save file instead of show image in windows

[MeepoAII]

I notice your comment on the ‘out_file‘ parameter of the show_result function in inference.py: If out_file is specified, the visualization result will be written to the out file instead of shown in a window, but actually it is shown in windows. (and because I run my python in no gui environment, even though i specify the out_file, it shows cannot connect to X server, which may be confused to somebody new to this)
So, I add a if statement before show image.

[hellock]

Thanks for the fix.

[OpenMMLab-Assistant-004]

Hi @MeepoAII ！First of all, we want to express our gratitude for your significant PR in the mmdetection project. Your contribution is highly appreciated, and we are grateful for your efforts in helping improve this open-source project during your personal time. We believe that many developers will benefit from your PR.

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[OpenMMLab-Assistant-004]

Hi @MeepoAII ！First of all, we want to express our gratitude for your significant PR in the mmdetection project. Your contribution is highly appreciated, and we are grateful for your efforts in helping improve this open-source project during your personal time. We believe that many developers will benefit from your PR.

We would also like to invite you to join our Special Interest Group (SIG) private channel on Discord, where you can share your experiences, ideas, and build connections with like-minded peers. To join the SIG channel, simply message moderator— OpenMMLab on Discord or briefly share your open-source contributions in the #introductions channel and we will assist you. Look forward to seeing you there! Join us ：https://discord.gg/raweFPmdzG

If you have WeChat，welcome to join our community on WeChat. You can add our assistant ：openmmlabwx. Please add "mmsig + Github ID" as a remark when adding friends：）
Thank you again for your contribution❤