Hi All

Sent an e-mail to DJI yesterday trying to explain to them the issue with the compression settings in the Inspire1. I was baffled by the response. No reflections or answers regarding my questions. They simply want me to do a RMA and claim that the unit is in need of repair. I do not share this opinion. I still believe this thing needs to be adressed ASAP in the firmware. I cant use it for professional work and I should not really have to wait for a new gimbal and camera get released for the I1. So, I filmed a test today and I would like to ask you guys, the community for help!


I have uploaded a native H264 4K video from the Inspire1 that i recorded today. What I need to know Is if you see what I see, flickering/strobbing "effect", like small flashes in the image every 8th frame due to the GOP sequence. Its noticable in the water and in the textures of the trees in the foregound. Do you experience the same issue with the video you produce? DJI seems painfully unaware of this and is scares me that they simpy issue an RMA instead of communicating with their customers.




Flickering video(about 110mb)
http://we.tl/tLYoDRpMHz



regards
Mike


My e-mail to DJI

Hi There Pasting my posts from the forum in an e-mail, since I have not got any reply Pretty much everything with the Inspire1 hardware Is great. But the one thing that keeps me disappointed every time I look at the footage is the settings in the H264 compression of the Inspire1. First of all you really need to enable I-frame recording and push the bitrate as much as you can. Looking at my footage it’s obvious that the compression artifacts are smoothing small details everywhere in the image, looking like wax. The GOP sequence also limits me from doing any fast pans or tilts without major compression problems. H264 compression will actually look great, as long as you have the bitrate supporting the resolution, and right now they are not in sync. With long GOP(8 frames) sequences the H264 compression gets terribly bad. You get what is called residual compression artefacts that stay between I-frames. Basically the noise freezes for 8 frames at a time, then updates when a new intra frame is encoded. Creating the stuttering effect in the footage. So this means that some of the footage actually has a lower, perceived framerate, than recorded. All of this is caused by the compression settings in the camera. The image from the camera without the H264 compression will probably look gorgeous. There is no magic filter or noise reduction that can compensate for a low bitrate destroying the details produced by the Inspire 1 H264 compression. Basically thats what it is, the problem is the compression of the material. No matter how you adjust the sharpness, LOG or any other setting for that mater can make the footage look better. Please, I bought this hardware for professional filming and I can’t use it for more premium work. Its just a waste of technology as it works now. Every firmware update you release to the inspire might give it more stable GPS, better compass and so on. Everything boils down to this, every Inspire feature request ends up in the camera in one way or another. Whats the point with all the updates if video compression still looks terrible…. DJI – Need to have for usable video recordings Higher and Constant Bitrate (at least the double amount) Intra frame recording

Mike, I'm not an expert by any stretch of the imagination. However, I do see the flicker you're speaking of.  I often have something like this happen with my footage but have little knowledge on why or how to separate the potential issues.  Sometimes I think it's related to the props and wonder if a lens shade could be of help, other times I tend to think it's related to my camera settings and environment of what I'm shooting.  Ie. moving along trees, following a subject with trees in the background, moving past patterns in the shingles of a roof, etc.  I tried converting your file to a Pro Res 422 HQ and i don't think I noticed much difference.  Feel your pain, I'm just learning and trying my best to apply sound techniques, playing with fps, LOG, shutter speeds.  I'm lost at the moment when it comes to sharpness settings etc.  I look forward to Jim's response to your issues.

I looked at your film, just couldn't see the flickering you describe.  

Is your screen/ computer fast enough to display high resolution pictures ?

Perhaps  Jim is the guy down in OZ to comment, or Scooter.

We all have this issue, its the compression and how it handles the details. DJI wont respond to this because they are aware of the issue, but AFAIK cant do anything about it because its a hardware limitation.

Pro tip : Record in manual, not auto mode. Another problem with this camera is that in auto mode, exposure is auto adjusted, but you can clearly see the stepping between two shutter speeds. Thats because DJI didnt do any smooth easing when auto correcting shutter speed.

I hope DJI is reading this...and fixing it...

i totally agree with you mike. i see the cruel flickering in front of the trees.  i'am a bit disapointed too. perhaps an fw update will fix it - but i can't believe. hopefully there is in the near future a better cam (M43?). flickering and artefacts suxx at the inspire1 cam!

check my video:


@Ozren:  Manual mode will not fix the main problem. but it helps a bit to minimized the exposure steps.
greets, Uwe

I'll add that I do see a difference between my two screens.  My Macbook Pro Retina display shows less flicker than my 9 year old external 20 something  Mac display.  I guess it's time for me to upgrade to a 5K iMac or ???

