[FFmpeg-devel] [PATCH] avfilter: add showfreqs filter

Paul B Mahol onemda at gmail.com
Mon Aug 10 21:55:53 CEST 2015


On 8/10/15, Lou Logan <lou at lrcd.com> wrote:
> On Mon, 10 Aug 2015 15:51:24 +0200, Paul B Mahol wrote:
>
> [...]
>
>> + at section showfreqs
>> +
>> +Convert input audio to video output, representing the audio power
>> spectrum.
>
> You can remove that comma.
>
>> +Audio amplitude is on Y-axis while frequencies are on X-axis.
>
> Audio amplitude is on Y-axis while frequency is on X-axis.
>
>> +The filter accepts the following options:
>> +
>> + at table @option
>> + at item size, s
>> +Specify size of video.
>
> For the syntax of this option, check the @ref{video size syntax,,"Video
> size" section in the ffmpeg-utils manual,ffmpeg-utils}. Default is
> @code{1024x512}.
>
>> + at item mode
>> +Set display mode.
>> +
>> +It accepts the following values:
>> + at table @samp
>> + at item line
>> + at item bar
>> + at item dot
>> +
>> +Specify how each frequency bin will be represented.
>
> The above line seems to be misplaced.
>
>> + at end table
>
> Default is @code{bar}.
>
>> + at item ascale
>> +Set amplitude scale.
>> +
>> +It accepts the following values:
>> + at table @samp
>> + at item lin
>> +Linear scale.
>> +
>> + at item sqrt
>> +Square root scale.
>> +
>> + at item cbrt
>> +Cubic root scale.
>> +
>> + at item log
>> +Logarithmic scale.
>> + at end table
>
> Default is @code{log}.
>
>> + at item fscale
>> +Set frequency scale.
>> +
>> +It accepts the following values:
>> + at table @samp
>> + at item lin
>> +Linear scale.
>> +
>> + at item log
>> +Logarithmic scale.
>> + at end table
>
> Default is @code{linear}.
>
>> + at item win_size
>> +Set window size.
>> +
>> +It accepts the following values:
>> + at table @samp
>> + at item w16
>> + at item w32
>> + at item w64
>> + at item w128
>> + at item w256
>> + at item w512
>> + at item w1024
>> + at item w2048
>> + at item w4096
>> + at item w8192
>> + at item w16384
>> + at item w32768
>> + at item w65536
>> + at end table
>
> Default is @code{w2048}.
>
>> + at item win_func
>> +Set windowing function.
>> +
>> +It accepts the following values:
>> + at table @samp
>> + at item rect
>> + at item bartlett
>> + at item hanning
>> + at item hamming
>> + at item blackman
>> + at item welch
>> + at item flattop
>> + at item bharris
>> + at item bnuttall
>> + at item bhann
>> + at item sine
>> + at item nuttall
>> + at end table
>
> Default is @code{hanning}.
>
>> + at item overlap
>> +Set window overlap. In range @code{[0, 1]}. Default is 1, which means
>> optimal overlap
>> +for selected window function will be picked.
>> +
>> + at item averaging
>> +Set time averaging. Setting this to 0 will display current maximal peaks.
>
> Default is 1.
>
>> + at item color
>> +Specify list of colors separated by space or by '|' which will be used to
>> draw channel
>> +frequencies. Unrecognized or missing colors will be replaced by white.
>> + at end table
>
> Can you list the acceptable colors? Would it be too annoying to allow
> usage of the colors listed in ffmpeg-utils?

Color by name are somewhere listed otherwise all colors set in hex are accepted.

>
> Please check that I got the defaults correct.

Defaults are fine.

> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>


More information about the ffmpeg-devel mailing list