I’ve uploaded a few files to dropbox to help provide evidence of the stuttering I am seeing, with hopes that you can see it too, so that we can all agree that the issue exists and we can move forward with a fix action.
The files contain a short clip (02:38) of a documentary on early 1930’s animation history. I know it may not be the most exciting subject matter to watch, but I chose it because it contains a lot of panning scenes and Ken Burns effects, which provide a more effective way to positively identify the visual anomaly that I am seeing.
There are two source files of the same content. One is produced in it’s native 480p 29.97 fps, and the other is produced at 720p 60fps. See Dropbox files “Stutter Test 480p 2997” and “Stutter Test 720p 60” here:
https://www.dropbox.com/s/y42ldoabyxh1c ... 7.mp4?dl=0
https://www.dropbox.com/s/7jjd0u1ly3ybo ... p.mp4?dl=0
I used Quicktime Player X’s Screen Recording feature to record the playback of the 29.97 fps file in separate VLC and Quicktime X windows for side-by-side comparison. There is no audio during playback of the recording as it is only a video capture of the screen. Also visible on the MacOS desktop are two text documents; one containing my system specs, and another containing a list of predicted instances of the stuttering based on 16-second intervals. With the help of a timer in the upper right of the menu bar, I started the clock from the first instance of the stutter as seen in VLC’s window. After 16 seconds, another occurrence of stutter is observed, and this phenomena repeats every 16 seconds until the end of the video. You can follow along with the text document in the lower right of the desktop in the screen capture to see when the stuttering is predicted to occur, and you can compare that to the actual stutter you see during that timeframe. I tried to highlight the times in the text document as they coincided with the timer and the stutter. Comparatively, there is no stutter in Quicktime X’s window. Playback with Quicktime Player X is completely smooth from start to finish. See Dropbox file "Comparison Stutter Test 480p 2997 1” here:
https://www.dropbox.com/s/9zw7g5fhdtlgr ... 1.mov?dl=0
I repeated this same exact experiment two more times so as to show that the stutter happens in VLC once every 16 seconds no matter when the video is started. In other words, the stutter is observed at different parts of the same video window no matter how many times the file is played, and therefore proves that there is no defect with the source video file itself (there are no missing frames). See Dropbox files “Comparison Stutter Test 480p 2997 2” and “Comparison Stutter Test 480p 2997 3” here:
https://www.dropbox.com/s/k0z5nz76l1f92 ... 2.mov?dl=0
https://www.dropbox.com/s/gxaugpp31vh0q ... 3.mov?dl=0
Lastly, I recorded the screen again as above, but this time using the 720p 60fps source file. The file played back completely smooth in both VLC and Quicktime Player X. See Dropbox file “Comparison Stutter Test 720p 60” here:
https://www.dropbox.com/s/kx66jhv8l6w9g ... 0.mov?dl=0
Conclusion: VLC playback produces stutter on final video output unless the source video fps matches the display refresh rate. VLC should have the inherent ability to playback industry standard video frame rates without causing stutter or other artifacts as a basic feature of any modern day media player.