OCR Recognition Issues - Troubleshooting and Solutions

## Common Recognition Issues Inaccurate OCR recognition is the most common problem users encounter. This guide helps you analyze causes and find solutions. ## Issue 1: Incorrect Character Recognition ### Possible Causes - Blurry or unclear image - Font too small or unusual - Excessive image compression - Low contrast between text and background ### Solutions 1. Use higher resolution images 2. Ensure sharp focus when capturing 3. Use PNG format to avoid compression loss 4. Adjust image contrast and brightness ## Issue 2: Missing Text ### Possible Causes - Text obscured (stamps, watermarks) - Edge text cropped out - Text color too light - Severe background interference ### Solutions 1. Ensure all text is fully captured 2. Crop obstructions or recognize in sections 3. Increase image contrast 4. Use solid color background when photographing ## Issue 3: Garbled Output ### Possible Causes - Image severely tilted or rotated - Incorrect text orientation - Wrong language selection - Special characters or symbols ### Solutions 1. Rotate and correct image orientation 2. Ensure text is horizontally aligned 3. Select correct recognition language 4. Special symbols may need manual input ## Issue 4: Lost Formatting ### Possible Causes - OCR primarily extracts text content - Complex layouts hard to preserve - Table structures difficult to recognize ### Solutions 1. Accept plain text output, format manually 2. Recognize in sections to maintain order 3. Export table content for later formatting ## Image Quality Optimization ### Resolution Requirements - Recommend 300 DPI or higher - Text height at least 20 pixels - Avoid over-enlarging blurry images ### Lighting Adjustment - Adequate, even lighting - Avoid strong reflections - Avoid shadows on text ### Angle Correction - Shoot as perpendicular as possible - Tilt angle under 15 degrees - Use software to correct skewing ### Format Selection - PNG recommended (lossless) - JPG: maintain quality settings - Avoid multiple compression cycles ## Optimization Tips by Scenario ### Scanned Documents - Scan at 300 DPI - Use grayscale or black/white mode - Ensure paper is flat ### Phone Photos - Use document scan mode - Keep phone stable - Wait for focus to complete ### Screenshots - Use native resolution - Avoid scaling before capture - Save as PNG format ### Handwritten Text - Write as neatly as possible - Use dark-colored pen - Maintain character spacing ## Post-Recognition Proofreading ### Common Error Types - Similar character confusion (e.g., 0/O, 1/l) - Number and letter mix-ups - Punctuation errors - Spacing and line break issues ### Proofreading Tips 1. Read through results checking meaning 2. Focus on numbers and proper nouns 3. Use find-replace for batch corrections 4. Keep original image for reference ## Special Situations ### Multiple Languages - Ensure selected languages are supported - Chinese-English mixed text usually works well - Minor languages may need special handling ### Vertical Text - Some OCR supports vertical recognition - Can rotate image before recognition - Manually adjust text order if needed ### Artistic Fonts - Artistic fonts are difficult to recognize - Manual input recommended - Or find original text source ## FAQ ### Q: Why do results vary for the same image? A: May be due to network transmission affecting quality, or server model updates. Use original high-resolution images. ### Q: Recognition is very slow? A: Check image size. Large images slow processing. Recommend compressing to under 5MB. ### Q: Can PDF files be recognized? A: Yes, but convert PDF to images first. For text-based PDFs, you can copy text directly. ### Q: How to ensure quality in batch processing? A: Ensure consistent image quality, use same capture/scan settings, spot-check results. ## Summary OCR accuracy is affected by multiple factors. By optimizing image quality, selecting correct settings, and necessary manual proofreading, you can achieve satisfactory results. When problems occur, start by checking image quality - this often solves most issues.