[FFmpeg-user] asubboost and asupercut

[Michael Koch]

Am 27.11.2020 um 22:47 schrieb Paul B Mahol:
> On Fri, Nov 27, 2020 at 10:40 PM Michael Koch <astroelectronic at t-online.de>
> wrote:
>
>> Am 27.11.2020 um 20:50 schrieb Paul B Mahol:
>>> On Fri, Nov 27, 2020 at 8:24 PM Michael Koch <
>> astroelectronic at t-online.de>
>>> wrote:
>>>
>>>> Am 27.11.2020 um 19:25 schrieb Paul B Mahol:
>>>>> On Fri, Nov 27, 2020 at 7:09 PM Michael Koch <
>>>> astroelectronic at t-online.de>
>>>>> wrote:
>>>>>
>>>>>> Hello,
>>>>>>
>>>>>> I have a few questions about the asubboost and asupercut filters.
>>>>>>
>>>>>> -- In asubboost it's not yet clear how the block diagram of the filter
>>>>>> looks like. Especially the "decay" and "feedback" options are unclear.
>>>>>> What's the input of the the delay line? Before or after the low pass
>>>>>> filter? Where does the feedback go to? Before or after the lowpass
>>>>>> filter? I have attached a sketch of a possible block diagram, but it's
>>>>>> only a wild guess.
>>>>>>
>>>>> This filter just adds delayed sub frequencies set by cut off frequency
>>>> back
>>>>> to output. Decay sets decay of old sub echo in buffer and feedback sets
>>>> how
>>>>> much
>>>>> new sub frequencies are added to the delay buffer.
>>>> Sorry, I didn't understand it. I think this filter could be explained
>>>> much better with a block diagram.
>>>>
>>>>
>>>>>> -- Is it correct that the "slope" parameter effectively changes the
>>>>>> cutoff frequency, but doesn't change the steepness (dB / octave) of
>> the
>>>>>> filter?
>>>>>>
>>>>> It changes steepness, not cutoff.
>>>> What's the unit of the "slope" option?
>>>>
>>>>
>>> 1 / octave, can be set as dB unit, eg. -20dB, 0dB or 1 is max value.
>>>
>>> Use mentioned mpv command for the reason, as it displays curve.
>> The command does not work on my computer. I did download mpv.exe and run
>> the command line. mpv exits immediately, no output, no error message.
>> When I run mpv without any options, then a mpv window opens.
>>
> Make sure you run it inside power shell or cmd.exe and make sure you tried
> mpv.com too.

Now with mpv.com it works. But the version doesn't yet have the 
asubboost filter. With other filters it works.

Michael