tests: add format / codec transcoding tests

This test group is intended to check the format / codec transcoding
capabilities of the library. The reference files are used to ensure
that encoding or decoding was successful.

The following formats are currently being tested:

  - amr_efr
  - gsm
  - racal_hr
  - racal_fr
  - racal_efr
  - ti_hr
  - ti_fr
  - ti_efr
  - rtp_efr
  - rtp_hr_etsi
  - rtp_hr_ietf
2 files changed