Dearest Monks ...

I have been staring at this simple code now for hours to no avail. 

#!/usr/bin/perl 

use GD;
use CGI::Carp qw/ fatalsToBrowser /;
use warnings;

print "Content-type: text/html\n\n";

#Master Image
$code_image_file = '8_QB.jpg';

$file_code = "/BigExp/exp8/$code_image_file";

$image_code = GD::Image->newFromJpeg($file_code);

#Creation of smaller image to be used as 
#repository for contents of smaller image contained
#within Master image
$ESP_code = new GD::Image(200,200);

#Loop through specific pixel block in Master Image 
for ($y=0; $y<200; $y++) {
    
    for ($x=0;$x<200;$x++) {
            
        #Get pixel intensity data
        $index = $image_code->getPixel($x,$y);
        ($red,$green,$blue) = $image_code->rgb($index);
        
        $color = $ESP_code->colorAllocate($red,$green,$blue);
        
        $ESP_code->setPixel($x,$y,$color)        
        
    } # End of Row cycle

} ## End of Column cycle

# Convert the image to JPEG and write it to a file.
$image =  $ESP_code->jpeg([50]);

binmode STDOUT;

#Write to file

open ESP_IMAGE, ">image.jpg";
print ESP_IMAGE $image;
close ESP_IMAGE;

print "<img src='image.jpg'>";

[download]

This is sampling each pixel in the master image at the looped through x,y coordinates and (I had hoped) reassembling an abbreviated version of the image.

It works fine when either:

(1) I specifically set the color allocate value (say at 0,0,0 or 60,70,5, etc), or

(2) I convert the Master file back to a jpeg (i.e., I get the original image).

But it doesn't work (i.e., it "displays" a white image the size of my desired image - 200x200 in this case) when I have the dynamic r,g,b color change.

I have printed out the r,g,b values and confirmed a dynamic change in these values as they step through the image.

The first pixel is white (I saw that that sets the background) ... is that messing me up somehow? I am sooo close, but can't quite access the sweet waters.

Most Humbly, Chris

In reply to GD Image Resampling by cdherold

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