Of course, Michael's right.... converting back and forth will in any case degrate quality more than necessary... but if there's no cut tool for MJPEG that's the only possibility!
Assuming that the camera format has a very moderate compression and you use also a very large bitrate for the MPEG2 (probably more than the DVD target implies... try -b 10000k on the RIGHT side of the target switch to overrule the default), I wouldn't expect that you see the difference IF the resulting Video has to be a rather small DIVX-AVI in the end (with [EMAIL PROTECTED]). If not... I would use a suitable MPEG2 bitrate and stay with the cutted MPEG2 video (in 720x576 resolution and burned as a DVD?), i.e. omitting the last conversion! I'm pretty sure ffmpeg can deal with that MJPEG... if you try: "ffmpeg -formats" you can find it in the list of codecs... ;-) But "lav2mpeg" will also work... and is maybe even better since it's more specialized for this kind of conversion... I don't know! BTW, just calling "ffmpeg -i video.avi" will give you information about the video (Duration, Bitrate, A/V codec)... the last 3-4 lines of output...:) ciao Ralph PS: The material from a DV camera is usually interlaced... so you either have to use "-deinterlace" to get a progressive video or "-ildct -ilme" to tell the mpeg2-codec of ffmpeg to support interlaced motion estimation resp. cosine transformation. The coice depends on the device where you want to watch the resulting video... PC or TV! Also DVBcut can not deal with videos, where the interlaced stream is stored seperately with 50Hz half-frames, instead of 25Hz full frames (containing the two half ones). Michael mentioned that already... you can see this also at the ffmpeg output lines... ;-) Am Montag, 30. Juli 2007 19:53 schrieb Footer: > Ralph & Michael, > > Thanks for the thoughts/tips/ideas for what I'm trying t accomplish! > I really appreciate it! And thanks for the GREAT program! In the > past, I've used dvbcut for cutting MPEG from the stream out of my > video capture card (a PVR-250) and it's worked flawlessly. > > The stream I'm trying to convert/cut now is from a new digital camera > we just got (Canon Powershot ES850 IS). How can I tell what type of > codec it is? When I float the cursor over the file name (the .avi > file), it gives me a type: Microsoft AVI Video (ARGH!) and Video > Codec says: mjpg, Audio Codec: Microsoft PCM. I'm a relative newbie > when it comes to this video editing stuff in Linux but so far, I've > been able to get by! And yes, I have messed with AVIDEMUX but not > recently. > > That is quite the complicated ffmpeg line but I shall give it a try > and see what kind of results it gives me. Learned a lot more about > ffmpeg from your message as well! > > Thanks! > > On 7/30/07, Ralph Glasstetter <[EMAIL PROTECTED]> wrote: > > Hi, > > > > Am Montag, 30. Juli 2007 16:54 schrieb Footer: > > > Hey, hey, I never thought about that! Convert it to mpg with ffmpeg > > > on the command line and then use DVBCut? > > > > The only way, if you insist in using DVBcut for cutting an AVI... ;-) > > > > BTW, what codec was used for that AVI-video? DIVX? > > Ever tried AVIDEMUX(2) for cutting it? > > > > > I just tried that and DVBCut > > > didn't like it too much. > > > > You used probabely the wrong switches...? > > > > > But I was able to shrink the file from 168MB > > > to 6MB which is acceptable to me. > > > > That's nearly impossible with adequate quality! > > > > > Would be nice to further cut it as > > > an mpg but I don't know how much more time I'm willing to invest to do > > > that. For what it's worth, here's the line I used to shrink the file > > > (it was 640x480 and this command cut it down to 320x240): > > > > > > ffmpeg -i input_file_640x480.avi -ar 22050 -b 500 -s 320x240 > > > output_file_320x240.mpg > > > > OK, with a bitrate of only 500 bits/sec it's no wonder that you ended up > > with just 6 MB. Could you really see a proper video...? :) > > You have to specifiy "-b 500k" if you want KILObits/sec!!! > > > > But with MPEG2 this also would give a rather bad quality... are you > > really sure that it's a MPEG2 video in an AVI container? I never saw > > that... and with your command line you didn't changed the codec.... > > > > > Would welcome any other ideas!!! > > > > For cutting with DVBcut I would convert the video to a rather large > > bitrate MPEG2 stream to preserve the quality as much as possible (without > > changing the resolution!)... maybe with "-target DVD -s 640x480"... and > > additionally a "-acodec copy", if the audio is already coded in MP2/AC3 > > 48kHz. > > But if not, you have to specify "-acodec mp2 -ab196k -ar 48000", > > otherwise DVBcut probabely does not recognize the Audio channel. > > > > After cutting you can shrink it down again to a AVI/DIVX with > > [EMAIL PROTECTED] and [EMAIL PROTECTED]/22kHz or whatever... > > > > I usually use: > > ffmpeg -i INFILE -f avi -vcodec mpeg4 -b 800k -g 250 -bf 2 -s 640x480 > > -aspect 4:3 -acodec mp3 -ab 128k -ar 44100 OUTFILE > > > > ciao, > > Ralph > > > > > On 7/30/07, Michael Riepe <[EMAIL PROTECTED]> wrote: > > > > Hi! > > > > > > > > Footer wrote: > > > > > Well ... both? > > > > > > > > I doubt that will ever happen. Output, maybe. > > > > > > > > > Although I wouldn't mind taking AVI input and making > > > > > it MPEG output ... When I try open an AVI file for editing, it > > > > > says: "Unknown file type" > > > > > > > > DVB material uses MPEG-2 container formats (PS/TS) exclusively. There > > > > was (and still is) no need to support other input formats, unless you > > > > want to turn dvbcut into a general-purpose video cutting software. > > > > > > > > That, on the other hand, will require massive changes to the code. > > > > I'm afraid you'll have to live with AVI<->MPEG converters. > > > > > > > > Michael. > > > > > > > > --------------------------------------------------------------------- > > > >---- This SF.net email is sponsored by: Splunk Inc. > > > > Still grepping through log files to find problems? Stop. > > > > Now Search log events and configuration files using AJAX and a > > > > browser. Download your FREE copy of Splunk now >> > > > > http://get.splunk.com/ > > > > _______________________________________________ > > > > DVBCUT-user mailing list > > > > DVBCUT-user@lists.sourceforge.net > > > > https://lists.sourceforge.net/lists/listinfo/dvbcut-user > > > > > > ----------------------------------------------------------------------- > > >-- This SF.net email is sponsored by: Splunk Inc. > > > Still grepping through log files to find problems? Stop. > > > Now Search log events and configuration files using AJAX and a browser. > > > Download your FREE copy of Splunk now >> http://get.splunk.com/ > > > _______________________________________________ > > > DVBCUT-user mailing list > > > DVBCUT-user@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/dvbcut-user > > > > ------------------------------------------------------------------------- > > This SF.net email is sponsored by: Splunk Inc. > > Still grepping through log files to find problems? Stop. > > Now Search log events and configuration files using AJAX and a browser. > > Download your FREE copy of Splunk now >> http://get.splunk.com/ > > _______________________________________________ > > DVBCUT-user mailing list > > DVBCUT-user@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/dvbcut-user > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > _______________________________________________ > DVBCUT-user mailing list > DVBCUT-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/dvbcut-user ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? 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