On Wed, Feb 23, 2005 at 12:24:49AM +0100, Robert Schlabbach wrote: > From: "Johannes Stezenbach" <js@xxxxxxxxxxx> > > It's all undefined, as each demod hardware and driver has it's > > own idea about them. > > Which is not good. Each driver should be required to norm its signal > statistics, e.g. to a percentage. Only the driver can "know" how to do > this, and if the driver doesn't do it, the application can't do it either. > > The Linux API should define exact value ranges for every statistic which > every driver would be required to scale its hardware readings to. Then the > statistics would actually be useful to applications for display purposes. Yeah. Some values *are* scaled into 0..0xffff (e.g. snr), but that still doesn't mean that you get well-defined values. E.g. some cards will return 0x1234 and others 0x2345 for the same input signal. I don't know how you want to calibrate this, even if you'd have a zoo of cards to compare against each other I guess that for consumer equipment even two "identical" cards will return different values... Johannes
