DTS-HD Master Audio, or DTS-HD MA in abbreviation, is a lossless audio codec defined by Digital Theater System, to upscale the old DTS audio, so that it can allow a bit-to-bit representation of the original movie’s studio master soundtrack. You might have a vague idea on what the term lossless really refers to. Opposite to the term lossy, lossless is a compression method which enables you to have the exact original data from the compressed data even after extraction.
To give you a direct impression, MP3, now a ubiquitously used audio format in music industry, is a lossy audio format, while FLAC, started in 2000 by Josh Coalson, means free lossless audio codec, which allows digital audio to be losslessly compressed so that file size is reduced but without any other information being lost.
Because of its popularity, DTS-HD Master Audio now are being used on most Blu-ray discs, and is becoming the industry standard, competing with Dolby TrueHD Audio, another advanced lossless multi-channel audio codec developed by Dolby Laboratories.
How does DTS-HD Master Audio work? In a layman’s term, as you may come across in the DTS-HD white paper, the encoding process of a DTS-HD audio track is like this: first the core, a lossy format similar to DTS. Then the core will be compared to the original audio, during this period, the missing parts are added as an extra “residual” stream. Then in the end, both streams are used to create the final DTS-HD MA track. If your audio equipment is not advanced enough, which just has older decoders supporting DTS only, you’ll be limited to listen to the core stream, but if your audio system is up to date, supporting DTS-HD, you are able to enjoy both streams being played simultaneously, giving you the lossless sound effect.
However, here is the secret: even you have a DTS-HD sound system, unless you turn up the volume to a certain level while watching movies, you cannot tell the difference between the lossless DTS-HD and just the core, especially to the action movies. So, if you are one of those audiophiles, just make the best out of your advanced sound system. To normal users who do not have a special demand on sound effect, you can just stay with the core, because, as DTS-HD whitepaper states, the core itself is also a very capable lossy format and given the huge bit rate of 1500kbps that it usually uses, in most cases you are fine just ripping the core.
Next, let’s see how DVDFab can deal with DTS-HD Master Audio. DVDFab 9 has various solutions when confronted with DTS-HD Master Audio, in Blu-ray Copy or Blu-ray Ripper product. You may go through the following cases to check which situation fits yours best.
Case 1: Blu-ray Copy, Remove HD Audio
Applicable to circumstances when you want to save space on your HDD while outputting as ISO files and Blu-ray movie folders, or back up a 50GB disc onto a blank BD 25/BD 9/ BD 5 disc, or your home sound equipment simply does not support DTS-HD Master Audio. The process will produce a backup, downgrading and converting DTS-HD Master Audio to DTS/5.1 audio.
Case 2: Blu-ray Copy, Remove HD Audio and, Convert DTS to AC3
Similar to Case 1 as far as situation is concerned, the only difference is that the process will convert DTS HD Master Audio further into Dolby Digital AC 3/5.1 audio, producing a backup in much smaller file size.
Case 3: Blu-ray Copy, Keep HD Audio
In contrast to Case 1 and 2, customers who prefer this solution usually do not mind about their free space on HDD, as they may have NAS and external HDDs, or have tons of blank BD 50 discs at hand. And most importantly maybe, their home theater systems are super advanced and they are really into it to enjoy the stunning sound effect that DTS HD Master Audio brings to the table. This process will produce a backup with exact the same DTS HD Master Audio on the Blu-ray disc.
Case 4: Blu-ray Ripper, Keep HD Audio
Applicable to the situations when you want to rip the Blu-ray movie into other video files in different formats, such as M2TS, AVI, MKV and MP4 files, and when no blank BD disc is concerned, and in the meantime, the device on which you will play the resulting video is DTS HD Master Audio capable. DVDFab offers two slightly different solutions to meet your demand. One is to choose profiles with “audiocopy”, meaning to copy the audio the same as it is on the original disc, to name a few, “m2ts.audiocopy.high”, “mkv.h264.audiocopy”, and “mp4.h264.audiocopy”, which will create lossless audios but lossy videos, the other is to choose profiles with “passthrough”, such as “m2ts.passthrough”, “mkv.passthrough” and “mp4.passthrough”, which create both lossless videos and lossless audios as they are on the original Blu-ray disc. The latter equals with the term “remux”.
Case 5: Blu-ray Ripper, Remove HD Audio
Contrary to Case 4, in Case 5, you have more than one choice to downscale and convert the DTS HD Master Audio into AC3, AAC, or MP3 audio, so that you can play the converted videos on most mobile devices that are not HD audio capable. In these situations, just select normal profiles without “audiocopy” or “passthrough” from DVDFab built-in Profile Library.
Note: DVDFab 9 not only offers solutions to DTS HD Master Audio, the above mentioned cases also work on its competitor Dolby TrueHD Audio.