JPEG decode: how to use it?

[Philippe Bruyant]

Hello experts,
I am using Labview 7 Express and Windows XP.
I am downloading continuous datastreams of JPEG images from network cameras (Motion-JPEG streams, not MPEG).
I use the TCP Read VI to get the streams, and I save them to disk on the fly. It works really great. I can also extract the JPEG files from the M-JPEG files on the fly, which works fine too. Now, I would like to display the JPEG images, using the JPEG Decode VI, but I am puzzled about how to do that: the output of the VI is a cluster of a string and a U32 number. What am I supposed to do with this number ? Is it a pointer?
Thanks!
Philippe

[Philippe Bruyant]

OK, I have the answer to my own question: the output of JPEG Decode is to be used as an input to IMAQ Wind Draw VI.
What can I do if I don't have the IMAQ Vision package?
Phil

[Wiebe@CARYA]

Hi,

Use the vis under Graphic & Sound > Picture Formats.

Regards,

Wiebe.

"Philippe Bruyant" wrote in message
news:5065000000050000005AA20100-1079395200000@exchange.ni.com...
> OK, I have the answer to my own question: the output of JPEG Decode is
> to be used as an input to IMAQ Wind Draw VI.
> What can I do if I don't have the IMAQ Vision package?
> Phil

[Philippe Bruyant]

I have connected the output of the JPEG Decode VI to an IMAQ ImageToArray VI, and this latter to Draw Unflattened Pixmap VI. It seems to work, although I have trouble with the colormap (the image looks like garbage).
Thanks
Philippe

[Torfins]

Philippe,
I am trying to do the exact same thing as you here: I have a network camera (Axis 206), and I am currently using 'URL Get HTTP Document.vi' to receive the stream og MJPG (multipart JPEG's). This works fine, but I have som problems displaying and compressing the images. At the end, logging data from a DAQ-card is supposed to be combined with the image stream into a single file.

The 'IMAQ JPEG Decode.vi' is supposed to compress the images into a binary format. I have tried the setup you proposed, but any way I implement this vi the vi executes for less than a second and Labview shuts down.

Any ideas what may be wrong? Displaying live JPEG's (not from a file) is obviously not something NI gave much thought.