The .ogg file format is a type of audio file that makes use of open source Ogg Vorbis compression. It is supported by devices such as Archos and Samsung but is not supported by Apple iOS devices. The .ogg format has been utilised for the provision of streaming audio. The file format is unlikely at present to take a dominant share of the digital music market due to the synonymous nature of MP3 with digital audio.
The .ogg format is actually a container that potentially allows for different streams of audio, video and metadata. Ogg Vorbis is the compression format. It provides medium to high quality audio at between 16 and 128 kbps/channel and is better quality sound than mp3. The OGG file type is a lossy codec which means that data is discarded as part of the compression technique, resulting in a smaller file size. Ogg files are optimised for music files, but will still be of acceptable quality for speech only files.
Associated programs
Apple QuickTime Player Real Player Windows Media Player
AAC is similar to MP3. It essentially cuts out, or compresses, information that the human ear cannot pick up thereby making digital files smaller and more easily managed and therefore quicker to download. AAC is about half the size of MP3 but with better quality. It is at least one tenth the size of CD digital data. Apple are the biggest users of this format and if you have an iPod or iPhone then you will have come across this format as it is iTunes default audio format.
AAC is similar in concept to MP3 but goes further. It too compresses digital audio files but to a bigger degree. It is also part of the MPEG-4 standard, it is most widely used to create small digital audio files. The current variant is specified in ISO/IEC standard 14496-3. Like MP3, AAC is a lossy algorithm. The human hearing system cannot hear quiet sounds in the presence of loud sounds of a similar frequency; for example, a voice conversation cannot be heard while an aeroplane flies low overhead. This is known as auditory masking, this allows the discarding of data with minimal loss of quality.
Associated programs
KMPlayer RealPlayer VideoLAN VLC Media Player Windows Media Player iTunes
Developed by
A combination of Fraunhofer IIS, AT&T Bell Laboratories, Dolby and Sony Corporation
