Hi! Francesco Fumanti wrote:
>>>Would it be possible to add the possibility to check the opened >>>stream for data breaks? >> >>You mean, missing frames? > > > I don't know exactly what kind of errors could be relevant. > > > >>We do that for video frames when the file is indexed. If you start >>dvbcut on the command line, you will see the messages about missing >>frames. > > > Thanks for telling me this. Consequently, I will now start dvbcut from > the command line. However, would it be possible to make that information > available in a pane in the application, so that it is also available > when dvbcut is started from the menu? The program can't tell whether it was started from the menu or manually. >>This function is not very precise, though. You sometimes get false >>alarms when the input file contains wrong timestamps, for example. > > > The few files that I tried since I know about starting dvbcut from the > command line, did not return any error. > > You say that sometimes it gives false alarms. What about the other way > round: does it sometimes miss real errors? Of course that might happen as well. But there is only a very small chance that a single error isn't detected. If several errors occur in a run, they're not always reported individually because we usually can only tell if there are missing frames in a GOP or not. >>>Moreover, it would be great if this check could be enhanced with >>>the option to fix the data break when possible. >> >>Maybe we could. But many players handle missing frames quite well >>(usually by speeding up and slowing down the surrounding frames a >>little). All we could do in dvbcut is fill the gap with black frames >>(or some milliseconds of silence in case of audio), or maybe repeat >>the preceding frame in some cases. The result would probably be >>worse. > > > Based on your explanation, it might probably be the best to leave the > errors in the file and let the player handle them. This way, we can also > benefit from the future improvements made to the error handling code. Right. > In any case, if you are adding some error fixing code to dvbcut, I would > appreciate if it was optional so that the user can always turn it off. Well, there already is some (minor) error fixing code. Timestamp correction, for example, to eliminates rounding errors. >>>(MPEG Streamclip >>>http://www.squared5.com/svideo/mpeg-streamclip-win.html offers that >>> feature.) >> >>I wonder how they do it, and what the result looks/sounds like. There >> aren't exactly many ways to recover missing audio/video data... > > > I don't know either. > > > On the mailing list I read that the difference between the export of a > file in a format containing DVD in the format name, and the same without > DVD, is that the first has a sectorsize optimised for DVD. DVD format has a pack size of 2 KB and additional empty sectors for navigation (which can be filled in later by dvdauthor or similar programs). It's similar to the output of "mplex -f8". Ordinary MPEG format uses longer packs (of varying size) and lacks the NAV sectors. If your DVD player can handle it (software players like mplayer, vlc or xine can), this is the preferred format because it takes up a little less disk space. > Could you please tell me why dvbcut also offers an export based on > libavformat? Does libavformat also ship with dvbcut, or is it in a > separate package of the dvbcut application? An old version of ffmpeg (libavformat + libavcodec) ships with the source code. You should also be able to compile dvbcut with more recent versions, however. I think the libavformat output was included for two reasons: first, it provides the TS format export (which is rarely used), and second, dvbcut's internal muxer wasn't particularly good at the beginning. > This brings me to another possible RFE: > > Could you please add to the export methods of dvbcut the possibility to > export the file in the same format it was opened? For example, let's > assume that I open a movie.ts file in dvbcut and cut commercial out of > it. Would it make sense to copy the portion that have not been touched > simply into the exported file without modifications; I don't know if > something has to be done at the points comming together after cutting > the commercial out of it!? The video frames around the cut point are re-encoded to form a new (complete) GOP - that's required for frame-accurate cutting. The rest of the video frames and the audio tracks are copied verbatim, therefore there is no conversion loss. Note that this is independent of the output format - it's only the container format that changes, the audio and video streams are the same in all cases. -- Michael "Tired" Riepe <[EMAIL PROTECTED]> X-Tired: Each morning I get up I die a little ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ DVBCUT-devel mailing list DVBCUT-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dvbcut-devel
