What should i downmix DTS to?

[Mark RL]

Hello everyone

Im about to encode my blu-ray collection, and i know the ATV2 and ATV3 dosent support DTS HD and DTS. I dont own a 5.1set yet, but I will later, so to be a litte sted forward, i will convert my movies so they play 5.1, but if i choose 6-channel discrete, will it then play 5.1 when i get a set?

I use the Apple tv3 preset, and finds it great, i have a dolby pro logic 2, audio track and then what shall i downmix the DTS to?

Thx very much

[mic j]

Hello everyone

Im about to encode my blu-ray collection, and i know the ATV2 and ATV3 dosent support DTS HD and DTS. I dont own a 5.1set yet, but I will later, so to be a litte sted forward, i will convert my movies so they play 5.1, but if i choose 6-channel discrete, will it then play 5.1 when i get a set?

I use the Apple tv3 preset, and finds it great, i have a dolby pro logic 2, audio track and then what shall i downmix the DTS to?

Thx very much

It will play 5.1 if you use 6-channel discrete. You're basically transcoding the DTS to AC3.

[Deleted User 11865]

For AppleTV compatibility, you want:

Code: Select all

track (1): AAC 2-channel (Stereo or Dolby Pro Logic II)

track (2): AC3 Passthru if the source has an AC3 track (Blu-ray discs with Dolby Digital or TrueHD audio)
           AC3 (ffmpeg), 6-channel discrete (which means 5.1) if the source has DTS or LPCM audio instead

[Mark RL]

Thanks Then I can get going

[Tree Dude]

FYI AC3 @ 640kbps (the highest HB supports for AC3 using 6-channel) is pretty much DVD quality sound. It is about a quarter the bitrate of a DTS-HD lossless track. Just something to keep in mind (I convert all my lossless audio to that to save space).

[Deleted User 11865]

Well, it's better than DVD quality (which has a limitation of 448 Kbps for AC3).

Of course there's the issue of re-encoding a lossy source (e.g. in the case of DTS, where HandBrake can only decode the core); lossless -> lossy -> lossy may negate the advantage of using higher-than-DVD bitrates.

[TedJ]

Not to mention the maturity of ffmpeg's AC3 encoder versus the commercial competition.

[Deleted User 11865]

Not to mention the maturity of ffmpeg's AC3 encoder versus the commercial competition.

Indeed. Though Justin spent a good deal of time fine-tuning his encoder, so I'm inclined to suspect that combined with the increased bitrate, and given the same source, his encoder (i.e. Libav's) at 640 Kbps should beat a commercial encoder at 448 Kbps (though I have not tested, much less ABXed, this statement).