VRO is a digital audiovisual file format for streaming DVD recordings. When generated, this file usually comes with an IFO file for providing the location information of the VRO file. Generally, VRO is like a collection of VOB files. However, fragmented VROs are not widely supported.
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MP4 (MPEG-4 Part 14) is a video container format based on QuickTime MOV. But unlike MOV, it adds support for other MPEG features. MP4 supports video (MPEG-4 Part 2 and MPEG-4 Part 10/H.264), audio (MP3, AAC, SLS, TTSI, and ALAC), and subtitles (MPEG-4 timed text). It’s this codec combination that gives MP4 its flexibility.
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