From hex to jpeg.

[ASibbern]

Hello.

I'm trying to generate a JPEG picture from a hexadecimal textfile ultimatly directly from a serial port, and I'm alittle stuck on the execution.
After some googeling I think I've understood that you need to arrange the hexadecimals in an array and then generate the picture.

But doing so only generates a almost black picture with som white dots, so something is very wrong.
Could anyone give alittle heads up to what I may be doing wrong?

I've attached the file with the picture in hex.

Thanks in advance,

ASibbern

[PaulieQ]

Hi,

I had the same problem once.

I made a VI that captured a waveform from an oscilloscope. The problem was that during the transmission some extra bits, at the beginning were added.

I did the following:

- changed the capture format to a format that can be easily interpreted (bmp or tiff)

- capture the waveform and compare it to the standard file (from your PC)

- remove extra characters and try it again with jpeg

Personally, I prefer TIFF - because it's easy and fast to read the tags. Capture as tiff and compare what you get with a tiff from your PC. I think that the first information from a tiff is little endian or big endian (search on google how exactly starts tiff or bmp files).

Paul

[PaulieQ]

on more thing: write it in binary form not as text.

[MikeS81]

Hi ASibbern,

the attached example shows how it could work. It shows how you can create your image from the txt file. If you show us your code, maybe we will find a simpler solution to write the image directly.

Mike

[ASibbern]

Thank you

I am connected to a JPEG color cam with a serial port,

so the first part is just taking picture.

i wish to stream it like a video