[FFmpeg-user] Fade in filter and alpha channel fade in text

Joshua Grauman jnfo-c at grauman.com
Sun Aug 12 19:07:12 EEST 2018

Hi all,

I am combining various effects, and I noticed that when I fade in a video 
using the [in]fade=t=in:st=2:n=24[out] syntax, and I fade in text using 
alpha='if(lt(t,2),0,if(lt(t,3),t-2,1))', that they both fade in roughly at 
the same time, but both are not linear. I'm guessing the fade=in uses a 
sine wave or something to fade in the video, while clearly the text fade 
is based on a linear fading of the alpha channel. Am I correct that the 
video fade in is a sinusoidal fade? Does anyone know offhand how I could 
get the text fade to match the video one?


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