just found why my 4k is jerky

[Dale D]

I thought I had purchased a high speed Sandisk SDXC.. till I just discovered the the write speed is 90Mbs and not just the headline read speed (160mbs) I even lowered the fps but it still doesn't help with Jerky capture (I did try the footage on my fast pc and it is still the same. (the footage to the phone cache is low res but not jerky at all)

I have since seen this advertised: SanDisk Extreme Pro, Class 10 U3, 275MB/s Read & 100MB/s Write Performance microSDXC Memory Card.. However is 100mbs write still only just on the edge of acceptable for the Mini 2at 4K?

Any recommendations please?

Thanks very much

Here is the card I have been using for 3 years, both in the Mavic Air 1 and now in the Mavic 2 Pro.

Dale
Miami

 

[SkiProiii]

All cards are not the same despite stated ratings. Generally get what you pay for here so I recommend the SanDisk Extreme Plus V30 A2 (U3 being another indicator as with V30, V60 also indications of true throughput).

I have also used the Lexar 667x too without issues for 4K in the drone and Sony A6400. I am sure there are others just as good but if something isn’t broken, I don’t “fix” it and just pay a few bucks more! They come on sale and 128GB seems to be the sweet spot on price/capacity currently.

Playback can also be the software used - some use the CPU, others use video cards. Try the VLC player - free software, and very good for auto optimization of your set up.

From DJI Mini 2 Specs (most recent): Recommended microSD Cards

• 16 GB: SanDisk Extreme; 32 GB: Samsung Pro Endurance, Samsung Evo Plus, SanDisk Industrial, SanDisk Extreme V30 A1, SanDisk Extreme V30 A2, SanDisk Extreme Pro V30 A1, SanDisk Extreme Pro V30 A2, Lexar 633x, Lexar 667x
  64 GB: Samsung Pro Endurance, Samsung Evo Plus, SanDisk Extreme V30 A2, Lexar 633x, Lexar 667x, Lexar 1000x, Lexar High Endurance, Toshiba EXCERIA M303 V30 A1, Netac Pro V30 A1
  128 GB: Samsung Evo Plus, SanDisk Extreme V30 A2, SanDisk Extreme Plus V30 A1, SanDisk Extreme Plus V30 A2, Lexar 633x, Lexar 667x, Lexar 1000x, Lexar High Endurance, Toshiba EXCERIA M303 V30 A1, Netac Pro V30 A1
  256 GB: SanDisk Extreme V30 A2

 

[inno]

Actually, GadgetGuy, I believe every byte is composed of 8 bits. A megabyte (MB) is 8 times the size of a megabit (Mb). A capital B is the byte and the lowercase b is the bit. It is confusing I will admit.

Actually to keep it simple

1 byte = 8 bits
1024 bytes = 1 kilobyte (1k)
1024 kilobytes = 1 megabyte (1mb)
1024 megabytes = 1 gigabyte (1gb)
1024 gigabytes = 1 terabyte (1tb)

Actually, GadgetGuy, I believe every byte is composed of 8 bits. A megabyte (MB) is 8 times the size of a megabit (Mb). A capital B is the byte and the lowercase b is the bit. It is confusing I will admit.

a byte is the smallest unit of data on a system in general. 1 byte = 1 ASCII character. 2 bytes = 1 UTF-16-character. an unsigned byte can hold the values 0-255.

example
"a" = 1 byte
"A" = 1 byte
2 = 1 byte
16 = 1 byte (not 2 bytes because it's a numeric value)

ASCII character showing the binary (8 bit = 1 byte) value


sorry one last thing to clarify is mbps, originally a term used to define internet speeds. but be careful, there are two meanings

Mbps = megabits per second
MBps = megabytes per second

the diff is the letter "b", uppercase = (megabytes), lowercase = megabits.

in summary
For the purpose of this thread, i have found that the majority of issues with video playback is with the capabilities of the computer or device your viewing it on. i know with at least the DJI Fly app, if your SD card is too slow the program will display an error message regarding the capabilities of the sd card if you exceed the cards capabilities based on your camera's settings.

hope this was informative, happy and safe flying

 

[mjiggens]

