FLV (Flash Video) is a video container format developed by Adobe Systems and comes with a .flv filename format. FLV is primarily used to stream audio, video, and text data such as subtitles on sites like YouTube, Metacafe, and more. It supports MPEG-4 Part 10 (H.264) video codec and AAC sound.
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DV (Digital Video) is a file created using a digital format and saved as raw data. A DV file contains 80-byte DIFs (Digital Interface Blocks), with each block having video, audio, and metadata. DVD files use lossy compression for videos, while sounds stay uncompressed. And although it was originally meant for tape recording, DV can also save data on hard disc drives and optical discs.
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