Hey guys,

I'm having an issue with my Mini 2 I haven't experienced before.

I recorded some 50fps footage of a storage box facility (which should have been 4k25 actually but I forgot to switch), but whenever I render it out of Premiere Pro at H264 with the same settings as input, I see this weird flicker on my footage. I've tried several different export settings and premiere pro related solutions, but I can't seem to figure it out. The 50fps shouldnt be a problem right? There's no flickering on the raw footage...

Would be great if anyone here could help me out! Here's the exported footage: https://www.youtube.com/watch?v=KN6HAl_fn6o (you can see it best here when focussing on the black parts of the building around 3-7 seconds.

Thanks in advance!
T

Hello there T. I am sorry for the trouble this has caused and thank you for reaching out. I hope that our fellow DJI Co Pilots who uses the Premiere Pro can give out the best recommendation and information with regards to this matter. Thank you.

DJI Stephen Posted at 7-23 19:38
Hello there T. I am sorry for the trouble this has caused and thank you for reaching out. I hope that our fellow DJI Co Pilots who uses the Premiere Pro can give out the best recommendation and information with regards to this matter. Thank you.

Thanks for the friendly welcome! Still haven't found a solution so hopefully someone can help me out :-)

The problem is you have duplicated every frame causing stuttering, the mini 2 does not recorded 4K. 50fps, if you rendered at 50fps you have duplicated every frame causing your issue.

DJI-Osmo-User-1 Posted at 7-24 08:43
The problem is you have duplicated every frame causing stuttering, the mini 2 does not recorded 4K. 50fps, if you rendered at 50fps you have duplicated every frame causing your issue.

Thanks for the reply! However, I didn't record or render at 4k50. I both recorded and rendered in 2.7k 50fps, which shouldn't cause any problems normally (did that before without problems).

Any other ideas? ;-)

tijndekkers Posted at 7-25 02:12
Thanks for the reply! However, I didn't record or render at 4k50. I both recorded and rendered in 2.7k 50fps, which shouldn't cause any problems normally (did that before without problems).

Any other ideas? ;-)

In addition: I don't think it's an FPS related problem, since the vid is still just as fluent as the raw file. It looks more like some sort of auto exposure is applied after rendering or so, but I have no clue how that would've happened...

It seems to be an issue related to the way you're rendering the video, not to the video itself as it was taken by the Mini 2. There are many parameters to set when encoding a video and probably one of them may be wrongly set. For instance, did you turned off the interlacing ? Video from Mini 2 are progressive and they must be rendered in that way (this is just an example). May you provide a screenshot with your encoding options ? As an alternative, you may try to encode the video using another application. For instance, HandBrake (https://handbrake.fr) is free and provides very good results. But also this application requires a good knowledge about the meaning of the encoding options.  

FabioV Posted at 7-25 02:38
It seems to be an issue related to the way you're rendering the video, not to the video itself as it was taken by the Mini 2. There are many parameters to set when encoding a video and probably one of them may be wrongly set. For instance, did you turned off the interlacing ? Video from Mini 2 are progressive and they must be rendered in that way (this is just an example). May you provide a screenshot with your encoding options ? As an alternative, you may try to encode the video using another application. For instance, HandBrake (https://handbrake.fr) is free and provides very good results. But also this application requires a good knowledge about the meaning of the encoding options.

Hi Fabio, thanks for the clear reply. I know handbrake but that doesn't give me the option to edit which makes the process unnecessary long imo (this vid is just as a sample).

Below are some screenshots of my export settings. Anything strange here maybe? :-)

A bitrate of 10 Mbit/s is quite low for a 2.7K video at 50 fps. I suggest to try 20 or 30 Mbit/s. Mini 2 videos are at 100 mbit/s.

But the strangest think is the color space selection and the Light Levels. Mini 2 videos are recorded with Rec709 color space and you're encoding to P3D65 with an high dynamic range (from 0,05 cd/m2 to 1.000 cd/m2) that are the typical HDR values. In the low contrast areas (the shadows) this can create artifacts. I suggest to set the color space to Rec709 and to reduce the dynamic range (maybe in Rec709 the default is different).

FabioV Posted at 7-25 05:19
A bitrate of 10 Mbit/s is quite low for a 2.7K video at 50 fps. I suggest to try 20 or 30 Mbit/s. Mini 2 videos are at 100 mbit/s. The flickering may be due to a low bitrate. What are the options available under Time Sampling ? Is there somethink like "Optical flow" ? That setting may improve the quality, but the encoding time will increase.

Well this is definitely where the problem is, thanks! I always assumed when I pick 'match source' it would also duplicate the bitrate, but apparently it doesn't. The more I up the bitrate on the render the less the flickering appears. Is this purely a compression issue on 50fps then?

Is there a decent way to reduce file size without introducing issues like this? I'd like the flickering fully gone but that only happens when I manually match the bitrate to the source, which makes the file even larger than the original :')

tijndekkers Posted at 7-25 05:48
Well this is definitely where the problem is, thanks! I always assumed when I pick 'match source' it would also duplicate the bitrate, but apparently it doesn't. The more I up the bitrate on the render the less the flickering appears. Is this purely a compression issue on 50fps then?

Is there a decent way to reduce file size without introducing issues like this? I'd like the flickering fully gone but that only happens when I manually match the bitrate to the source, which makes the file even larger than the original :')

Please look at the output color space. I edited my answer. Maybe setting the output colour space to Rec 709 allows you to reduce the bitrate. Another way to increase the quality with a low bitrate is using the 2 pass option.

FabioV Posted at 7-25 05:54
Please look at the output color space. I edited my answer. Maybe setting the output colour space to Rec 709 allows you to reduce the bitrate. Another way to increase the quality with a low bitrate is using the 2 pass option.

Thanks again! I can't seem to figure out how to change the color settings on export to rec709. The sequence is in that color space already, but on the export screen it stays locked on P3D65

DJI-Osmo-User-1 Posted at 7-24 08:43
The problem is you have duplicated every frame causing stuttering, the mini 2 does not recorded 4K. 50fps, if you rendered at 50fps you have duplicated every frame causing your issue.

This is only true if the original footage was at 30fps.
Because it adds frames at 'uneven' positions.
If the original footage was shot at 25fps, it won't make any difference, since it can duplicate every frame (which won't result in frame skipping or stuttering)

I think a problem could be the low bitrate, seems like compression error (but I could be wrong)