Thanks for confirming what I suspected, really appreciate you taking the time looking at the footage! I just hope that DJI somehow can tweak the settings in the camera in a future FW. I mean, from my perspective this is a rookie mistake done by DJI and they have to fix it, I believe they owe It to us. This is what happens when you are more of an engineer than focusing on the output quality of the video it produces. I wonder if the DJI R&D team have anyone onboard their team that evaluates the quality of the footage when developing a new product like this. They really should have, Its like they just didn't care or just didn't see it.

Please DJI, give us something, a reply, anything!

I want to be able to use the Inspire1 as a professional tool for creating stunning videos that gives the best quality that H264 can produce. Right now we are not even close.


All the best
mike

I want to be able to use the Inspire1 as a professional tool for creating stunning videos that gives the best quality that H264 can produce. Right now we are not even close.

That pretty much says it all.

The big question is whether the H.264 encoder settings can be changed in firmware (or ideally if a firmware update can bring them out to the UI so they can be user-set).  If they were smart at the design stage that should be true.  Wish someone from DJI would tell us (but, of course, they won't - unless they actually make the change).

I have noticed these issues to. Flickering in detailed subjects and noise in darker areas of the images. I have been a broadcast cameraman for over twenty years and have used most of the top end cameras over that time. I have also become a bit obsessed when it comes to picture quality having used these cameras. I realise that the camera on the Inspire is not expensive and is bound to have it's limitations but it should be competing with the Gopro 4 all the way in terms of the above issues.

I don't want to jump the gun here but have had what appears to be "some" success today resolving these issues. Up until now I have been using the stock Lexar cards which come with the Inspire thinking it should be fine for it's intended use. Today I got hold of some faster cards and did a quick test with them against the stock Lexar. Shooting the same shot with identical settings they gave very different results. The image from the faster cards was much softer than the other and didn't appear to have all the noise in it that I have found with the stock cards. There was also noticeably less flickering in the image although it is hard to tell whether it has gone completely until I do a more comprehensive test.

I must say, I was very sceptical about different cards making any difference to image quality but from what I have seen so far with a quick test it seems that they do.

I had the issue too..

Shot yesterday at 2160p24 Log on the stock Lexar-Card. Manual exposure. Graded to match the footage of a a7s.
The flickering is cleary visible in the background  and grass. It is extremely visible in the hue and saturation channel (see end of video).

https://dl.dropboxusercontent.com/u/26164456/FlickerI1.mp4

I will try a faster card in the next days.
Arctic, which card have you used for your testing?

Yep, this is all completely normal.

I tested it with another SD-Card. Samsung 64 GB pro with 90/80 MB/s Read/Write speed.
No difference to the stock card. Ugly flickering Video.
Very dissapointing.
Please DJI, give use higher Bitrate Video with less compression artifacts!

We have exactly the same situation with the Phantom 3. Every eight frames there's an abrupt change in detail and noise and even a bit of luma, I think, which creates a relatively faint but perceptible flickery quality to the whole image, particularly in dark detail. It makes bad video, and it doesn't happen with 4k in the GoPro.

I believe that DJI should not take its products to events like NAB if it is willing to allow these kinds of compression artifacts in its footage.

However, rather than yell a lot, I'd rather find out how others have coped with it. It seems reduced or non-existent when the camera's moving fairly quickly, and it may be much less significant in shots with less detail. How are other people dealing with it? Are there workarounds? I've tried transcoding with various pieces of software, and denoising with Neat Video, etc. But nothing has made a difference. Is it just necessary to keep the image on the move?

Thanks!

Mike

I have gone through 2 inspires so far and both of them suffered from this issue, big time. I, like you (and surely hundred/thousands of others) wrote DJI about this issue soon after I noticed it. The compression in this camera is miserable, at best. Different cards have yielded no difference in results. I am not an expert, but I would be surprised if they are able to fix this problem through software updates, as I think this is a limitation of the hardware. It is hard enough to get a successful (round trip) flight out of this platform as it is, so DJI could at least be kind enough to put a decent camera on this thing so that we at least have some decent footage to look at while our copters are hanging out at HQ for 6-8 weeks at a time. I will be receiving my third I1 tomorrow and hope this one will be better, but I'm certainly not holding my breath. Luckily I have 6 other aerial rigs to use for work, so I am not in the same trouble as those of you who are relying on your I1 for income. The bottom line is I hate paying for anything that doesn't work, and then having to wait around while the manufacturer tries to figure out how to actually make the product live up to the marketing that they sold me months ago. Sorry, ranting again...

