adding text to a pdf using PyMuPDF

Question

I'm trying to add text to a pdf by opening the PDF, adding a text box, and saving it. When I run the code, nothing happens. on the desktop, it shows the file has been updated, but there is no text displayed on it.

Here's the code:

import fitz 
doc = fitz.open("/Users/khaylablack/Desktop/participant_certificate.pdf")           
page = doc[0]                         # choose some page
rect = fitz.Rect(50, 100, 200, 200)   # rectangle (left, top, right, bottom) in pixels

text = "absolutely not"

rc = page.insertTextbox(rect, text, fontsize = 48, # choose fontsize (float)
                   fontname = "Times-Roman",       # a PDF standard font
                   fontfile = None,                # could be a file on your system
                   align = 1)                      # 0 = left, 1 = center, 2 = right

#doc.saveIncr()   # update file. Save to new instead by doc.save("new.pdf",...)
doc.save("/Users/khaylablack/Desktop/watermarked_participant_cert.pdf")

Answer 1

When using insertTextbox() method, you have to be sure that the rect you create can contain the text, because if not, you will end up with no text displayed. One way to do this, is checking the text's lenght for your implementation, like this:

text = "absolutely not"
text_lenght = fitz.getTextlength(text, fontname="Times-Roman", fontsize=48))

text_lenght will be 270.67.

But the rect's width you have is just 150 (200-50). Also, even changing the rect's width won't work, because it's still too short, so you need also to increase it's height. Another thing you can do is just change the fontsize you're using. These two alternatives will look like this:

• Alternative 1, bigger rect:

fontsize_to_use = 48

text = "absolutely not"
fontname_to_use = "Times-Roman"

text_lenght = fitz.getTextlength(text, 
                                 fontname=fontname_to_use, 
                                 fontsize=fontsize_to_use)

rect_x1 = 50
rect_y1 = 100
rect_x2 = rect_x1 + text_lenght + 2  # needs margin
rect_y2 = rect_y1 + fontsize_to_use + 2  # needs margin


rect = (rect_x1, rect_y1, rect_x2, rect_y2)

## Uncomment if you wish to display rect
# page.drawRect(rect,color=(.25,1,0.25)) 

rc = page.insertTextbox(rect, text,
                        fontsize=fontsize_to_use,
                        fontname=fontname_to_use,
                        align=1)

Alternative 2, smaller fontsize:

text = "absolutely not"
fontname_to_use = "Times-Roman"

rect_x1 = 50
rect_y1 = 100
rect_x2 = 200
rect_y2 = 200

rect_width = rect_x2 - rect_x1
rect_height = rect_y2 - rect_y1

rect = (rect_x1, rect_y1, rect_x2, rect_y2)

fontsize_to_use = rect_width/len(text)*2  # *2 just because 1pt is too small for a char. It mantains a good ratio for rect's width with larger text, but behaviour is not assured.

## Uncomment if you wish to display rect
# page.drawRect(rect,color=(.25,1,0.25))

rc = page.insertTextbox(rect, text,
                        fontsize=fontsize_to_use,
                        fontname=fontname_to_use,
                        align=1)

Note: rc is the unused rectangle height, it can also be negative, in your case it was -5.59, which means text was exceeding rect's height.

Answer 2

I had the same problem and, thanks to @JorjMcKie, I was able to solve it adding the call

page.clean_contents(False)

after the load of the page.

From the pyMuPDF official documentation:

Page.clean_contents(sanitize=True)

• Changed in v1.17.6

PDF only: Clean and concatenate all contents objects associated with this page. “Cleaning” includes syntactical corrections, standardizations and “pretty printing” of the contents stream. Discrepancies between contents and resources objects will also be corrected if sanitize is true. See Page.get_contents() for more details.

Changed in version 1.16.0: Annotations are no longer implicitly cleaned by this method. Use Annot.clean_contents() separately.

Parameters: sanitize (bool) – (new in v1.17.6) if true, synchronization between resources and their actual use in the contents object is snychronized. For example, if a font is not actually used for any text of the page, then it will be deleted from the /Resources/Font object.

Warning:

This is a complex function which may generate large amounts of new data and render old data unused. It is not recommended using it together with the incremental save option. Also note that the resulting singleton new /Contents object is uncompressed. So you should save to a new file using options “deflate=True, garbage=3”.

Answer 3

Have you installed both pymupdf and fitz? If not try running these in your command prompt.

pip install pymupdf
pip install fitz