Find Position in a Film/Video by a Frame
Try the command:

ffmpeg -i in.mp4 -loop 1 -i croppedframe.jpg -an -filter_complex "[0]crop=w:h:x:y[a];[1][a]blend=difference,blackframe=90:32" -f null - 


This will match a movie frame if at least 90% of the pixels have a difference in value of less than 32 with the image. Any such matching frames will have their timestamps shown