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The "arguments" value has the same behavior as the command lines arguments has – every new file in the input directory will be parsed with those arguments and the result will end up in the output directory.
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(*) MP4 proxy spec
Video: AVC Baseline@L3, 640x360px, 500kbs500kbps, source fpsFPS
Audio: AAC, 64 kbps, stereo, 48 kHz
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