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MediaRecorder does not resample Opus input audio

  • 3 replies
  • 1 has this problem
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  • Last reply by raycarino

raycarino
raycarino
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I'm on firefox 59. My microphone records audio at a sample rate of 44.1khz. Per OpusTrackEncoder https://github.com/mozilla/gecko-dev/blob/a341b32d064bafac5422f72fef6afe740045105c/dom/media/encoder/OpusTrackEncoder.cpp#L162 and this bug https://bugzilla.mozilla.org/show_bug.cgi?id=922247, I would have expected a MediaRecorder to emit ogg-opus audio at 48khz, but it's still 44.1khz after inspecting the ogg header.

Am I wrong in undrestanding that MediaRecorder should resample to 48khz if the microphone's sample rate is non-standard?

I'm on firefox 59. My microphone records audio at a sample rate of 44.1khz. Per OpusTrackEncoder https://github.com/mozilla/gecko-dev/blob/a341b32d064bafac5422f72fef6afe740045105c/dom/media/encoder/OpusTrackEncoder.cpp#L162 and this bug https://bugzilla.mozilla.org/show_bug.cgi?id=922247, I would have expected a MediaRecorder to emit ogg-opus audio at 48khz, but it's still 44.1khz after inspecting the ogg header. Am I wrong in undrestanding that MediaRecorder should resample to 48khz if the microphone's sample rate is non-standard?

All Replies (3)

raycarino
raycarino Question owner
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Forgot to mention that I'm using the MediaRecorder like so: https://developer.mozilla.org/en-US/docs/Web/API/MediaRecorder#Example

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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This topic might be beyond the expertise of this forum. There is a developer mailing list for media-related topics that might be a good place to try next:

https://lists.mozilla.org/listinfo/dev-media

raycarino
raycarino Question owner
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Thank you jscher2000!