Clipboard image to data-uri

[gingerbeardman]

I often have to generate data-uri for some bitmap data.

 

Previously I had to save the data to a file and process it that way.

I needed to support

- data currently in clipboard

 

I can get old data from clipboard history and make it current clipboard

 

My workaround is using `pngpaste` terminal command and a workflow that does:

#!/usr/bin/env bash
echo "data:image/png;base64,$(pngpaste -b)" | pbcopy

 

https://www.gingerbeardman.com/alfred/image to data-uri.alfredworkflow

 

That works well.

 

I'm wondering if there is a more efficient way to do this in Alfred that relies only in built-in tools?

 

matt

[vitor]

Here’s how you can save image data from the clipboard via AppleScript, with quite a bit of error handling. This particular code saves it to the Desktop, named as a screenshot. WebScreenshot can do it too.

 

try
  set imageData to the clipboard as {«class PNGf»}
on error
  tell me to error "Clipboard data does not seem to be an image"
end try

set filePath to (POSIX path of (path to desktop folder)) & (do shell script "date +'Screenshot %Y-%m-%d at %H.%M.%S.png'")

tell application "System Events" to if filePath exists then tell me to error "Path exists: " & filePath

set imageFile to open for access filePath with write permission
write imageData to imageFile
close access imageFile

 

Alternatively, look inside ~/Library/Application Support/Alfred/Databases/clipboard.alfdb.data which has the images stored as tiffs. You can convert them to PNG with the Convert Image Format Automation Task.

[gingerbeardman]

Thanks, not quite what I was looking for.

 

I need the data-uri (base64) of the image, and the process needs to be transient - I don't want files to be created on disk.

 

This is what my workflow does (produces base64 of the current clipboard image) but it relies on the third party tool pngpaste 

[vitor]

Right. I may still be able to help but to give the best answer I need to understand what’s the scope of the request. You want to get the base64 of the image without any dependencies on software which does not ship by default with macOS, correct? That is simpler if you create a temporary image then run the base64 command on it.

I’ll simplify the code above and show what I mean. Note how it creates the image in the tmp directory.

 

set imageData to the clipboard as {«class PNGf»}

set filePath to (POSIX file "/tmp/base64image.png")

 

set imageFile to open for access filePath with write permission

write imageData to imageFile

close access imageFile

 

Then you connect that to a Zsh Run Script:

echo "data:image/png;base64,$(base64 --input=/tmp/base64image.png)" | pbcopy
rm '/tmp/base64image.png'

You don’t even need to rm the image if you don’t want, as /tmp is cleaned up on reboots and the AppleScript overwrites the path.

[gingerbeardman]

Thanks! That seems to be it, I will give it a try.

 

I like to keep my brew/dependencies to a minimum, as that thing takes so long to do updates if left unchecked.

[vitor]

Note that since February Homebrew gets the list of formulae and casks from a JSON, it no longer git pulls the whole repo. Updates are much faster. But yes, I also prefer to do things with as few dependencies as possible.

 

Edited April 26, 2023 by vitor

[gingerbeardman]

That's good news!