Audio repair and recovery :

 

An audio file format is a container format for storing audio data on a computer system. Despite its name, there are many file formats for storing audio files.

The general approach towards storing digital audio formats is to sample the audio voltage (corresponding to a certain position in the membrane of a speaker) in regular intervals (e.g. 44,100 times per second for CD audio or 48,000 or 96,000 times per second for DVD video) and store the value with a certain resolution (e.g. 16 bits per sample in CD audio). Therefore sample rate, resolution and number of channels (e.g. 2 for stereo) are key parameters in audio file formats.

Our recovery technicians provide audio file container recovery services like :
AIFF Audio (.aif) recovery and repair
MP3 (.mp3) recovery and repair
M3U Play List File (.m3u) recovery and repair
MIDI (.mid, .midi, .rma) recovery and repair
Windows Audio (.wav) recovery and repair
Creative Voice File (.voc) recovery and repair
RIFF Multimedia File (.riff) recovery and repair
Audio Visual Research (.avr) recovery and repair
AU Audio (.au) recovery and repair
OGG Audio (.ogg) recovery and repair
Digital Speech Standart (.dss) recovery and repair

Other list of files that we may recover:

.669 UNIS Composer 669 Module Recovery and repair, .6cm Six Channel Module Recovery and repair, .8cm Eight Channel Module Recovery and repair, .8med Amiga OctaMed Music File Recovery and repair, .8svx Amiga 8-Bit Sound File Recovery and repair, .aac Advanced Audio Coding File Recovery and repair, .abc ABC Music Notation Recovery and repair, .act ADPCM Compressed Audio File Recovery and repair, .ahx WinAHX Tracker Module Recovery and repair, .aif Audio Interchange File Format Recovery and repair, .aifc Compressed Audio Interchange File Recovery and repair, .aiff Audio Interchange File Format Recovery and repair, .al A-Law Compressed Sound Format Recovery and repair, .alaw A-Law Compressed Sound Format Recovery and repair, .amr Adaptive Multi-Rate Codec Recovery and repair, .ape Monkey's Audio Lossless Audio File Recovery and repair, .au Audio File Recovery and repair, .aud Compressed Audio File Recovery and repair, .avr Audio Visual Research File Recovery and repair, .band GarageBand Project Recovery and repair, .cda CD Audio Track Recovery and repair, .cel Audition Loop Recovery and repair, .cmf Creative Music Format Recovery and repair, .cwp Cakewalk SONAR Project Recovery and repair, .d00 OPL2 FM Audio File Recovery and repair, .d01 OPL2 FM Audio File Recovery and repair, .dss Digital Speech Standard File Recovery and repair, .dvf Sony Digital Voice File Recovery and repair, .ear Eyemail Audio Recording Recovery and repair, .far Farandole Composer Module Recovery and repair, .flac Free Lossless Audio Codec Recovery and repair, .flp FruityLoops Project Recovery and repair, .ics IC Recorder Sound File Recovery and repair, .iff Interchangeable File Format Recovery and repair, .it Impulse Tracker Module Recovery and repair, .kar Karaoke MIDI File Recovery and repair, .kin Kinetic Music Project Recovery and repair, .ktp Kinetic Project Template Recovery and repair, .lso Logic Audio Project Recovery and repair, .m3u MP3 Playlist Recovery and repair, .m4a MPEG-4 Audio Layer File Recovery and repair, .m4b iTunes Audio Book Recovery and repair, .m4p Protected AAC File Recovery and repair, .med Amiga MED Sound File Recovery and repair, .mid MIDI File Recovery and repair, .midi MIDI File Recovery and repair, .mmf Synthetic Music Mobile Application Format Recovery and repair, .mod Amiga Music Module File Recovery and repair, .mp2 MPEG Layer II Compressed Audio File Recovery and repair, .mp3 MPEG Layer 3 Audio File Recovery and repair, .mpa MPEG Audio File Recovery and repair, .mpc Musepack Audio File Recovery and repair, .mpu Moving Picture Experts Group 3 Layer Audio Recovery and repair, .mp_ Mobile Phone Sound File Recovery and repair, .msv Memory Stick Voice File Recovery and repair, .mtm MultiTracker Module Recovery and repair, .nap Napster Copyright-Secured Music File Recovery and repair, .ogg Ogg Vorbis Compressed Audio File Recovery and repair, .pca Perfect Clarity Audio Recovery and repair, .pcm Pulse Code Modulation Recovery and repair, .pvc Panasonic Voice File Recovery and repair, .ra Real Audio Recovery and repair, .ram Real Audio Media Recovery and repair, .rfl Reason ReFill Sound Bank Recovery and repair, .rmf Rich Music Format Recovery and repair, .rmi RIFF MIDI (RMID) File Recovery and repair, .rmx RealJukebox Format Recovery and repair, .s3m ScreamTracker 3 Sound File Recovery and repair, .saf Secure Audio File Recovery and repair, .sd2 Sound Designer II File Recovery and repair, .sdx Sample MIDI Dump Exchange Recovery and repair, .sf Sound File Recovery and repair, .sfk Sound Forge Audio Recovery and repair, .sib Sibelius Score Recovery and repair, .smf Standard MIDI File Recovery and repair, .smp SampleVision Audio Sample Format Recovery and repair, .snd Sound Clip Recovery and repair, .sng MIDI Song File Recovery and repair, .sprg Synclavier Program File Recovery and repair, .sseq Synclavier Sequence File Recovery and repair, .ssnd Synclavier Sound File Recovery and repair, .svx 8SVX Sound File Recovery and repair, .sw Signed Word Audio File Recovery and repair, .swa ShockWave Audio Recovery and repair, .tfmx Final Music System Tracker Module Recovery and repair, .thx Amiga THX Tracker Music File Recovery and repair, .toc PSP Audio File Recovery and repair, .tsp TrueSpeech Audio File Recovery and repair, .ub Unsigned Byte Audio File Recovery and repair, .val Olympus Voice Recording Recovery and repair, .vmf Vocaltec Media File Recovery and repair, .voc Creative Labs Audio (Voice) File Recovery and repair, .voi Voyetra Voice File Recovery and repair, .vox VoxWare Audio Recovery and repair, .vrf Ventrilo Audio Recording Recovery and repair, .wav Windows WAVE Sound File Recovery and repair, .wave WAVE Sound File Recovery and repair, .wax Windows Media Audio Redirect Recovery and repair, .wma Windows Media Audio Recovery and repair, .wrk Cakewalk Music Project Recovery and repair, .xm Extended Module Audio File Recovery and repair, .xmi Compressed eXtended MIDI file

