Processing 1.0 - Processing Discourse - Fill array with images

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Fill array with images (Read 3385 times)

michael crane YaBB Newbies Offline Posts: 17	Fill array with images Jan 17^th, 2010, 7:25am to practice with processing I want to do that thing to make one image out of a sequence by taking a vertical strip from 1.jpg an adjacent strip from 2.jpg an adjacent strip from 3.jpg.. Etc so if I have a bunch of images in a folder how do I fill an array pic[1]..pic[2] with those images? Cheers Mick

Re: Fill array with images
Reply #1 - Jan 17^th, 2010, 8:37am

Here is some code I once used to load images from a folder. It only loads .jpg and .JPG files. (Leave out or change the check if you want to load other filetypes).

Files were located in a submap of the sketch folder called "pictures".

Code:


    //Read the pictures
    {     	
      students = new Vector();
      File f1 = new File(sketchPath + "/pictures") ;

      File[] files = f1.listFiles();

      for (int i = 0 ; i < files.length ; i++ ) {
        if(files[i].toString().indexOf(".jpg") != -1 || files[i].toString().indexOf(".JPG") != -1) 
        {
          students.add(loadImage(files[i].getAbsolutePath()));
        }
      }
    }

michael crane YaBB Newbies Offline Posts: 17	Re: Fill array with images Reply #2 - Jan 17^th, 2010, 8:57am Many thanks. I guessed it would be something with strings but my brain cell is not working so well these days. Cheers Mick

michael crane YaBB Newbies Offline Posts: 17	Re: Fill array with images Reply #3 - Jan 17^th, 2010, 9:55am I'm sorry, should that work as is? I get "syntax error, maybe missing right parenthesis" on line if(files[i] to String().indexOf..... And I can't see why my router has packed up so I can't paste ( using phone) Mick

michael crane YaBB Newbies Offline Posts: 17	Re: Fill array with images Reply #4 - Jan 17^th, 2010, 10:11am Ok I found typo but still says syntax error

michael crane YaBB Newbies Offline Posts: 17	Re: Fill array with images Reply #5 - Jan 18^th, 2010, 6:20am I don't understand if I copy paste your code it runs but if I try to "tidy" it with some carriage returns it complains "cannot find anything named " students"" I thought spaces made no difference ?

michael crane YaBB Newbies Offline Posts: 17	Re: Fill array with images Reply #6 - Jan 18^th, 2010, 6:28am Doh if I paste it it is one line which is entirely commented out

PhiLho

Re: Fill array with images
Reply #7 - Jan 18^th, 2010, 6:42am

You are not supposed to use the code as is, but to adapt it (I doubt you have students in your code...).
Here is something more adapted to your requirements:
Code:

File picturesPath = sketchFile("pictures"); // Supposes you have a "pictures" folder in your sketch folder
File[] files = picturesPath.listFiles(); // Get a list of files
PImage[] images = new PImage[files.length];
int imageCount = 0;
for (int i = 0; i < files.length; i++) {
    String fileName = files[i].getName().toLowerCase();
    if (fileName.endsWith(".jpg") || fileName.endsWith(".png")) {
	  images[imageCount++] = loadImage(files[i].getAbsolutePath());
    }
}

(untested!)
At the end of the loop, imageCount holds the number of loaded images, can be smaller than files.length.

« Last Edit: Jan 20^th, 2010, 4:30am by PhiLho »

michael crane YaBB Newbies Offline Posts: 17	Re: Fill array with images Reply #8 - Jan 20^th, 2010, 4:22am Hi, I get "cannot convert from PImage[] to PImage" I've not done much coding and I just started with processing. I thought I would start by filling an array with the names of the pictures in the directory. If it just worked I suppose I wouldn't be Reading so much. Mick

PhiLho

Re: Fill array with images
Reply #9 - Jan 20^th, 2010, 4:33am

Sorry, I made a typo, should have been PImage[] images = new PImage[files.length]; (also fixed above).
The files variable above is just what you want: an array with a list of files. If you prefer to have a list of file names, use String[] fileNames = picturesPath.list();
The additional loop is used to filter out non-image files, you can drop it if you are sure you will put only images in this directory.

michael crane YaBB Newbies Offline Posts: 17	Re: Fill array with images Reply #10 - Jan 20^th, 2010, 10:44am Thanks for your help. I'm getting the hang of it. How do I get pixels 100 to 199 or 200 to 299 from a 100x100 image using pixels[] regards Mick

knutEinar

Re: Fill array with images
Reply #11 - Jan 20^th, 2010, 2:14pm

michael crane wrote on Jan 20^th, 2010, 10:44am:

Thanks for your help. I'm getting the hang of it.
How do I get pixels 100 to 199 or 200 to 299 from a 100x100 image using pixels[]
regards
Mick

I would start with the example shown in the Reference:
Code:

int halfImage = width*height/2;
PImage myImage = loadImage("topanga.jpg");
image(myImage, 0, 0);

loadPixels();
for (int i = 0; i < halfImage; i++) {
  pixels[i+halfImage] = pixels[i];
}
updatePixels();

and tweak that to your advantage.
I guess you would need to have a loop for every image that you load, that runs through the width (or height), something like:
Code:

j++; // j would be equal to the current image number in the series of images, and thus also representing a line in your new image
for (int i = 0; i < myImage.width; i++) {
  newImage.pixels[j*myImage.width+i] = loadedImage.pixels[j*myImage.width+i];
}

michael crane YaBB Newbies Offline Posts: 17	Re: Fill array with images Reply #12 - Jan 21^st, 2010, 12:30am Thanks. I realize now that the pixel[] array addresses one pixel at a time. I thought it might be able to addresses a block. It's clearer. Regards Mick

PhiLho YaBB Moderator Offline Posts: 4190 Near Paris (France)	Re: Fill array with images Reply #13 - Jan 21^st, 2010, 12:53am You can use copy() to handle blocks of pixels in a friendly/intuitive way.

michael crane

Re: Fill array with images
Reply #14 - Jan 21^st, 2010, 2:46am

would copy() be quicker
this is what I have so far from the suggestions.
Code:

 size(533, 400);
File path= sketchFile("pictures");
File[] files= path.listFiles();
PImage[] images = new PImage[files.length];
PImage NewImage=createImage(533,400,RGB);
images[0] = loadImage(files[0].getAbsolutePath());
int count = images[0].width*images[0].height/(files.length);//pixels per image strip
//println(count);
for (int i=0;i<files.length;i++)
{
images[i] = loadImage(files[i].getAbsolutePath());
print(i+ " of "+( files.length)+"; ");
for (int j=0;j<count;j++)
{
loadPixels();
NewImage.pixels[i*count+j]=images[i].pixels[i*count+j];
updatePixels();
}
}
image(NewImage,0,0);

Does that look right ?
it seems slow to make a new image with 10 images and I was hoping to use a thousand. is there a way
to speeds things up ?
cheers

Mick

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