MPA is an audio file that closely resembles thte audio-only formats like MP2. This audio format is small in size but with minimal quality loss. Technically, MPA files use MPEG-2 compression, which is known to offer small file size with original sound quality. MPA can be opened on most OS platforms and come with a .mpa filename extension.
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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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