Hey All! I am been really struggling on this problem and thought it was time to reach out. I need to convert a KNIME Binary Object (an image binary return from an API) to a Base64 string so I can use it in PowerBI to display an image in a dashboard. I have tried everything I can think of to get the Binary to Base 64 and I have been unsuccessful. I need to end up with a string output something like this: /9j/4AAQSkZJRgABAQEAYABgAAD/2wBDAAEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQH/2wBDAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQH/wAARCAFoAWgDASIAAhEBAxEB/8QAHwAAAQUBAQEBAQEAAAAAAAAAAAECAwQFBgcICQoL/8QAtRAAAgEDAwIEAwUFBAQAAAF9AQIDAAQRBRIhMUE My data from the GET: [image] My data after Binary To String with ASCII set as the Decode: [image] I am not very proficient in JAVA and wrote this to try to convert the Binary to a Base64 string: [image] The JAVA Snippet outputs this: [image] I tried in Python as well and ended up with a similar result: import base64 import pandas as pd input_table_1['body_encoded'] = [base64.b64encode(x.encode('ASCII', 'strict')) for x in input_table_1.body] print(input_table_1['body_encoded']) output_table_1 = input_table_1 The output from my Python Script [image] It just doesn’t look like the Base64 I’m getting from the online conversion tools. I am open to a JAVA, R or Python solution to this if anyone has any ideas/suggestions. I really appreciate it!

Hi @TardisPilot , I got it to work! As I suspected, the code that I gave you was to convert a string to Base64, while you want to convert a binary object to Base64, so it needed some modification. Taking a step back, the Base64.encodeBase64String() function takes a Byte array (byte[]), and in case of a string, we simply used the .getBytes() method like this stringVariable.getBytes(). However, with the binary object, or more precisely an InputStream, you can’t use this method, but we still need to convert to a Byte array (most of the Base64 methods take a Byte array as argument). I used the toByteArray() method from the IOUtils libraries (org.apache.commons.io.IOUtils), so you will need to have the “apache commons io” jar files to use it: https://commons.apache.org/proper/commons-io/download_io.cgi This is what the Java Snippet looks like in the end: [image] And you point to the jar file like this: [image] And here is the result of the Base64 encoded (top part from the Base64 Encoder node, bottom part from Java Snippet): [image] And here’s the workflow: Image_Base64_Test.knwf (760.9 KB) I added it as a new node: [image]

Convert Binary To Base64

KNIME Analytics Platform

ipazin June 9, 2021, 1:39pm 2

Hello @TardisPilot,

maybe this topic helps:

Br,
Ivan

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