QuickTime MP4 Playback Problems in High Sierra
"I am using a Macbook Pro 13" (early 2015) and I recently updated my macOS to High Sierra over a week ago, and then I had problems with my MP4 videos using Quicktime. It takes quicktime a long time to open. I get the bar and it stops halfway through loading and just sits there."
More than one guys have the similar issue when playing MP4 in QuickTime on macOS High Sierra. Actually, we've worked out 4 solutions to fix the problem. See details below.
Solution 1. Install QuickTime 7 Pro
QuickTime 7 and above can handle MP4 files well. QT 7 Pro is powerful enough to deal with that, but at a certain cost - $29.99.
Solution 2. Install QuickTime MP4 codec pack
You can go to Softonic or CENT to get QuickTime MP4 codec pack to strengthen your QuickTime player.
Solution 3. Find an alternative player to QuickTime
It is risky to download a codec pack that may bring adware/malware/virus to your computer. Here you can try find QuickTime player alternative to play MP4 files with ease.
A simple and open source cross-platform best media player for Mac to playback various type of video file. You can also use it to play DVDs, CDs, VCDs, and various streaming protocols. No codec packs are needed and it's completely free. You can open double windows if you want to actually view the playlist. See how to play MP4 in VLC.
MPlayer OSX Extended is one of the fastest choices on OSX to play back HD H264 videos. It also supports instant playback of MKV files and advanced styled subtitles in the ASS format. If you have an older dual core mac, which is struggling with HD video playback, give Mplayer OSX Extended a try.
Solution 4. Convert unsupported MP4 to QuickTime format
QuickTime can play most of MP4 videos with MPEG-4, MPEG-2, H.264 video codec and MP3, AAC codec. However, in some cases, you still probably come across the error message like "the movie could not be opened" when you try to open a MP4 file on QuickTime player with incompatible video codec. In order to solve MP4 won't play in QuickTime on macOS High Sierra issue, an ultimate solution is to convert QuickTime unplayable MP4 to QuickTime supported format.
To complete the conversion, you can download Brorsoft Video Converter for Mac. This Mac video converter is fully compatible with macOS High Sierra, Sierra, El Capitan, etc that has enhanced compatibility with MP4 files encoded with various video and audio codec including H.264, H.265, Photo-JPEG, AAC. It allows you batch load multiple files into the program and output QuickTime player best compatible MOV format with H.264 video codec and AAC audio coedc. What's more, proper video and audio file formats and codec won't ensure a successful video playback result, so you should also play attention to other parameters such as video resolution, frame rate, bitrate, etc. Brorsoft video converter for Mac supports parameters settings at your will.
Convert MP4 for Playing with QuickTime Player on macOS High Sierra
Step 1: Load MP4 files
Launch the Mac video converter on your computer. Click Add menu and import source MP4 video files into the program.
Step 2: Specify output file format
Click Format bar, from its drop-down list, chose QuickTime best compatible "Common Video -> MOV - QuickTime (*.mov)" as the output profile format.
Tip: Before conversion, this Mac MP4 converter software allows you to click "Settings" button right besides "Format" and enter "Profile Settings" panel to adjust video size, bit rate, frame rate, sample rate and audio channels.
Step 3: Start the conversion process
After all the setting is completed, hit right-bottom Convert button to begin the conversion from MP4 to QuickTime player supported format.
When the conversion is finished, click Open icon on the main interface to open the folder with generated files. Then you can play MP4 with QuickTime player on macOS High Sierra without hassle.