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iTunes Music Shop, AAC Codec has entered a mainstream world of music playback.
OGG
OGG format is short for OGG Vobis. It is a new audio compression format. Similar to existing
MP3 formats, OGG has a unique feature - It is totally free, open and has no patent limits. OGG
Vobis also has a specific advantage: it supports multi-channels. When it is becoming popular,
OGG can be used to code DTS multi-channels audio.
A6.3 Photo formats
JPEG
JPEG is the widest used compression image format, it is a lossy compression format.
Over-compressed files might bring negative effects: blur, sots and Mosaic. This situation is
similar to the phenomenon of image distortion discovered in DVD and VCD of low Bit Rate.
BMP
It is a name short for bitmap. This kind of files can be saved using different color-depth
(expressed by number of bit per sample image dot, with value of 1, 2, 4, 8, 16, 24). It is relative
to the color amount displayed in the images. BMP files with 24 bits (the real color) are lossless
but larger than JPEG files. Microsoft Windows GDI usually uses this format.
