You can already do this by editing JPEGView.ini and adding an entry to "User commands":
UserCmd1="KeyCode: P Cmd: '"C:\Program Files\Adobe\Adobe Photoshop CC 2015\Photoshop.exe" %filename%' Menuitem: 'Photoshop CC 2015' HelpText: 'P\tOpen in Photoshop'"
This will open the current image on Photoshop CC 2015 when pressing "P" key..
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You can already do this by editing JPEGView.ini and adding an entry to "User commands":
UserCmd1="KeyCode: P Cmd: '"C:\Program Files\Adobe\Adobe Photoshop CC 2015\Photoshop.exe" %filename%' Menuitem: 'Photoshop CC 2015' HelpText: 'P\tOpen in Photoshop'"
This will open the current image on Photoshop CC 2015 when pressing "P" key..
Easier way:
right-click on image
Settings/Admin (at bottom of list)
Manage 'Open image with' menu...
Then add new entry with keyboard shortcut to your liking.