Example of streaming images over Internet. Single image, java script auto refresh and Motion JPEG.

[telles_s]

This example project uses LabVIEW Web Services to publish and stream images over internet.

Project content

• startup.vi responsible to initialize resources, monitor the Web Service status and close resources if the Web Service be stopped or Stop button pressed.
  

• Single_Image.vi is a GET HTTP Method configured as Stream Output Type. It uses the native image/jped HTTP Response MIME Type from LabVIEW Web Services library to publish a single IMAQdx image, previously acquired in Grab mode and flattened as JPEG/Image binary stream. The image can also be resampled.

• JS_Auto_Refresh.vi is a GET HTTP Method configured as Stream Output Type. It uses the native text/html HTTP Response MIME Type from LabVIEW Web Services library to publish a JavaScript and a html image frame, the image source is the Single_Image method and the JavaScript will refresh the image according to the time gap specified.

Thanks: https://stackoverflow.com/questions/20877813/auto-refresh-images-in-html

• MJPEG.vi is a GET HTTP Method configured as Stream Output Type and deselected the “Use Headers” to LabVIEW Web Services not include the HTTP Headers, because it uses a non native HTTP MIME Type for stream MJPEG images over HTTP.

Ref1: https://en.wikipedia.org/wiki/Motion_JPEG#M-JPEG_over_HTTP

Ref2: http://www.ietf.org/rfc/rfc2616.txt

OBS: MJPEG over HTTP is not supported by Internet Explorer natively, it is required to install an add-on, at least when I tested it. I didn’t investigate much though.

How to run

1.          Open the project

2.          Right-click on “myWebService” and select “Start”

3.          Right-click in on of methods, e.g. MJPEG.vi and select “Show URL Method…”

4.          Copy this URL in an Internet Browser

Final considerations

Dependencies: NI Vision Acquisition Software

Hardware tested: Laptop with Webcam, cRIO-9068 with Basler USB3.0 camera and sbRIO-9651 + Dev Kit with Basler USB3.0 camera

[Ravenink]

Hi.

Thank you so much for sharing this. It has been extremelly useful for me, and also really easy to use. It works like a charm.

How difficult would it be to deploy this as a source distribution instead of using it as a LabView project? For my needs, I would need to be able to use the startup.vi outside the project. 

[telles_s]

Motion JPEG over HTTP - Multiple Access

[Noriker]

Hi, tried to run the example, but web service refused to start, giving error code 67003. Disabling SSE2 did not solve the problem. Please advice. Thanks.

[Ravenink]

Same thing happens to me, Noriker. I can run it in debug mode (port 8001), but not in production (port 8080).