Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-20 Thread Steven M. Schultz
On Sat, 20 Dec 2003 [EMAIL PROTECTED] wrote: > > > Ok. I noticed that for some chapters on the DVD, the average bitrate > > > reported by mplex was almost 50% of the max bitrate! What does this > > Could you please comment on this? If the avg is 50% of the max, does it > mean that I can afford

Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-20 Thread mjpeg
>From "Steven M. Schultz" <[EMAIL PROTECTED]> on 19 Dec 2003: > > On Fri, 19 Dec 2003 [EMAIL PROTECTED] wrote: > > > Ok. I noticed that for some chapters on the DVD, the average bitrate > > reported by mplex was almost 50% of the max bitrate! What does this > > mean? Could you please comment o

Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-19 Thread Steven M. Schultz
On Fri, 19 Dec 2003, Matto Marjanovic wrote: > > > [You can specify "-S mode=mono" to y4mscaler, and it will treat the source > as a mono stream. Then, in addition to zeroing the output chroma channels, > it will skip scaling them altogether.] Cool! I just killed the enc

Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-19 Thread Matto Marjanovic
[a footnote:] ... > This particular movie is black and white so the chroma is killed with > 'y4mshift -M' (sets U and V to 128). ... >mpeg2dec -s -o pgmpipe foo.vob | \ > pgmtoy4m -i t -a 10:11 -r 3:1001 | \ > y4mshift -M | \ > y4mscaler -v 0 -S option=sinc:8 -O

Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-19 Thread Steven M. Schultz
On Fri, 19 Dec 2003 [EMAIL PROTECTED] wrote: > Ok. I noticed that for some chapters on the DVD, the average bitrate > reported by mplex was almost 50% of the max bitrate! What does this mean? Ah, I see my posting made it out - I never saw it come around. > > After discarding 80 to

Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-19 Thread mjpeg
>From "Steven M. Schultz" <[EMAIL PROTECTED]> on 18 Dec 2003: > You set the maximum bitrate and then adjust -q so that the Average > is ~10% lower than the Peak rate. Ok. I noticed that for some chapters on the DVD, the average bitrate reported by mplex was almost 50% of the max bit

Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-19 Thread Steven M. Schultz
On 19 Dec 2003, Florin Andrei wrote: > You mean that for whole movies (> 1 hour) or for smaller scenes? For the movie as a whole. Shorter scenes will, as you have seen, run up against the limit and there's nothing "wrong" about that. The guidline often is given as 20%

Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-19 Thread Florin Andrei
On Thu, 2003-12-18 at 20:23, Steven M. Schultz wrote: > You can set the bitrate to 9000 kbits/sec but with a high '-q' the > encoder will only use a fraction of the maximum bitrate. Lower -q > and watch the encoder come closer to the maximum rate. > You set the maximum bitrate and then adjust -q

Re: [Mjpeg-users] Filesize/bitrate vs. quality

2003-12-18 Thread Steven M. Schultz
On Thu, 18 Dec 2003 [EMAIL PROTECTED] wrote: > In trying to make a VBR MPEG1, there is a tradeoff between higher > filesize/bitrate vs. quality. That's always true - it's not VCD specific (and it sounds like you are creating a XVCD). > To get the same visual quality (i.