How to I get variables from location in nginx?

The location from nginx conf:

location ~/photos/resize/(\d+)/(\d+) {
    # Here var1=(\d+), var2=(\d+)
}

How to I get variables from location in nginx?

The regex works pretty much like in every other place that has it.

location ~/photos/resize/(\d+)/(\d+) {
  # use $1 for the first \d+ and $2 for the second, and so on.
}

Looking at examples on the nginx wiki may also help, http://wiki.nginx.org/Configuration

In addition to the previous answers, you can also set the names of the regex captured groups so they would easier to be referred later;

location ~/photos/resize/(?<width>(\d+))/(?<height>(\d+)) {
  # so here you can use the $width and the $height variables
}

see NGINX: check whether $remote_user equals to the first part of the location for an example of usage.

You may try this:

location ~ ^/photos/resize/.+ {
    rewrite ^/photos/resize/(\d+)/(\d+) /my_resize_script.php?w=$1&h=$2 last;
}