I am trying to move a shape (an image) over a background image to each corner. Here is the video example I generated with ffmpeg.
As you can see from the example, at the end of the video the shape is not positioned on the top right corner as it should be:
Here is the ffmpeg command I use:
ffmpeg -i background.jpeg -loop 1 -i logo.png -filter_complex "[0]scale=300:250[s0];[1]format=gbrap[s4];[s0][s4]overlay=x=if(between(t\\,0.0\\,0.8)\\,lerp(0.0\\,240.0\\,round((t-0.0)/0.8*100)/100)\\,if(between(t\\,0.8\\,2.2)\\,lerp(240.0\\,0.0\\,round((t-0.8)/1.4*100)/100)\\,if(between(t\\,2.2\\,3.0)\\,lerp(0.0\\,240.0\\,round((t-2.2)/0.8*100)/100)))):y=if(between(t\\,0.0\\,0.8)\\,lerp(0.0\\,200.0\\,round((t-0.0)/0.8*100)/100)\\,if(between(t\\,0.8\\,2.2)\\,lerp(200.0\\,200.0\\,round((t-0.8)/1.4*100)/100)\\,if(between(t\\,2.2\\,3.0)\\,lerp(200.0\\,0.0\\,round((t-2.2)/0.8*100)/100))))[s5]" -map "[s5]" -c:v libx264 -crf 0 -pix_fmt yuv420p -t 3.0 video.mp4
- video is 300x250
- logo.png is the blue shape (width=60px, height=50px)
- the coordinates are set as follow: 0s: x=0,y=0 / 0.8s: x=240px,y=200px / 2.2s: x=0,y=200px / 3s: x=240px,y=0
I am using lerp to retrieve the right position depending on the current time t.
It seems like the last frames are not played.
I tried to:
- set a framerate (30 & 100) to the logo.png input,
- round the value given by lerp,
- use setpts to define a number of frames.
But I do not understand the problem I am facing, could you help me?
UPDATE 1: If I extend the video duration to 4s, the shape position at 3s is the right one
UPDATE 2: I added -framerate 100 as option the logo.png input and fps=24 just after the scale filter. The problem is still present. I extracted every frame as png (as expected there are 72 frames) & 17 were generated between 2.2s & 3s.
UPDATE 3: The problem is resolved by settings a fps of 100. However the generated video file is too big. Is there any other way to get it to work at 24fps?
