Hello, I have yet to fly my I2 and have been slowly going through testing everything. I just powered it up for the first time yesterday, and today I was testing the recording of the camera and gimbal operation. I recorded some footage to the microSD card that came with the I2 at very basic settings (UHD, 29.97fps, 1/60 shutter, all of the color and profile settings at default) and took a look at it on my edit suite. The I2 was sitting on the floor stationary and I did a series of pans at different speeds (medium, slow, and creep) followed by a series of tilts at the same variety of speeds. I was expecting to see nice smooth footage, but instead what I saw was stuttered/jumpy. It gave me flashbacks of earlier DSLRs with rolling shutter issues, but that was something you normally only saw in pan movements, this you see in the tilt too (although not as noticable). I checked to make sure the gimbal was moving smoothly and after studying it closely through the full range of movement it is moving just fine, although when it pans it makes a "whine" that I don't hear when it tilts or rolls. Since the gimbal movement was not introducing any stutter or jerk, I thought the problem may be the microSD card may not be fast enough for 4K recording, even though it is "U3". So I knocked the resolution down to FHD and recorded the same pan and tilt movements again with all of the other camera settings remaining the same. When I examined the footage I saw the very same issues I had with the higher resolution UHD stuff. Here are the links to my footage on YouTube, I exported the UHD footage as FHD to help make the upload easier:
UHD Pan =
UHD Tilt =
FHD Pan =
FHD Tilt =
I really hope this is something that can be fixed, and please if anyone has similar issues or there is a DJI support person who reads this I really need help! I have used a lot of different cameras and gimbals and this is not the quality I can take onto professional shoots, so until this is sorted I am unable to use this equipment. Oh, and here is the link to a video of the gimbal making the pan "whine" I mentioned above (I had to move the camera so the mic was next to the motor to pick up the sound over the noise of the copter fan, that is why I was not able to show the gimbal as it panned):


Thanks!

Plays perfectly on You Tube, no stutter. Try it yourself!

see http://forum.dji.com/forum.php?m ... =1&extra=#pid676213 for an extensive discussion
The 'problem' disappears on YT because the video stream is transcoded and recoded.

There is some decoding issue with the current h.264 implementation on some processors.
Nothing wrong with the I2 or your SD card

All those vids have some stutters on my tablet.

I'll confirm Mike's comments on this. The footage is perfectly smooth. When performing pans like this it is extremely challenging on the "decoding" side. H264 decodes by only updating the "changes" in each frame. Because of the panning/tilting, every frame is completely unique, and so it's a stress on your processor. When playing back on youtube for me, it was mostly perfectly smooth, but occasionally the frame rate would drop to something lower than 29.97, meaning the pans would be come less smooth. If I scrubbed back over the offending area, or simply clicked pause, the processing would have a chance to catch up, and everything would go back to smooth. If you view the footage in your NLE or QT player and advance frame by frame, you'll see there are no missing frames or stuttering. This is what tells you that its a playback issue relative to your machine. Alternatively, you could convert to an editing codec like ProRes. You'll most likely find that the same footage in a less compressed codec plays back absolutely fine.

there is nothing wrong with the h264 codecs from the I2. (in camera proRes is a different matter:-) 4k h264 is challenging to playback on many machines, and thats all you are seeing here.

Oh, and about the Gimbal noise. I've communicated with a DJI Engineer about this and it is completely normal. This is just the gimbal motors doing their thing.  I do want to bring up the issue of that fluorescent lighting in your house though. You know that sh*t will kill you, right? :-)

Barry Goyette Posted at 2017-2-2 07:00
I'll confirm Mike's comments on this. The footage is perfectly smooth. When performing pans like this it is extremely challenging on the "decoding" side. H264 decodes by only updating the "changes" in each frame. Because of the panning/tilting, every frame is completely unique, and so it's a stress on your processor. When playing back on youtube for me, it was mostly perfectly smooth, but occasionally the frame rate would drop to something lower than 29.97, meaning the pans would be come less smooth. If I scrubbed back over the offending area, or simply clicked pause, the processing would have a chance to catch up, and everything would go back to smooth. If you view the footage in your NLE or QT player and advance frame by frame, you'll see there are no missing frames or stuttering. This is what tells you that its a playback issue relative to your machine. Alternatively, you could convert to an editing codec like ProRes. You'll most likely find that the same footage in a less compressed codec plays back absolutely fine.

there is nothing wrong with the h264 codecs from the I2. (in camera proRes is a different matter:-) 4k h264 is challenging to playback on many machines, and thats all you are seeing here.

Thank you to Barry and Mike for your feedback on my post. I am new to shooting footage using the H264 codec. For several years I have been commercially flying UAS that can carry a wide variety of camera packages, and the footage the clients would provide me for my own use played back fine on my equipment and edit suite. That is why I was concerned when I ran into playback issues with the H264 footage I shot, that I would hand it off to a client and they would have the same issues. Now that I know how to handle (and understand) the playback issue on my end, I have an encoding question for you for output to YouTube. I have been encoding video (shot on my I2 in H264 with default profile settings) from AME for upload according to YouTube's posted standards (MP4, H264, High Profile, etc), but playback on YouTube has stutters (mostly when there are significant camera moves, as expected) on every device I have tested it on. I have tried playing with bit-rates and keyframes with little success. Do you have any suggestions to mitigate these playback issues, either with camera settings/post processing or with export settings?