windows 7 anyway) uncheck the "quick format" option.  From my experiments so far, I've seen that even exFAT works, so if you're going to go through the trouble of doing a slow format, you might as well get the higher file sizes allowed by exFAT.  Now, I've only used exFAT after I had already installed ML on my camera, so I dunno if you can run "update firmware" on your camera with an exFAT formatted card, so be wary of that.  I'll be doing some further experiments this week to see what I can get away with.

[CFP]

If your buffer fills up you'll get pink frames. To avoid it, set the resoltuion in the Canon menu to 640p @ 30 fps (Lower YUV buffer = more space for other stuff) and use 'FPS Override' to lower the framerate. Also, make sure you have a fast SD-Card that reaches the 600D's 21 Megabyte/s write speed limit and set the 'Pic Quality' to 'SRAW' (And reboot your camera!) to increase the shoot_malloc buffer size. That should help to get rid of any pink frames. If they still appear you can try to use an older build.

By following these steps I haven't got any pink frames since weeks.

[spider]

...and set the 'Pic Quality' to 'SRAW' (And reboot your camera!) to increase the shoot_malloc buffer size.

But this only works with tragic lantern, which I never would use.

[deletedAcc.0021]

But this only works with tragic lantern, which I never would use.

This I have to hear .... and why would you "never" use Tragic Lantern?  What is your reasoning?

[iaremrsir]

But this only works with tragic lantern, which I never would use.

Is there even another build for the T3i that enables raw?

[spider]

This I have to hear .... and why would you "never" use Tragic Lantern?  What is your reasoning?

#10
http://www.magiclantern.fm/forum/index.php?topic=7058.msg59045#msg59045

[robbierob2005]

I used the raw_rec module from this post.
http://www.magiclantern.fm/forum/index.php?topic=5582.msg57683#msg57683

 I formatted my sd-card in my camera (low-level) and used the one modified by REWIND and now I'm getting a 1200x502 resolution at 24 fps for about 14 seconds on my 550d. Thats very usable.
No pink \ purple frames where recorded.

[deletedAcc.0021]

#10
http://www.magiclantern.fm/forum/index.php?topic=7058.msg59045#msg59045

Very interesting .. .thanks for pointing this out.

[1%]

Nothing broke in ~2 years. I also have movie remap too Asserts are patched for H264 mainly and the code is there for anyone to review.

With sraw though some people shot in it because they forgot to change it back.

[Andy600]

I think there is a big misconception among some users and some misinformation about Tragic Lantern (inc 2.0) that makes users more nervous about trying it.

I've never had any major issues with Tragic Lantern on the 600d or 50d, infact I only shoot with Tragic Lantern. It has some nice camera-specific optimizations and features that the Unified code doesn't have. The only reason it is deemed 'unsafe' (although I wouldn't use that word myself) is because some features leave the camera in a hacked state until it's rebooted. The new dual ISO feature is 'potentially' more dangerous than anything introduced in Tragic Lantern. It's all down to the level of risk you are personally willing to take with you camera.

[deletedAcc.0021]

Nothing broke in ~2 years. I also have movie remap too Asserts are patched for H264 mainly and the code is there for anyone to review.

With sraw though some people shot in it because they forgot to change it back.

I was surprised to see the comment by Alex, but I understand his POV.  Its good to know that he's looking out for the majority.

I've used TL2.0 on several commercial shoots without any issues and have recommended it to others who where interested in raw for the 600d.

I don't understand enough about the code to make a call either way, but will heed Alex's warning as I do not use raw except for personal projects.

[1%]

I'm not surprised, he likes things one way, I like things another way, lol.

He is careful about making things user proof and I'm more results oriented. Also some things are camera exclusive and he wants everything to work across all platforms (ie building unified except individual binaries). He is the better code by leaps and bounds but now some digic V things pushed digic IV too hard.. ie the raw overlays are really killing 600D (90-100% cpu usage, pink frames in MZ).

Really nobody is perfect and what you should do with any new build, be it nightly or mine is try it the day before to make sure there are no bugs BEFORE you bring it on a commercial shoot. Its not like your camera will brick but if you're getting err 70 on a specific feature you need it will be too late to fix it while on set.

[deletedAcc.0021]

I just tried the latest nightly with raw capability. Modules load fine and raw recording works.  The only problem I'm having is I'm getting large amounts of magenta frames with this build compared to no magenta frames with TL 2.0 with the exact same settings.

I take it this is a memory or buffer issue?

[iaremrsir]

Is anyone else getting crazy amounts of dead pixels on their footage?

[iaremrsir]

I just tried the latest nightly with raw capability. Modules load fine and raw recording works.  The only problem I'm having is I'm getting large amounts of magenta frames with this build compared to no magenta frames with TL 2.0 with the exact same settings.

I take it this is a memory or buffer issue?

I thought TL 2.0 was the nightly for 600D. Are you using the ML nightly from http://www.magiclantern.fm/forum/index.php?topic=3072.0

[deletedAcc.0021]

I thought TL 2.0 was the nightly for 600D. Are you using the ML nightly from http://www.magiclantern.fm/forum/index.php?topic=3072.0

Yes, the nightly's have raw_rec modules enabled, but something needs tweaking as the magenta frames are prevalent in even the lowest resolutions.  Time will tell....>

[1%]

Its the sync/cpu load... can't measure on the nightly because taskman is disabled   

The problems went from repo -> me, not the other way around.

[Drewton]

Have a 95 mb/s card, setting the resolution to 640x480 (not the RAW video resolution though) always fixes it.

[a1ex]

Here's the correct way to fix pink frames: http://www.magiclantern.fm/forum/index.php?topic=6740.0 (under research)

The problem is present on all cameras, just the probability of visible side effects is different (ranging from say under 0.1% on 5D3 at common resolutions, a little higher at 3K, and goes all the way to 100% on 60D in crop mode, for example). Enabling overlays is just changing the timing (I bet the problem is a race condition), and here it only happens to increase the probability (but this doesn't mean it's the cause or the solution).

Using the 640x480 mode also changes the timing (the probability of Canon firmware requiring EDMAC access at the same time as ML is much lower, so it's a lot less likely to get pink frames in that mode).

The test from don't click me is relevant for pink frames - when that one will work without side effects in LiveView, the pink frames will be gone.

[1%]

When raw video is on I get pink frames in MZ. Also Mz or HDR can cause err 70 in EVF state, patching this causes really slow updating instead of the error. Plus zebras like that video a while ago.

   if (self == EVF_STATE && old_state == 5) { 
      //600D Goes 3 - 4 - 5 5 and 3 ever 1/2 frame
        lv_vsync_signal();
   }

600D can sync MZ like that, i thought to turn it off maybe a race condition with this and evf_state_sync?
But did not help.

Moving things off onto display state helped but then modules/raw isn't synced. EVF + dstate both seem to fire more than once a frame in all modes.

[a1ex]

vsync should fire exactly once per frame.

[1%]

Yep, thats why EVF sync didn't work on 600D.. but syncing on old_state=5 works.