In n8n, binary data is already base64 encoded internally, so you don't need to re-encode it. Your approach of accessing the binary property from the previous node and directly using it as base64 is correct. One thing to double-check is that you access the base64 string via binaryData.data (not just binaryData) since binaryData is an object containing data and metadata. Also, ensure your next node or HTTP request to Odoo sends the base64 string properly in the JSON payload without additional encoding.