OCR document processing from LINE/Gmail using GPT-4o to Google Workspace

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Important notice

This workflow is provided as-is. Please review and test before using in production.

1. Workflow Overview

Who this is for Users who frequently receive images or documents via LINE or email Teams needing automatic OCR + AI summarization Anyone who wants hands free document processing and structured stor...

Best for

Document Extraction automation workflows
AI Summarization automation workflows
advanced n8n builders looking for reusable templates

Tools used

n8n-nodes-base.webhook, n8n-nodes-base.gmailtrigger, n8n-nodes-base.set, n8n-nodes-base.merge, n8n-nodes-base.googledrive, n8n-nodes-base.code, n8n-nodes-base.gmail, n8n-nodes-base.if

Source and attribution

This workflow is cataloged by N8N Workflows and links back to its original n8n.io source page by SOLOVIEVA ANNA.

Original n8n.io source

1.1 Workflow description

Title: OCR document processing from LINE/Gmail using GPT-4o to Google Workspace
Workflow name: OCR document processing from LINE/Gmail using GPT-4o to Google Workspace

Who this is for

Users who frequently receive images or documents via LINE or email

Teams needing automatic OCR + AI summarization

Anyone who wants hands-free document processing and structured storage

How it works

Triggers: LINE Webhook and Gmail IMAP Trigger capture incoming messages or emails.

Source Tagging: Inputs are tagged as LINE or EMAIL for later branching.

File Handling: Files are uploaded to Google Drive and converted for analysis.

OCR: An AI vision model extracts all readable text from the document image.

AI Summarization: A text model produces a concise summary.

Logging: The summary is appended to Google Sheets for record-keeping.

Email Drafting: A Gmail Draft is generated containing the OCR text and summary.

How to set up

Connect your LINE, Gmail, OpenAI, and Google Drive/Sheets credentials.

Update folder IDs, sheet names, and authentication fields as needed.

Optional: customize summarization instructions.

Customization ideas

Add translation or classification steps

Modify output format for Slack/Notion

Store files in date-based Drive folders

1.2 Logical Blocks

This catalog entry is organized from the workflow JSON. The node-level section below shows the executable blocks available for review before importing the template.

2. Block-by-Block Analysis

Block 1 - LINE Webhook

Type / Role: n8n-nodes-base.webhook - webhook
Config choices: Version 2.1

Block 2 - Gmail IMAP Trigger

Type / Role: n8n-nodes-base.gmailTrigger - gmailTrigger
Config choices: Version 1.3

Block 3 - Workflow Configuration

Type / Role: n8n-nodes-base.set - set
Config choices: Version 3.4

Block 4 - Tag Source - LINE

Type / Role: n8n-nodes-base.set - set
Config choices: Version 3.4

Block 5 - Tag Source - EMAIL

Type / Role: n8n-nodes-base.set - set
Config choices: Version 3.4

Block 6 - Merge Triggers

Type / Role: n8n-nodes-base.merge - merge
Config choices: Version 3.2

Block 7 - Upload to Google Drive

Type / Role: n8n-nodes-base.googleDrive - googleDrive
Config choices: Version 3

Block 8 - Convert to Base64

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 9 - Create Gmail Draft

Type / Role: n8n-nodes-base.gmail - gmail
Config choices: Version 2.1

Block 10 - If

Type / Role: n8n-nodes-base.if - if
Config choices: Version 2.2

Block 11 - Append row in sheet

Type / Role: n8n-nodes-base.googleSheets - googleSheets
Config choices: Version 4.7

Block 12 - Code in JavaScript

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 13 - HTTP Request2

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.2

Block 14 - Analyze image

Type / Role: @n8n/n8n-nodes-langchain.openAi - openAi
Config choices: Version 1.8

Block 15 - Message a model

Type / Role: @n8n/n8n-nodes-langchain.openAi - openAi
Config choices: Version 1.8

Block 16 - HTTP Request

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.2

Block 17 - Wait

Type / Role: n8n-nodes-base.wait - wait
Config choices: Version 1.1

Block 18 - Sticky Note - Overview

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 19 - Sticky Note - Triggers & Configuration

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 20 - Sticky Note - Source tagging & merge

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 21 - Sticky Note - File upload & OCR

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 22 - Sticky Note - Summaries & outputs

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

3. Summary Table

Workflow	OCR document processing from LINE/Gmail using GPT-4o to Google Workspace
Complexity	advanced
Nodes	22
Categories	Document Extraction, AI Summarization
Author	SOLOVIEVA ANNA
Published	02 Dec 2025

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

Use the JSON export at /data/workflows/11413/11413.json as the source template for this automation.
2. Import the template into n8n

Open n8n, import the downloaded JSON, and review each node before activating the workflow.
3. Configure credentials and variables

Replace placeholder credentials, API keys, webhook URLs, account IDs, and environment-specific values with your own settings.
4. Test with sample data

Run the workflow manually or in a staging workspace, inspect node output, and confirm downstream systems receive the expected data.
5. Activate and monitor

Enable the workflow only after testing, then monitor executions, errors, and rate limits during the first production runs.

5. General Notes & Resources

Review imported nodes carefully before activation. This catalog entry is intended to help you inspect the workflow structure, understand required services, and find related templates faster.

Node names, credentials, schedules, webhook paths, and external service limits may need adjustment for your workspace.

Download workflow JSON Original n8n.io source Document Extraction workflows AI Summarization workflows

Frequently asked questions

What does OCR document processing from LINE/Gmail using GPT-4o to Google Workspace do?

What do I need before importing this workflow?

Review the workflow JSON, configure any required credentials in n8n, and test the automation in a safe workspace before using it in production.

Can I customize this workflow?

Yes. Use the block-by-block analysis and the downloadable JSON to inspect each node, then adjust credentials, prompts, schedules, filters, or destinations for your Document Extraction, AI Summarization use case.

SOLOVIEVA ANNA

5 workflows

Nodes

n8n-nodes-base.webhook n8n-nodes-base.gmailtrigger n8n-nodes-base.set n8n-nodes-base.merge n8n-nodes-base.googledrive n8n-nodes-base.code n8n-nodes-base.gmail n8n-nodes-base.if

Complexity

advanced

Published 02 Dec 2025

Likes 0

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Install path: /data/workflows/11413/11413.json

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OCR document processing from LINE/Gmail using GPT-4o to Google Workspace

Workflow preview

Important notice

1. Workflow Overview

Best for

Tools used

Source and attribution

1.1 Workflow description

1.2 Logical Blocks

2. Block-by-Block Analysis

Block 1 - LINE Webhook

Block 2 - Gmail IMAP Trigger

Block 3 - Workflow Configuration

Block 4 - Tag Source - LINE

Block 5 - Tag Source - EMAIL

Block 6 - Merge Triggers

Block 7 - Upload to Google Drive

Block 8 - Convert to Base64

Block 9 - Create Gmail Draft

Block 10 - If

Block 11 - Append row in sheet

Block 12 - Code in JavaScript

Block 13 - HTTP Request2

Block 14 - Analyze image

Block 15 - Message a model

Block 16 - HTTP Request

Block 17 - Wait

Block 18 - Sticky Note - Overview

Block 19 - Sticky Note - Triggers & Configuration

Block 20 - Sticky Note - Source tagging & merge

Block 21 - Sticky Note - File upload & OCR

Block 22 - Sticky Note - Summaries & outputs

3. Summary Table

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

2. Import the template into n8n

3. Configure credentials and variables

4. Test with sample data

5. Activate and monitor

5. General Notes & Resources

Frequently asked questions