Hi Ron, Here's what I do, I hope it helps. I generally create a DVD with 6 or 7 different clips that I output from Cinelerra as Raw DV files.
I add up the total running time of all the clips (the one I'm currently working on is 6 clips totalling 71 minutes). I take that over to http://www.3ivx.com/support/calculator/ and input the size of the disk I'm going to use (4200 MBytes), my running time (01:11:00), and my audio bitrate (256 KiloBits/sec). The calculate button tells me I can have a max of 7820 kiloBits/sec. I then create a shell script to run through all of my clips in succession using 2 pass encoding like: ffmpeg -i clip01.dv -pass 1 -passlogfile log01.txt -target ntsc-dvd -aspect 16:9 -b 7820k -maxrate 8000k -ab 256k -ar 48000 -ac 2 01_output_pass1.mpg ffmpeg -i clip01.dv -pass 2 -passlogfile log01.txt -target ntsc-dvd -aspect 16:9 -b 7820k -maxrate 8000k -ab 256k -ar 48000 -ac 2 01_output_pass2.mpg Note the "-b 7820k" I took from the website. This has never resulted in files too big to burn onto a disk and it seems to get very close to the file size limit for a DVD. I'm sure there may be other ffmpeg switches that would help me with better quality, I'd love to hear input from anybody. But, I've been generally happy with the quality and it's pretty much a cut and paste operation at this point so I haven't been experimenting much. Pat On Tue, Mar 3, 2009 at 12:14 PM, John Detwiler <[email protected]>wrote: > Ron, > > That's good to hear. > > My big question, still outstanding, is: "HOW do we control the size/rate of > those .mpgs?" > > I believe that neither dvdauthor or dvdstyler will add much overhead, nor > should they make the .mpgs any more compact. > But, when rendering in Cinelerra, and when combining in ffmpeg, the only > parameter that seems to bear upon size and bit-rate > would be the -target option. > > Do you use something different from '-target ntsc-dvd' ?? > > (BTW: For Cinelerra rendering, I use the ffmpeg pipe: "ffmpeg -f > yuv4mpegpipe -i - -y -target dvd -flags +ilme+ildct %") > > Unless you (somebody) have applicable experience, I guess I'll just futz > with the ffmpeg parameters to see what happens. > > Thanks again. >
