[mythtv-users] Is pcHDTV a DVB card?

[Jonathan Rogers]

Daniel Kristjansson wrote:
> When speaking of ATSC/QAM cards like the pcHDTV cards "DVB" refers
> to the Linux driver API. Recently the V4L and DVB projects have been
> merged, but so long as most of the developers are in Europe the
> name is not likely to change to something less confusing. In Europe,
> "DVB" is not a confusing name, there all Digital Television is "DVB".
> The Linux DVB API actually does nothing DVB standard specific. It
> does do some MPEG-TS specific things, but both DVB and ATSC are
> extensions to MPEG, so this doesn't cause any problems.

So, to userspace apps, ATSC and DVB are quite similar, right? Even much 
of the kernel implementation might be similar. The signal modulation and 
frequencies are different, but that's mostly in hardware. In both 
systems, MPEG transport streams are modulated into an RF signal and 
broadcast. The TS contains MPEG-2 video at one of several standard sizes 
and A/52 or MPEG audio streams. I guess DVB and ATSC might be just as 
different as NTSC and PAL, but general purpose PC hardware is far more 
flexible than analog TV systems, so it isn't too hard to deal with 
differences like video frame size, frame or field rate, and audio encoding.

This situation seems similar to storage devices. Under Linux, various 
types of devices are treated as SCSI devices, though they aren't 
attached to the machine by SCSI buses. USB mass storage, IEEE-1394, 
ATAPI (via ide-scsi) and increasingly ATA hard drives (via libata) are 
presented to userspace as SCSI devices with names like /dev/sda and 
/dev/sr0. I think it's been like that under WinNT for even longer than 
Linux.

Jonathan Rogers