I tried a faster card as set out above recently. When I first put it in I seemed to get a different result between it and the stock card but having tested comprehensively in different circumstances the issues are still apparent. I have no explanation for the difference between the cards on the first tests but still have the shots and it is very noticeable.

So we are where we are with the camera. I have two Inspires and they are both exactly the same in terms of the flickering issue. It is much more noticeable in subjects of high detail like grass or trees. In all honesty it renders the footage completely unusable for professional applications. The way things stand at the moment I could not use this platform for any of my clients. This is very annoying as I like many have invested a fair amount in these machines having bought two of them. I am just hoping that DJI can be a bit more transparent and either let us know whether this can be fixed in the current camera (very doubtful). Or let us know if they have a definite plan for a future camera and if this may happen anytime soon. The other hope is that someone or even DJI develop a gimbal to accept a better camera.

I, and I suspect many others would be quite happy to pay a considerable sum for a decent camera for the Inspire platform that performs at a professional level. Failing this I will have no other option than to move to another platform which is a real shame as the Inspire is a great peice of kit in almost all respects apart from the camera which seriously let it down. For anyone using this at a professional level the results out of the camera are the be all and end all and if they are unacceptable the platform becomes a recreational toy no matter how well it flies

It would be really, really helpful if someone from DJI could comment on this subject please

Arctictern Posted at 2015-5-19 17:54
It would be really, really helpful if someone from DJI could comment on this subject please

Yes it would.  Unfortunately it would also be completely uncharacteristic of them,  which is a shame, because it is making more and more customers decide that their future purchases will be from a more responsive company.

Hello! Could anybody share more samples of video?  (esp. without rotations, just moving forward). I need to find out how trackable it is for future 3d pipeline... (going to use pftrack+nuke).  Thanks!

ugranzow@web.de Posted at 2015-4-23 04:47
i totally agree with you mike. i see the cruel flickering in front of the trees.  i'am a bit disapoi ...

I was flicking around the play back settings on youtube and this clip sadly looks better at 720p then it does on 1080p or 4K ...

zappbn Posted at 2015-5-22 19:40
Hello! Could anybody share more samples of video?  (esp. without rotations, just moving forward). I  ...

Hi Zap,

It's useable for tracking. The main problem is the lens distortion.

I tried a lot of things. Lens correction in Mocha, Nuke. But I couldn't get it right.

The workflow I ended up with was correcting al mij footage in Photoshop using the lens correction module. Adobe has a lens profile for the Inspire now. Or use the Fc350 profile.

Just be sure to make a good output profile when exporting it.

The compression sucks bigtime. Indeed it's an issue that DJI has got to solve. Starting with upping the bitrates would be a good beginning. 20, 40 and 60 are simply to low.For some scenes I shot, I corrected and smoothed them with RE:visionFX De:Flickr. And got some decent results, without lossing to much details.

a little test in here : https://www.dropbox.com/s/76nqrsdzxt7lvh1/quick_test.mp4?dl=0

regards,

Peter

DJI did a good job since latest fw update. no more flicker seeing. iam happy now with film quality! android bugs are also removed! thanks dji!

I watched the video on an Asus 4K monitor, and a really fast video card, on a quad core PC, and didn't see "flicker".  Unless you were talking about moire.  I did see tons of moire at almost every straight line, like the docks.  The sharpness was almost enough to make my eyes bleed.  Try turning sharpness down to -1 or even -2 in the camera.  Throw an ND filter on.  On a day like you had in the video ND16 or even ND32 wouldn't be out of line.  

Check out this thread.... lots of really good tips here.   http://forum.dji.com/thread-9738-1-1.html


Edit:  I watched the video again and slowed it way down.  I did see what appeared to be intermittant exposier changes (almost like a darkening flash).  Is that what you are taking about?

Just got an Inspire 1 this week, very impressed with the aircraft but the camera's not blowing me away! Here's a short video shot in pretty dull conditions, I was just trying the Inspire out and testing the various modes, etc. This was shot in 4K/30p D-LOG, -1 sharpness, -3 contrast and saturation. Edited onto a 1080/30p timeline in FCPX and graded with my own log plugin made in Motion. There's a lot of flicker going on flying over the heather, and the image is far noisier than I was expecting. I've seen this same effect with my Hero3 Black in 1080 but not with my Hero4 Black in 2.7k. OK, the conditions weren't great but quite typical of what I film. I think an upgrade to the X5 camera will be sooner than I was planning, the compression on the X3 is horrible!

https://youtu.be/veg8xeh3MIg

X5 has the same horrible bitrate at 3.5% of sensor 60 mbps