Attempt to unlock mutex that was not locked in melodic

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i was using ubuntu 16.04 and then upgraded to 18.04 hence i had to go with melodic but im not able to run the launch file properly its popping the above mentioned error how to solve it .please do help i am new to ros envirnoment .thanks in advance!

(image_out:1938): GLib-GObject-CRITICAL **: 18:11:16.691: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
[ INFO] [1556887276.750520962]: Loading file whycon_transforms.yml
[ WARN] [1556887276.751550661]: Could not load "whycon_transforms.yml"

(image_out:1938): GLib-GObject-CRITICAL **: 18:11:16.780: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
Attempt to unlock mutex that was not locked
[whycon_display/image_view-4] process has died [pid 1938, exit code -6, cmd /opt/ros/melodic/lib/image_view/image_view image:=/whycon/image_out __name:=image_view __log:=/home/cry2ra5y/.ros/log/a6f514ca-6d9f-11e9-98a9-680715255a44/whycon_display-image_view-4.log].
log file: /home/cry2ra5y/.ros/log/a6f514ca-6d9f-11e9-98a9-680715255a44/whycon_display-image_view-4*.log