I want to reduce WEBP file size. I'm using https://github.com/tanersener/ffmpeg-kit library to convert my video .mp4 to .webp
Input File MP4 Size - 800kb
Output File WEBP size - 5.22 MB

Commands which i used

ffmpeg.exe -i outputbitrate.mp4 -vcodec libwebp -filter:v fps=fps=20 -lossless 1 -loop 0 -preset default -an -vsync 0 -vf scale=512:512:force_original_aspect_ratio=decrease,format=rgba,pad=512:512:-1:-1:color=#00000000 finalout.webp

I tried with compress_level,quality also. which is not reducing the output size.
in mycase, the output should be less then 512kb. how to achieve this.

Any articles or sample code will be very helpful. Thanks