Re: [Discuss-gnuradio] Comb Filter

[Prateek Dayal]

Thanks .. my concern right now is to get a video decoding system
working. Speed is not the issue. Once I am able to do this, I can fine
tune different modules. I also have to find out how to convert the
decoded intensity (Y) values to something that can be displayed by the
display driver ....

Regards,
Prateek


On Tue, 4 Jan 2005 15:43:17 -0500 (EST), cswiger <address@hidden> wrote:
> On Tue, 4 Jan 2005, Prateek Dayal wrote:
> 
> > Can you please suggest  a site, where I can find the specifications
> > for the comb filter etc for NTSC decoding. From the books that I have,
> > it is not very clear ...
> >
> 
> Just for giggles today I did a little research into comb filters
> and found this page, altho it's audio application:
> 
> http://ccrma.stanford.edu/~jos/pasp/Feedforward_Comb_Filter_Amplitude.html
> 
> and other pages on the same site. A basic comb filter is pretty easy to
> create:
> 
> comb = gr.fir_filter_fff (1, [1, 0, 0, 0, 0, 1])
> 
> will give you 5 notches between 0 and sample rate, etc. However I didn't
> see anything specific to ntsc seperation (that I could understand ;).
> I used that with some noise and the fft display and it indeed makes a comb
> filter.
> 
> Like Eric said using something like the above might not be fast
> enough for real-time video.
> 
> --Chuck
> 
> 


-- 
Prateek Dayal
B.Tech 4th Year
ECE
IIT Guwahati

www.geocities.com/pmd_iitgw