With C++ and QT, how do I display a 16-bit raw file as an image? -

-

i looking display heightmaps video game battlefield 2 images in application. new c++ , qt , might straight forward having trouble displaying grayscale 16-bit 1025x1025 2101250 bytes image. there no header file. need access displayed pixels (does not have pixel perfect precision) can point pixel , value.

what have tried

i have loaded binary data qbytearray qfile , have attempted use qimage::fromdata function make image making lot of mistakes , spending lot of time not getting far. hope posting here give me clue(s) need progress. here code:

void learningbinaryreader::setupreader() {     qdebug("attempting open file..");     qfile file("heightmapprimary.raw");     if (!file.open(qfile::readonly))     {         qdebug("could not open file");         return;     } else {         qdebug() << file.filename() << " opened";     }     qbytearray data = file.readall();     file.flush();     file.close();      qdebug() << data.count() << "bytes loaded."; }

from here @ loss of do. have read of qt documentation, being new need guide in right direction understand problem , solution.

please note pretty beginner don't discount easy solutions might not have thought of. using qt framework.

just guess. maybe try this?

#include <qcolor> ... qbytearray data=file.readall();  // create empty image of right size.  we'll use 32-bit rgb simplicity qimage img(1025,1025, qimage::format_rgb32);  // access image @ low level.  manual, 32-bit rgb image // vector of qrgb (which integer typedef) qrgb *pixels=reinterpret_cast<qrgb*>(img.bits());  // copy our image data in.  we'll assume 16-bit le format input data. // since have 8 bits of grayscale color resolution in 32-bit rgb, we'll // chop off significant 8 bits (the second byte of each pair) ,  // make pixel out of that.  if doesn't work, our assumption might off -- // perhaps assume 16-bit format.  in case we'd want first byte of each // pair. (size_t i=0;2*i<data.size();++i) {     uchar pixel_msb=data[2*i+1]; // or maybe try =data[2*i+0]     pixels[i]=qrgb(pixel_msb, pixel_msb, pixel_msb); }  // (do resulting 'img')

edit: oops, qimage::format_rgb32 instead of qimage::format_rgb


Comments

Post a Comment

Popular posts from this blog

c# - SVN Error : "svnadmin: E205000: Too many arguments" -

-
i trying reposotries using c# code process svncommand = null; var psi = new processstartinfo("svnadmin"); psi.redirectstandardoutput = true; psi.redirectstandarderror = true; psi.useshellexecute = false; psi.arguments= @"dump c:\repositories\myrepo > c:\temp\myrepodumpfile.dump"; using (svncommand = process.start(psi)) { var myoutput = svncommand.standardoutput; var myerror = svncommand.standarderror; debug.write("output :" + environment.newline + environment.newline + myoutput.readtoend() + environment.newline + "error :" + environment.newline + environment.newline + myerror.readtoend()); svncommand.close(); } when use dump command commandline svnadmin dump c:\repositories\myrepo > c:\temp\myrepodumpfile.dump it works fine when try ...
Read more

c# - Copy ObservableCollection to another ObservableCollection -

-
how copy observablecollection item observablecollection without reference of first collection? here observablecollection item value changes affecting both collections. code private observablecollection<ratemodel> _allmetalrate = new observablecollection<ratemodel>(); private observablecollection<ratemodel> _metalrateondate = new observablecollection<ratemodel>(); public observablecollection<ratemodel> allmetalrate { { return this._allmetalrate; } set { this._allmetalrate = value; notifypropertychanged("metalrate"); } } public observablecollection<ratemodel> metalrateondate { { return this._metalrateondate; } set { this._metalrateondate = value; notifypropertychanged("metalrateondate"); } } foreach (var item in metalrateondate) allmetalrate.add(item); what causing , how can solve it? you need clone object referenced item before it's a...
Read more

All overlapping substrings matching a java regex -

-
is there api method returns (possibly overlapping) substrings match regular expression? for example, have text string: string t = 04/31 412-555-1235; , , have pattern: pattern p = new pattern("\\d\\d+"); matches strings of 2 or more characters. the matches are: 04, 31, 412, 555, 1235. how overlapping matches? i want code return: 04, 31, 41, 412, 12, 55, 555, 55, 12, 123, 1235, 23, 235, 35. theoretically should possible -- there obvious o(n^2) algorithm enumerates , checks substrings against pattern. edit rather enumerating substrings, safer use region(int start, int end) method in matcher . checking pattern against separate, extracted substring might change result of match (e.g. if there non-capturing group or word boundary check @ start/end of pattern). edit 2 actually, it's unclear whether region() expect zero-width matches. specification vague, , experiments yield disappointing results. for example: string line = "xx90xx"; strin...
Read more