[FFmpeg-user] Blur the Background with a Gradient

[Víctor Paesa]

Hi,

On 8/25/14, Lou <lou at lrcd.com> wrote:
> On Mon, 25 Aug 2014 15:31:06 +0800
> Qianliang Zhang <zhangqianliang at gmail.com> wrote:
>
>> May just use boxblur. Because I don not want to make a gradient for every
>> different size.
>
> Should be a trivial task if you script it with ffprobe to get the input
> frame size: https://trac.ffmpeg.org/wiki/FFprobeTips
>

You don't need to use the convert command: you may use the qeq filter,
and that selfs adapts to whatever is your input size.

ffmpeg -i my_input_video -vframes 1 \
  -vf 'geq=lum=255*sin(PI*X/W)*sin(PI*Y/H):cb=128:cr=128,format=gray'
-y gradient.png

Regards,
Víctor