ffmpeg halt when I turn video into image

My command is: ffmpeg -threads 1 -i http://illegal-video.nos.netease.com/hDHnMXpHywUcs2q7.mp4 -vf fps=1/5.0 C:\Users\Roomy\Desktop\test\image%d.jpg

but I got

And ffmpeg is halt when the error occurs.

Is that a bug?