Josef Wolf wrote: >Hello! > >[ I hope I am on-topic here. I have considered to post this to the > tuxbox-forum, but decided to post it here because it has more to > do with stream encodings than with the dbox2.] > >I'm trying to transport live streams over a 10BaseT[1] network. With >most channels, there is no problem. But on some programs (most notably >the german ARD) the bitrate is changing pretty much. After a lot of >investigations, i've got some assumptions: > >- Most of the bandwidth is consumed by the video-pid (pid 101). This is > not really a surprise. I mention this here only because I need a reason > to ignore the other PIDs :) > >- Most of the time the bitrate on the video-pid is quite low (about > 2000..3500 TS packets per second, which gives something below 7MBps). > But sometimes (every 10..20 minutes) the bitrate raises dramatically[2] > for a couple of seconds (sometimes just one second, sometimes up to 20 > seconds) and comes down again to the 2000..3500 range. I really don't > understand what is going on here. How come this dramatic raise without > increase in the motion or in picture-details? Is this raise really > caused by the video stream? > > > >- Next, I checked how much stuffing (via adaptation field) is inserted. > It seems to me that about 6..8% stuffing is inserted. > >My guess is that with recoding the TS into PS, it should be possible to >avoid this stuffing. In addition, the TS header (another 2%) can be >avoided. With a little luck, this might be sufficient to get the bitrate >below 10MBps (check footnote [2]). > >Can anyone confirm or correct my assumptions or have any other idea what >might be going wrong here? > > > Since the TS is constituted of more than the Video ES, the bandwidth occupied might very well depend on other factors. I remember Johannes once saying that the EIT rate on the German Das Erste is quite high. >I would like to try this recoding (TS->PS). Extracting PES from the TS >is not really a probem. But unfortunately, I could not find any >description how PS streams are to be constructed. Any pointers? > > You can probably, check out replex from the Metzler bros, http://www.metzlerbros.org/dvb
