4 ms·

5 TB on paper needs to much room to store.

by js4all 16y ago

barrkel 16y ago
It depends on who's doing the storing. A4 page, which has 210x297mm, say a border of 10mm all around non-printable area, gives 190x277. Say we print at a resolution of 0.5mm, and in 16 shades, so we get 4x4 = 16 bits per mm, or 2 bytes. That gives 105,260 bytes per page. Probably we can squeeze more bytes in than this, but let's allocate those to redundancy and error correcting codes. So for 5TB (in hard drive size, 5e12) would take about 23.75 million sheets of paper printed on both sides. At 5g per sheet, that's about 119 metric tons. 1 ream (500 pages) of the 75g/m^2 A4 paper I have beside my printer here is about 50mm thick. Say 215x305x55mm including some slack for packaging, is a little over 3.6 litres in volume; total volume for 23.75 million sheets is 171,285 litres, or 171.285 cubic metres. A room with a ceiling height of 3 metres would need to be only 8 meters on each side to store this. Of course, the room shouldn't have any windows and should be at the appropriate humidity, etc. The cost of the paper, assuming $5 per 500 pages, is less than a quarter of a million. Much more forbidding is the labour and temporary acquisition of printers required to transcribe the data to paper. A good printer @50ppm would take nearly 2 years, assuming zero downtime and very quick paper and toner changes. To do it in more reasonable time and with more reliability, you'd want a bunch more printers; and of course, you'd need to hire the people to do the work of shuffling paper and carting it around, but I'd bet you could probably do it for less than the cost of the paper, particularly if you did it in a cheap labour country.
- staunch 16y ago
  This guy claims 200 kB per A4 page http://ronja.twibright.com/optar/ http://ronja.twibright.com/optar/
  - fhars 16y ago
    Which gives you 125 tons for 5TB on 80g/m² paper single sided, which gives you about the same cost as the 119 tons double sided in the GP, but without paper jams in the duplexer unit.
    - barrkel 16y ago
      The estimated error rate is however about 1 in 100,000 pages, which isn't quite good enough. Probably a slightly better code can be used with a small amount of inflation; even something like RAID-5 except over pages (i.e. parity pages) would do.
- fxj 16y ago
  190mm * 277mm = 52630 mm2 size of one pixel: 0.5mm * 0.5mm= 0.25 mm2 1 page can then hold: 52630/0.25 = 210520 pixel 1 pixel is 2 byte thus 1 page is 421040 byte is about 0.5 MB/page (or 1 MB if you print double sided) 5 TB= 5000 GB = 5,000,000 MB = 5 Million pages this is 5000 books with 1000 pages each.
  - barrkel 16y ago
    Note that you have increased the density of information from my calculation of 16 shades per pixel of 0.5mm x 0.5mm, giving 4 bits per pixel (i.e. half a byte, or one nibble, per pixel), so 16 bits per 1mm^2, and thus 2 bytes per square millimeter. I intentionally chose a pretty big pixel for redundancy reasons rather than trying to be clever and working out a code etc., but the link in the reply to my post looks more worked out.

5 TB on paper needs to much room to store.

by js4all 16y ago

5 TB on paper needs to much room to store.

It depends on who's doing the storing. A4 page, which has 210x297mm, say a border of 10mm all around non-printable area, gives 190x277. Say we print at a resolution of 0.5mm, and in 16 shades, so we get 4x4 = 16 bits per mm, or 2 bytes. That gives 105,260 bytes per page. Probably we can squeeze more bytes in than this, but let's allocate those to redundancy and error correcting codes. So for 5TB (in hard drive size, 5e12) would take about 23.75 million sheets of paper printed on both sides. At 5g per sheet, that's about 119 metric tons. 1 ream (500 pages) of the 75g/m^2 A4 paper I have beside my printer here is about 50mm thick. Say 215x305x55mm including some slack for packaging, is a little over 3.6 litres in volume; total volume for 23.75 million sheets is 171,285 litres, or 171.285 cubic metres. A room with a ceiling height of 3 metres would need to be only 8 meters on each side to store this. Of course, the room shouldn't have any windows and should be at the appropriate humidity, etc. The cost of the paper, assuming $5 per 500 pages, is less than a quarter of a million. Much more forbidding is the labour and temporary acquisition of printers required to transcribe the data to paper. A good printer @50ppm would take nearly 2 years, assuming zero downtime and very quick paper and toner changes. To do it in more reasonable time and with more reliability, you'd want a bunch more printers; and of course, you'd need to hire the people to do the work of shuffling paper and carting it around, but I'd bet you could probably do it for less than the cost of the paper, particularly if you did it in a cheap labour country.

staunch 16y ago
This guy claims 200 kB per A4 page http://ronja.twibright.com/optar/ http://ronja.twibright.com/optar/
- fhars 16y ago
  Which gives you 125 tons for 5TB on 80g/m² paper single sided, which gives you about the same cost as the 119 tons double sided in the GP, but without paper jams in the duplexer unit.
  - barrkel 16y ago
    The estimated error rate is however about 1 in 100,000 pages, which isn't quite good enough. Probably a slightly better code can be used with a small amount of inflation; even something like RAID-5 except over pages (i.e. parity pages) would do.
fxj 16y ago
190mm * 277mm = 52630 mm2 size of one pixel: 0.5mm * 0.5mm= 0.25 mm2 1 page can then hold: 52630/0.25 = 210520 pixel 1 pixel is 2 byte thus 1 page is 421040 byte is about 0.5 MB/page (or 1 MB if you print double sided) 5 TB= 5000 GB = 5,000,000 MB = 5 Million pages this is 5000 books with 1000 pages each.
- barrkel 16y ago
  Note that you have increased the density of information from my calculation of 16 shades per pixel of 0.5mm x 0.5mm, giving 4 bits per pixel (i.e. half a byte, or one nibble, per pixel), so 16 bits per 1mm^2, and thus 2 bytes per square millimeter. I intentionally chose a pretty big pixel for redundancy reasons rather than trying to be clever and working out a code etc., but the link in the reply to my post looks more worked out.