ereader-reencodelisted

# Re-encoding books for an E Ink reader ## The one thing to understand first **The bottleneck is not file size, it is decode cost per page.** These pull in opposite directions, and getting this backwards undoes the whole job. A source file is small on disk *because it pushes the work onto the reader*. An Internet Archive scan fits 5 megapixels into 17 KB — as JPEG 2000, decoded by wavelet transform, with a separate JBIG2 mask to decode and compose on top. The compression is spectacular; the price is paid on every page turn. Output files are therefore **often larger on disk and three to ten times cheaper to display**: baseline JPEG, sized to the panel, one greyscale channel where the book is monochrome, no mask. ⚠️ **Never "re-optimise" an output file to make it smaller.** That recreates the problem. ## Workflow 1. **Ask which device** if the user has not said. It changes the target size. Run `python scripts/reencode.py --list-devices` to show the profiles. 2. **Look at what was given.** Report the classification before converting, so the user can correct you — especially any file detected as `text`. 3. **Run the script**, one command per book when titles matter. 4. **Report** the before/after table and hand back the files. ```bash python scripts/reencode.py "book.pdf" --device era-color --out reencoded python scripts/reencode.py "book.pdf" --device inkpad-color-3 \ --title "Mon ballon" --author "Mario Ramos" --publisher "L'École des loisirs" ``` Requires **