Adaptive Multi-Rate Wideband
Adaptive Multi-Rate Wideband (AMR-WB) is a patented wideband speech audio coding standard developed based on Adaptive Multi-Rate encoding, using similar methodology as Algebraic Code Excited Linear Prediction (ACELP). AMR-WB provides improved speech quality due to a wider speech bandwidth of 50–7000 Hz compared to narrowband speech coders which in general are optimized for POTS wireline quality of 300–3400 Hz. AMR-WB was developed by Nokia and VoiceAge and it was first specified by 3GPP.
AMR-WB is codified as G.722.2, an ITU-T standard speech codec, formally known as Wideband coding of speech at around 16 kbit/s using Adaptive Multi-Rate Wideband (AMR-WB). G.722.2 AMR-WB is the same codec as the 3GPP AMR-WB. The corresponding 3GPP specifications are TS 26.190 for the speech codec and TS 26.194 for the Voice Activity Detector.
The AMR-WB format has the following parameters:
Extended Adaptive Multi-Rate – Wideband
Extended Adaptive Multi-Rate – Wideband (AMR-WB+) is an audio codec that extends AMR-WB. It adds support for stereo signals and higher sampling rates. Another main improvement is the use of transform coding (transform coded excitation - TCX) additionally to ACELP. This greatly improves the generic audio coding. Automatic switching between transform coding and ACELP provides both good speech and audio quality with moderate bit rates.
As AMR-WB operates at internal sampling rate 12.8 kHz, AMR-WB+ also supports various internal sampling frequencies ranges from 12.8 kHz to 38.4 kHz. AMR-WB uses 16 kHz sampling frequency with a resolution of 14 bits left justified in a 16-bit word. AMR-WB+ uses 16/24/32/48 kHz sampling frequencies with a resolution of 16 bits in a 16-bit word.
3GPP originally developed the AMR-WB+ audio codec for streaming and messaging services in Global System for Mobile communications (GSM) and Third Generation (3G) cellular systems. Its primary target applications are Packet-Switched Streaming service (PSS), Multimedia Messaging Service (MMS) and Multimedia Broadcast and Multicast Service (MBMS).
Podcasts:
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by State Radio
Omar Bay
by: State RadioDear Mr. Omar Bay,
Heard news that you left today.
You still countin' all them taxicabs, takin' you back to the time you have left?
Do you well remember Vietnam,
When you had a mother who loved her son?
Did you have to leave us all and go away?
Omar Bay, I think I'm fallin' to pieces.
Won't you help a good man get up and back on his feet?
Five winters, five winters in New York is plenty.
I'd even say it's four too many.
Won't you help a good man get up and back on his feet?
Dear Mr. Omar Bay,
I saw your old friend form the war today.
He said you went to seek God in a church or to get some warmth, whatever came first.
And now your standpipe it stands alone.
If where you place your cap is your home,
Did you have to leave us all and go away?
Omar Bay, I think I'm fallin' to pieces.
Won't you help a good man get up and back on his feet?
Five winters, five winters in New York is plenty.
I'd even say it's four too many.
Won't you help a good man get up and back on his feet?
Omar Bay, I think I'm fallin' to pieces.
Won't you help a good man get up and back on his feet?
Omar Bay, I think I'm fallin' to pieces.
Won't you help a good man get up and back on his feet?
Five winters, five winters in New York is plenty.
I'd even say it's four too many.