Detect Dolby Vision in an ISO file/BDMV folder?

[peterjcat]

Description of the feature or enhancement you'd like to see in HandBrake

Handbrake nightly on my M1 Mac with Video ToolBox is working unbelievably great with Dolby Vision when I make an MKV from an UHD ISO and feed that into Handbrake. I love that HB converts DV Profile 7 to Profile 8 automatically and with CQ at 70 I can't tell the difference between the original and the recode at 1/3 the size.

Now I'm trying to bypass the initial ISO -> MKV stage and convert directly from the ISO. Handbrake reads the ISO fine of course, except that it only sees the HDR10 layer, not the DV layer, and so the encodes only include the HDR10 as well. Is there something I'm doing wrong? If not, and this is an easy change it would be a great addition (for me anyway).

Thanks for all the great work.

What Operating System are you running?

macOS 14.2.1

What version of HandBrake are you running?

Nightly 20240418214634-0adabb97d-master (2024041901)

Where did you download HandBrake from?

Github

Activity Log, Crash Log or any other details

No response

[galad87]

There was some work in progress in libbluray: https://code.videolan.org/videolan/libbluray/-/merge_requests/20
but it looks like it's stalled. I don't know if we can extract the same info from the m2ts files.

[samhutchins]

AFAIK mkvtoolnix doesn't use libbluray, and I think it's able to deal with Dolby Vision in Blu Ray structures. I'm extremely unfamiliar with this kind of thing, but it may be possible to get this without waiting for an update from libbluray

[jstebbins]

mkvtoolnix does some basic minimal parsing of bluray structures itself (portions of the clpi files I believe). HandBrake leverages libbluray to extract much more information.