3GP is a digital media container format developed by the Third Generation Partnership Project (3GPP). It stores both audio and video streams that are transmitted via 4G, 3G, and 2G mobiles phones. Here, the video format is saved in H.264/H.253 codec, while audio is streamed in AAC-LC, HE-AAC v1, AMR-NB, AMR-WB, AMR-WB+, or Enhanced aacPlus.
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AC3 is an audio format designed by Dolby Digital to offer surround sound listening. This format is available on most Blu-ray and DVD media files and is played using a Dolby Digital DVD Player. Interestingly, AC3 can be output in up to six speakers of a home stereo system. On a computer, AC3 can be opened on VLC Media Player, Apple QuickTime Player, and Windows Media Player.
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