To convert audio, follow these steps:
- Use the "Local file" or "Online file" buttons to specify how to upload the audio to the server. Use the "local file" if you need to convert a file from your computer, in order to specify a file on the Internet, select "Online file" and in the appeared field paste the link to the file. We do not set any limits on the size of the audio file, but the larger the file, the more time it will take to convert. Just be patient and everything will turn out. You can convert files from audio or video formats. For formats that support tags, the data will also be transferred.
- To start the conversion, click the "Convert" button to start the transformation. If the conversion is successful, the file will be available in the "Conversion Results" section. If you just need to download a file, click on the file name. If you want to get other ways to save, then click on the icon to generate a QR code to upload the result to your mobile phone or tablet, and also if you want to save the file in one of the online storage services such as Google Drive or Dropbox.
Please be patient in the conversion process.
Compare AMR with OPUS
| Format introduction | The Adaptive Multi-Rate (AMR or AMR-NB or GSM-AMR) audio codec is an audio compression format optimized for speech coding. AMR was adopted as the standard speech codec by 3GPP in October 1999 and is now widely used in GSM and UMTS. | Opus is a lossy audio coding format developed by Xiph and standardized by the IETF, designed to efficiently code speech and general audio in a single format, while remaining low-latency enough for real-time interactive communication and low-complexity enough for low end ARM3 processors. |
| Technical details | AMR speech codec consists of a multi-rate narrowband speech codec that encodes narrowband (200-3400 Hz) signals at variable bit rates ranging from 4.75 to 12.2 kbit/s with toll quality speech starting at 7.4 kbit/s. Sampling frequency 8 kHz/13-bit (160 samples for 20 ms frames), filtered to 200-3400 Hz. | Opus supports constant and variable bitrate encoding from 6 kbit/s to 510 kbit/s, frame sizes from 2.5 ms to 60 ms, and five sampling rates from 8 kHz (with 4 kHz bandwidth) to 48 kHz (with 20 kHz bandwidth, the human hearing range). An Opus stream can support up to 255 audio channels, and it allows channel coupling between channels in groups of two using mid-side coding. |
| File extension | .amr, .3ga | .opus |
| MIME | audio/amr | audio/opus |
| Developed by | 3GPP | IETF codec working group |
| Type of format | Audio compression format | Audio |
| Associated programs | Audacity, FFmpeg, MPlayer, QuickTime, VLC media player | FFmpeg, AIMP, Amarok, cmus, foobar2000, Mpxplay, MusicBee, SMplayer, VLC media player, Winamp |
| Wiki | https://en.wikipedia.org/wiki/Adaptive_Multi-Rate_audio_codec | https://en.wikipedia.org/wiki/Opus_(audio_format) |