3G2 is a digital multimedia container format developed by the Third Generation Partnership Project (3GPP). It can save both video and audio tracks, just like its sister format, 3GP. However, it’s the updated version of the former because it is designed for CDMA (Code Division Multiple Access) mobile phones, whereas 3GP is intended for GSM phones.
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HEVC MKV is a digital media format that uses HEVC codec, instead of the usual H.264, which is used on typical MKV files. HEVC MKV files are encoded at lower bitrates than H.264 MKV, making them smaller by up to 50%. However, software and hardware support for HEVC MKV files is quite limited as opposed to H.264 MKV, which ranks among the most popular media formats today.
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