On Sun, May 21, 2017 at 5:48 AM, Carl Eugen Hoyos <[email protected]> wrote:
> You can disable the text demuxer at build time or you can > use the global -format_whitelist option to only allow formats > that you want (without needing any processing). Good to know - but what other surprises lurk that I haven't discovered yet? > You can just store the FFmpeg demuxer type in you DB, ignoring > the mime-type. Can I ask for clarification about one point? I understand that ffprobe returns format (which includes format_name) and a list of streams (which include codec_name). When you say store the demuxer, are you referring to the format or codec? And is it always a demuxer (rather than a muxer) because I'm probing the file, rather than generating it? > I would also appreciate any advice on assembling such a whitelist. > > Why would you disable any formats? Because paranoia is a cheap substitute for perfect knowledge. As I said, I was surprised when ffprobe inspected a text file without complaint, and even reported a video stream. (I expected an error.) Clearly, a text file is not an acceptable source for a video hosting platform that needs to generate preview clips and screenshots from the original. Since I can't know what other surprises are in store, it seemed wise to start by drafting a list of commonly-encountered ffmpeg formats that are *known* to be actual videos until I get a better grasp on the domain. I generated the initial list by running a crawler against a collection of videos I had lying around. My intent was to log rejections, examine the rejected file manually, and if it's actually a video, add the format to the whitelist. -ofer _______________________________________________ ffmpeg-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
