Is this input something ffmpeg resolves itself rather than a local file?
Covers URLs, protocol prefixes (concat:, lavfi:, pipe:), a bare - for
standard input, and a leading digit — which is how ffmpeg reads a raw stream
specifier like 0 or 1 for a numbered input. A relative filename beginning
with a digit is therefore treated as a stream specifier, which is the safer
mistake: validation is opt-in, so a caller can disable it, whereas silently
stat-ing a nonexistent relative path would not be noticed.
Is this input something ffmpeg resolves itself rather than a local file?
Covers URLs, protocol prefixes (
concat:,lavfi:,pipe:), a bare-for standard input, and a leading digit — which is how ffmpeg reads a raw stream specifier like0or1for a numbered input. A relative filename beginning with a digit is therefore treated as a stream specifier, which is the safer mistake: validation is opt-in, so a caller can disable it, whereas silently stat-ing a nonexistent relative path would not be noticed.