Hi Daniel, [email protected] writes:
> Hello, > > I have been trying to get a device running for a few weeks now. After > failing to build a backend I decided to hack together my own LibUSB > driver for my unsupported A8 scanner, given my use case is pretty simple > I went in with a "how hard can it be?" attitude. > > Great success so far. Hasn't been easy but it hasn't been really that > bad. I have managed to ask my tiny A8 feed scanner to scan a 300dpi > colour image. I have been able to save the data to a file (about 8mb > worth) but that's where the fun ends. > > Can't seem to figure out how to get that raw data into a usable format. > 2 questions: > > 1. What format is that raw data likely to be? I naively expected it to > be png. Hmm, more likely to be "raw" data or JPEG. Save the image data you get to file as is and let the `file` command take a stab at it. It should recognize standard image file formats. If it's raw data, you want to note the image width, height and depth of your scan and try prepending a PNM header to the data you got. > 2. Does SANE have some code that handles that sort of conversion I could > have a look at? Looked around the internet and the SANE docs. Read some > things about frames, but couldn't find much else. If it's raw data, you can very likely just pass it to a SANE frontend as is (assuming 1, 8 or 16 bits per pixel and telling the fronted that). For JPEG, there are a number of backends that already handle that. Just run `git grep -l jpeg -- backend` to find them. For PNG, you may want to check the brand new escl backend. Hope this helps, -- Olaf Meeuwissen, LPIC-2 FSF Associate Member since 2004-01-27 GnuPG key: F84A2DD9/B3C0 2F47 EA19 64F4 9F13 F43E B8A4 A88A F84A 2DD9 Support Free Software https://my.fsf.org/donate Join the Free Software Foundation https://my.fsf.org/join
