File Extension OGG

File extension OGG is used by multimedia files utilizing OGG container format. This format was developed by xiph.org foundation as free open-source initiative for storing audio and video streams. While OGG files may contain both audio and video data ecnoded with different codecs xipf.org foundation in 2007 requested that file extension OGG be only used for audio files with Vorbis compression. This is done for compatibility purposes.

It was proposed to the the following extensions from 2007 and on:

• file extension OGA for audio files regardless of the codec used;
• file extension OGV for video files;
• file extension OGX for applications;

OGG container format is open-ended so additional codecs can be added to it at any time. Most commonly used audio codecs currenty are:

• FLAC - high quiality losless compression of HiFi audio streams;
• Vorbis - medium and high quality compression of music;
• Speex - for low-quality lossy compression of voice data;

OGG supports Dirac, OggUVS, Tarkin and Theora video codecs that allow various quality and bitrate settings. There also several codecs for encoding subtitle information including CMML and Annodex.