The 10 values are the paddings!

Top left

ffmpeg –i source.avi -vf "movie=watermark.png [watermark]; [in][watermark] overlay=10:10 [out]" output.flv

Top right

ffmpeg –i source.avi -vf "movie=watermark.png [watermark]; [in][watermark] overlay=main_w-overlay_w-10:10 [out]" output.flv

Bottom left

ffmpeg –i source.avi -vf "movie=watermark.png [watermark]; [in][watermark] overlay=10:main_h-overlay_h-10 [out]" output.flv

Bottom right

ffmpeg –i source.avi -vf "movie=watermark.png [watermark]; [in][watermark] overlay=main_w-overlay_w-10:main_h-overlay_h-10 [out]" output.flv

Center?

ffmpeg –i source.avi -vf “movie=watermark.png [watermark]; [in][watermark] overlay=main_w/2-overlay_w/2:main_h/2-overlay_h/2 [out]” output.flv

How can I extract the first frame from a movie AND overlay a watermark on it at the same time?

ffmpeg -i movie.mp4 -i image.png

-filter_complex

"[0]scale=W:H:force_original_aspect_ratio=decrease[v];

[v][1]overlay=(W-w)/2:(H-h)/2"

-vframes 1  output.jpg