4K (to HD) Video workflow...

[AeroJ]

Ok, I am having to revisit this thread, on account of a continuing video problem that as yet I am unable to resolve or find any information about !
I made this video to demonstrate a barometer problem / descent issue, but it also turned out to be highly demonstrative of a rather more worrying problem I am getting every time with 4K video from the CGO3+. As you can see from the above, I have solved the movement juddering by transcoding, but what remains are these annoying 'blurry dim flashes' every 1 second throughout this video, and on every 4K video I have ever taken with the CGO3+ ! Doesn't happen at all with 1080 source footage as far as I can see.

So, are you seeing what I am seeing ? It is worst at the following times in the video below:

1:11 - here the dimming flashes are almost in time with the music !
1:34
2:22
2:58 - very much ruining my nice panning shot there !

...but it's actually going on most of the time, just very subtly, but definitely to the extent where it is ruining my videos ! Note I am not talking about the youtube compression that regularly blurrs out my near-ground level shots, but the regular pulsing dimming that goes on in addition to that !

I can put up with all sorts of flight problems with the Typhoon H if I can only get decent video out of it in the end, even if that takes some effort, but knowing as I do that this particular problem is in the source footage too (the grade makes it worse / more noticeable, but it is there in the files directly out of the camera) and as such might be unsolvable, so I am beginning to think that unless my CGO3+ is broken, I may have to return, or sell the H and try and find some other platform where I can reliably get decent 4K footage. As much as it would gall me to go back to horrible DJI, the Mavic 2 Pro does produce incredible footage, and seems like it might just... work.

So is this every CGO3+, or just mine that does this do you think ?

One last thought - Every time I have done a 4K video, I have had one of those cheapy Neewer ND filters on. I don't suppose that could have anything to do with it could it ?

Thanks guys

J

 

[SethB]

I used these settings initially, which certainly produce smooth 4K mp4 output, but looking at the file sizes, the original one off the camera was 1.65 GB, and the mp4 I output was 5.45 GB, so I guess quality was set too high.,,,
View attachment 11014

An aside on configuring Handbrake:
The snap shows that the Constant Quality method was chosen, with a value of 1 on the Quality slider. I’d suggest trying a value of 20 for transcoding to MP4. That will preserve quality and reduce file size quite a bit.

If you *are* interested in simultaneously resizing to 1080, Handbrake has an excellent scaling method, Lanczos, it’s really state of the art. Though, as pointed out in this thread, preserving 4k into your edit means you can do punch-ins, zooms, and reframing with no loss of resolution when you deliver in 1080p.

Handbrake is really, really good at MP4 conversions. None better, really, and, it it includes the best scaler (Lanczos), the best deinterlacer (Yadif), and the best h264 encoder (x264). And, it’s free!

 

[rdonson]

Ok, I am having to revisit this thread, on account of a continuing video problem that as yet I am unable to resolve or find any information about !
I made this video to demonstrate a barometer problem / descent issue, but it also turned out to be highly demonstrative of a rather more worrying problem I am getting every time with 4K video from the CGO3+. As you can see from the above, I have solved the movement juddering by transcoding, but what remains are these annoying 'blurry dim flashes' every 1 second throughout this video, and on every 4K video I have ever taken with the CGO3+ ! Doesn't happen at all with 1080 source footage as far as I can see.

So, are you seeing what I am seeing ? It is worst at the following times in the video below:

1:11 - here the dimming flashes are almost in time with the music !
1:34
2:22
2:58 - very much ruining my nice panning shot there !

...but it's actually going on most of the time, just very subtly, but definitely to the extent where it is ruining my videos ! Note I am not talking about the youtube compression that regularly blurrs out my near-ground level shots, but the regular pulsing dimming that goes on in addition to that !

So is this every CGO3+, or just mine that does this do you think ?

One last thought - Every time I have done a 4K video, I have had one of those cheapy Neewer ND filters on. I don't suppose that could have anything to do with it could it ?

