I'm working on a project where I need to send images from an ESP32-CAM to Node-Red via MQTT. As the image can be very heavy, I chose to split the string (Base64) into chunks and reassemble it in Node-Red. To reassemble I'm trying to use the Join node, it works, but it adds each chunk as a new line, …

There may be a way with the join node but to get you Moving... If you set the join node to return an array you can use a function node and the array join function... msg.payload = msg.payload.join(""); return msg; [image] [{"id":"e4c8f37e.e68bf","type":"mqtt in","z":"83586cc2.a740b","name":"","…

[image] Steve-Mcl: [{"id":"e4c8f37e.e68bf","type":"mqtt in","z":"83586cc2.a740b","name":"","topic":"PICTURE","qos":"2","datatype":"auto","broker":"d8f5182d.3296f8","x":680,"y":260,"wires":[["8f9355f.de3b6a8","ab2fae17.d62bc"]]},{"id":"8f9355f.de3b6a8","type":"debug","z":"83586cc2.a740b","name":"…

It looks as if the incoming message from MQTT must have a newline on the end. You can't see that in the debug as the string is too long, so feed the MQTT into a function node that extracts the last 10 characters from the string and feed that to a debug to see what is there.

I think the node-red-node-base64 node ignores whitespace so should handle that case just fine and convert it back to a buffer for you.

Hi @dceejay , tanks for your help. Putting base64 node I get this: [image]

/9j/4AAQSkZJRgABAQEAAAAAAAD/2wBDAAoHCAkIBgoJCAkLCwoMDxkQDw4ODx8WFxIZJCAmJiQgIyIoLToxKCs2KyIjMkQzNjs9QEFAJzBHTEY/Szo/QD7/2wBDAQsLCw8NDx0QEB0+KSMpPj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj4+Pj7/xAAfAAABBQEBAQEBAQAAAAAAAAAAAQIDBAUGBwgJCgv/xAC1EAACAQMDAgQDBQUEBAAAAX0BAgMABBEFEiExQQYT…

You need to set it to send to console. Then copy/paste from the console log .

Microsoft Windows [versão 6.1.7601] Copyright (c) 2009 Microsoft Corporation. Todos os direitos reservados. C:\Users\aieser.santos>node-red 18 Sep 11:46:47 - [info] Welcome to Node-RED =================== 18 Sep 11:46:47 - [info] Node-RED version: v1.1.3 18 Sep 11:46:47 - [info] Node.js version:…

Hi thanks for that... for some reason that string has more than one thing in it... The first part goes up to Bpgf/2Q== If I split into 2 then they do both decode ok as [image] so you need to ensure only one arrive at a time

Concatenate Strings from a Payload

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dceejay 15 September 2020 13:25 7

odd - can you share the full output from the debug node just before the base64 node - you may need to set debug to send to console to see the full value and copy/paste it from there.

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Concatenate Strings from a Payload

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