Timestamp of image

[Francois Aujard]

Hello,

I have a GiGe camera Basler. I have created a ring acquisition like the exemple IMAQdx with circular buffer. I load an image every 15ms and I add it in a Vi type FGV (cf. Stock Images.png). In the FGV vi,  I create 2 tables. One is for the timestamps and the seconds is for the images. I use the timestamp table juste for keep the last 15s. If my test crash I save the images table. 

If I use the Vi to look at the timestamp of my image table, it is not the same timestamp as when I added the image in the table (cf. Save Images.png). Why? The propreties IMAQdxReceiveTimestampHigh and IMAQdxReceiveTimestampLow are not attached to the images? 

I hope you understand my English 🙂 (thank you deepl)

 

François A.

[Francois Aujard]

In fact with IMAQdx, I want to create a 15s frame buffer, at a rate of about 60fps. A priori the image data I'm trying to store must be a reference. So it can't work. If I convert the reference to a Variant I have the same problem. And if I flatten it into a string, my execution time becomes too long...

Does anyone have an idea or an advice?

 

[Rolf Kalbermatter]

On 9/21/2022 at 3:59 PM, Francois Aujard said:

In fact with IMAQdx, I want to create a 15s frame buffer, at a rate of about 60fps. A priori the image data I'm trying to store must be a reference. So it can't work. If I convert the reference to a Variant I have the same problem. And if I flatten it into a string, my execution time becomes too long...

Does anyone have an idea or an advice?

IMAQ Vision images are by reference, not by value as other LabVIEW data types. And their identifying attribute is the name used when creating that IMAQ Vision image. Making a variant of the image doesn't change anything about the fact that this image is still a reference to to same memory area that the IMAQ refnum refers to.

So if you want to create a buffer of 15s at 60 mages per second you would have to create 900 buffers. That's a lot of memory if you don't use old low resolution cameras.

Edited November 11, 2022 by Rolf Kalbermatter

[Francois Aujard]

After several attempts I finally figured this out and switched to the 64 bit version of labview... Because in the 32 bits version I was getting a memory error when I had a big buffer of images...

Thank for your message @Rolf Kalbermatter