cocoa - Methods to render a PDF into a very high resolution NSImage bitmap file -

-

i have render pdf high resolution image (say , on 100,000 * 80,000 pixels).

i managed without going out of ram splitting render several slices , rendering each 1 using nsoperationqueue, drawing nsimage pdf representation new nsimage using drawinrect:fromrect:operation:fraction: , saving tiffrepresentation file.

all , multicore , fast , i'm happy. anyway i'd need join slices again after rendered them, obtain single tiff file.

i try merge files using nsinputstream , nsoutputstream since each file complete tiff representation, merging raw bytes result in unreadable picture file. there way merge image files without loading them ram, i.e. without using nsimage methods?

otherwise save raw pixel bytes instead of tiff representations , join them nsinputstream/nsoutputstream, how transform whole bytes file recognizable tiff without, again, loading huge thing ram?

this technique won't work extreme demands (see end of message more on that), other people higher res image pdf screenshot or snapshot acrobat tool. it's not particularly elegant, gets job done.

instructions based on acrobat 9 reader (earlier , later versions should work long have snapshot/"marquee select" tool) on windows xp. imagine applies on other platforms run adobe reader. (now think there alternative pdf display software can without tricks. maybe based on ghostscript?) in case, know works:

  1. zoom in on pdf until image on monitor has pixel resolution you're looking for. if you're trying capture image more pixels have on monitor (which reason use technique), be seeing portion of image on screen.
  2. scroll needed find corner of pdf want capture.
  3. select snapshot/"marquee select" tool.
  4. click corner, hold mouse button down (drag-select) , move mouse opposite corner of window.
  5. the screen start auto scrolling towards opposite corner of image. may take while, there.
  6. when opposite edge, take finger off mouse, , should have high-res image in clipboard.

now, depending on "size" of initial image (acrobat zoom 6400% of original size based on dpi information in pdf), technique theoretically allow 100k x 80k pixels. falls apart of today's pcs you'd need enough ram hold 22gb of image data in copy buffer...


Comments

Post a Comment

Popular posts from this blog

c++ - Convert big endian to little endian when reading from a binary file -

-
this question has answer here: how convert between big-endian , little-endian values in c++? 28 answers i've been looking around how convert big-endian little-endians. didn't find solve problem. seem there's many way can conversion. anyway following code works ok in big-endian system. how should write conversion function work on little-endian system well? this homework, since systems @ school running big-endian system. it's got curious , wanted make work on home computer also #include <iostream> #include <fstream> using namespace std; int main() { ifstream file; file.open("file.bin", ios::in | ios::binary); if(!file) cerr << "not able read" << endl; else { cout << "opened" << endl; int i_var; double d_var; while(!file.eof()) {...
Read more

C#: Application without a window or taskbar item (background app) that can still use Console.WriteLine() -

-
i'm trying create application adheres following: no taskbar no console or form window can utilize console.writeline() . (i.e. if executes app command prompt write console.) the problem if create windows form (or wpf) application can have there no taskbar, console or window show up, console.writeline() nothing. if create console app, writes console, can't figure out how hide (and if did hide it, write command prompt window?)... how do this? just create standard console application. callers responsibility hide window caused program (from how run c# console application console hidden ): system.diagnostics.processstartinfo start = new system.diagnostics.processstartinfo(); start.filename = dir + @"\myprocesstostart.exe"; start.windowstyle = system.diagnostics.processwindowstyle.hidden;
Read more

unicode - Are email addresses allowed to contain non-alphanumeric characters? -

-
i'm building website using `django. website have significant users non-english speaking countries. i want know if there technical restrictions on types of characters email address contain. are email addresses allowed contain english alphabets, numbers, "_", "@" , "."? are allowed contain non-english alphabets "é" or "ü"? are allowed contain chinese or japanese or other unicode characters? email address consists of 2 parts local before @ , domain goes after. rules these parts different: for local part can use ascii: latin letters - z - z digits 0 - 9 special characters !#$%&'*+-/=?^_`{|}~ dot ., not first or last, , not in sequence space , "(),:;<>@[] characters allowed restrictions (they allowed inside quoted string, backslash or double-quote must preceded backslash) plus since 2012 can use international characters above u+007f , encoded as utf-8 . domain part more res...
Read more