flv with no video length

[tv3636]

I have a video downloader add-on for Firefox which can kind of download live streams, but when they are done downloading the flv has no video length. The video still plays, but you can't skip around, edit it, etc. What I mean by video length by the way is that it will say 1:02/--:-- in VLC media player.

Anyway, is there a way to either correct this or convert it to another format which will correct it?
Thanks!

[tomlee59]

Information about the length is conveyed as metadata. Not all flash clips contain this information, making it impossible for you to move the slider around. Sometimes this is by design (to force you to watch the whole thing), sometimes it's because the creator was lazy.

[poisondeathray]

The other possibility is that it might be damaged

What happens when you use another player eg. kmplayer, smplayer ?

You can try extracting the raw streams with flv extract, then re-wrap it with mkvmergegui (mkv), or yamb (mp4)

[tv3636]

It's the same issue with any player, it's just the file itself that's messed up. I'll try flv extract out, thanks for the link.

[gll99]

To see if the duration is set, you could use simple ready made tools like Gspot but that's too easy. One way I use to see the metadata is with ffmpeg. In my case I mostly use it within vb but it can easily be done in a bat file. It's much longer to explain than to actually do it.

ie... put ffmpeg.exe in the same directory as the flv and make a small 2 line bat file like this example: test.bat

ffmpeg.exe -i "Your File name.flv"
pause

You can use different directories for ffmpeg.exe and the flv but then you need to specify the full path.
The -i parameter is needed to identify the input file that follows
The double quotes are needed if it's a long filename with spaces.
No output file is stated to deliberately cause an error to terminate the bat file after it reads the input file.
The pause command allows you to read the dos box that will open when you run the bat file in the window explorer otherwise it would close itself.

Check to see if the duration is set. The issue could be more a lack of frame indexing rather than a metadata problem.

FFmpeg can handle other file types also. So far, I've tried it with the avi container, wmv, rmvb, mov and mpeg among others. I can't promise they will all work for everyone else since it may require certain codecs already be installed on your system but it works for me.

In a similar way, I also use ffmpeg and/or mencoder to convert files, create divx from dvd as wanted etc... but that's another story.

[tv3636]

Well, flv extract could accurately extract the audio cleanly (i.e. with a starting and ending time) but when I try to extract just video nothing happens. By just checking off video and dragging my flv there nothing happens at all :\

And gl99: I know that there is no duration set, but I want to know how I can set the duration myself.

[gll99]

I don't have a broken flv file to test with but using ffmpeg this small bat file might remux your flv and reset the index. A modification of the code could also be used to convert it to another format.

ffmpeg -i "inputfile.flv" -vcodec copy -acodec copy outfile.flv
pause

It's been a while but I'm pretty sure this works in a bat file with mencoder

mencoder inputfile.flv -o outfile.flv -forceidx -ovc copy -oac copy
pause

I always use a pause so I can read the dos window before closing.