schneider-engineering / openpnp-capture

A cross platform video capture library with a focus on machine vision.

openpnp-capture

OpenPnP Capture is a cross platform video capture library with a focus on machine vision. It's goals are:

• Native camera access on Windows, Linux and Mac. Implemented with DirectShow, V4L2 and AVFoundation respectively.
• Named device enumeration.
• Strong, repeatable unique IDs.
• Format control with support for at least YUV and MJPEG. MJPEG will allow the use of multiple USB cameras on a single hub.
• Auto and manual exposure control.
• Auto and manual focus control.
• Simple, common C wrapper for the listed APIs.

Status

Windows

Feature	Implemented
Device Enumeration	Yes
Capturing	Yes
MJPEG formats	Yes
YUV formats	Yes
Exposure control	Yes
Focus control	Yes / Untested
Zoom control	Yes
Gain control	Yes
White balance control	Yes
Framerate control	No

Linux

Feature	Implemented
Device Enumeration	Yes
Capturing	Yes
MJPEG formats	Yes
YUV formats	Yes, YUYV/YUV2
Exposure control	Yes
Focus control	Yes / Untested
Zoom control	Yes
Gain control	Yes / Untested
White balance control	Yes
Framerate control	No

OSX

Feature	Implemented
Device Enumeration	Yes
Capturing	Yes
MJPEG formats	Yes (dmb1)
YUV formats	Yes
Exposure control	Yes / Experimental
Focus control	Yes / Experimental
Zoom control	Yes / Experimental
Gain control	Yes / Experimental
White balance control	Yes / Experimental
Framerate control	No

TODO

• support for re-enumeration.

Building OpenPnP Capture

Dependencies

• CMAKE 3.1 or better
• MAKE (osx, linux)
• Visual Studio 2013 + NMake or Ninja Build (windows)
• NASM for building libjpeg-turbo (linux)

Build instructions (Windows)

Run the batch file 'bootstrap.bat' and choose the desired build system (VisualStudio/nmake or Ninja). Make sure the compiler (Visual Studio) is in the search path.

Go to the build directory and run nmake or ninja to build the library and the test application.

Build instructions (OSX)

Run 'bootstrap_osx.sh'. Run make.

Build instructions (Linux)

Run 'bootstrap_linux.sh'. Run make.

Supporting other platforms

• Implement all PlatformXXX classes, like in the win or linux directories.
• PlatformContext handles device and internal frame buffer format enumeration.
• PlatformStream is responsible for capturing and decoding the camera stream to a 8-bit per channel RGB frame buffer.
• Statically link external dependencies.

Downloading Binaries

openpnp-capture is still under development, but you can download releases that are built automatically from https://github.com/openpnp/openpnp-capture/releases/latest.