Thanks guys

J

What is your camera setup??? If you're on AUTO WB and/or AUTO Exposure that could explain a lot.

Obviously high quality ND filters are better but please share how you've set up the camera.

 

[AeroJ]

What is your camera setup??? If you're on AUTO WB and/or AUTO Exposure that could explain a lot.

Obviously high quality ND filters are better but please share how you've set up the camera.

Sure: Camera settings were as follows :

White Balance: Cloudy (locked)
Exposure: Manual, and varied throughout the flight between 1/60 and 1/125.
ISO: 100, later altered in-flight up to 150 when I was panning directly down and needed some extra brightness.
Image mode: Natural
Dimensions: 3840 x 2160, '30' FPS (actually 29.97).
Files reported to be 50MB/sec bitrate

Let me know if I missed anything ! And thanks again for trying to help !

 

[PatR]

Were the in flight camera alterations a time match to your flickering issue? The only time I’ve experienced that is when changing camera settings in the middle of a take, or when using auto white balance. Both are things I no longer do. Once the camera is set no changes take place once the in flight shooting is initiated. Changing EV during filming will cause a step in the lighting every time as well.

 

[AeroJ]

Were the in flight camera alterations a time match to your flickering issue?

Thanks Pat. Alas, no. Exposure was set on the ground, and then not altered at all until about 5 minutes in. I don't see any sign of the flickering until launch, but then it remains fairly constant to one degree or another for the rest of the flight, and the one after it.

I will do a flight tomorrow without the ND filter, just to rule that out of the equation once and for all !

 

[rdonson]

Another think that might be worth checking is your SD card. It needs to be able to handle the write speeds necessary for 4K video. A U3 V30 card is required for good results. Sandisk cards with this rating have generally worked well.

 

[AeroJ]

Another think that might be worth checking is your SD card. It needs to be able to handle the write speeds necessary for 4K video. A U3 V30 card is required for good results. Sandisk cards with this rating have generally worked well.

Interesting you mention that - I am NOT using a U3 card - just a regular Class 10 SanDisk. But I figured if its fast enough to produce smooth footage and not drop frames on recording or playback, then it must be up to the task right ? And I would not expect errors in data transfer speed to show up as video artefacts like I am getting. But I am desperate to sort this out, so that is one of the things I will try next.

 

[FlushVision]

Interesting you mention that - I am NOT using a U3 card - just a regular Class 10 SanDisk. But I figured if its fast enough to produce smooth footage and not drop frames on recording or playback, then it must be up to the task right ? And I would not expect errors in data transfer speed to show up as video artefacts like I am getting. But I am desperate to sort this out, so that is one of the things I will try next.

I agree with @rdonson in that the 'informed' among us advocate a U3 card is best to use especially when shooting 4K. However, before getting my current U3 card I used to use a run-of-the-mill Class 10 card and I've noticed that the 4K footage I previously shot with that card shows no problems when played on my new computer. I used to think the problem was with the card...it turned out that my problem was with my old laptop.

 

[AeroJ]

I used to think the problem was with the card...it turned out that my problem was with my old laptop.

Lols Yes, this is what holds me back from buying a new card. I think I am in the same situation as you - my class 10's are working on any machine good enough to play back 4K video, and I think that video would be stuttery, or absent after the first few frames if the card wasn't coping.

 

[rdonson]

I can't speak for prices in the UK but Amazon US has 32 GB Sandisk Extreme Pro microSDHC Memory Card Plus SD Adapter up to 100 MB/s, Class 10, U3, V30 for $20. That seems pretty reasonable.

 

[FlushVision]

I can't speak for prices in the UK but Amazon US has 32 GB Sandisk Extreme Pro microSDHC Memory Card Plus SD Adapter up to 100 MB/s, Class 10, U3, V30 for $20. That seems pretty reasonable.

I think they are a bit dearer in the U.K. on Amazon (but I haven't checked). I bought my U3 card at the local Tesco supermarket a couple of months ago. I forget how much it cost but I seem to recall somewhere around £25.00.

