Transmit a ppm image or an image taken with a raspberry Pi Camera with two LoRa modem. With this communication protocol, you can use a reliable mode. It means that the receiver communicate the missing packets to send again while all the packets are not received If some packets can't be send received, you can build the image whatever and the missing pixels will be fills with black color.
First you need to update & upgrade your Raspberry Pi
sudo apt-get update
sudo apt-get upgrade
Then we need to install imagemagick to convert jpg and ppm image
sudo apt install imagemagick
sudo apt-get install git
git clone https://github.com/MorgesHAB/LoRaImageTransmission
Then if your modem is the transmitter, type
make Transmitter
Or if it is the receiver modem, type
make Receiver
For the transmitter software
./Transmitter image.ppm
./Transmitter livePicture
./Transmitter image.ppm [packet number]
for the receiver software
./Receiver
sudo apt install apache2
Change the right of this directory
sudo chown -R pi:www-data /var/www/html/
sudo chmod -R 770 /var/www/html/
Then install php
sudo apt-get intsall php5 libapache2-mod-php5
Now we will program in php so delete the html file and create a php one
sudo rm /var/www/html/index.html
echo "<?php phpinfo(); ?>" > /var/www/html/index.php
Now you can check that the server is working by typing the IP address of the Pi on a web browser.
for example : 192.32.12.45
Illustration of the two LoRa modem, one on a Raspberry Pi zero and one on a RPi 3B