I'd like to point out that while adding oneMenu-menuAction is correct and works for the first 2, it is apparently mandatory (on Mac OS X) for a menu to have existing actions when added to the QMenuBar.Since my dynamic menu example doesn't add actions until the aboutToShow signal is emitted, my work-around is to populate the dynamic menu with 1 QAction that serves no.

Apple apps such as QuickTime Player, Photos, and Keynote work with many kinds of audio and video formats. Some apps prefer specific formats, but QuickTime movie files (.mov), most MPEG files (.mp4, .m4v, .m4a, .mp3, .mpg), some AVI and WAV files, and many other formats usually work in most apps without additional software.

Older or specialized media formats might not work in your app, because the format requires software designed to support it. If that happens, your app won't open the file or won't play back its audio or video.

How to search for an app that works with your file

You might already have an app that supports the format of your file. If you don't know which of your installed apps to try, your Mac might be able to suggest one:

1. Control-click (or right-click) the file in the Finder.
2. From the shortcut menu that opens, choose Open With. You should see a submenu listing all of the other installed apps that your Mac thinks might be able to open the file.

If none of your installed apps can open the file, search the Internet or Mac App Store for apps that can play or convert the file:

• Include the name of the media format in your search. To find the format, select the file and press Command-I to open an Info window. The format might appear after the label Kind, such as ”Kind: Matroska Video File.”
• Include the filename extension in your search. The extension is the letters shown at the end of the file's name, such as .avi,.wmv, or .mkv.

Learn more

• QuickTime Player (version 10.0 and later) in OS X Mavericks through macOS Mojave converts legacy media files that use certain older or third-party compression formats.
• Learn about incompatible media in Final Cut Pro X and iMovie.

win+mac

A lot of people now use it to add timecode / reelnames to DSLR shot video, in order to have dupe detection.
But it can used for a lot of other workflows as well.
(Eg better media management of non-timecoded sources.)
This tool will let you batch alter QT files.
Use it to alter properties, or to add TC / Reel info.
It is tested with QT files created by Nikon or Canon cameras, but will probably work on a lot more.
So with this, you can add Timecode, either Rec Run style, or Free Run style.
(In the case of Free Run style, time and date from the shooting can be used for TC / reel info.
Note for Resolve users:
In order to have Resolve seeing TC and Reelname, you need to set it up to do so!
To do this: go into the project settings. There, go to the 'Master project settings'
Scroll down to 'conform options'
then: check the 'Use Timecode embedded in the sourceclip' radio button
also: check the 'assist using Reelnames from the:' checkbox
and: check 'embedding in the source clip file' radio button
Now, the Reelname shows up in the bin.
(Perhaps not immediatly in the Media Pool, sometimes Resolve needs a restart. But TC and Reel should show up in a bin..)
Look at the images to see a screenshot on Resolve's project settings.
Main features include

• Add Timecode, 'free run' or 'rec run' style
• Add timecode based on THM files / metadata (more accurate, works with Canon created clips)
• Extract THM files if they are embedded in the QT (like a Canon 60D writes)
• Extract sound to 48 Khz BWF files (with optional speed change)
• Add custom reelname(s)
• Change Reel info
• Offset sound (to fix sync problems)
• Change display settings
• Change qualtiy settings
• Change speed settings
• Change amount of tracks (well, delete tracks..)
• Flatten movies after changing
• Export / transcode movies and alter them at the same time
• Rename files (add filedate) to create Unique names
• And it can add TC and Reel info from an Avid ALE.

The last function is a sort of 'Reverse Metacheat'
History
It is now in version 2.5.3 for both Win and Mac
Mac now has support for older operating systems.
Bugfixes if there are unknown files in a folder.
Mac has bugfixes for drag / drop.
Mac has gotten a bugfix for files bigger than 2 Gb.
Latest versions give you the option for 'File Modified Time' or 'File Created Time', if you want TC based on either one of them. This now looks at the date / time embedded in the file, rather than the file properties. So, a 'Get info' (mac) or 'File properties' might give you another time.
This way, even if a file is copied the wrong way, the original recording time is still read out.
NOTE:
IT CAN WORK DESTRUCTIVE.
This means, it can alter your original files, and it will do what you tell it to do.
If you tell it to delete all tracks, it will happily do so and you get stuck with empty files..
So if you don't know what you are doing, STAY AWAY!
There is a bug in either QT or OSX that can corrupt clips
if they live on a network drive. This is NOT a QTchange bug!
The same corruption can happen if you use FCP to change TC!
so, DO NOT work from network drives, unless you have tested it well!
NOTE!
FcpX only reads timecode if there is a Reelname present.
QTchange is now FcpX compatible, but you cannot leave the reelname empty!

Quotes:

I recently did a fashion commercial with a VERY internationally famous director. Throughout the shoot he was frustrated with the talent so on the sound track you could hear him swearing and complaining interspersed with 'yeah that's great cool' and so on. No drama - we only needed the video.. Space engineers ore mod. until the agency requested a copy of all the rushes. In a blind panic I was looking at a month of re-encoding until I remembered I had QTchange. 20 minutes later I'd removed all the audio tracks and was copying the rushes to the server in New York. Thanks Bouke - you saved me once again!
Mike Parsons, VFX Supervisor, Constellation VFX

Thanks. I love the software. I shoot with DSLRs and love being able to have an actual timecode for my clients to look at when selecting sound bites.
Ken Jones

I love this program!!!!!
Scott Sawyer
Outback Studio

Thank you for your prompt response and fantastic product!
Justin Ulrich

The new user can speed ahead through the learning curve simply viewing these tutorials in sequence. Practical pro-level high-resolution image editing and retouching have arrived on the iPad Pro (finally) with Affinity Photo and iOS 11. I had no idea they were included when I bought the app. Affinity designer free trial mac.

Your tools are great, so glad I found them.
Simon Hepworth