scalpel ERROR: Couldn't measure size of image file

Good day team Sleuthkit, I can’t run scalpel in a backup.img (dd a external USB HDD 320GB) because it always “skips” on 83.1% mark with the following verbose stdout. It “drops” either in a live-usb Backbox Linux (scalpel 1.60-8) or frugal with persistence AntiX Linux (scalpel 1.60-6 and github build’s 2.1). I could run the same img with foremost which succeeded carving files. Please advise me if scalpel is OFF-TOPIC or whatever more appropriate routes I should follow to get the desired file recovery.