How to batch remove content from fixed areas of PDFs? Clean up multiple files by page number and coordinates

When you need to remove character images, old materials, text blocks, or page decorations at the same position from a large number of PDFs, you can use a batch processing method that defines a rectangular area by coordinates. This article explains, with reference to the actual interface, how to use HeSoft Doc Batch Tool to import multiple PDFs, set all pages, odd/even pages, or custom page ranges, choose centimeters, inches, points, or percentages as the unit of length, and precisely locate the area using the left distance, top distance, region width, and height, helping users reduce the repetitive work caused by page-by-page editing.

When there are only a few PDF files, manually modifying them may not seem difficult; however, when the same deletion action needs to be repeated across dozens of files and hundreds of pages, manual operation exposes problems such as low efficiency, inconsistent standards, and easily missed pages. In particular, character images, explanatory text, old template decorations, or other elements at fixed positions on pages should not be opened and deleted one by one simply because the files are different, as this is not an ideal way of working.

For PDFs with consistent structures, a rectangular area can be defined by coordinates, allowing office software to batch-clear the content within that area. HeSoft Doc Batch Tool provides the "Delete content in a specified PDF area" function, which can import multiple PDFs at once and also control the page range and rectangle size to process. This article focuses on explaining the coordinate logic, operation flow, and inspection methods before and after batch processing.

Applicable scenarios: what problems can be solved by deleting PDF content by coordinates

The so-called coordinate-based deletion means processing content according to its position on the page, rather than relying on specific text or image names. As long as multiple files use the same template and the target object's position on the page is stable, they can share one set of parameters.

Typical applications include:

• Deleting character images or illustrations at fixed positions on pages of multiple e-textbooks.
• Cleaning up old sidebars, prompt blocks, or explanatory areas in a batch of PDF reports.
• Removing text, graphics, and template elements that repeatedly appear at page edges.
• Processing only fixed areas on odd or even pages to accommodate alternating left-right page layouts.
• Deleting content within a certain range only on the first few pages, last few pages, or specified page numbers.

This function is most suitable for files with unified layouts. If the target object's position differs in each PDF, or if the layout within the same file often changes, the task needs to be split and cannot simply be covered by one large rectangle, otherwise the main text may be damaged.

Effect preview: comparison before and after fixed-area cleanup

Page state before processing

In the sample PDF, there is a character image slightly to the left of the middle of the page, a green-background main text area on the right, a chapter title at the top, and a page number at the bottom. What needs to be deleted in this operation is the character image, rather than cropping the left half of the page.

From the page structure, there is a certain gap between the character image and the main text on the right, so it can be covered separately by a rectangular area. For other PDFs using the same template, as long as the image position has not shifted significantly, the same coordinates can be used.

Page state after processing

After execution, the character image has been removed from the page, and the original position becomes blank; the main text on the right, the title at the top, and the page number at the bottom remain. The red arrow on the page has not been completely cleared because it lies outside the target rectangle.

This result shows that the rectangle parameters determine both "what to delete" and "what to keep". During actual acceptance checks, you should simultaneously check whether the target object has completely disappeared and whether there is any accidental deletion near the edges of the area.

Operation steps: creating a PDF area-deletion batch task

Step 1: Open the PDF content processing function

Enter HeSoft Doc Batch Tool , click "PDF Tools" in the left function bar, and then select "Content Processing" at the top of the page. Find "Delete content in a specified PDF area" in the tool list and click to enter.

From the interface description, it can be determined that the processing target of this function is a specified rectangular area in PDF files, and it is suitable for applying the same deletion rules to multiple files. When selecting the function, do not confuse it with needs such as deleting entire pages or deleting all images.

Step 2: Add files and check task records

After entering the function, you are currently at the "Select records to process" stage. The top of the interface provides two entry points: "Add files" and "Import files from folder". The former is suitable for selecting several specific PDFs, while the latter is suitable for centrally adding materials from the same directory.

The example has already added 1.pdf, 2.pdf, 3.pdf, and 4.pdf, for a total of 4 records. The list includes name, path, extension, creation time, and modification time, making it convenient for users to confirm the file source before formal processing.

The expected result of this step is that only PDFs that truly need to be processed according to the same rules remain in the task list. If a file has a different page size, or the target content is not in the same position, it should be removed first and processed separately later in its own task. After completing the check, click "Next".

Step 3: Set the page number processing range

The second stage is "Set processing options". First select the processing range. The options visible in the interface include all pages, the first few pages, the last few pages, odd pages, even pages, and custom.

The page range affects which pages participate in area deletion:

• When the target element appears on every page, select all pages.
• When it appears only on the cover or preface, select the first few pages.
• When it appears only at the end of the document, select the last few pages.
• In double-sided layout, when the target is on one side of the pages, use odd pages or even pages.
• When only a few scattered pages need to be cleaned, consider a custom range first.

Choosing the page range correctly can reduce unnecessary modification of unrelated pages. Even if the rectangle position on a certain page appears blank, the processing range should not be expanded when it is not necessary.

Step 4: Select the length unit

In the length unit section, you can choose centimeters, inches, points, or percentage. The example uses percentage. The unit determines how the following four values are interpreted, so it should be determined before entering coordinates.

