Testing

Testing reliability

dd if=/dev/zero over netcat
536870912 bytes (537 MB) copied, 135.758 s, 4.0 Mb/s
100mbit wired connection

previews: downscale jpeg 4320x3240 -> 500x375:
full image: 1.4Mb*2=2.8Mb wired network transfer at 4Mb/s~=0.7s
downscaled preview: 50k wired network transfer neglegible= ~0.7s win
pil, imagemagick: 5.2s
epeg-cffi: 0.7s
net effect to pc on wired LAN neutral (but faster rendering!)
positive performance effect to tablet/phone/... or over wifi
rotation:
jpegtran does lossless jpeg rotation (fast, without decoding/reencoding)
cropping:
jpegtran (old python wrapper) does lossless jpeg cropping (fast along DCT boxes, without decoding/reencoding)
deskewing:
It probably makes sense to do this before feeding to tesseract since it would need to happen twice otherwise...
unpaper
leptonica
imagemagick
pamtilt (netpbm)
scantailor-cli
get public domain books
scan and publish (github? ...)
thumbnails for browser preview:
epeg
avoid temporary files (disk i/o!)
bitonalisation (color -> b/w): unpaper,