OmniDocHow to modify the scanned document: first identify the text and then edit it
The scanned copy is essentially a picture and cannot be directly altered. This article explains why OCR recognition should be done first, and gives specific steps to complete recognition, modification, verification and export using OmniDoc desktop.
Key points of this article
- The scanned image is essentially an image; opening it directly for editing often only allows viewing without modification, requiring OCR to generate selectable text first.
- Before recognition, try selecting a text segment; if you can select it, it means there is already a text layer; If it can't be selected, you need to recognize it first.
- OCR is machine recognition; numbers, dates, amounts, and proper nouns are prone to errors, so each item must be checked before and after modifications.
- After text modifications are completed, it can be exported to formats such as Word, making it easier to continue extensive editing or relayout.
Many people get a scanned contract, an old paper or an electronic version of a paper report and want to correct a few typos or fill in a new date, but find that nothing can be changed by clicking on it with the cursor. This is usually not a problem with the software, but rather that the PDF itself is a picture, and the text is just "drawn" on the page, and the editor cannot find characters that can be replaced.
This article is written for general readers, students and office workers who need to modify scanned documents. After reading, you will know: why scanned documents need to recognize text first, which situations can be modified directly, how to complete the whole process of "identification, modification, verification, and export" on the OmniDoc desktop, and what to do when the recognition results are wrong.
How to modify the scanned document? One sentence conclusion
To modify the scanned document, first use OCR to identify the text on the image into an editable text layer, and then enter editing; if the text can already be selected in the file, this step is not needed.
| your situation | Recommended practices | reason |
|---|---|---|
| Ability to select text on the page | Directly edit paragraph text | The file already has a text layer, and the editor can find replaceable characters |
| When selected, only the full page picture can be framed. | First, perform OCR on the pages that need to be modified, then edit them | The scanned copy is an image and must be written into text |
| Only change a few words on individual pages | Only identify relevant pages and modify them section by section. | Reduce the workload of identification and verification |
| Rewrite in large sections or continue typesetting | Export to Word format after recognition | Rewriting large paragraphs is more convenient in word processing software |
| Just sign, date or black out | No need to identify, just use the corresponding function | These operations target page placement and do not rely on text content |
Before you start: Confirm these points first
- Confirm that the document is indeed a scan. Open the PDF and drag a section of text with the mouse. If it can be selected and highlighted, it means there is a text layer; it can only frame the entire area, which is the picture. This step determines whether you want to identify it, and it can also avoid unnecessary work.
- Check scan quality. Pay attention to whether the page is skewed, gray, shadowed, or whether the writing is blurred. Pages with poor quality will have significantly more recognition errors. It is recommended to rescan or photograph them flatter before processing.
- Clear the scope of modification. Only a few changes will be made, and only relevant pages will be recognized; a large section will need to be rewritten, and it will be more labor-saving to export the entire page to Word after recognition. Set the scope first so that the operation will not be repeated.
- Back up original files. Modifications will generate a new file, and an unmodified original will be retained so that you can refer to it when making mistakes and have a basis when someone asks about the content.
- Allow time for verification. OCR will cause misreading, especially numbers, decimal points, names, units and table lines. Important documents cannot be considered to be completely correct if they are identified once, and the originals need to be compared item by item.
Steps to identify and modify scans in OmniDoc desktop
- Visit download.omnidoc.top to download the OmniDoc desktop client, install and open it according to your system. It supports Windows, macOS, and Linux.
- Open the scanned PDF you want to modify, flip to the page you want to modify, and confirm that the page numbers and content are correct.
- In the editor, select OCR recognition to perform text recognition on scanned pages. When modifying only some pages, select only those pages to save time.
- After recognition is complete, try selecting a segment of text. If the text is selected, the recognition is valid.
- Find the paragraph you want to modify and directly rewrite the text. It is recommended to change only one part at a time, then read the context once to ensure the sentences are smooth and consistent throughout.
- If you need to sign, fill out forms, shade sensitive information, or perform page operations (insert, delete, rotate, rearrange, merge, split), all are done in the same editor.
- Save the revised PDF. If you want to continue making major edits, you can export them to Word or Excel format and adjust them in the corresponding software.
- Open the original and compare the modified file side by side, checking page by page for any omissions or errors.
If your goal is simply to translate the scanned copy into other languages, OmniDoc also supports directly uploading scanned PDF translations without needing to modify them in the editor first. The translation results also need to verify important content.
After completion, check each item one by one
| Inspection items | How to see it | What should you do if there's a problem? |
|---|---|---|
| Check whether the text recognition is correct | Read paragraph by paragraph against the original, focusing on numbers, dates, amounts, and proper nouns | Correct it directly in the editor and review the page again |
| Paragraph order and columns | Check if the multi-column pages are serialized, and if the title and body text are misaligned | When the order is confusing, export Word to adjust paragraphs or re-identify the page |
| Tables and formulas | Check whether rows and columns are aligned and whether formula symbols are missing | For complex tables and formulas, it is recommended to manually correct them against the originals; do not rely solely on recognition results |
| Stamp and signature area | Confirm that the modification does not overwrite or damage the original seal or signature | If affected, keep that part of the original and only adjust the text in the modified version |
| Page count and completeness | Compare the number of pages with the original, and check if there are any missing pages | If you miss a page, go back to step two and select page handling again |
❓ Frequently Asked Questions (FAQ)
1. How do you get a scan?
If you only have paper documents and want to get a processable electronic version first, you can use a scanner or a phone to take photos and organize them into PDFs. When shooting, try to keep the page flat, ensure even lighting, and keep all four corners intact, which will reduce future recognition errors.
2. What should I do if the text is garbled or missing after recognition?
First, check whether the original is blurry, tilted, or shadowed—this is a common cause of identification errors. You can re-scan or photograph the page to re-identify it; If only a few characters are incorrect, you can manually correct them directly in the editor.
3. Can the text on the scanned image be directly changed?
If the text belongs to the image itself, such as slogans on posters or annotations in charts, OCR may not be able to fully recognize it. A common approach is to use image editing tools to modify and then return to the document, or re-enter the relevant text as is.
4. Can the original layout be retained after modification of the scan?
The degree of layout retention depends on the complexity of the page itself. Simple text pages are usually well preserved, while pages with multiple columns, tables, and formulas need to be checked page by page and adjusted after exporting to Word if necessary.
📝 Summary
The scanned document is essentially an image. If you want to modify the text inside, the safer order is to first use OCR to identify the editable text, then modify, verify, and export. The key during the process is to first determine the file type, ensure scan quality, and compare the recognition results against the original item by item.
