How to Add Subtitles to MP4 Files
MP4 is an increasingly popular video format, for both its compact size and its compatibility with portable devices. Many modern video formats, like MKV or OGM, feature subtitle features that can be turned on or off. MP4 also has the capability to display subtitles, but only if they are encoded into the file, much like MKV or OGM. Those with MP4 files that are without subtitles may want to add them, and to do so requires following a specific process.
Adding Subtitles to MP4 Video
Download MP4Box and Yamb, and extract them from their zip files onto your PC. For ease of use, make sure they're in the same folder. The links for both programs are included below in the Resources section.
Run Yamb from its folder, and click on the Settings Icon. Double click on the "Advanced Settings for Yamb" entry.
Type in the file path to the MP4Box program in the Location box. For example, if it was saved directly on the C drive, it would be "C:/mp4box.exe." Then click on Next.
Click on the Creation icon from Yamb's main menu. Double click on the entry "Click to create an MP4 file."
Click on the Add button and locate the MP4 file that you wish to subtitle. Add the file to the MP4 File Creation window.
Click on the Add button again, and locate the SRT subtitle file that will be added to the video.
Change the output file's name to make a separate MP4 file, unless you wish to overwrite the original MP4 video.
Click on Next, and wait for Yamb to process the file. The time required will vary based on the video's length and file size.
When the file finishes, click "Finish" to close Yamb, or click "Back" if you have any other videos to add subtitles to.