Definitely sounds like a playback issue. However, it's not really about the card speed or bit rate - though as the other ops have said its not good practise to try playing it back from the card in the reader as there are various things that can slow this down - copying the files to your internal (or a fast external) hard drive is a better idea. Sounds to me like it is the de-compression your system can't handle. H264 files are quite CPU intensive to decode for older PCs - H265 even more so - doubly so in fact... Ironically, something like a modern iPAD will play these back easily - because the H264/265 decoding is handled in "hardware" by a specially designed part of the Arm CPU. Most PCs/Macs have to do this the hard way in software. As an example, my 2016 MBP will happily play 4k H264 100mbps back smoothly, but completely gives up with 4k H265 at 150mbps. But it's NOT the bit rate (data rate) - it will happily play 4K Apple ProRes which has a data rate of over 500mbps! - assuming the drive is fast enough - because this is a much less compressed format. H265 is a brilliant way of recording loads of data in a small file, but it does have its down sides. Upgrading your graphics card may not help either - unless you're using a programme which supports GPU acceleration of H264/265 decoding such as the latest Premiere Pro. I should add I'm a Mac user not a PC expert (any more); there may be other solutions -such as transcoding your H264/265 files to a format that your PC can handle. Or it may just be as simple as sticking to recording H264 rather than H265... (In theory H265 is twice as space efficient as H264 - so H265@100mbps "should" have the same quality as H264@200mbps...

 

[Dave Maine]

The other major consideration on 4K playback on PCs is the codec selected for recording on the drone. The easiest choice is the H.264 codec which places the least demand on the playback computer. H.265 is a whole different animal, and really stresses most PCs.

 

[Grazuncle]

The other major consideration on 4K playback on PCs is the codec selected for recording on the drone. The easiest choice is the H.264 codec which places the least demand on the playback computer. H.265 is a whole different animal, and really stresses most PCs.

thanks..

can you select either as an option on the Mini 2?

 

[Dave Maine]

I don't know about the mini 2, P4, P3 and Air 1 all allow it.

 

[RC_Adik]

Per the manual, (v1.2) for the M2 it is MP4 H.264/MPEG-4 AVC. I don't recall anything being selectable.

 

[Dave Maine]

That is a good choice. If that doesn’t play properly it is a problem in the PC system.

 

[SkyeHigh]

Almost correct:

1 byte = 8 bits
1024 bytes = 1 kilobyte (1KB)
1024 kilobytes = 1 megabyte (1MB)
1024 megabytes = 1 gigabyte (1GB))
1024 gigabytes = 1 terabyte (1TB)

As shown above capitals should be used in the abbreviations.

‘a byte is the smallest unit of data on a system in general.’ No, a bit (binary digit) is the smallest unit of data.

‘sorry one last thing to clarify is mbps, originally a term used to define internet speeds.’

It has no origin related to the Internet at all. It is a term in common use since the 1950’s to describe the bit rate per second of a serial data stream in a communications system. And using your own example it should be ‘Mbps’.

 

[Arnold LeVine]

Also, if you shoot with H265 instead of H264, you really need a computer with a very high end graphics card. A high end graphics card and high speed processor is a video shooters best friend. Especially if you want to use the free DaVinci Resolve software

 

[tribar]

Turn OFF hardware-decoding in your playback software.

in VLC it's:

 

[nealix]

I thought I had purchased a high speed Sandisk SDXC.. till I just discovered the the write speed is 90Mbs and not just the headline read speed (160mbs) I even lowered the fps but it still doesn't help with Jerky capture (I did try the footage on my fast pc and it is still the same. (the footage to the phone cache is low res but not jerky at all)

I have since seen this advertised: SanDisk Extreme Pro, Class 10 U3, 275MB/s Read & 100MB/s Write Performance microSDXC Memory Card.. However is 100mbs write still only just on the edge of acceptable for the Mini 2at 4K?

Any recommendations please?

Thanks very much

Jerky footage is almost ALWAYS due to panning, and panning too fast. Look closely at all the youtube drone videos and notice how few are using panning. But if you want it to be smooth, you gotta learn about this topic:

RED Tools | RED Digital Cinema

Convenient, multipurpose tools designed for use by filmmakers and camera operators to outline best practices in camera set-up for a variety of shooting situations. Available tools: Crop Factor, Recording Time, Flicker Free Video, Depth of Field, Panning Speed and Expusure.

www.red.com

and

RED.com

www.red.com

If you are going to use panning at all, it turns out the speed needs to be a LOT slower
than we would normally think.

