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Open Content.php into your wordpress template

Find this code 

<h1 class="entry-title"><?php the_title(); ?></h1> 

Insert The Following Directly After 

<h1 class="entry-title"><?php the_title(); ?></h1> :

this

<?php 
$folder = opendir('/home/black/public_html/_wordpress/wp-content/images');
$i = 0;
while(false !=($file = readdir($folder))){
if($file != "." && $file != ".."){
$images[$i]= $file;
$i++;
}
}
$random_img=rand(0,count($images)-1);	
echo '<img src="/wp-content/images/'.$images[$random_img].'" alt="" />';
?>

Save & close

Create a folder Images in /home/black/public_html/_wordpress/wp-content/images

Upload random images to the folder - (I have 900) Few seconds to scrape them - make them small 20kb to 80kb

create a bash script

nano rename_files.sh

insert the following:

a=1
for i in *.jpg; do
new=$(printf "image_%04d.jpg" "$a") #04 pad to length of 4
mv -- "$i" "$new"
let a=a+1
done

b=1
for i in *.gif; do
new=$(printf "image_%04d.gif" "$b") #04 pad to length of 4
mv -- "$i" "$new"
let b=b+1
done


c=1
for i in *.png; do
new=$(printf "image_%04d.png" "$c") #04 pad to length of 4
mv -- "$i" "$new"
let c=c+1
done

remember to chmod +x
run script with 

./rename_files.sh

Now all your blogs for that template have random images. - Better serp scores