[FFmpeg-user] Increasing audio

[Paul B Mahol]

On 4/3/17, William Caulfield <william.caulfield at contentbridge.tv> wrote:
> On Sat, Apr 1, 2017 at 1:21 PM, Cecil Westerhof <Cecil at decebal.nl> wrote:
>
>> I was asked to make videos during a ToastMasters contest. I had
>> ordered a microphone for this, but sadly it did not arrive in time. So
>> I needed to use the internal microphone from my Canon HS60 SX. Being
>> away about ten meters from the speakers, their voices are much to
>> soft. So I needed to pump up the audio. I did this with:
>>     ffmpeg -y -i speaker.MP4 -vcodec copy -af volume=3 speakerAudioInc.MP4
>>
>> Is that the correct way, or is there a better way?
>>
>>
>>
>> --
>> Cecil Westerhof
>> Senior Software Engineer
>> LinkedIn: http://www.linkedin.com/in/cecilwesterhof
>> _______________________________________________
>>
>
>
>
> Not really an answer to your question, but speaking as an audio engineer:
>
> The boost you want is around 2.5Khz. That's where vocals are understood.
> 700hz up to 3.5khz is probably a good range.
> Avoid boosting below 400hz (muddy) and above 10Khz (zingy).
>
> I guess I'm suggesting some sort of EQ before the volume increase. Not sure
> how that is done in FFMPEG.

With equalizer filter.