⚠️ Project Deprecated — DispmanX API No Longer Supported

This project is no longer functional on current Raspberry Pi OS releases. The underlying DispmanX API, which this code depends on, has been removed and is no longer supported in modern Raspberry Pi graphics stacks (Wayland, KMS, DRM).

raspi2png

Utility to take a snapshot of the raspberry pi screen and save it as a PNG file. Works with all Raspberry Pi boards.

Usage: raspi2png [--pngname name] [--width <width>] [--height <height>] [--compression <level>] [--delay <delay>] [--display <number>] [--stdout] [--version] [--help]

--pngname,-p - name of png file to create (default is snapshot.png)
--height,-h - image height (default is screen height)
--width,-w - image width (default is screen width)
--compression,-c - PNG compression level (0 - 9)
--delay,-d - delay in seconds (default 0)
--display,-D - Raspberry Pi display number (default 0)
--stdout,-s - write file to stdout
--savepath,-a - save path
--version,-v - print version number
--help,-H - print this usage information

Simple Install

Run this command through terminal or CLI screen.

curl -sL https://raw.githubusercontent.com/GrazerComputerClub/raspi2png/master/installer.sh | bash -

Manual Building

You will need to install libpng before you build the program. On Raspbian / Raspberry Pi OS execute
sudo apt-get install libpng-dev
Then just type 'make' and 'make install' in the raspi2png directory you cloned from github.

Execute with print key (triggerhappy)

create configuration file '/etc/triggerhappy/triggers.d/printscr.conf':

KEY_SYSRQ	1	/usr/bin/raspi2png -a /home/pi/snapshot

execute following commands:

mkdir /home/pi/snapshot
chmod g+w /home/pi/snapshot 
sudo chown nobody /home/pi/snapshot
sudo adduser nobody video
sudo service triggerhappy restart

Hardware GPIO input for print key (BCM26 active low)

Command-line:

sudo dtoverlay gpio-key gpio=26 keycode=99 label="KEY_SYSRQ" gpio_pull=2

config.txt:

dtoverlay=gpio-key,gpio=26,keycode=99,label="KEY_SYSRQ",gpio_pull=2

Benchmark

raspi2png 1.1, 720p screen, Raspberry Pi 3 B, RAM-disk

compression	seconds	size (KiB)
0	0,23	2705
1	0,42	676
2	0,42	654
3	0,53	624
4	0,57	606
5	0,71	593
6	1,10	575
7	1,46	569
8	3,04	564
9	5,30	560

optipng size: ~553 KiB