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<DIV><SPAN class=287134510-20092006><FONT face=Arial
size=2>Hi,</FONT></SPAN></DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial size=2>I'm not sure if this
is the right place for this so I apologise in advance if it's not. I'm just
about to start working with a V4L driver and it occurs to me that my
understanding of the differences between a DVB driver and a v4l driver are hazy
at best. Therefore I'd appreciate a steer to a decent overview/summary document
(there doesn't appear to be such a thing on linuxtv.org) comparing the two
mechanisms.</FONT></SPAN></DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial size=2>From what I've
gleaned the DVB interface provides access to a raw MPEG stream via PIDs etc via
entries /dev/dvb/adapterX/*, whereas the V4L interface provides access via
/dev/video to an already decoded video stream. Doesn't this mean that the
quality of the resultant image is dependant upon the quality of the card
manufacturer components (i.e. cheap units are likely to give poor perfomance)
whereas with DVB devices a cheap device should give identical results to a
higher quality unit (assuming a decent tuner lock) as in both cases we're just
getting a bitstream? Also, for recording systems (I intend to use VDR) we'll be
recording in MPEG or whatever so isn't there an additional decode/encode
process? I.e.</FONT></SPAN></DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial size=2>
DVB(MPEG)->VIDEO->MPEG->file</FONT></SPAN></DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial size=2>compared with
</FONT></SPAN></DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial size=2>
DVB(MPEG)->file</FONT></SPAN></DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial size=2>and if so, wouldn't
simpler DVB devices be better for PVR purposes?</FONT></SPAN></DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial
size=2>Thanks</FONT></SPAN></DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=287134510-20092006><FONT face=Arial
size=2>Mark</FONT></SPAN></DIV></BODY></HTML>
<BR>
<P><FONT SIZE=2>--<BR>
No virus found in this outgoing message.<BR>
Checked by AVG Anti-Virus.<BR>
Version: 7.1.406 / Virus Database: 268.12.5/451 - Release Date: 19/09/2006<BR>
</FONT> </P>