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+# Photocheck
+
+Check that you copied all your photos off that SD card.
+
+This tool is explicitly for the workflow of manually copying files from a single or few
+directories (e.g. an SD card) into multiple other directories (e.g. by date or by
+event). It verifies that all the files present in a source directory structure are
+present in a destination directory structure.
+
+## Status
+Very much half baked, but does what I need it to do
+
+## Safety
+This tool uses a (filename, filesize) pair. So, will protect you if your file was
+truncated for some reason, but not against file corruption due to dodgy SD card, cosmic
+rays etc. Doing this rather than comparing contents or hashes allows us to run very
+quickly over many files.
+
+
+## Usage
+`./photocheck path/to/source path/to/dest`