Is there a way to read a .pf file also known as picture floatmap file?

Hello, I am new to matlab and I am trying to open and visualize a .pf file as image but I was unable to do so. Is there a way to read .pf file and visualize it as a image.

I link fot the pf file https://drive.google.com/file/d/1BNML47BAD1hHogjxytxaVpOc4LJqvim-/view?usp=sharing. As for the file I cannot see or oopen it.

Any help is appreciated and Thank you so much in advance.

[Cris LaPierre]

Can you tell us more about the file format? How did you create it?

A quick search revealed nothing promising about *.pf files. There was something that sounded similar - a portable floatmap, or *.pfm file.

[Aravind Poolla]

Hi thank you for answering my question.

The file is a measurement file from a software

[Cris LaPierre]

All files are from some software. What software created this file?

[Aravind Poolla]

Hello I dont know from which software the file is from but all I know is it is a measurement file.

Answer 1

[Cris LaPierre]

I found this document, which suggests your file is not a valid pfm file.

Specifically

• The PFM header is 3 consecutive "lines" of ASCII text. Your file has 5 lines
• The identifier line contains the characters "PF" or "Pf". PF means it's a color PFM. Pf means it's a grayscale PFM. You don't appear to have this line.
• The dimensions line contains two positive decimal integers, separated by a blank. The first is the width of the image; the second is the height. Both are in pixels. You file places the values on separate lines.
• The Scale Factor / Endianness line indicates if the numbers are stored in little endian or big endian format. Your file doesn't have this line.

However, with that information, it is possible to turn it into a valid pfm file format and use the function Walter pointed to to load it. BTW, your file uses big endian format. So you just need to replace your header

• Typ=Pic98::TPlane<float>
• Lines=750
• Columns=1125
• FirstLine=0
• FirstColumn=0

With a valid header. I didn't know the scale factor so I used 1.

• Pf
• 1125 750
• s1

Once you've made those changes to your file, you can load and visualize it with the following code. I've attached your file updated to a pfm format. I had to change the extension to txt to be able to attach it here.

img = read_pfm("PF_file.txt", false)
imagesc(img)

[Walter Roberson]

The files appear to be Luminance images from LMK Labsoft; https://www.technoteamvision.com/content/product_overview/photometer_colorimeter/software/lmk_labsoft/index_eng.html

Technical information inside https://www.technoteam.de/apool/tnt/content/e5183/e5432/e5733/e5735/OperationmanualLMKLabSoft_eng.pdf

LMK Labsoft offers export to MATLAB files.

[Aravind Poolla]

Thank you so much for the help.

Answer 2

[Walter Roberson]

https://github.com/banterle/HDR_Toolbox/blob/master/source_code/IO/read_pfm.m

maybe, if you rename to .pfm extension.

[Aravind Poolla]

I have installed and tried the toolbox function with the name changed to .pfm but I got an error unable to resolve the name filename.pfm

[Walter Roberson]

Please show the exact error message, and the line of code you are using to call the function.

[Aravind Poolla]

Here I have added a screenshot

[Walter Roberson]

As suspected, you failed to quote the file name.

img = read_pfm('simulation.pfm', 'bPhotoshopCompatibility')