Newbie Question

I am new to shotcut seeking to create short informational videos for linkedin and youtube. I am needing to understand the work flow I need to implement to make this issue and routine, as I want to create 2-3 each week.

So I am recording the video and audio separately, using an H1n Zoom for sound with a lavalier mic. I am finding the synch process a bit challenging even though I do clap at the beginning of a segment. Because I am not totally comfortable in front of the camera and I am a bit of a perfectionist, and want to break the content up, I have recorded in some 4-5 segments that I need to put together.

I am envisioning doing the audio synch first, creating the 4-5 clips that have video and audio. I would like to be able to lock that clip’s audio and video together but don’t see an way to do that.

I also don’t see a clear way to handling the clip once I have synched. Do I save it as a project> Do I then have to string all the projects on the timeline?

Hi Stanley, and welcome to the forum.

Let me address the second part of your question in this reply. There are two ways to “lock together” the synchronized video and audio. One is to export the now-synchronized clips as a new video file. The upside is that this makes it easy to handle the resulting synchronized media - it’s just one file. The downside is that, unless you use a “lossless” format (which will produce ginormous files), every time you send audio and video through an encoding process, you are going to lose some quality. Will doing this once be enough to matter? Maybe not … but do it three or four or a dozen times, and the accumulated error will be very noticeable.

The second way to accomplish this “locking together” is simply to save your project; it saves as a “.mlt” file, which does not actually encode anything, but rather has the instructions needed to do the encoding. But here is the really cool thing: you can now start a new project and pull in the .mlt file just like it is a regular video. Depending on the version of Shotcut and your hardware, you may notice an initial slowdown; one on version of Shotcut, this process routinely produced an immediate crash the first time or two, but then worked flawlessly thereafter - very strange, slightly annoying, but ultimately no big deal. Here is the payoff: the .mlt file will act like a single unified video, “locked together” as you want, BUT it has not actually gone through an encoding / decoding step, so no quality has been lost. Now you can cut and splice and filter and edit this “MLT Clip” to your heart’s desire, and then export the final result.

Please make sure this has the same Video Mode as the project containing it.

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Here is a reply to the first part of your question - I decided it might be less confusing to do this in two posts rather than in one.

Synchronizing audio and video can be a bit hit-and-miss - I have gotten much better and faster with practice, but it still may require several tries to get it just right.

One thing I find helpful when recording with a separate mic is to make sure my video camera also records the audio. Even though the audio from the video camera may not be great quality, I can show the audio waveform with the video, as well as the separate audio track under that; that makes it much easier to visually match the spike from the clap. Note that you can mute the audio portion of the video track, so that it does not actually play or export - you just want it there to help synchronize.

But the above approach does run into a snag, because it presupposes that you are synchronizing audio and video by moving it on the timeline. That will work pretty well up to a point, but keep in mind that audio bit rate and video frame rate are two different things. In other words, you may not be able to line up the spike in the audio with the exact frame in the video, because the video frame rate is relatively coarse - at 50fps, for example, each frame occupies 20ms. Fortunately, you can adjust the audio track down to the millisecond. Click on the audio track and click on properties; here you will see a “Sync” setting which can be adjusted up or down.

So my work flow is to get the synch roughly close, then zoom in so that I can see track-by-track and move the audio to where the clap spikes line up as closely as possible. If needed, I then tweak it with the Sync setting.

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Oh, yeah - I left out that important bit!

Really appreciate the advice and the obvious time and care you paid to my inquiry. I feel much better about being able to handle this project now!

Thank you for your response.

I’m glad that it was helpful! This is a great community that has helped me out tremendously, so I’m happy to pay it forward.

Just so I am clear: if I have 7 sets of video and audio, I would create 7 projects of synched audio and video files. Then my final product would be to bring all 7 projects to the timeline for a final project that contains all 7 projects?

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Hi Stanley,

Sorry for the delay in responding - I’ve just gotten back from some travel.

What you propose seems to me to be the simplest & easiest way to do it, but of course, others may have other / better ideas! I’ll unpack this a bit more below, but let me briefly mention one other alternative: You could create a single .mlt file with all of the video and audio, syncing up each as needed. Then you would pull that single .mlt file in as a source, and drop the desired pieces of it (set the in and out points for each use of the file) into the timeline as needed. Would there be any advantage to doing it this way? Someone might find it easier to have a single “synced” file to work with rather than multiple files … personally I would find this less convenient, but I mention it “just in case.”

More thoughts on using 7 different .mlt files: To make this work really well, I would suggest giving some advance thought to how you are going to set up a file structure that will help to organize everything. To be honest, this is a place where Shotcut is a bit weak; it doesn’t really have much in the way of project / file management.

When you open up Shotcut, it asks you to choose an existing project or to set up a new project. For the latter, it assumes that you want to create a new directory with that project name, and then put a .mlt file with that project name in that directory. Not an unreasonable default action … but not always what you want. Say for example that you want to create 7 .mlt files in a directory called “Synced Clips,” with each .mlt file having a particular name, maybe something generic such as “Sync1.mlt” and “Sync2.mlt” and so on, or maybe something descriptive such as “Waterfall.mlt” and “Rainbow.mlt” and so on. The initial-screen project system does not lend itself to this scenario.

BUT - though it was not entirely obvious to me as a new user, it turns out that you don’t actually have to use the initial project screen. You can simply start pulling in files to the playlist or timeline, and you can “Save as” using any directory and name that you want. You can open an existing project (using the initial project screen, or just by using File:Open), modify it, and Save As to put it in a different directory or under a different name.

BUT - here’s a bit of a catch I have run into. More than once I have assembled files for a project, and they have gotten all jumbled up in a directory. I have decided that it would help to structure the files into subdirectories to make it easier to find things. I want a subdirectory called “Raw” to store all of the raw / unsynchronized clips; a subdirectory called “Synced” to store the synchronized .mlt files; and a subdirectory called “Final” to store the final .mlt file and export(s). But Shotcut does not really have a project management capability; the only thing you can do within Shotcut is a bunch of “File:Save As” operations … which is going to result in multiple left-over files in one directory after I save-as the files to a different directory.

Of course, I can easily create directories and move files around using my OS. But if I do that, the next time I open the project(s) in Shotcut, it can’t find the various source files, because they are no longer in the same place they were before. There is a fairly basic mechanism that attempts to help you find the missing files; it requires opening each project and going through to find the new directories for the different files, then saving the result. It works reasonably well, and it is not the most onerous thing to have to do … but it will save time and energy if you plan out the file structure BEFORE you start creating .mlt files, rather than after.

You can use this technique to merge multiple projects

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