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Convert MMF to AMR
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Total Audio MP3 Converter converts MMF files to AMR format.
The software is an all in one audio converter that supports more than 90 audio
and video files as input, and converts to popular formats such as MP3, WAV, AAC,
M4A, OGG, WMA, and AMR.
Total Audio MP3 Converter also supports batch conversion, and is full compatible
with Vista and Windows
7.
- Free Download
Total Audio MP3 Converter here and then install the software
by instructions
- Launch Total Audio MP3 Converter
- Choose MMF Files
Click "Add Files" to choose MMF files and then add them to conversion
list.
Choose one or more MMF files you want to convert and then click Open.
- Choose "to AMR"
- Convert MMF to AMR
Click button "Convert" to convert all MMF files to AMR format.
The software is converting MMF files to AMR format.
- Play & Browse
When conversion completes, you could right-click converted item and choose "Play
Destination" to play the destination file; or choose "Browse Destination
Folder" to open Windows Explorer to browse the destination file.
Top
What is MMF?
This is a music data format specified by Yamaha for portable electronic devices,
such as cell phones and PDAs. The file extension for SMAF is .MMF and is common
as ringtones for mobile phones with one of five sound chips.
SMAF resembles MIDI, but also supports graphics and PCM sound playback. Its
MIDI playback is produced via FM synthesis or PCM wavetable synthesis, where instrument
data (parameters and/or PCM samples) is stored within the .MMF file itself, similar
to module files. This enables users to create custom instruments, which will sound
exactly the same on devices with the same chip.
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)
Convert MMF to AMR Related Topics:
MPGA to AMR,
ASF to AMR,
QCP to AMR,
RPL to AMR,
DIF to AMR,
M1A to AMR,
AC3 to AMR,
FLAC to AMR,
F4A to AMR,
AMR to AWB,
SPX to AMR,
AAC to AMR,
3GPP to AMR,
DIVX to AMR,
OMA to AMR,
MP1 to AMR,
MP2 to AMR,
WMA to AMR,
NSA to AMR,
AIFF to AMR,
MOD to AMR,
WAV to AMR,
GSM to AMR,
S3M to AMR,
ROQ to AMR,
AMR to AAC,
M2TS to AMR,
VCD to AMR,
AMR to M4B,
WV to AMR,
DTS to AMR,
OGG to AMR,
AMR to OGG,
AU to AMR,
VFW to AMR,
3GP to AMR,
MKV to AMR,
GXF to AMR,
XA to AMR,
EVO to AMR
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