Translating

Doco Translate provides a comprehensive translation workflow for PDF documents. This page covers everything you need to know about configuring and running translations.

Opening a PDF

Doco Translate supports two methods for importing PDF files:

Local Files

• Drag and drop a PDF file into the Doco Translate home screen.
• Click Open File and select a PDF from the file picker.
• Doco Translate copies the file into its own storage so the original remains untouched.

Online PDF Links

• Switch to Link mode on the home screen.
• Paste a direct URL to a PDF file (e.g., https://arxiv.org/pdf/2605.06619).
• Click Translate to download and open the document.
• The app validates the URL, shows download progress, and handles errors gracefully.

Note: The URL must point directly to a PDF file. Web pages that embed PDFs are not supported.

Translation Settings

You can configure translation settings before opening a document, or adjust them at any time from the translator toolbar.

Source Language

Select the language of the original document. Available options include:

• Auto Detect — The app automatically identifies the source language. This works well for most documents.
• Specific language — Choose a specific source language for better accuracy, especially for scanned documents or less common languages.

Target Language

Select the language you want to translate into. Doco Translate supports a wide range of target languages, including:

Right-to-left languages (Arabic, Hebrew, Persian, Pashto, Urdu, Kurdish) are handled with layout direction awareness.

Translation Service

Choose which translation provider to use. Doco Translate supports three categories of services:

• Basic services — Google Translate, Microsoft Translate, Yandex Translate. No API key required.
• AI / LLM services — Gemini, OpenAI, Claude, DeepSeek, and more. Requires an API key.
• Local services — Ollama and LM Studio. Runs entirely on your machine.

See Services for a complete list and configuration guide.

Translating Pages

Once you open a PDF, Doco Translate processes it in two phases:

1. Parsing

The app analyzes the PDF structure page by page, extracting:

• Text paragraphs with position and formatting metadata
• Images, tables, and formulas
• Page dimensions and layout information

2. Translating

Each page is sent to the selected translation service. You can observe the process in real time:

• Pages display a loading indicator while translating.
• Translated text appears as soon as the service responds.
• A progress bar in the status bar shows overall completion.

Concurrent Translation

Doco Translate can translate multiple pages simultaneously for faster results. You can configure the maximum number of concurrent pages in Settings → Preferences → Max Concurrent Pages (default: 3).

Tip: For API-based services, higher concurrency means faster translation but may hit rate limits. For local services, concurrency depends on your hardware.

Retrying Failed Pages

If a page fails to translate (due to network errors, rate limits, or service issues):

1. A red error banner appears on the failed page with the error message.
2. Click Retry to re-translate the page with the same service.
3. Click the service selector next to Retry to switch to a different service for that page.
4. Use the Retry All Failed button in the status bar to retry all failed pages at once.

Image Translation

Doco Translate can translate text found in images within your PDF:

1. Enable Translate Images in the translation settings.
2. The app uses OCR to recognize text in images (pictures and tables).
3. Recognized text is sent to the translation service.
4. The translated image replaces the original in the reading view.

Note: Image translation requires a service that supports multimodal input (most AI/LLM services). Basic translation services do not support image translation.

Scanned Documents

For scanned PDFs (where text is embedded as images rather than selectable text):

1. Doco Translate automatically detects scanned documents.
2. A prompt appears asking you to specify the source language for better OCR accuracy.
3. The app uses OCR to extract text from each page before translating.

Tip: Always specify the source language for scanned documents. Auto-detection may be less accurate on OCR-extracted text.

Glossaries

Glossaries let you define preferred translations for specific terms, ensuring consistent terminology across your documents.

Creating a Glossary

1. Go to Settings → Glossary.
2. Click Add Glossary to create a new glossary.
3. Give it a name and optional description.

Adding Glossary Items

1. Open a glossary and click Add Glossary Item.
2. Enter the Source Text (the term in the original language).
3. Enter the Translated Text (your preferred translation).
4. Select the Target Language for this entry.

Using Glossaries

• Enable or disable individual glossaries using the toggle switch.
• When a glossary is enabled, Doco Translate automatically replaces matching source terms before sending text to the translation service.
• You can have multiple glossaries active simultaneously.

Importing and Exporting

• Export a glossary to a CSV file for backup or sharing.
• Import a CSV file to bulk-add glossary items.

CSV format: source_text,translated_text,target_language

Search

Use the search feature to find specific content within a translated document:

1. Click the Search button (magnifying glass icon) in the toolbar.
2. Enter your search term.
3. Choose to search in Source (original text) or Translation (translated text).
4. Navigate between results using the arrow buttons.
5. The view automatically scrolls to the matching page.

Reloading

If you need to re-parse and re-translate a document (e.g., after changing the source language):

1. Click the Reload button (circular arrow icon) in the toolbar.
2. Confirm the action in the dialog.
3. The app discards all current translations and re-parses the PDF from scratch.

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