Fix bad audio metadata (issues #73)

[SteveMcFarlin]

It looks like issue #73 was never addressed. This PR has the suggested fix.

[MathieuDuponchelle]

lgtm thanks :)

[heftig]

Shouldn't this be using BPF instead of BPS?

[SteveMcFarlin]

@heftig I am not sure of the answer here. You might want to open an issue if you think BPF is the right choice.

[MathieuDuponchelle]

Why would BPF be correct here? The third parameter to gst_buffer_add_audio_meta is a number of samples no?

[heftig]

gst_buffer_add_audio_meta expects the number of samples in the buffer. The wording is a bit ambiguous, but the example given for non-interleaved layout makes it clear that the buffer size should be equal to channels * samples * sample_stride.

BPS produces the bytes per sample (the sample_stride), while BPF produces the bytes per frame (channels * sample_stride).

So in the case of a non-mono stream I'd expect the meta to still be broken.

[MathieuDuponchelle]

Please see my answer here