README.md

This repository contains Inatech modifications to raspivid for camera synchronization over network.

Build

On Raspberry Pi:

sudo apt install cmake

git clone https://github.com/inastitch/raspivid-inatech.git

mkdir build && cd build/
cmake ../raspivid-inatech/

# If you type 'make' here, the whole 'userland' code will be compiled
# That's a lot of libraries and binaries.

# Only build 'raspivid' and its dependencies:
make raspivid

# 'raspivid' is found at:
../raspivid-inatech/build/bin/raspivid

# We rename it to avoid confusion with the original binary
sudo mv ../raspivid-inatech/build/bin/raspivid /usr/bin/raspivid-inatech

Run

Notice the new PLL parameters:

-pll, --pll-on	: Enable software PLL
-pllv, --pll-v	: Enable PLL debug output
-plls1, --pll-step1	: PLL framerate correction when drift > 0.1ms
-plls2, --pll-step2	: PLL framerate correction when drift > 1ms

Note: the higher the framerate, the stronger the correction for the software PLL to lock.

Examples

To record H264 at 640x480 @ 30fps, along with timing information (PTS file):

# With RPi camera v2, this will capture on the full sensor.
raspivid-inatech                                 \
    -t 0 -w 640 -h 480 -fps 30 -md 4             \
    --pll-on --pll-step1 150 --pll-step2 300     \
    -cd H264 -o video.h264 -pts video.h264.pts

To record MJPEG at @ 100fps:

# With RPi camera v2, this will capture on a reduced area
# of the full sensor.
raspivid-inatech                                 \
    -t 0 -w 640 -h 480 -fps 100 -md 7            \
    --pll-on --pll-step1 500 --pll-step2 1000    \
    -cd MJPEG -o video.mjpeg -pts video.mjpeg.pts

See RPi camera documentation at:

• https://www.raspberrypi.org/documentation/raspbian/applications/camera.md