Neal

 

[Bodkin's Best Photography]

Also, if you shoot with H265 instead of H264, you really need a computer with a very high end graphics card. A high end graphics card and high speed processor is a video shooters best friend. Especially if you want to use the free DaVinci Resolve software

My father plays 2GB 1080p x265 files on a old prebuilt computer from 2014 with no graphics card, 4GB ram that's running windows 7. They're really not all that demanding. Now if it's a x265, 4K, 60fps video running at 100mbps then yeah, there will be issues.

 

[simsurf]

well.. (hides head in shame)... presumption and bad YT advice is a terrible thing and i have learned this today.

I improved the playback of the 4k footage by bypassing my USB3 hub and USB3 card reader by putting the microsd card into a plain USB (standard USB - only thing i have presently) thumb sized reader directly into a USB 3 slot on my 8 core i5 desktop pc (one year old) it played a lot better although still froze and jumped.. (not exactly jerky as my thread, perhaps misleadingly) indicated.. I'm now guessing this is a playback issue and not a recording issue.

So i got out my Lenovo Yoga 520 convertible laptop (2 yr old) with lowly Pentium 4415U cpu and plugged the microsd to SD card adapter into its built in slot and the thing runs smooth as butter! no jerky playback at 25 fps in bright sunlight and no ND filters.

To say I'm shocked is an understatement! I have ordered a USB3 microsd card adapter in the meantime but now i have to figure out what to upgrade in my pc to handle this 4k footage better..

ps 2.7k is fine as it is in my pc

Your playing the 4k footage from the SD card? Of course it doesn't play smoothly. Download it onto the hard drive.

 

[Dougcjohn]

On SanDisk as example: Extreme - Plus - Pro, all 3 cards for video are equal. They have same constant or minimum rates and same V30 video rates. This too confuses many, and money spent when not needed.

The higher rating of Plus & Pro are max burst rate, only applies to still photography high speed cameras and their cache write. The burst rate (multiple still frames) of Mavic or similar cameras doesn't exceed even the standard Extreme card.

For video or stills, standard Extreme works great; the extra cost of Plus & Pro isn't a performance or better card for this situation. The standard Extreme Min Rate & V30 will outperform the Mavic's camera. The Plus & Pro have a little better warranty, but for the Mavic, no performance gain.

Spend the extra if desired, but it's not beneficial in these cameras.

 

[Grazuncle]

Your playing the 4k footage from the SD card? Of course it doesn't play smoothly. Download it onto the hard drive.

I have

 

[Grazuncle]

Jerky footage is almost ALWAYS due to panning, and panning too fast. Look closely at all the youtube drone videos and notice how few are using panning. But if you want it to be smooth, you gotta learn about this topic:

RED Tools | RED Digital Cinema

Convenient, multipurpose tools designed for use by filmmakers and camera operators to outline best practices in camera set-up for a variety of shooting situations. Available tools: Crop Factor, Recording Time, Flicker Free Video, Depth of Field, Panning Speed and Expusure.

www.red.com

and

RED.com

www.red.com

If you are going to use panning at all, it turns out the speed needs to be a LOT slower
than we would normally think.

Neal

Thanks for that.. As the thread developed it became apparent that it is the playback pc that can't cope..I stated earlier that my little laptop plays back very smoothly.

But thanks

 

[tribar]

Thanks for that.. As the thread developed it became apparent that it is the playback pc that can't cope..I stated earlier that my little laptop plays back very smoothly.

But thanks

Perhaps it's NOT your playback-PC but the settings in your playback-software on your playback-PC.
Are you using the same playback-software on your PC and laptop?
Check in the playback-software settings if hardware-decoding is disabled !!
See post #32 for an example for VLC media player.

 

[Grazuncle]

Perhaps it's NOT your playback-PC but the settings in your playback-software on your playback-PC.
Are you using the same playback-software on your PC and laptop?
Check in the playback-software settings if hardware-decoding is disabled !!
See post #32 for an example for VLC media player.

Yes exactly the same and different players.. I thought of getting another graphics card but it is not that simple apparently.

I think I'll stick with plain HD