mpeg_asc: SBR and PS hierarchical signalling

[ntrrgc]

This patch adds parsing of inner AOT and extension_sampling_frequency to SBR and PS when they're hierarchically signalled.

[wader]

Thanks! looks like no existing test covers this. Could you add a test case? there is some instructions in the dev docs how to otherwise feel free to just ask

[ntrrgc]

make test fails in my computer but I still managed to make a test and run it with go test ./format -run TestFormats/mpeg.

[wader]

Aha is it make testcli that fails? that is the expect based cli tests that are a bit flaky in some envs unfortunately, ignore them. If make testgo and CI is happy I'm happy.

CI is happy and test looks good so I'm fine merging if you feel ready?

[ntrrgc]

Indeed make testgo is happy and it's make testcli which has some problem with expect.

[wader]

Thanks!