[FFmpeg-user] Failed to open codec in avformat_find_stream_info

Ted Park kumowoon1025 at gmail.com
Wed Apr 1 11:21:47 EEST 2020

Hey there,

> Of course you are considering that possibility. No issue there. One word: AnyDVD-HD.

That is one interesting tool… So that handles decryption on the fly, and you can access the disc as a transparent UDF if I understand correctly. Looks like the maintainer is pretty diligent in keeping a database of encryption keys as well as keeping the tool’s host keys valid whenever they are “poisoned” by a user, seems unreal, I’m sure it’s worth its price tag :o

Did you make an exact copy of the disc, like to a disc image file? Or are you reading straight from the disc, with the tool in the middle? The folder/file hierarchy is one of the few things well known and relatively consistent in format, that’s how libbluray would find the playlist. Then it executes the playlist to determine which media files, and the range within the files to read.

Either way, even if the copy protection has been defeated, if you have the intact disc filesystem you will need to specify the root BDMV directory/mount point and the playlist if it isn’t auto-detected with the bluray: scheme and its parameters, so ffmpeg can use libbluray to seek in the BD specific transport streams.

You know how DVD menus, content and sub pictures/subtitles are basically one giant continuously running program implemented in special DVD “machine code” and basically run on tiny virtual machines? Well, blu-ray’s are different, but they are definitely no less complex. The “playlist” isn’t a plaintext listing but at least partially consists of machine code that drives the blu-ray “vm” complete with state machines and registers just like a DVD has. 

Essentially the .MTS or .m2ts files in a BDMV systems aren’t simple MPEG transport streams, so trying to decode them as one won’t usually work. 

Ted Park

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