Here is a Perl script that creates a PDF from list of JPG images. This script uses the PDF::FromImage CPAN module.

#!/usr/bin/env perl
# Perl Script to create a PDF file from a sorted list of JPG images
# This script uses the PDF::FromImage module.
#
# To install PDF::FromImage module on Windows with Strawberry Perl
# execute the following commands in a Command Shell
# The following command assumes Strawberry Perl in PATH
# c:\> perl -MCPAN -e shell
# c:\> install PDF::FromImage;
#
# This script assumes there is a list of 300 JPG images with names 
# in the CURRENT_DIRECTORY in acsending order.
# E.g. fileprefix_1.jpg, fileprefix_2.jpg, fileprefix_3.jpg ...
#
#
# Steps to use the script:
# 1. Save this script as make_pdf.pl in the directory where you have
# the JPG images
# 2. Install the Perl Module
# 3. Edit the script modify as per requirement
# 4. run the script from commandline.
#
use strict;
use PDF::FromImage;
my ($prefix, $pdfname, @files)
# Enter a prefix for your image files
$prefix = 'file_prefix';

# Enter the PDF name without the ".pdf" extension
$pdfname = 'my_pdf_name';

for (my $i=1; $i load_images(@files);
$p->write_file($pdfname . '.pdf');

Perl Script to create a PDF file from a sorted list of JPG images. This script uses the PDF::FromImage module.

To install PDF::FromImage module on Windows with Strawberry Perl
execute the following commands in a Command Shell. The following command assumes Strawberry Perl in PATH

c:\> perl -MCPAN -e shell
c:\> install PDF::FromImage;

This script assumes there is a list of 300 JPG images with names in the CURRENT_DIRECTORY in ascending order.

E.g. fileprefix_1.jpg, fileprefix_2.jpg, fileprefix_3.jpg …

Steps to use the script:

1. Save this script as make_pdf.pl in the directory where you have
   the JPG images.
2. Install the Perl Module.
3. Edit the script modify as per requirement.
4. Run the script from the command line.