How to watch video file while it is still being written?

[MalickT]

I am using WMP Home Cinema to watch movies. What I do is I copy video file from BD to HDD and then watch the movie from HDD (So that I do not have to listen BD-drive annoying sound). The copying progress takes long time and so I would like to start watching the movie while copying is in progress.

Right now when like 10% of the movie is copyd. I can open the movie with WMP-HC and start watching it. Great, but I can only watch beginning of the movie then it stops at 10% of the movie, even when copying progress is finished by then.

Is there a way to set WMP HC to refresh the opened file or something?

[LoRd_MuldeR]

As far as the file system is concerned, this totally depends on how the individual applications try to open the file. If the writing application has opened the file with exclusive write-access (i.e. no read access sharing), then other applications won't be able to access the file until it gets closed - not even for reading. But even if the writing application has opened the file with read access sharing, other applications won't be able to open the file, except for reading with write access sharing! For example, if the reading application tries to open the file with exclusive read access, opening the file is still going to fail. See here (http://msdn.microsoft.com/en-us/library/windows/desktop/aa363858%28v=vs.85%29.aspx) for details, especially dwDesiredAccess and dwShareMode.

In addition to that, whether an "incomplete" file can be played at all, totally depends on the file format. For example, in a TS (MPEG Transport Stream) file all data is wrapped in separate (and mostly independent) packages, each with it's own separate header. Such files can play, even when incomplete. On the other hand, there are file formats like MP4 (MPEG-4 Part 14) and the very similar MOV, where all data is stored in one big chunk - no separate headers at all. Only way to access the data is with the help of the global tables. If those tables are stored at the very end of the file - which will be the case more often than not - there's no way to play the file until it really is complete.

Last but not least, VLC Player or MPlayer may be your best bet for trying to play an incomplete file ;)

[MalickT]

Thank you for your reply. I AM able to play the incomplete file BUT the movie stops at vew minutes into film.

My idea is that when copying progress is about 10% done (a few minutes the beginning of the movie), I start to watch the movie and when movie reaches to 10% of its lenght, the movie would keep playing on to the end because by then the copying progress is finished. Instead it just stops and I have to re-open the movie :(

So I hope someone knows how to set up WMP-HC so it would keep playing the movie to the end.

[Darksoul71]

As (former) Windows user I was never able to get any of the media players out there (MPC, VLC, MPlayer) to play the open video file which was captured / written via DVB-T. They either failed to open the file completely or (as you describe) only were able to play back what was written so far when I opened the file.

Linux on the other hand behaves completely different and every player I usually use (XBMC, VLC, SMPlayer) can easily open up the file currently being written from my DVB-S card. Timeshifting works like a charm.

[Asmodian]

A random idea might be to try a different filesystem? NTFS might be the problem. Probably not but it sounds like it isn't too hard for you to test?

[foxyshadis]

It's not NTFS, it's because the players only check the file size once on load, and then store it until you load again.

It will work if you pass it in through a pipe, since pipes don't have a length; it just reads until it can't anymore. Pipes were made for this. mplayer and its descendants can do that, like:

type movie.avi > mplayer.exe

Alternately, some players will at least bookmark your last location, so you can keep reloading it and never lose your place.