But that was before I got my new computer. I suspect that if I'd have had this new computer before I bought the card, I probably wouldn't have splashed out that £25.00.

 

[AeroJ]

Yep, I'm with Flush there, and sticking with my class 10s for the moment. Just been out to do another load of flight tests. This time I have tried all the 4K frame rates, with no ND filter, to see if the problem is still there. Just about to review all that footage...

 

[FlushVision]

Yep, I'm with Flush there, and sticking with my class 10s for the moment. Just been out to do another load of flight tests. This time I have tried all the 4K frame rates, with no ND filter, to see if the problem is still there. Just about to review all that footage...

One thing is for certain when it comes to stuttering or dropped frames...well three things actually.

Causes
The computer simply isn't powerful enough to cope with what is being asked of it;

The editing program isn't suitable for the hardware that it is running on, or there is a problem with that editing program;

The card write speed isn't fast enough.

The reason why the 'experts' advocate changing to a faster U3 card when advising about video stutter is simply because it is the cheapest option to pursue unless the person is running a free program. Far cheaper than buying a newer faster computer. I used to, and to some extent still do, advocate for a U3 card. But my experience of viewing 4K video recorded on a standard class 10 card on my super-duper computer has made me change my stock advice on the subject from simply saying: 'Get a U3 card', to 'Get a U3 card unless you are imminently going to get a new computer and see if your class 10 card works better on that'.

Just my opinion.

 

[AH-1G]

Interesting you mention that - I am NOT using a U3 card - just a regular Class 10 SanDisk. But I figured if its fast enough to produce smooth footage and not drop frames on recording or playback, then it must be up to the task right ? And I would not expect errors in data transfer speed to show up as video artefacts like I am getting. But I am desperate to sort this out, so that is one of the things I will try next.

@AeroJ
I recently purchased a class 10 card after I misplaced my other U3, boy does that class 10 suck!
Got me a PNY 32GB Eite U3. works soooooo much better.
And wouldn't you know it, 3 days after the new card purchase, I found my Samsung U3, It was in my other blue jeans pocket.
I swore I checked it, it must have been a gremlin who borrowed it.

 

[AH-1G]

My ND filters were about 30 dollar range, no issues.

 

[FlushVision]

@AeroJ
I recently purchased a class 10 card after I misplaced my other U3, boy does that class 10 suck!
Got me a PNY 32GB Eite U3. works soooooo much better.
And wouldn't you know it, 3 days after the new card purchase, I found my Samsung U3, It was in my other blue jeans pocket.
I swore I checked it, it must have been a gremlin who borrowed it.

My class 10 card that I used to use was a very high quality card so that may figure in it's ability to record 4K without stutter. I've no doubt that some lower quality class 10 cards may not be able to handle 4K as well as higher quality cards...which is why I still advocate for the use of U3 cards but with the proviso that I explained in my above post.

 

[PatR]

If we think U3 card prices are high, just wait until you see the prices of the new Sony and Belkin ultra high write speed cards. Guaranteed write speeds of over 200mb/s with prices starting out over $100.00. Belkin is so proud of them they put a serial number on them.

 

[rdonson]

I've seen the new Sony SD cards - they are rugged and can survive water and all sort of torture.

However these Sony UHS II SD cards are more reasonably priced - $25. I use these in my Fuji camera. Note: these are NOT microSD cards

 

[AeroJ]

I have done some maths. The original footage I get out of the CGO3+ needs a write speed of no more than 6MB/second, and class 10 is certified to at least 10 MB/Sec, and in write tests I did this evening is actually achieving more like 17 MB/sec when I copy a file to it. This pretty much convinces me that the card isn't the problem.

Went out and did another 2 test flights this evening, and tested all the 4K video modes, and without an ND filter, but very disappointed to see that the problem remains in all those modes.
But try as I might, I cannot find any other example of this problem happening in other people's 4K footage, so I must now assume this a problem with my specific CGO3+ and I will try and get a fix or new unit from Yuneec under warranty.

Thanks to everyone that tried to help so far...