AI Translator Functional Boundaries
This document describes the functional boundaries, known formatting issues, and limitations for translating various types of documents.
1. PDF Documents (Non-scanned)
Unsupported document types
- Design documents (drawings, posters)
- Right-to-left layout documents (such as Arabic)
- Vertical text
- Documents using Type3 fonts
Possible issues
| Issue | Impact | Recommendation |
|---|---|---|
| Formula paragraphs overlap | Formula areas may not display properly | Refer to the original text for understanding |
| Inaccurate recognition of small paragraphs | Author information, quotations, etc. may be omitted | Manually supplement important information |
| Charts are not translated | Text inside charts remains in the original language | If chart translation is needed, handle it manually |
| Underlines disappear | Formatting effects are lost | Add them manually after download |
| Drop cap effect is lost | Layout style is simplified | Mainly affects visual appearance, not content |
Download format description
Default option:
- Only supports downloading in PDF format
Optional configurations (must be enabled by an administrator):
-
Built-in converter (free):
- Can be converted to Word (.docx) format
- ⚠️ Text loss or blank pages may occur
- Suitable for scenarios requiring simple editing
-
Adobe service (paid):
- High conversion quality with good format retention
- Requires separate service purchase
- Suitable for scenarios with strict formatting requirements
Special notes:
- Scanned documents do not support docx conversion
- PDFs converted from PPT and then converted to docx may have formatting issues
Scanned PDF
Applicable scenarios
- ✅ Scanned paper documents
- ✅ Well-formatted document photos
- ✅ Clear scans of contracts and reports
Unsuitable scenarios
- ❌ Scans with watermarks
- ❌ Blurry photos
- ❌ Handwritten documents (low recognition rate)
- ❌ Partial vertical text within pages
Possible issues
| Issue | Impact | Recommendation |
|---|---|---|
| Slight reduction in image clarity | File size is reduced by 60-70%, edges may be slightly blurred | Contact the administrator if high-definition output is needed |
| Text in narrow areas is cropped | Translated text in extremely narrow positions may not display completely | Refer to the original text for comparison |
| Table text is truncated | May be cropped when cell space is insufficient | Font size has already been automatically reduced as much as possible |
| Inaccurate handwriting recognition | Content with low confidence will be skipped | Handwritten parts require manual processing |
Special features
- Automatic orientation detection: Supports 0°/90°/180°/270° rotation with automatic correction
- Bilingual output: Can generate both translation-only and bilingual comparison versions
- Pagination processing: Documents over 50 pages are automatically processed in batches to ensure stability
Technical requirements
- OCR service: Azure OCR is recommended (more accurate recognition)
- If not configured, RapidOCR will be used automatically (lower quality)
3. Word Document Translation
Applicable scenarios
- ✅ Contracts, agreements
- ✅ Proposals, reports, papers
- ✅ Operation manuals, training materials
Possible issues
| Issue | Impact | Solution |
|---|---|---|
| Pagination changes | Different translation lengths cause page shifts | ✅ Normal phenomenon, manually adjust page breaks |
| Text box overflow | Text may exceed fixed-size boxes | ✅ Adjust the text box size or reduce the font size |
| Table of contents page number misalignment | Page numbers do not match actual positions | ✅ Right-click the table of contents → "Update Field" → "Update entire table" |
Feature description
Supported for translation
- ✅ Main body content
- ✅ Heading styles
- ✅ Table text
- ✅ SmartArt text content (styles may be simplified)
Content not translated
- ❌ OLE embedded objects (embedded Excel, Visio, etc.)
- ❌ Revision marks and comments
- ❌ Field codes (dates, cross-references, etc.)
