Memory Problems during Image Operations

[georg.viehoever]

Juan,

I am currently trying to write a script that does a number of image operations such as assign(), cropTo(), apply(...,add). According to PI, the images have the following characteristics:
- Canon 40D RAWs
- width/height: 3908/2602
- Channels: 3
- Datatype: i16
- size 58 MBytes (also matches the observations in the Windows task managers)

The memory consumption for the script editor or the PJSR compile&run, script GUI etc. seem to be neglidgible, but when the script executes, memory consuption explodes to 500 MBytes, and consequenty, PI gives up:

Code: [Select]

CcdParamsEngine.doFlat() entry
CcdParamsEngine.doImages() entry
CcdParamsEngine.doImages() image1.width, image1.height=3908,2602
CcdParamsEngine.doImages() image2.width, image2.height=3908,2602
CcdParamsEngine.doImages() sumImage.width, sumImage.height=0,0
CcdParamsEngine.doImages() sumImage.width, sumImage.height=0,0
CcdParamsEngine.computeTargetRect(),lengthFactor=0.1
CcdParamsEngine.computeTargetRect(),x0,x1,y0,y1=1758.6,2149.4,1170.9,1431.1000000000001
CcdParamsEngine.doImages() assign(Image1)
CcdParamsEngine.doImages() cropTo()1
CcdParamsEngine.doImages() assign(Image2)
CcdParamsEngine.doImages() cropTo()2
CcdParamsEngine.doImages() assign(cropped1)1
Basic CCD Params Script done
*** Error [000]: C:/PCLGeorg/scripts/BasicCameraParameters.js, line 251: out of memory

Could you have  a look at the code snippet attached below, to see what is going wrong there. What I am trying to do is to cut 10% of the central image region, and later do some statistical operations on that.

Thanks!

Georg

Code: [Select]

  this.computeTargetRect=function(image, lengthFactor){
      var width=image.width;
      var height=image.height;
      var newWidth=width*lengthFactor;
      var newHeight=height*lengthFactor;
      var targetRect=new Rect(newWidth,newHeight);
      targetRect.moveTo((width-newWidth)/2,(height-newHeight)/2);
      if ( DEBUGGING_MODE_ON ){
         console.writeln("CcdParamsEngine.computeTargetRect(),lengthFactor=",lengthFactor);
         console.writeln("CcdParamsEngine.computeTargetRect(),x0,x1,y0,y1=",
                           targetRect.x0,",",targetRect.x1,",",targetRect.y0,",",targetRect.y1);

      }  // if debugging

      return targetRect;
   }  //computeTargetRect()


   //compute derived images sumImage, diffImage
   this.doImages=function(image1, image2, lengthFactor, sumImage, diffImage){
      if ( DEBUGGING_MODE_ON ){
         console.writeln("CcdParamsEngine.doImages() entry");
         console.writeln("CcdParamsEngine.doImages() image1.width, image1.height=",image1.width,",",image1.height);
         console.writeln("CcdParamsEngine.doImages() image2.width, image2.height=",image2.width,",",image2.height);
         console.writeln("CcdParamsEngine.doImages() sumImage.width, sumImage.height=",sumImage.width,",",sumImage.height);
         console.writeln("CcdParamsEngine.doImages() sumImage.width, sumImage.height=",diffImage.width,",",diffImage.height);
      }  // if debugging
      var targetRect=this.computeTargetRect(image1,lengthFactor);
      var cropped1=new Image();
      cropped1.resetSelections();
      if ( DEBUGGING_MODE_ON ){
         console.writeln("CcdParamsEngine.doImages() assign(Image1)");
      }  // if debugging
      cropped1.assign(image1);
      if ( DEBUGGING_MODE_ON ){
         console.writeln("CcdParamsEngine.doImages() cropTo()1");
      }  // if debugging
      cropped1.cropTo(targetRect);
      var cropped2=new Image();
      if ( DEBUGGING_MODE_ON ){
         console.writeln("CcdParamsEngine.doImages() assign(Image2)");
      }  // if debugging
      cropped2.assign(image2);
      cropped2.resetSelections();
      cropped2.cropTo(targetRect);
      if ( DEBUGGING_MODE_ON ){
         console.writeln("CcdParamsEngine.doImages() cropTo()2");
      }  // if debugging
      if ( DEBUGGING_MODE_ON ){
         console.writeln("CcdParamsEngine.doImages() assign(cropped1)1");
      }  // if debugging
      sumImage.assign(cropped1);
      if ( DEBUGGING_MODE_ON ){
         console.writeln("CcdParamsEngine.doImages() apply(Add)");
      }  // if debugging
...


[Juan Conejero]

Hi Georg,

I have reproduced what you're trying to do in a simpler test script:

Code: [Select]

#include <pjsr/UndoFlag.jsh>

function MyTestThing()
{
   this.computeTargetRect = function( image, lengthFactor )
   {
      var k0 = (1 - lengthFactor)/2;
      var k1 = (1 + lengthFactor)/2;
      return new Rect( Math.round( image.width*k0 ),
                       Math.round( image.height*k0 ),
                       Math.round( image.width*k1 ),
                       Math.round( image.height*k1 ) );
   };

   this.doImages = function( image1, image2, lengthFactor )
   {
      // Cropping rectangle
   
      var targetRect = this.computeTargetRect( image1, lengthFactor );

      console.writeln( targetRect );

      // Cropped images

      var cropped1 = new Image( targetRect.width, targetRect.height, image1.numberOfChannels, image1.colorSpace );
      image1.selectedRect = targetRect;
      cropped1.apply( image1 );

      var cropped2 = new Image( targetRect.width, targetRect.height, image2.numberOfChannels, image2.colorSpace );
      image2.selectedRect = targetRect;
      cropped2.apply( image2 );

      // Show the cropped images

      var w1 = new ImageWindow( 1, 1 );
      w1.mainView.beginProcess( UndoFlag_NoSwapFile );
      w1.mainView.image.assign( cropped1 );
      w1.mainView.endProcess();
      w1.show();
      w1.zoomToOptimalFit();

      var w2 = new ImageWindow( 1, 1 );
      w2.mainView.beginProcess( UndoFlag_NoSwapFile );
      w2.mainView.image.assign( cropped2 );
      w2.mainView.endProcess();
      w2.show();
      w2.zoomToOptimalFit();
   };
}

var test = new MyTestThing;
test.doImages( ImageWindow.activeWindow.mainView.image,
               ImageWindow.activeWindow.mainView.image,
               0.5 );
As far as I can tell, the code above works fine. Note that you don't need to create a large image and then crop it. You can create a new image with the required dimensions and use image.selectedRect and Image.apply() to copy the desired region of the source image.

I don't know why your code is eating 500 MB. It is most likely a garbage collection issue, as happens frequently. I'd need to see your exact code to say something more specific, but have you tried putting some calls to gc() within your code?

[georg.viehoever]

Juan,

thanks for the code snippet. Replacing the relevant section of the my code with your procedure resolved the problem. I guess, the issue is somewhere in the cropTo(), which is the main difference between our 2 codes.

For the moment: issue closed (but keep in mind that there is something there...).

Georg