Combining Clips Split By Camera and Matching Frame Rate

[Sparky1986]

Hi there,

I recently recorded a video of myself playing drums to a backing track. I was using the 4K 24p setting on my camera, an Olympus EM5 III. The bitrate is about 95mbps. As normal, the camera splits the video into multiple files when one file reaches 4GB, so I have 3 files in total for my ~12 minute take. I recorded audio with an external recorder and would like to use VS 2021 to sync the audio and video.

If I select all 3 video clips and the audio track to open in the Multi-Camera Editor it fails to sync correctly - I thought it would be clever enough to know the 3 video files made one take but it doesn't. If I just select the first clip and audio track, it does sync correctly. So I thought I would just combine all 3 video clips into one, and then open that one long video file in the Multi-Camera Editor and sync it with the audio track. I've noticed however, that when I try to export the video the available settings don't match the original video files. There is no 3840 x 2160 24p option, only 30p (29.97 to be exact). So first question is whether this will cause any quality issues, rendering to a higher frame rate output than the source video.

There's also no ~100mbps option, 60 is the max. Sure, when I output the final video I may want to select a lower bitrate for a smaller file for sharing/uploading. However in combining the 3 source video files to 1, I would like that to remain in the original quality but it doesn't seem like that is possible. The checkbox for exporting with the same settings as the first video clip is greyed out, most likely because VS doesn't appear to have the 24p frame rate option.

I have thought of another way I could at least sync my audio track and video clips without having to combine the 3 video clips first. I suppose I could use the Multi-Camera editor to sync the audio track and just the first video clip, then drag the multi camera project to the timeline and add the next 2 video clips immediately after the first one; the sync shouldn't be affected as the last 2 clips are a seamless continuation of the video take. But I still won't be able to export with the same frame rate as the source. I really don't know if that is much of an issue - and if I should just select 30p on my camera for future recording?

[Ken Berry]

What format is your 4K video -- .mov, mp4? When you insert the first clip into VS 2021, do you get a message asking if you want the Project Properties to match those of the video clip? (This assumes that you have ticked the box in Preferences > General > Project which says "Show message when inserting first video clip into Timeline".)

I am also not sure about bringing the multicam editor into your efforts when you have only used one camera.

For future projects, or re-doing the current one, you might want to consider changing the camera's settings to use another framerate such as 29.97/30 fps for NTSC users, or 25 fps for PAL. I would be very surprised if your camera did not allow such a change.

[tletter]

I was using the 4K 24p setting on my camera, an Olympus EM5 III. The bitrate is about 95mbps ... There is no 3840 x 2160 24p option ... also no ~100mbps option

For some strange reason you can't manually set the bitrate to more than 65Mbps, but if you enable the 'Show message when inserting first video clip into the Timeline' option then VS will match the video's properties including 24fps framerate and 99999Kbps bitrate.

VS doesn't appear to have the 24p frame rate option.

It does but the best method for matching video clip properties is explained above. You might want to consider which framerate you record at depending on how you want to display your rendered video, e.g. TV shows are typically 30 fps, whereas movies are usually shot at 24fps.

As the video is recorded with one camera, it should be straightforward to match up the audio recording with the video.

tletter
https://www.youtube.com/user/tletter

[Davidk]

I'm with Ken on this one. Having done multi-cam editing the hard way (everything in the TL/Overlay tracks, trimming and cutting to suit) and using MCE, I can assure you that it is possible to multi-camera edit using just the main UI tracks and normal methods with clips of the same scene from several cameras. But it's v tedious. MCE is better, but why use it if you only have one camera?? All MCE does is give an easy way to switch the imagery between cameras recording the same scenes from different angles. With one camera, there is only one video image at any one time so there are no other image(s) to switch between.

You can import the successive camera output files into the main TL, in sequence. Provided there is a reasonable audio 'snap' in the video+external audio recording you can sync the audio recording with the first video clip easily. Thereafter, for any video edits that shorten the time of the imagery (cuts/trims/transitions etc), make sure that the audio track is also edited in the same way, and that ripple editing is enabled, or the audio will v quickly get out of sync with the imagery.

