Do you think this is possible to do? but i think possible,there are various lot of recovery tools in the internet to download,but all of them are not surely work 100% like you are expected.but there is a recovery tool name recuva,working perfectly as you expected. Download recuva here
Okey now we can see the step by steps to start the process.
Step1)-insert the pen drive in to the usb port.wait for some moment to identify .after that right click on the pen drive icon in the computer and scan for recovery of bad sector and automatically fix system errors
Note- above step is important to recover correctly
Step2)- install the recuva recovery software before you downloaded.
Step3)- open the tool by clicking its icon on the desktop. Program will open up.
Step4)- if you recover images tick the dot on pictures ( removable disk /memory device ) and then select deep scan
Note- selecting deep scan is important.
Step5)-click scan .scanning process will start up wait for some hours or minutes .that depending on your pen drive volume.
Step6)-now picture list show up ,you must select the picture you want. click recover and select the location to put the pictures
That’s all enjoy