Automatic looper for video or audio useful for digital posters and audiovisual installations using Raspberry Pi hardware.
- Looks for files stored in a USB device
- Recognized file extensions .mp4, .avi, .mkv, .mp3, .mov, .mpg, .flv, .m4v and .divx
- Audio output is set by default to HDMI but is configurable via config.txt file placed on USB root
- Automatic startup without user intervention when device is powered on
- If more than one file is found will play all in alphabet order and start again
This project is based in only one script that runs on a Raspbian installation. The script will check all files inside the storage device connected to USB port (mounted at /media/usb) and make calls to omxplayer to play each supported file in a endless loop (you can press CTRL-C to cancel).
Code and ideas are taken from other projects listed below at the end of this document.
For the installation you need:
- SD Card 4 Gb or more
- USB storage device like a pendrive or a portable hard disk.
- USB keyboard (only during installation)
- Ethernet cable for internet access using your local network (only during installation)
Download the lastest version of Raspbian and install following the installation instructions to create your SD card with the Raspbian system.
First time you boot the fresh Raspbian installation, the raspi-config menu will appear and you must choose "Expand filesystem" to make usable all the free space in SD card. There are some other options you can change here but are not required for this project.
NOTE: You can always open this utility again by typing sudo raspi-config at command line
Some warnings referring to locale appears when installing some packages. To fix this you have to edit /etc/default/locale file:
sudo nano /etc/default/locale
Put that:
LANG=en_GB.UTF-8
LC_ALL=en_GB.UTF-8
LANGUAGE=en_GB.UTF-8
When is done, press CTRL-O and ENTER to save and CTRL-X to exit.
First at all, you have to update and upgrade packages:
sudo apt-get update
sudo apt-get upgrade
This makes your USB storage easiest to mount at boot and any time you disconnect and connect again.
sudo apt-get install usbmount
Download the script:
cd /home/pi
wget https://raw.githubusercontent.com/kalanda/RPi-MediaLooper/master/videoloop.sh
Add permissions to execute:
chmod +x videoloop.sh
Put a video or audio file in a USB storage device and connect it to Raspberry Pi, then write this at your prompt:
./videoloop.sh
This should play your video in a endless loop. Press CTRL-C anytime to exit.
Our system is not necessary connected to a keyboard to work and has not any sensible data, then autologin is not a problem and makes easy to run our script at startup.
Edit /etc/inittab
sudo nano /etc/inittab
Disable the getty program by adding # to comment this line:
#1:2345:respawn:/sbin/getty 115200 tty1
Add login program to inittab adding the following line just below the commented line
1:2345:respawn:/bin/login -f pi tty1 </dev/tty1 >/dev/tty1 2>&1
This will run the login program with pi user and without any authentication.
When is done, press CTRL-O and ENTER to save and CTRL-X to exit.
To run at startup, edit /etc/profile by typing:
sudo nano /etc/profile
Add /home/pi/videoloop.sh at the end of file
When is done, press CTRL-O and enter to save and CTRL-X to exit.
Now you can reboot your system to test:
sudo reboot
Script will start automatically when systems reboots.
If your system will be placed in a environment where shutdown is done by switching power supply, the SD card can get corrupted easily if shutdown occurs while system is writing data. To prevent this situation is possible to mount all partitions with readonly flag and put logs and pids at RAM memory (erased at shutdown).
Edit /etc/fstab by typing:
sudo nano /etc/fstab
Put ro (readonly) to defaults column of all partitions and add last two lines to mount logs an run in RAM. It should look something like the following.
proc /proc proc defaults 0 0
/dev/mmcblk0p1 /boot vfat ro 0 2
/dev/mmcblk0p2 / ext4 ro 0 1
none /var/run ramfs size=1M 0 0
none /var/log ramfs size=1M 0 0
When is done, press CTRL-O and ENTER to save and CTRL-X to exit. Then run:
sudo partprobe
This alert system to recognize the new partition. Now you can reboot your system to test
sudo reboot
If for some reason you need to make changes to your system, you can remount the read-only partitions with write access:
sudo mount -o remount,rw /dev/mmcblk0p2
Finding a good solution for showing a single video throught projectors in a infinite loop using Raspberry Pi as hardware. I found some interesting projects on Internet but, each one with their pros and cons. I learn a lot testing those but I decided to take the best of all and make my custom project based on my needs.
CuriousTechnologist's solution - link
PROS: Real seamless loop, no blanks or gaps between loops.
CONS: Does not support audio. Is based on a custom binary program coded in C. Requires to prepare videos with a specific feature of h264 codec using AviDemux and naming the file with .h264 extension to work.
StevenHickson's solution - link
PROS: Code is available at GitHub. Is based on omxplayer, which can play almost any video format. Creates a service daemon to autoboot.
CONS: The loop is not seamless, the gap between loops (1 or 2 seconds) depends of the length of video. If you don't use the disk image, the code has some bugs on the installer and the code because uses a standalone version of omxplayer instead the version included by default in Raspbian. When omxplayer plays your videos, uses the -l option for loop, but there are some bugs on this feature. If video has not audio, it hangs on second loop. If video is in a mp4 container, 5 seconds at the end of video will lost in each loop (issue 291).
GeekTips's solution - link
PROS: Just one bash script. Uses the omxplayer that comes with Raspbian that is IMO, the best option to play any video, but instead of -l option for loop (this option has some bugs commented above) the script calls in a infinite while loop to omxplayer for launch the video. Catch for CTRL-C to stop the player.
CONS: Has not online repository for code. Don't provides a autoboot feature.