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Convert AMR to M4R

AMR to M4R Conversion Software converts AMR files to M4R iPhone Ringtone and keeps ID3 tag. The M4R is ringtone file used by iPhone. With the AMR to M4R Conversion Software, you could create your own ringtone for your iPhone. You can also convert a part of source AMR to M4R ringtone. The converter is a professional audio conversion software that also supports common format such as AAC, AU, MKA, AAC for iPod/iPhone/iPad/iTunes/DSi, MMF, MP2, OGG, AWB, etc. It could convert WMV to AAC, APE to MPA, GSM to AU, AMR to OGG, AWB to MMF, EVO to VOC, and so on.

The software supports batch conversion. It is full compatible with both 32-bit and 64-bit editions Windows 10/8/7/Vista/XP/2000.

AMR to M4R Conversion Software is compatible with Windows 10/8/7/Vista/XP/2008/2003/2000

What is AMR?
Adaptive Multi-Rate (AMR) is an audio data compression scheme optimized for speech coding. AMR was adopted as the standard speech codec by 3GPP in October 1998 and is now widely used in GSM and UMTS. It uses link adaptation to select from one of eight different bit rates based on link conditions. AMR is also a file format for storing spoken audio using the AMR codec. Many modern mobile telephone handsets will allow you to store short recordings in the AMR format. There also exists another storage format for AMR that is suitable for applications with more advanced demands on the storage format, like random access or synchronization with video. This format is the 3GPP-specified 3GP container format based on ISO base media file format.

Key Features:

Sampling frequency 8 kHz/13-bit (160 samples for 20 ms frames), filtered to 200-3400 Hz.
The AMR codec uses eight source codecs with bit-rates of 12.2, 10.2, 7.95, 7.40, 6.70, 5.90, 5.15 and 4.75 kbit/s.
Generates frame length of 95, 103, 118, 134, 148, 159, 204, or 244 bits for bit rates 4.75, 5.15, 5.90, 6.70, 7.40, 7.95, 10.2, or 12.2 kbit/s, respectively
AMR utilizes Discontinuous Transmission (DTX), with Voice Activity Detection (VAD) and Comfort Noise Generation (CNG) to reduce bandwidth usage during silence periods
Algorithmic delay is 20 ms per frame. For bit-rates of 12.2, there is no 'algorithm' look-ahead delay. For other rates, look-ahead delay is 5 ms. Note that there is 5 ms 'dummy' look-ahead delay, to allow seamless frame-wise mode switching with the rest of rates.
AMR is a hybrid speech coder which uses Algebraic Code Excited Linear Prediction (ACELP)
The complexity of the algorithm is rated at 5, using a relative scale where G.711 is 1 and G.729a is 15.
PSQM testing under ideal conditions yields Mean Opinion Scores of 4.14 for AMR (12.2 kbit/s), compared to 4.45 for G.711 (u-law)
PSQM testing under network stress yields Mean Opinion Scores of 3.79 for AMR (12.2 kbit/s), compared to 4.13 for G.711 (u-law)

What is M4R?
M4R is the standard file format for Apple iPhone ringtones. The M4R is encoded with Advanced Audio Coding (AAC). The AAC is a standardized, lossy compression and encoding scheme for digital audio. AAC has been standardized by ISO and IEC, as part of the MPEG-2 and MPEG-4 specifications.