You can link up to a thousand images at a time to your titles on the system. To do this, you will need to have your titles assigned to your account already (to check this, search or browse for the titles you want in My Books).
Images must be labelled by their ISBN-13, ISBN-10 or ISSN numbers, i.e. a 13, 10 or 8 digit number with no title names/characters. File type must be .jpg or .png. See full image specifications article here.
Example filenames: 9780000000001.jpg, 001222X7.png
Once you have made sure the filenames are correct and your titles are assigned to your account, log in and go to the Bulk Upload Images page, accessible from the Manage Titles page. From here, you can either drag the image files into the upload window (where it says 'Drag files here') or click 'Add Files' to browse for them.
Click 'Start Upload' to begin the upload. Once the loading bar indicates all files have uploaded (i.e. 342/342) the process is complete.