unable to view image in web mjpeg_server

edit

I have installed and run the mjpeg_server in my pi 4b and ubuntu 18 machie. in pi i am using image_transport node to publish image. after that i ran mjpeg_server node in pi. But when i try to view the image in web i can't access it. When i run the mjpeg_server node in ubuntu machine i can easily access the image with url:

http://localhost:11311/stream?topic=/camera/image

But similary when i try to access the image topic after running the mjpeg server in pi with url:

http://192.168.4.1:11311/stream?topic=/camera/image

i'm not able to access the image.

Wht is the problem here.