I am a first-time user. I am upscaling 640 x 480 30 FPS videos using the ‘Upscale to 4K’ pre-built profile. The processed videos look fine in the preview, but the exported H264 (mp4) videos all render with a ‘stutter’ near the beginning (i.e. in the first 800-900ms or so of footage). The balance of the exported video appears to be fine. This is happening 100% of the time.
I’ve attached my system profile as per posting guidelines. I can supply a sample source video if required.
I’ve had this happen when trying to just “copy” the audio from the original to the upscaled export, especially when the the export is clipped from a longer video.
Maybe try a couple of short test exports without audio and with converted audio to see what happens.
Thanks for the fast response. You were correct! Changing the audio mode to ‘None’ resulted in exported videos with no stuttering near the start. I tested this with a sample of 6 videos and they were all perfectly exported (albeit with no audio).
I tried again with the ‘Copy’ Audio mode but receive this error on export:
*Error: Audio stream #1 contains ‘pcm_u8’ audio which can’t be used with the ‘.mp4’ container. *
Select an alternate Container to copy audio, or change Audio Mode to ‘Convert’ (this may cause a loss in audio quality).
It seems that selecting the ‘Convert’ option is the cause of the stutter near the start of the exported videos.
I guess the question is now, what can I do about this? Are there some other settings I need to tweak? Something else?
You could try mov or mkv container. Copying the audio would probably work with one of them (mp4 container is more limited with the formats it accepts).
Thank you very much - you solved my problem! I ended up exporting to a MOV container (the originals were MOV and are handled fine by Apple TV, my PC, Lightroom on the PC and Lightroom on the iPhone) with the ‘Copy’ audio option. No more video stutters.
