Re: [Mjpeg-users] mplex with seek
The PVR s/w runs on PCs only but it records to a format which seems to be referred to as PVA. A free PC tool called PVAStrumento lets you demux this, and it stores the results on my Mac's hard drive. It also fixes any errors which occurred while the transport stream was being received. I then do mplex -V -f 8 -o output.mpg input.mpv input.mpa then use dvdauthor tools ifogen and tocgen to create the VIDEO_TS. That's it. If there's a Unix tool which can replace PVAStrumento that would be even better since the PVR s/w could then record straight over the wire to the Mac (which has a useful 80GB hard drive) and spare me the Uncle Bill experience. :-) It would let me script the process too... O.k. I will see what I can knock up using a stream of my DVB card... hopefully the underlying elementary streams should have identical characteristics. Andrew --- This SF.NET email is sponsored by: FREE SSL Guide from Thawte are you planning your Web Server Security? Click here to get a FREE Thawte SSL guide and find the answers to all your SSL security issues. http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0026en ___ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
Re: [Mjpeg-users] mplex with seek
Hello, The video is encoded by the broadcaster, not me. I have a digital TV receiver connected to a PC which has software which can record the digital TV MPEG2 stream to its hard disk. With a quick demux/remux the recordings can be put onto DVD with no MPEG transcoding at all, i.e. the DVD contains the original broadcast MPEG2 video and MP2 audio. The trouble is that the PC software uses an ordinary clock timer to start and stop the recording, like a normal VHS VCR, so there is usually extra unwanted video at the start and end. The mplex tool lets you chop unwanted material off the end with the -l option but I can't find a way to have the multiplexed output start from n seconds into the streams being muxed. The fact that mplex can segment the input streams into multiple standalone muxed files (e.g. for splitting across CDs) demonstrates that the principle is possible. For me there is no problem with the edit being done on GOP boundaries (as I guess happens with the existing segmentation facility), I don't need frame-accurate editing. All I am looking to do is to archive my favourite programmes to DVD instead of VHS, nothing any more sophisticated, so no intelligent mid-GOP sequence start is required. Any help/direction would be very much appreciated. Regards, Tim Hewett. On Sunday, Jan 19, 2003, at 06:21 Europe/London, Bernhard Praschinger wrote: Hallo I am wondering if there is a way to use mplex such that it starts from n seconds into the audio and video sources given to it. At present it can be made to mplex n seconds of material from the start of the audio and video sources but is there a way to perform a simple kind of editing to cut superfluous material from both the start and end? No. You should edit the video BEFORE encoding it. Some have tired writing a programm to edit MPEG streams. But it does not work reliable. auf hoffentlich bald, Berni the Chaos of Woodquarter Email: [EMAIL PROTECTED] [EMAIL PROTECTED] www: http://www.lysator.liu.se/~gz/bernhard --- This SF.NET email is sponsored by: FREE SSL Guide from Thawte are you planning your Web Server Security? Click here to get a FREE Thawte SSL guide and find the answers to all your SSL security issues. http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0026en ___ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
Re: [Mjpeg-users] mplex with seek
Hallo The video is encoded by the broadcaster, not me. I have a digital TV receiver connected to a PC which has software which can record the digital TV MPEG2 stream to its hard disk. With a quick demux/remux the recordings can be put onto So you have a signal from a digital satelite ? [...] For me there is no problem with the edit being done on GOP boundaries (as I guess happens with the existing segmentation facility), I don't need frame-accurate editing. All I am looking to do is to archive my favourite programmes to DVD instead of VHS, nothing any more sophisticated, so no intelligent mid-GOP sequence start is required. Then you might be interrested in gopchop: http://outflux.net/unix/software/GOPchop/ As far I know the programm works well if you have a SW player. It works not good with HW-devices. auf hoffentlich bald, Berni the Chaos of Woodquarter Email: [EMAIL PROTECTED] [EMAIL PROTECTED] www: http://www.lysator.liu.se/~gz/bernhard --- This SF.NET email is sponsored by: FREE SSL Guide from Thawte are you planning your Web Server Security? Click here to get a FREE Thawte SSL guide and find the answers to all your SSL security issues. http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0026en ___ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
Re: [Mjpeg-users] mplex with seek
