How do I create movie clips (AVI, MPEG, or other) with LV 7.0 without IMAQ Vision?

[Bruce_Mac_Donald]

I have an LV 7.0 program that scans a large array and displays data in an intensity plot, as well as a BMP image. I would like to create an AVI, MPEG, or other movie clip file with this data, without using IMAQ Vision. Can this be done? If I have to create a clip of the whole screen that is fine too.

[Sheldon_Stokes]

when making a movie of the screen, I've used a program called snag-it.

I've also made pseudo movies of a contour plot by outputting PNG's of each frame and then assembling them into an animated GIF.



Sheldon

[Scott_R]

Hello Bruce,

If you have the NI-IMAQ drivers installed, there are several VIs for the creation of AVIs. These VIs (IMAQ AVI Create, IMAQ AVI Write Frame, and IMAQ AVI Close) will be located in the Function Palette under "All Functions >> NI Measurements >> Vision >> Vision Utilities >> Files." These VIs will allow you to build uncompressed AVI files. If you want to perform any kind of compression on these AVIs, then you will either need Vision or some other third-party software.

If you have not installed the NI-IMAQ drivers, you can find them at:

NI-IMAQ Version 3.1 for Windows 2000/NT/XP
http://digital.ni.com/softlib.nsf/websearch/46C9287B4FC57C1686256FA10081E38E?opendocument&node=132060_US

Try that and let me know if you have any additional questions.

Regards,
Scott R.
Applications Engineer
National Instruments

[Bruce_Mac_Donald]

Thanks for your help. Snag It seems to work, although I would rather have a way for LabVIEW to do it directly. The IMAQ routines, as suggested, seem the better route. I haven't tried it yet though.

Thanks again.

[Bruce_Mac_Donald]

Scott, I found the three VI's you mentioned. I can figure out how to open, write, and close AVI files with them. However, I have one more question that may seem simple to you - how do I convert an intensity graph (or other graph or chart) to an image that can then be written to a file? Is there an example showing how to do this?

Thanks.

[Scott_R]

Bruce,

This functionality would require the use of the Vision Development Module. This software includes VIs called IMAQ ArrayToImage and IMAQ ArrayToColorImage. These functions convert array data into the image format. The IMAQ functions are designed for the acquisition of images for display and saving to disk. The Vision functions are designed for the processing of existing images that were either acquired from a camera or exist on the hard disk.

If you have the LabVIEW Full or Professional Development System, then you have the Graphics and Sound palette. Using the VIs in this palette, you may be able to make use of the Write JPEG/BMP/PNG File and Read JPEG/BMP/PNG File VIs. With the Write VIs, you could pass in your array of data, generate an image, then load the image and display it into a Picture Control on your front panel. You won't be able to do any manipulation of the image, but you would at least be able to display.

Regards,
Scott R.
Applications Engineer
National Instruments

[Bruce_Mac_Donald]

Scott, thanks again. I will talk to my client but I believe the IMAQ Vision application is the only solution for them because they wish to use the movies in other applications.

[ColinAE]

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@Bruce Mac Donald wrote:
Scott, I found the three VI's you mentioned. I can figure out how to open, write, and close AVI files with them. However, I have one more question that may seem simple to you - how do I convert an intensity graph (or other graph or chart) to an image that can then be written to a file? Is there an example showing how to do this?

Thanks.

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Hello.

You can use a method like the VI (LV7.1) that I have attached here. There is a method associated with each control called Get Image. This method outputs an image data cluster that can be used with the native LabVIEW image I/O VIs.

This should get you going.