Convert Binary File to ASCI File

Question

Hello, I'm having a little trouble writing a labview program to read a binary file and save it to an ASCI file. The binary file may be large so I've tried to read the file in chunks. I will appreciate any help you could offer. I've attached my .vi below
thanks,
joe
Attachments:
BinToASCI.vi ‏45 KB

Answer 1

I don't really understand what you mean by "the data from the binary file are really huge numbers and don't match what is expected". Are you specifying the correct datatype to the Read function?
As far as your VI is concerned: Your initial statements indicated that you wanted to read this in chunks since you're dealing with very large files. However, while your VI reads in one number at a time, it writes out the whole thing in one big chunk. This is going to be a huge memory draw. You need to write the data to the ASCII file at the same time as when you read it, not after you've read it all. Given this, it makes no sense to only read one number at a time as you're doing. You're going to be performing a disk I/O operation for each number! This is going to take forever, not to mention take a nice bite out of the life expectancy of your hard drive. I don't say this often, but you need to restructure your VI to something like this:
1. Provide dialog to ask for the file to read.
2. Provide dialog to ask for the file to write to.
3. Write out your header to the output file.
4. Start a loop where the number of iterations is based on the number of times you have to read the file using a max chunk size. This is based on the file size and the size of the chunk that you're comfortable in reading. The chunk size is dependent on your machine - i.e., speed and amount of RAM.
5. Read that many numbers and write out the converted numbers.
6. Repeat until done.
7. Close both files.
See attached file as a starting point. The error handling is not that great, so keep that in mind.
Message Edited by smercurio_fc on 03-17-2006 05:20 PM
Attachments:
Read Chunks.vi ‏68 KB