I’ve noticed when jumping between markers indicating video cuts is not working properly - I work with subframes always on, so I know when a marker is at the correct position reading “00” in the subframe box - Currently when locating to next cut (Marker) I still see a frame of video from the frame before or scene before - you can manipulate the marker itself and eventually get it to display the correct video frame - but I’m not convinced that’s the issue - I think it may be more of a video buffering/caching issue - I say this because I noticed when positioned on a maker that’s a 2-pop (video frame) and then jumping to 1st frame of picture, the 2-pop video frame remains on my screen - so that would indicate the video engine is not updating to reflect the video frame its actually on - this could be a cache file issue - or this could indicate a discrepancy between the timeline and the video timeline - The way I’ve been able to fix the issue is to 1fr nudge the timeline and resync the marker to the video cut – NOTING that this does not change the TC position value for the marker! The marker position remains the same, down to the “00” subframe - This indicates to me there is a value beyond the “80” subframes that’s in play here - or back to my observation about mis-aligned Marker and video tracks -
I use Video detection tool alot and bounce between markers indicating cuts hundreds of times a day - So it’s not practical to go and try and fix each individual marker to get it to register the correct video frame. And I’ve tried grabbing the whole lot of markers and attempting to re-sync and that does not work.
Try this: - use video detection tool - then bounce between markers and see for yourself if you’re indeed on 1st frame of the scene the marker indicates.
It’s hard to know where the issue is - I suspect the new video engine - it is an annoying bug - hopefully temporary
M2 Studio Mac - No additional video interface - Subframes would not have anything to do this - just mentioning this because it gives you more accuracy with positioning - N13 did have a similar issue using Video Detection Tool - in that it would often generate markers that ended up with a “xx:79” in the subframes – These markers would not locate properly to the Video frame positions either - This situation could be fixed by adjusting the “xx:79” subframes to"xx:00" subframes - This may be a clue to what’s happening in N14 – it would be great if someone else would confirm my observation - thx
Hey @felix I think you are right and found a bug. I can confirm that all my video cut detections at 25fps are at subframe number 26 before the actual cut.
Please add the “issue” tag to this post and. edit your title to BUG Video cut detection is several subframes early (0r something similar).
My current workaround is set snap to grid and grid to 1 frame. select all cuts and cmd-right arrow to snap to the next frame.
I just returned to look at this post and I’m glad to see someone has confirmed this bug – I just now taking a closer look at this, and if you zoom way in and look at video thumbnails on a cut in the timeline, you can clearly see that the thumbnail is about a frame out from what’s being output from the video engine - The cut detection tool seems to be in sync with the thumbnails but NOT the video output. This is easily confirmed - I’m not sure how to generate a big report - but this is a clear and visible indication of the issue. This would also make sense why moving between markers on cuts does not reflect the correct frame of video - please fix this -
I’d like to introduce another issue that may be related - but probably not. – WHY in the hell when extracting audio from a video file, N14 adds a frame (or close to it) to the beginning of the audio file – If you extract audio from Video with PT it’s dead nuts on - if you extract audio from a video in N14 it’s a frame off - later - this is super easy to confirm – It is a similar amount of time to the video issue in this thread -
This is a problem with the mp4 codec not with the video engine. PT has the same issues btw. Iirc this is caused by the data chunk at the start of the audiotrack in the video.
This is why you always ask for a separate audio mixdown in wav format when working in sound.
That is a good idea - and/or require a Ref with a 2-pop – We just did the test between PT and N14 with a common MP4 and the results were conclusive that the N14 extraction was 1 frame different then PT - N14 adding a frame of ‘something’ to the head of the file - clear as day
Great – thanks for the info - helpful - and yes I keep a close eye on sync related idiosyncrasy’s – can you address the original point of this thread? – brand new issue with N14 - thx a ton
Does this issue occur with ProRes or Mov? MP4 carries no metadata and uses virtual frames (iPB: Intra-frame, Predicted frame, and Bidirectional frame), where video frames are grouped. Instead of storing each frame individually, a key frame (I-frame) is saved along with data on changes from preceding and subsequent frames (P and B frames). Since iPB relies on frame prediction, it may cause subtle differences during cuts, particularly with frame-by-frame adjustments or subframe precision.
Does the editor provide a reference EDL along with a 2-pop WAV file? That would be more reliable for generating markers, rather than working from an MP4—and just to rule out a possible bug.
Test it with ProRes: Import the MOV into your editor and perform the same frame-by-frame or subframe edits. If the issue disappears, it’s likely due to MP4’s iPB encoding rather than a Nuendo bug.
Also try using EDL with 2-Pop: Import the EDL and associated 2-pop WAV file to generate markers. Check if the cut correctly interprets the timecode and syncs the cuts. This can help isolate whether the issue lies in the file format or the editor’s handling of it.
Not sure if you are afressintg me, but i never work with mp4 in my timeline. Always proes proxy LT or dnxhd. Never have sync issues.
However in N14 there is the issue from the makn topic with prores.
I will doublecheck tomorrow but i was sure i had this small subframe offset with prores.
