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One thought experiment that blew my mind even with the first generation of solid state digital storage. Imagine an uncompressed image large enough to fill the
by afandian 8y ago
One thought experiment that blew my mind even with the first generation of solid state digital storage.
Imagine an uncompressed image large enough to fill the card, at the size where you can make out every pixel, like 1mm pitch. Then imagine how small each pixel would be if you shrank it down to the size of the chip.
For 1 bit monochrome, 1TB is 2828427 x 2828427. At 1mm pitch, that's is 3 square miles. Imagine shrinking that down to 5mm.
(Edit in response to replies. This example is purposefully simplistic to demonstrate the point about shrinking pixels. A real photo wouldn't be monochrome, or 1-bit depth, or have a dot pitch of 1mm, or be uncompressed, or, for that matter, be 3 square miles big. I mean, who has that much ink?)
Edit 2: For a 2MB Compact Flash card from 1990s the equivalent is 16 square metres. That's still a lot of pixels to squeeze into such a tiny package.
- frabert 8y agoJust an observation: 1mm pitch is awful.
- rpeden 8y agoAlways? If I'm standing 10 metres away, I don't think it would be too bad. Even at 1 metre away it would be fine. With images as large as the OP is talking about, at typical viewing distances pitch substantially larger than 1mm would be just fine.
- afandian 8y agoAwful for what? When intuitively visualising the number of pixels in a terrabyte I think it's quite good.
- Dylan16807 8y agoWhen you're trying to leverage your intuitive understanding of photos, using such a low DPI will screw up that intuition and damage the accuracy. 1mm black and white is basically a QR code. I prefer to visualize things at a reasonable density. Using boring software and a boring printer, adding in redundancy and still using very visible dots[1], you can fit over 7000 bits per square cm instead of 100. That old 2MB card turns out to only be worth 4 sheets of paper. 1TB remains enormous, but going from 3 square miles down to .1 square kilometers helps to bring things closer to understandable. With this new density it's 25 acres or 17 football fields. Considering the flash layers is also useful to my intuition. That old CF card is four pieces of paper next to each other. This new card is a box 32 meters / 105 feet on each side, filled edge to edge with densely printed dots on paper stacked 96 sheets deep. I can actually visualize that room / yard. I can visualize the dots on a sheet of paper. I cannot visualize a square mile at human scale. [1] http://www.extremetech.com/wp-content/uploads/2012/08/extremetech-page-paperback-gif.gif http://www.extremetech.com/wp-content/uploads/2012/08/extrem...
- afandian 8y agoI was thinking purely about the physical size of a single bit. I feel like I can personally interact with a 1mm object. Anything smaller gets in the way of the physical intuition. I wasn't actually thinking about photos at all. Anyway, thanks for your perspective! I think the conclusion is the same -- we've come a long way from the internal combution engine.
- mark-r 8y agoYes, 0.1mm would be much better, that's 254 DPI. You'd also want 24 bits (3 bytes) per pixel instead of 1 bit. That gives you 0.43x0.43 miles, which is still mighty impressive.
- batbomb 8y agoOr head towards 72 DPI and get document quality resolution over a square mile.
- novaleaf 8y agoa follow up thought experiment: how long to walk that distance, VS how long to read the image from the SD card...... answer: walking the perimeter (aprox 2 miles): aprox 30min reading 1tb (assuming sustained speed of 20mb/sec): 14.5hrs next: consider WRITE speed...
- tandr 8y ago> Of the two cards, Western Digital is claiming a performance advantage by citing up to 160MB/s read speed so, 1h 44 minutes, which is not that bad
- novaleaf 8y agoThat is assuredly their best-case-scenario "burst" speed. The sd cards I have always list some performance like "up to 80mb/sec" but never seem to get close in reality.
- deleted 8y ago[deleted]
- 7952 8y agoI have some TIF files that are about that size uncompressed. They are 50cm resolution lidar images of England.
- cma 8y agoTo visualize chip density my go-to used to be thread count on bedding sheets. For 400 thread count sheets (which means 200 widthwise, 200 lengthwise threads per square inch), that 1990s compact flash card would be about 1.6ft squared. You could sort of imagine a tape-out of that complexity being shrunk down through projection. Now at these densities it is no longer holding up well. 1TB would be a sheet that was about 1100ft x 1100ft. The tape-out itself seems like it would have to be sized to already be the after-shrunk-down version of 1990's tape-outs.
- KozmoNau7 8y agoWe'll soon be talking about terrabytes, not terabytes :-)