What is the input "key" in the IMAQ Write Custom Data palette?

[fbcaval]

Hello!

I am not able to use correctly the IMAQ Write Custom Data palette because I do not know what is the input "key".

Does anyone know its meaning?

Sincerely,

Fábio Machado Cavalcanti

Canada-Brazil Science Without Borders Student

Lakehead University, Thunder Bay, Ontario, Canada

Federal University of Pernambuco (UFPE), Recife, PE, Brazil

Undergraduate Student in Chemical Engineering

[ninadregundwar]

Hi

there a key associated with each and every image. If the key is not present then this function assigns the key that you have specified to that image and if the key is already present the the function overwrites the key with the new key thet you have specified.

[fbcaval]

Thank you for replying Ninad Regundwar!

I agree with this. I have already read this information in the LabView Help.

However, I would like to know what is the "key" specifically. I know that it is a string.

I have written a code to add some acquisition features in a PNG Image File. For this, I have used the following palettes: IMAQ Write File 2 - PNG with Vision Info and IMAQ Write Custom Data.

Afterwards, I have written another code to read the acquisition features from this PNG Image File. For this one, I have used the following palettes: IMAQ Read Image and Vision Information and IMAQ Read Custom Data.

But, when I am reading the acquisition features, an error message appears: "ERROR -1074395723 occurred at IMAQ Read Custom Data - IMAQ Vision: The key you specified cannot be found in the image"

I do not know what I have to put in the input "key". So, I have been trying different values for it: "data", "hello", "13", "56", etc. But, none of these has worked and the same message has appeared.

Does someone know what I have to put in the input "key"? Does someone have an example that shows how to use the palettes: "IMAQ Write Custom Data" and "IMAQ Read Custom Data" correctly?

Sincerely,

Fábio Machado Cavalcanti

Canada-Brazil Science Without Borders Student

Lakehead University, Thunder Bay, Ontario, Canada

Federal University of Pernambuco (UFPE), Recife, PE, Brazil

Undergraduate Student in Chemical Engineering

[MoviJOHN]

The work "Key" here is being used in the context of Key/Value pair.  Think of KEY as being VARIABLE_NAME and CUSTOM_DATA_IN as VARIABLE_VALUE.

The KEY is how you retrieve the value later using a read command.  If you need to save the image to file, and you need to store custom data, you also need to use PNG with Image data as your WriteImage instance.