VideoIO.jl can’t seem to open a .mkv video

General Usage
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4

I believe that is the list of supported output pixel formats, this should build an ffmpeg pipeline to transcode the pixel format to one of those (selected here).

Looking at the stack trace, this line stands out:

avio.jl:275

    bad_px_type = transcode && target_format !== nothing && !is_pixel_type_supported(target_format)

The default value for transcode is true and target_format is nothing, so leaving those unchanged should never trigger the test for is_pixel_type_supported, which is the function throwing the error. Just to be sure you are using the most recent versions, what is the output (in a new julia session) of

# press ] to enter package mode and create a temporary environment
(@v1.7) pkg> activate --temp
  Activating new project at `/tmp/jl_z2sW4n`

# with only VideoIO and it's dependencies.
(jl_z2sW4n) pkg> add VideoIO

# press <Backspace> to return to REPL mode.
julia> using VideoIO

julia> ENV["JULIA_DEBUG"] = VideoIO

julia> io = VideoIO.open(“test.mkv”)

julia> v = VideoIO.openvideo(io)