 

Types of audio formats:

It is important to distinguish between a file format and a codec. Though most audio file formats support only one audio codec, a file format may support multiple codecs, as AVI does.

There are three major groups of audio file formats:
slightly compressed formats, such as WAV, AIFF and AU.
formats with lossless compression, such as FLAC, Monkey's Audio (filename extension APE), WavPack, Shorten, TTA, Apple Lossless and lossless Windows Media Audio (WMA).
formats with lossy compression, such as MP3, Vorbis, lossy Windows Media Audio (WMA) and AAC.
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Lossy audio formats

Lossy file formats are based on psychoacoustic models that remove audio data that humans cannot or can hardly hear, e.g. a low volume sound after a big volume sound. MP3 and Vorbis are popular examples.

As of 2002, one of the most popular audio file formats was MP3, which uses the MPEG-1 audio layer 3 codec to provide acceptable lossy compression for music files. The compression is about 10:1 compared with uncompressed WAV files (in a standard compression scheme), therefore a CD with MP3 files can store about 11 hours of music, compared to 74 minutes of the standard CDDA, which uses uncompressed PCM.

There are many newer audio formats and codecs claiming to achieve improved compression and quality over MP3. Vorbis is an unpatented, free codec. Microsoft has its Windows Media Audio format and Apple the Advanced Audio Coding format. Both are closed source and proprietary.
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Lossless audio formats

Lossless audio formats (such as TTA and FLAC) provide a compression ratio of about 2:1, sometimes more. In exchange for their lower compression ratio, these codecs don't destroy any of the original data. This means that when the audio data is uncompressed for playing, the sound produced will be identical to that of the original sample. Taking the free TTA lossless audio codec as an example, one can store up to 20 audio CDs on one single DVD-R, without any loss of quality. The downside to this method is that this DVD disc will only play on a device that can both read DVDs and decode the chosen codec. This will most likely be a home computer. Although these codecs are available for free, one important aspect of choosing a lossless audio codec is hardware support. It is in the area of hardware support that FLAC is ahead of the competition. FLAC is supported by a wide variety of portable audio playback devices.

One important consideration is in the area of DRM, where FLAC is very clear about being against any copy prevention features of any kind. More importantly this means that you the owner of the computer will not be restricted in using the FLAC files.

Lossless compression of sound is not nearly as widely used outside of professional applications, as lossy compression can provide a much greater data compression ratio with nearly the same apparent quality. Usually, the difference of quality between lossless and lossy audio compression is absorbed by the quality of the hardware, such as headphones, cable connectors, or sound speakers.
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Uncompressed audio formats

There are many "uncompressed" data formats. The most popular of them is WAV, probably because it is only slightly compressed and works with Apple's Mac and the Microsoft Windows computer Operating Systems. WAV is a flexible file format designed to store more or less any combination of sampling rates or bitrates. This makes it an adequate file format for storing and archiving an original recording. A lossless compressed format would require more processing for the same time recorded, but would be more efficient in terms of space used. WAV, like any compressed format, encodes all sounds, whether they are complex sounds or absolute silence, with the same number of bits per unit of time.

Let's take an example. A file contains a minute of a symphonic orchestra playing beautifully followed by a minute of silence. If the sound were stored in WAV, the same amount of data would be used for each half. If data were encoded with TTA, the first minute would be a bit smaller than in the WAV file, and the silent half would take almost no disc space at all. But then, recording in the TTA format would require a lot more processing than the WAV.

The WAV format is based on the RIFF file format, which is similar to the IFF format.

BWF (Broadcast Wave Format) is a standard audio format created by the European Broadcasting Union as a successor to WAV. BWF allows metadata to be stored in the file. See: European Broadcasting Union: Specification of the Broadcast Wave Format - A format for audio data files in broadcasting. EBU Technical document 3285, July 1997. This format is the primary recording format used in many professional Audio Workstations used in the Television and Film industry. Stand-alone file based multi-track recorders from Sound Devices, Zaxcom, HHB USA, Fostex, and Aaton all use BWF as their preferred file format for recording multi-track audio files with SMPTE Time Code reference. This standardized Time Stamp in the Broadcast Wave File allows for easy synchronization with a separate picture element.