[MPlayer-dev-eng] [PATCH] fix for -srate bug

[Michael Niedermayer]

Hi

On Thursday 28 October 2004 00:39, Ed Wildgoose wrote:
> >>Why did you do this:
> >>>@@ -351,15 +402,34 @@
> >>> src_data.data_in = input ;
> >>> src_data.input_frames = BUFFER_LEN ;
> >>>
> >>>- src_data.src_ratio = 1.999 ;
> >>>+ src_data.src_ratio = 0.4999 ;
> >
> >the bandwidth test simply failed without this change
>
> Sure.  But why?  

because lavc-resample had no point which is attenuated by 3db on upsampling, 
this indeed may be a bug, iam no audiophile, so i dunno if this is needed to 
suppress some audible artefacts, anyway its a very trivial thing to change


[...]
>
> >>I can't quite follow your logic here?
> >
> >as the *2 upsampling is replaced by /2 downsampling the maximum frequency
> >changes from samplingrate/2 -> /4
>
> Hmm, not sure on that...  Can you just double check...?

change it and the bandwidth should be 45% or 180%


[...]

> >my resampler is already supported, just try -af
> >lavcresample=<samplerate>:<filter_length>:<linear_flag>:<polyphase_size>:<
> >cutoff>
>
> Aha.  Interesting.  Can you provide the numbers for this filter to match
> those that were in your test?

the code changed somewhat in the meantime so its not trivial ...
but <samplerate>:32:1:10 or <samplerate>:32:0:14 might be similar

[...]
-- 
Michael

"I do not agree with what you have to say, but I'll defend to the death your
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