Overcoming 10-bit: mkv to m4v revisited
January 20, 2012
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Over at SoftFalcon, I mentioned that Handbreak is a powerful utility for converting videos in the .mkv container to a format more friendly for Apple handheld devices like the iPad and iPod Touch.
The main caveat about .mkv files are that subtitles are typically soft-coded in, meaning they aren’t part of the video itself. Thus, normal conversions will not retain the subtitles. Fortunately, Handbrake provides a remarkably simple mechanism that allows for subtitles in an .mkv file to be retained.
- First, load the .mkv you wish to convert.
- Then, choose the preset you wish to use. For instance, if you wish to convert for iPad, then choose the iPad preset.
- Choose a directory for the output file.
- Under the “subtitles” tab, hit the drop-down menu and select “English (SSA)”. Ensure the “burned in” option is checked, and click “Add”.
- Convert the video as per usual.
Contrasting my previous post involving a two-step process, this one is simpler and more efficient. I believe Handbrake was updated to provide superior subtitle encryption, making this the recommended method.
Of late, however, fan-subbing groups have begun releasing anime in the new 10-bit format, which provides superior quality while reducing file size. The 10-bit format sounds good in practise, but there is one main caveat: most existing players and converters can only handle 8-bit files, which are the standard. There exist ways of playing these 10-bit files on existing players, but unfortunately, fan-subbers are surprisingly uncooperative with respect to providing proper instructions as to getting 10-bit .mkv files to work. Downloading a new codec pack or using Media Player Classic is the easiest solution, but for those wishing to convert them, Handbrake only provides limited success (that is, the video quality is horrible, and the audio may become de-synchronised).
So…the question is…how does one overcome this hurdle? There exists a relatively simple solution in the form of a Handbrake Nightly SVN build. These builds use experimental techniques to process a 10-bit .mkv and generate an iOS compatible .m4v file. There are a few risks associated with using a build outside the stable release, but depending on one’s goals, the Nightly SVN build is successful at what it does and produces high-quality .m4v files. Installation of a nightly build is exactly the same as installing a stable build: just be certain to choose the one associated with your system architecture, and you will be en route to enjoying 10-bit .mkv anime on your iOS device!