If all PDF pages have exactly the same size, orientation, and proportions, you can choose an absolute unit based on actual measurement; if page sizes may vary slightly but the target object in the template maintains its relative position, percentage is usually more convenient for unified description. However, there is no absolute advantage or disadvantage in unit selection, and the final choice should still be based on sample results.

Step 5: Determine the rectangle from the upper-left corner of the page

The yellow prompt in the interface clearly states that the rectangular area starts from the upper-left corner of the page. To fully define the rectangle, you need to enter the distance from the left side of the page, the distance from the top of the page, the area width, and the area height.

The parameters in the screenshot example are 20.00, 40.00, 20.00, and 60.00 respectively, with percentage selected. When understanding these four items, you can follow this order:

1. Move right from the upper-left corner of the page by the value of "Distance from the left side of the page".
2. Then move down by the value of "Distance from the top of the page" to determine the upper-left corner of the rectangle.
3. Extend "Area width" to the right from that point.
4. Extend "Area height" downward from that point, finally forming the deletion range.

The purpose of the settings is to make the target image, text, or graphic lie as completely as possible inside the rectangle while avoiding the main text and other elements that need to be retained. For objects close to the main text frame, the boundaries should be handled with particular care.

Step 6: Configure the save location and execute the task

After completing the page range and area settings, click "Next" at the bottom to enter "Set save location" in the workflow, and then proceed to "Start processing". When saving the results, it is recommended to use a separate directory and keep the original PDFs for convenient comparison and readjustment.

The expected result after the task is completed is that, on pages in the current file list that meet the page range conditions, the content within the specified rectangular range is uniformly deleted. Because different PDFs may have slight layout differences, you should randomly open multiple files for inspection after processing.

Practical methods for improving coordinate accuracy

First conduct a small-scale test with a representative file

Do not execute the final task on all files the first time. You can choose a PDF copy with the most representative page structure, set the area, and then view the result. Confirm that the target content is completely deleted and that the adjacent main text is unaffected before applying it to other files.

Adjust parameters according to the direction of remaining content

If there is still residue on the left side of the target object, you may need to reduce the distance from the left side of the page, or appropriately increase the width; if there is residue on the right side, you can increase the area width; if the top is not fully deleted, adjust the starting point upward; if there is residue at the bottom, check whether the area height is sufficient.

Do not use an oversized rectangle to cover layout differences

When the target position in some PDFs is more to the left and in others more to the right, directly enlarging the rectangle may cover all targets, but it may also delete more normal content. In this case, the files should be split into two or more groups according to different templates.

Check page orientation and size separately

Landscape pages and portrait pages have different coordinate relationships, and A4 pages and pages of other sizes may also deviate when absolute units are used. Before batch processing, you can first organize files according to page orientation, paper specification, and template version, and then set parameters separately.

Common problems and precautions

What content within the rectangular area will be processed?

The function is described as deleting all content within the specified rectangular area, so when setting it you cannot focus only on the target image. If there is text, borders, or graphics that still need to be retained within the same range, these objects should also be included in the risk assessment.

Why was only part of the target image deleted?

Usually this is because the rectangle does not completely cover the image, or the image has shadows, edges, or decorations that extend beyond the main body. The starting point, width, and height should be fine-tuned according to the position of the residue.

Why are the same parameters inconsistent in position across different PDFs?

It may be due to differences in page size, rotation direction, cropping range, or template layout. It is recommended to compare the page structures of these files and process the inconsistent files separately, rather than continuing to use the same parameters.

Can only specified pages be processed?

You can select the first few pages, last few pages, odd pages, even pages, or a custom range from the processing range provided in the interface to reduce the participation of unrelated pages in the task.

Is area deletion equivalent to page cropping?

From the example effect, the overall page size and other content are still retained, and only the character image in the target area disappears, so it is not the same processing approach as cropping the entire page edge.

Why is spot checking always necessary before and after processing?

Batch functions can reduce repetitive work, but the same batch of files may contain a small number of special pages. Checking the first page, middle pages, last page, and different files helps to promptly discover problems such as coordinate offset, content residue, or an overly large range.

File management suggestions for batch processing PDFs

To make it easier to track results, you can put the original PDFs into one directory before execution and save the processed results to another directory. When there are many files, you can also group them by template, page orientation, or task batch. In this way, once parameters need to be modified, you can quickly find the corresponding original files and process them again.

Before formal delivery or archiving, you should confirm that the result files can be opened normally, that the page count matches the original files as expected, and check key main text, titles, page numbers, and graphics. Batch processing improves the efficiency of repetitive operations, but quality inspection still cannot be omitted.

Summary

The core of batch-removing content from fixed PDF areas is not repeatedly executing deletion, but establishing an accurate and reusable set of page and coordinate rules. HeSoft Doc Batch Tool can add multiple PDFs to the same task, use the upper-left corner of the page as the starting point, define the rectangle through left distance, top distance, area width, and area height, and then complete saving and processing in a unified manner.

If you need to clean up a large number of PDFs with the same layout, you can first select a copy for testing: enter the content processing function in PDF Tools, import the sample, select the actual page range, determine the length unit, and fill in the rectangle parameters. After confirming that the before-and-after comparison meets the requirements, batch-import and execute the same type of files, thereby reducing the repetitive work caused by editing files one by one and checking pages one by one.