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Convert AMR to FLAC

AMR to FLAC Conversion Software converts AMR files to FLAC and keeps ID3 tag. The converter offers many useful features. For example, automatically normalizes volume of AMR and FLAC so that all output files have the same volume; skips the first X milliseconds of AMR and FLAC files when converting; only converts X milliseconds of AMR and FLAC files; joins multiple files to one file. The converter also convert files to popular formats such as VOC, MP2, AAC, M4A (MPEG-4 audio), AMR, AU, MPA, MMF, etc. It could convert OGA to M4B (MPEG-4 audiobook), WMV to AAC, MPC to M4A (MPEG-4 audio), AVI to AMR, WMV to M4R (iPhone ringtone), WM to AWB, and so on.

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

AMR to FLAC 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 FLAC?
Free Lossless Audio Codec (FLAC) is a file format for lossless audio data compression. Being lossless, FLAC does not remove information from the audio stream, as lossy compression formats such as MP3, AAC, and Vorbis do. FLAC's primary author is Josh Coalson. FLAC reduces bandwidth and storage requirements without sacrificing the integrity of the audio source. A digital audio recording (such as a CD track) encoded to FLAC can be decompressed into an identical copy of the audio data. Audio sources encoded to FLAC are typically reduced in size 40 to 50 percent (46% according to their own comparison). FLAC is suitable for everyday audio playback and archival, with support for tagging, cover art and fast seeking. FLAC's free and open source royalty-free nature makes it well-supported by many software applications, but FLAC playback support in portable audio devices and dedicated audio systems is limited at this time.