"How can I convert movies and TV shows purchased from iTunes from M4V to MP4 on Mac? Or can I even do that given they are copy protected?"
By using the FairPlay DRM decryption, the M4V movies, TV shows, and music videos purchased or rent from iTunes Store can only be played on authorized computers in iTunes. If you want to convert DRM protected M4V videos to MP4 so that you can play them on any devices, you first need a profession M4V DRM Removal. Then is there any way to crack the DRM from iTunes movies and TV shows as well as convert the DRM-ed M4V to MP4 format?
iTunes M4V Converter for Mac can remove DRM from iTunes movies and convert M4V to MP4 on macOS Sierra and Mac OS X El Capitan. This software can automatically detect M4V files on your iTunes and convert them at 30X faster speed with original audio tracks (5.1 Dolby audio), subtitles and video quality preserved. After removing DRM, you can play iTunes movies anywhere and keep iTunes rental forever without worry of expiration.
iTunes M4V Converter - The Best M4V to MP4 Converter for Mac
Use iTunes M4V Converter to remove DRM from iTunes videos and convert M4V to common MP4.Download
Part 1 Quick Way to Convert DRM-ed M4V to MP4 on Mac
After launching iTunes M4V Converter for Mac, you can click "Add files" to select iTunes movies, TV shows or music videos.
You don't need to find M4V files on iTunes library as the program can detect all iTunes videos on your Mac.
Before conversion, please make sure that you have authorized iTunes on your Mac with the same Apple ID and password you used to purchase, rent or download the iTunes video.
Choose the output audio tracks and subtitles by clicking "settings" icon. Otherwise, it will keep all the tracks and subtitles in output videos. This program not only keeps all multi-language subtitles and audio tracks but also retain the audio track (5.1 Dolby audio) as well as closed caption after conversion.
Click "Convert" button to begin to convert iTunes M4V to MP4 on Mac.
After conversion, you can find the converted MP4 files by clicking the "History" button and then copy and transfer the non-protected iTunes movies or TV shows to any portable devices.
Part 2 Additional Tips: What's M4V and How to Open an M4V File
What is M4V?
Developed by Apple and nearly identical to the MP4 format, a file with the M4V file extension is a MPEG-4 Video file, or sometimes called an iTunes Video file.
You'll most often find these types of files used for movies, TV shows, and music videos downloaded from the iTunes Store.
Apple may protect M4V files with DRM copyright protection to prevent unauthorized distribution of the video. Those files, then, can only be used on a computer that has been authorized to play it.
How to Open an M4V File?
You can play protected M4V files only if the computer is authorized to do so. This is done through iTunes by logging in to the same account that purchased the video. These DRM protected M4V files can also be played directly on the iPhone, iPad, or iPod touch that purchased the video.
M4V files that are not protected with such restrictions can be opened in VLC, QuickTime, Windows Media Player, and probably other media players. You can also use Wondershare Video Converter Ultimate for Mac to convert unprotected M4V videos to MP4, AVI, FLV, MOV, WMV, etc.
If you are an Apple Music subscriber and also want to remove DRM from Apple Music so you can keep Apple Music songs even if you cancel the subscription, you can use Apple Music Converter to bypass DRM from Apple Music and convert Apple Music M4P songs to common MP3.