On Android 4 ICS (and possibly others), a giant thumbnail file may be created in your DCIM folder. This file can be several Gigabytes in size, depending on how many pictures you have. It is generated by the Android Gallery app.
- Quick and temporary solution- just delete any files/folders in your DCIM folder that start with .thumbnail
- Create a file named .nomedia in certain folders to prevent the gallery from scanning those folders. More info
- Delete the .thumbnail and replace is with an empty folder or empty file. More info
- A thumbnail deleter app developed by ppero196
The answer provided is definitely true and working but there seems to be a slight problem in the execution of it though. As for some Android devices that I have seen, most of them don’t seem to show the ” .thumbnail ” file when one wants to delete it. So one has to plug in to pc or laptop via a usb cable to delete it . Not only that the problem ends here, you got to remove the ” .thumbnail ” file here this way and eject your device and go on to phone storage in a file manager and create a ” .thumbnail ” file as soon as possible at least without opening the gallery. If you delay or open the gallery by any means, the ” .thumbnail ” file gets created again in the folder which once again I say, is invisible in some Android devices without connecting to pc/laptop.