The video is encoded by the broadcaster, not me. I have a digital TV receiver connected to a PC which has software which can record the digital TV MPEG2 stream to its hard disk. I've got one myself... a huge leap forward over analog stuff... With a quick demux/remux the recordings can be put onto DVD with no MPEG transcoding at all, i.e. the DVD contains the original broadcast MPEG2 video and MP2 audio. This is not always going to work as DVB allows higher peak bitrates than DVD. The trouble is that the PC software uses an ordinary clock timer to start and stop the recording, like a normal VHS VCR, so there is usually extra unwanted video at the start and end. The mplex tool lets you chop unwanted material off the end with the -l option but I can't find a way to have the multiplexed output start from n seconds into the streams being muxed. The fact that mplex can segment the input streams into multiple standalone muxed files (e.g. for splitting across CDs) demonstrates that the principle is possible. Chuckle... if only it were so simple Half the code-complexity in mplex relates managing run-in / run-out correctly for (S)VCD and and it gets a lot of help from the *encoder* which helpfully places end-of-sequence markers to indicate where a clean split can take place. Anyway, what is possible is that you can cleanly split at *closed* GOPs (one where the initial frames do not refer to the previous GOP. It would not be hard to modify mplex to spot the nearest closed GOP to a specified start-time and start multiplexing from there. I'll see what I can do over the next couple of days. Aside: if you can send me the commands you're using for splitting your DVB files (VDR .vdr's?) I can check it all works myself. Andrew --- This SF.NET email is sponsored by: FREE SSL Guide from Thawte are you planning your Web Server Security? Click here to get a FREE Thawte SSL guide and find the answers to all your SSL security issues. http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0026en ___ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
Re: [Mjpeg-users] mplex with seek
On Sunday, Jan 19, 2003, at 15:06 Europe/London, Andrew Stevens wrote: This is not always going to work as DVB allows higher peak bitrates than DVD. Fortunately digital TV in the UK complies to DVD's 720x572 PAL resolution standard and bit rates tend to average around 4mbit for the best quality channels. I saw 7mbit as a peak once but that's still ok for DVD. We don't have HDTV in the UK, much to the chagrin of some enthusiasts and the balance tends to lean towards more channels at the expense of picture quality (or having cleverer video codecs at the stream head). The only real compatibility issue between broadcast MPEG2 and DVD is that a broadcast transport stream allows the aspect ratio to change on any I-frame boundary, something DVD doesn't allow within an individual disk title. This is not an insurmountable problem though. The trouble is that the PC software uses an ordinary clock timer to start and stop the recording, like a normal VHS VCR, so there is usually extra unwanted video at the start and end. The mplex tool lets you chop unwanted material off the end with the -l option but I can't find a way to have the multiplexed output start from n seconds into the streams being muxed. The fact that mplex can segment the input streams into multiple standalone muxed files (e.g. for splitting across CDs) demonstrates that the principle is possible. Chuckle... if only it were so simple Half the code-complexity in mplex relates managing run-in / run-out correctly for (S)VCD and and it gets a lot of help from the *encoder* which helpfully places end-of-sequence markers to indicate where a clean split can take place. Anyway, what is possible is that you can cleanly split at *closed* GOPs (one where the initial frames do not refer to the previous GOP. It would not be hard to modify mplex to spot the nearest closed GOP to a specified start-time and start multiplexing from there. I'll see what I can do over the next couple of days. Thanks very much indeed. In return I shall point you towards my own contribution to the free software community, an app which lets you backup to DV camcorders. There's already something similar for Linux on sourceforge but this is for MacOS X (my platform) in case that suits you at all. Check out: http://www.versiontracker.com/dyn/moreinfo/macosx/17840 if interested. Aside: if you can send me the commands you're using for splitting your DVB files (VDR .vdr's?) I can check it all works myself. The PVR s/w runs on PCs only but it records to a format which seems to be referred to as PVA. A free PC tool called PVAStrumento lets you demux this, and it stores the results on my Mac's hard drive. It also fixes any errors which occurred while the transport stream was being received. I then do mplex -V -f 8 -o output.mpg input.mpv input.mpa then use dvdauthor tools ifogen and tocgen to create the VIDEO_TS. That's it. If there's a Unix tool which can replace PVAStrumento that would be even better since the PVR s/w could then record straight over the wire to the Mac (which has a useful 80GB hard drive) and spare me the Uncle Bill experience. :-) It would let me script the process too... Andrew Regards, Tim. --- This SF.NET email is sponsored by: FREE SSL Guide from Thawte are you planning your Web Server Security? Click here to get a FREE Thawte SSL guide and find the answers to all your SSL security issues. http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0026en ___ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
Re: [Mjpeg-users] mplex with seek
Hallo I am wondering if there is a way to use mplex such that it starts from n seconds into the audio and video sources given to it. At present it can be made to mplex n seconds of material from the start of the audio and video sources but is there a way to perform a simple kind of editing to cut superfluous material from both the start and end? No. You should edit the video BEFORE encoding it. Some have tired writing a programm to edit MPEG streams. But it does not work reliable. auf hoffentlich bald, Berni the Chaos of Woodquarter Email: [EMAIL PROTECTED] [EMAIL PROTECTED] www: http://www.lysator.liu.se/~gz/bernhard --- This SF.NET email is sponsored by: Thawte.com - A 128-bit supercerts will allow you to extend the highest allowed 128 bit encryption to all your clients even if they use browsers that are limited to 40 bit encryption. Get a guide here:http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0030en ___ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
