@seanmor5
I want to invert the cat image. Therefore I downloaded the file in the same folder as the livemd file for chapter 03 I created.
I use the code:
"Cat.jpg"
|> StbImage.read_file!()
|> StbImage.resize(256, 256)
|> Nx.dot(invert_color_channels)
|> Nx.as_type({:u, 8})
|> Kino.Image.new()
returns:
** (ArgumentError) could not open file
(stb_image 0.6.2) lib/stb_image.ex:247: StbImage.read_file!/2
/path_to_folder/ch03_harness_the_power_of_math.livemd#cell:4r2dpa25qaotbzseednwllnwqlrrvd6l:8: (file)
Hope you can help me out here.
Hey @sehHeiden,
That’s because StbImage.read_file!() expects an absolute path to the image file.
# Expects
StbImage.read_file!("/path/to/Cat.jpg")
Assuming it’s in the same folder as your Livebook .livemd, we’ll need to figure out the current directory relative to your .livemd & image are in.
We do that via the following:
__DIR__: Returns the absolute path of the directory of the current file as a binary.Path.join: Joins two paths.
Putting it together
__DIR__
|> Path.join("Cat.jpg")
|> StbImage.read_file!()
|> StbImage.resize(256, 256)
|> StbImage.to_nx()
|> Nx.dot(invert_color_channels)
|> Nx.as_type({:u, 8})
|> Kino.Image.new()
That should locate the file correctly & invert the image:
Hope it helps!
I assume my problem was, that I thought my local folder is where the livemd file is in, but It seems, its the folder from which the shell starts the livebook programme.
