The error is caused by the software's install path containing a space (D:/dubb app). pyVideoTrans and its underlying FFmpeg tooling do not reliably handle spaces or special characters in the root directory path, which leads to file/argument parsing failures.
Close the software.
Move the entire program folder to a shallow path with only English letters and digits, with no spaces or special symbols — for example D:/pyVideoTrans.
Re-launch sp.exe from the new location.
If the problem persists, also check that the selected video filename itself contains no spaces, Chinese characters, or special symbols (e.g. use myvideo.mp4 instead of names with spaces/?/*/emoji).
If it still fails after that, provide the latest log from the logs/ folder (last ~30 lines) for further analysis.
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