Hey all... I've been chatting on another thread about mpeg2trans
and the structure of the streams produced by the ivtv cards. A couple of
questions about the recording modes of the ivtv chip:
- Aside from encapsulation (TS/PS), is there any discernable difference
between the different types of capture types? PS, TS, PES_AV, DVD, SVCD,
DVD_S1, DVD_S2 all seem to produce the same MPEG structure... at least the
last time I looked.
- Some time between the dim, distant past 18 months ago when I made a
bunch of 8mm tape captures (ivtv-0.1.9), the default GOP structure in the
driver appears to have changed from open to closed. Does anyone know if
the ivtv chip actually utilizes previous GOP reference frames for a B
frame when set to open, or is it just a placebo?
- I've done a little searching on adaptive GOP sizes for the ivtv
chip. For example::
http://www.poptix.net/ivtv/Apr-2003/msg00800.html
Has anyone discovered whether or not this is true? I've seen some rather
ignorant choices made (setting I-frame on first field of an interlaced
scene change, for instance) on the current fixed GOP size. I think
adaptive GOP size could measurably increase the quality/bitrate if the
chip is clever enough.
-Cory
--
*************************************************************************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
*************************************************************************
_______________________________________________
ivtv-devel mailing list
[email protected]
http://ivtvdriver.org/mailman/listinfo/ivtv-devel
