Hello,
I'm using a DVB card Hauppauge WinTV Nova-S on a linux Debian box, and I developed a software in order to get SNR, Viterbi, lock, status and strength signal values. For that, I used drivers and get inspired from dvbtune (dvbtools) software source code. - I use the DVB drivers found here: http://www.linuxtv.org/download/dvb/ --> OK, that works - I use the DVBTUNE software: http://www.linuxstb.org/dvbtune/index.shtml --> OK, that works, but I still have some problems to get the right values (units) for the following values: - SNR (especially) ; - Signal Strength ; - Viterbi ; - etc... In order to get the SNR value, I used the following lines in the "tune.c" source code: ------------------------------------------ strength=0; ioctl(fd_frontend,FE_READ_SNR,&strength); fprintf(stderr,"SNR: %d\n",strength); ------------------------------------------ My questions are : - What's the unit of the value FE_READ_SNR to be displayed ? Usually, a big number is displayed, but I want to display this value in dB, so is there any math formulae to apply, in order to get this value in dB ? If yes, what is it ? (*) - Same questions for FE_READ_BER, FE_READ_SIGNAL_STRENGTH (*) For example, if I install this DVB card on a Windows box, with WinTV software tools on Windows, I can see the SNR level in a color bar, and the value expressed in dB, such as in the example provided in this image: http://www.hauppauge.fr/sup/cap/nexus2.jpg I read the following documentation: http://www.linuxtv.org/download/dvb/linux-dvb-api-1.0.0-pre1.pdf but I didn't find answers to my questions. Am I on the right mailing-list to ask for these informations ? Otherwise, where could I post ? Thanks a lot for your help. -- Samuel Torton http://www.ncslab.com -- Info: To unsubscribe send a mail to [EMAIL PROTECTED] with "unsubscribe linux-dvb" as subject.
