Frame rate really 30?

#1

Sorry for all the questions! Is the framerate of the stitched audio file really 30 and not 29.97? The reason I’m asking, is that I’m having trouble matching other material (separate video of the scoreboard, external audio recording) to the stitched output file. I can match them perfectly to the source material, but it quickly drifts against the stitched file.

The odd thing, is that Windows reports different total time for the video files, even though I am stitching the entirety of the source material. For example the source file properties are:
source_properties
and the final stitched file is:
stitch_properties

Note the difference in the total time. There is a 5 second discrepancy in total time…

Update: I exported the audio with the stitched video, and it starts out fine, but is completely out-of-sync by mid way through the game. Maybe I’m doing something wrong? Thanks!

#2

Currently the fps can only be an integer. This is a negligence and I’ll fix in the next release.

#3

Thanks for the reply! I currently have my GoPro 10s set for 30 FPS, but I guess this ends up actually being 29.97. This means I can’t have my audio synced (via ActionStitch left/right or from external source) until the new release then, right?

I guess one work around would be to convert my video via external program to true 30 fps before loading into ActionStitch?

#4

As a test, I tried converting the my GoPro10 files to true 30fps using Handbrake. I verified that the new source files have the same duration and match up to the original (1 frame difference). After stitching, the result is better, but it still slowly loses sync with audio, enough that is distracting because the sound associated with the basketball dribbles is off.

For reference:

  • source file length: 1:14:53
  • stitch of 29.97 files: 1:14:48
  • stitch of 30 fps files: 1:14:52

Here are the 4 files lined up in a video editor for comparison:

timeline_compare_labelled
timeline_compare_labelled1361×576 63.9 KB

Maybe there is something else in addition to the integer frame rate? There still seems to be some frames being dropped even though the source frame rate was an integer 30 fps…

#5

I guess the discrepancy may be caused by how the final video was created: the big stitch job is divided into many short video segments, each of which is about a few minutes long. These segments are then combined into the final video. This is mainly for fast resuming when an error occurs during the stitching.

Can you share your original videos so I can use them for testing?