Notes
- Online preview is not currently supported after translation; download to view
- Complex SmartArt styles (gradients, special effects, etc.) may be simplified
4. Excel Document Translation
Applicable scenarios
- ✅ Data tables, lists
- ✅ Statistical reports
- ✅ Process description tables
File opening prompt
A "repair needed" prompt may appear when opening for the first time:
- ✅ This is normal
- ✅ Click "Yes" or "Repair"
- ✅ Content will not be lost
Reason: Complex styles or charts may trigger Excel format validation when written back
Intelligent skip rules
The system automatically skips content that does not need translation:
- 🔢 Formulas: Cells starting with
=remain unchanged - 📅 Dates: Date-type cells are not translated
- 🔢 Pure numbers: To avoid damaging data
- 📏 Merged cells: Only the top-left content is translated
Functional limitations
| Content type | Translated | Description |
|---|---|---|
| Cell text | ✅ Yes | Main content |
| Worksheet names | ✅ Yes | Maximum 31 characters, cannot contain special symbols |
| Formulas | ❌ No | Formula logic remains unchanged |
| Charts | ❌ No | May be lost |
| Macros (VBA) | ❌ No | Functionality is not affected |
| SmartArt / shape text | ❌ No | - |
| Headers and footers | ❌ No | May be lost |
| Comments | ❌ No | May be lost |
Worksheet name rules
- Maximum 31 characters (Excel system limitation)
- Excess parts are automatically truncated
- Cannot contain:
/ \ ? * [ ] :
Notes
- Formula calculation results will only display after reopening the file
- Charts in files may be lost after translation
- Complex conditional formatting may be simplified
5. PowerPoint Document Translation
Applicable scenarios
- ✅ Presentations
- ✅ Training courseware
- ✅ Product introductions
Possible issues
| Issue | Impact | Solution |
|---|---|---|
| Text overflows text box | Translation length exceeds boundaries | ✅ Reduce font size or adjust the text box |
| Grouped shapes shift | Text positions in complex groups may be slightly adjusted | ✅ Ungroup and adjust manually |
| Abnormal font display (garbled text) | Target language font is incompatible | ✅ Enable the "Font Compatibility" option (recommended) |
Feature description
Supported for translation
- ✅ Slide body text
- ✅ Titles and subtitles
- ✅ Text box content
- ✅ Table text
- ✅ SmartArt text (with standard structure)
- ✅ Chart titles, axis titles, legends
- ✅ Notes page content
Content not translated
- ❌ Section names (only content visible during slideshow is translated)
- ❌ Comments
- ❌ Embedded video/audio
- ❌ Complex third-party embedded charts
Content not affected
- ✅ Animation effects
- ✅ Transition effects
- ✅ Hyperlinks
Font compatibility option (recommended)
Background:
- PPT font compatibility is relatively weak
- Garbled text may appear after translation
Feature description:
- When the target language is Chinese, Japanese, or other East Asian languages
- Automatically replaces fonts in regular text boxes and tables
- Chinese is automatically replaced with "Microsoft YaHei"
Whether to enable:
- ✅ Recommended to enable: Automatic handling, saves time and effort
- ❌ Do not enable: Fonts at garbled positions need to be replaced manually
Notes
- Online preview is not currently supported after translation; download to view
- If the translation is longer than the original, it is recommended to check text box sizes
6. General Limitation Notes
Common characteristics across all formats
1. Translation length changes
-
Length differences across languages:
- Chinese → English: usually 20-50% longer
- English → Chinese: usually 30-40% shorter
- Chinese → German: usually 40-60% longer
-
Possible resulting issues:
- Text box overflow
- Pagination changes
- Incomplete display of text in table cells
2. Automatic skip rules
- ✅ Pure numeric content (e.g.: 12345)
- ✅ Pure symbol content (e.g.: ***、---)
- ✅ Formulas and dates
- ✅ Content with OCR confidence below 50% (scanned documents)
3. Terminology consistency
- Supports custom glossaries
- Translation quality is related to model capability
- Mismatches may occur when model capability is weaker
4. Format retention mechanism
- By default, formatting at the beginning position of paragraphs is retained
- Formatting is not preserved precisely for every character
- Possible outcome: some formatting may be lost or may not follow the translated text
Example:
Original: This is a paragraph containing 【bold】 and *italic* text
Translation: It may all be displayed in plain formatting
5. Long text processing
- Extra-long single paragraphs are automatically split for translation
- In rare cases, transitions across segments may be less natural
6. Translation timeout notes
Reference data (using GPT-4 as an example):
| Document character count | Estimated time | Recommendation |
|---|---|---|
| Within 100,000 characters | 5-15 minutes | ✅ Translate directly |
| 100,000-300,000 characters | 15-40 minutes | ✅ Translate directly |
| 300,000-500,000 characters | 40-70 minutes | ⚠️ Timeout may occur, segmenting is recommended |
| Over 500,000 characters | More than 70 minutes | ❌ Recommended to split before uploading |
Timeout handling:
- Documents over 500,000 characters are recommended to be split
- Translate in batches and then merge
7. Best Practice Recommendations
Before translation
1. Document preparation
- ✅ Clean up unnecessary formatting and styles
- ✅ Delete pages that do not need translation
- ✅ Check whether the document is corrupted
- ✅ Ensure scanned documents are clear
2. Choose the appropriate format
- Pure text content: Prefer Word
- Contains a large amount of data: Use Excel
- Presentation materials: Use PPT
- Paper documents: Scan and use scanned document mode
3. Handling very large files
- Documents over 500,000 characters are recommended to be split
- Divide into multiple files by chapter or topic
- Merge after translation
During translation
1. Option configuration
- PPT translation: It is recommended to enable "Font Compatibility"
- Scanned documents: Choose "Bilingual Output" for easier verification
- Terminology-sensitive content: Configure a glossary
2. Be patient
- Large file translation takes time
- Avoid repeated submissions
- You can switch to background execution
After translation
1. Required checks
- ✅ Open and review with the corresponding software (Excel/Word/PowerPoint)
- ✅ Click "Yes" if prompted with "repair needed"
- ✅ Word table of contents needs to be updated (right-click → Update Field)
- ✅ Check whether key terminology is accurate
2. Formatting adjustments
- ✅ Check whether text boxes overflow
- ✅ Adjust pagination positions
- ✅ PPT font size may need to be reduced
- ✅ Excel column widths may need adjustment
3. Content verification
- ✅ Compare important paragraphs against the original
- ✅ Confirm that numbers and dates have not been changed
- ✅ Ensure formula calculation results are correct (Excel requires reopening)