[Sparky1986]

What format is your 4K video -- .mov, mp4? When you insert the first clip into VS 2021, do you get a message asking if you want the Project Properties to match those of the video clip? (This assumes that you have ticked the box in Preferences > General > Project which says "Show message when inserting first video clip into Timeline".)

The format from the camera is .MOV. I do have that 'Show message when inserting first video clip into Timeline' ticked in preferences but despite that I don't get the message you mentioned.

Also, when I go to the Share tab, there is a checkbox to next to a drop down with 'Same as Project Settings' and 'Same as First Video Clip' options, but the latter is greyed out. As tletter says, 24p is actually available - I have seen this now, by clicking Project Properties. I can than create my own profile and set it to 3840 x 2160 at 24p. However bitrate is still limited, to 65mbps. If I try to put in anything higher it pops up a message saying the maximum is 65mbps. I'm guessing that's why the 'Same as First Video Clip' option is greyed out.

As for why I would use the Multi-Camera Editor when there is only one camera - it's to sync the audio from an external recorder. The MCE appears to be the only way to do this automatically. Otherwise I would have to do it manually. I've played around with Cyberlink PowerDirector and you can do the automatic syncing with an external audio source directly from the timeline but I don't actually own a copy of PowerDirector currently so I'd rather use what I already have.

I was only interested in matching bitrate with the source so I could combine the 3 camera clips into 1 that would retain the original quality, then I could start the actual editing of my project using that 1 clip, beginning with the syncing of the video and external audio. I thought that if I rendered to a lower quality than the source just to combine the 3 clips to 1, then work on my project and render again to my final output, that would then be two rendering passes from the original clips, negatively affecting quality?

However I have found that, as I considered in my OP, if I just select the first of the 3 clips and the external audio file to open in the MCE it will sync them, and I can then add the final 2 clips after the first in the timeline. The only consideration here is that the MCE trimmed the 12 minute external audio file to match the 5 minutes of the first video clip. I had to drag the trim handles back to the end of the audio file to expand it back to its full length, and then drag the final 2 video clips onto the timeline after the first one.

Whilst on the topic of syncing video with external audio, for another musical performance that I'm filming, I actually have two separately recorded takes - one of me playing drums to a backing track, and another of me playing guitar to the same track. I want to sync the 2 takes and use the MCE to do picture in picture so both performances can be seen at the same time. It appears this will be more difficult than just dealing with a single take that consists of a video file and externally recorded audio. In that case the syncing is easy, but with the 2 separate takes the MCE doesn't seem to be able to automatically sync them - even though the same backing track is playing in the 2 takes, the rest of the audio content seems different enough to throw off the auto sync. That is just with the camera audio btw, not the external audio - the external audio recorder had a line out going to the camera to make syncing the audio with video for each individual take easier (i.e. making it easier for the MCE when syncing as the waveforms from the video clip and external audio recorder will be very similar and thus easy to match up - the point of doing this is to use the better quality audio capture from the external audio recorder). But that doesn't help with syncing up the 2 takes themselves. I have thought of a way to tackle this however. My external audio recorder has 6 tracks in total. When recording myself playing these instruments, I had the backing track go into the audio recorder as a stereo track, and the pickup from the recorder's mic as a stereo track so the recorder saved two stereo tracks. I can therefore adjust the levels of these two stereo tracks later, before then syncing them with the video. That gives me flexibility to say, change the volume of the backing track even though I've already recorded. I was thinking, for each of the 2 takes; guitar and drums, I could mute the recorder's mic pickup leaving just the backing track, and sync that with the video. Now I would have the 2 takes of me playing but with only the backing tracks audible. I could then sync those in the MCE, as it would find it easy to to sync with only the same backing track playing. Then I make a note of the offset between each video. Then I can go back to the audio editing, unmute the audio recorder's mic and sync that with the 2 takes respectively. Finally I could then drag those 2 takes to the timeline, and use that offset I've noted to manually sync them. However that is a very involved process, it may be better just to manually sync the 2 takes by ear.