The challenge when using multiple video clips in the same video editor timeline is how to get them into sync with each other. Most all video editors provide a tool to synchronize the video clips within the timeline based on the audio contents. That is a great time saving tool to help the video editor get the video "close" to being synced.
Why do I say close to being synced? What I've found is that each dash camera model has a slight variance in how it combines the video track and audio track into the output video file. One would assume the video and audio are always in sync with each other in any given video file and for the most part that is somewhat true. Each dash camera make/model/firmware has some amount of variance from being absolutely in sync (video & audio) on a frame-by-frame basis. Most are very close to be 100% in sync, but there can be one (1) to several frames of an offset between the video and audio depending again on the model/model/firmware of the dash camera.
There are left-to-right and windshield curvature factors that impact what shows up on the left/right edges of the video. The assumption is that the up/down alignment is as close the to same as possible as well to minimize that factor in determining what shows up in the video.
Here's an example of frame grab from an A229 Pro front camera video and an A329 front video with my vehicle being motionless. I used the Adobe Premiere Pro feature to sync the audio track contents. I've added the green lines to show where the center positions for each video content is located. There are a couple of objects that I'll point out in this comparison. The four position vertical stoplight on the left side of the video can be seen in the A229 Pro video, but that stoplight cannot be seen in the A329 video footage. There are two possible things causing that to be true and those are the fact that the A329 is mounted about 6 inches to the right of the A229 Pro front camera on the windshield and/or the A229 Pro front might have slightly wider viewing angle. The only way to be sure would be to mount them both in the same position on the windshield and compare. That's what
@Panzer Platform is doing with his test.
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You can see the audio track contents are "in sync" at this point in time.
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When I combine video footage from two or more cameras in the same video editing timeline, I use the audio sync feature to get them 99.5% in sync. I then look for visual clues to allow me to adjust the placement of the videos in the video editor timeline to make the visual content become synchronized. I look for stoplights changing, vehicle turn signal(s) turning on/off or any shadows that are cast on the vehicle's window glass to know if they're in sync already or how may frames they need to be adjusted to get the video contents in sync.
Using these same two sample videos, I found the video frame that contains the stoplight changing from red-to-green and I used that to sync the videos in the timeline. The crosshair in the A229 Pro front camera footage is somewhat to the left of the tree in the lot across the street. The same center crosshair is directly in the middle of the tree trunk. That shifting is from the left-to-right placement on the windshield. Comparing the placement of the grey car, the same shifting is present due to the camera position on the windshield, but the alignment of the grey car to the white pickup truck is more synced since the video events are in sync. The same can be said for the white minivan's placement relative to the Carl's Jr sign it's located under in the footage.
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With the video motion in sync (stoplight changing to green), you can see the audio tracks are now out of sync. The audio tracks are seven (7) frames out of sync. That's why when I have multiple video files in the same video editor timeline, I have to sync them using a two phase approach. First use the audio syncing tool in the video editor and then look for visual clues to sync the video motion events.
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