[Python] Custom background image positioning within stamp field using pyHanko python library

I’ve been testing the pyHanko library for digitally signing PDF documents. The digital signing process went smoothly using a .pfx file, and the signature is visible in Adobe Acrobat.

However, I’ve encountered an issue with positioning the visible stamp. While my image appears, I can't figure out how to adjust its placement within the field to avoid overlapping with the text.

If anyone has experience with this library, I would greatly appreciate your guidance.

Here is the relevant part of my code:

from pyhanko.pdf_utils.incremental_writer import IncrementalPdfFileWriter
from pyhanko.sign import signers
from pyhanko.sign.fields import append_signature_field, SigFieldSpec
from pyhanko.sign.signers import PdfSigner, SimpleSigner
from pyhanko.stamp import TextStampStyle
from pyhanko.pdf_utils.images import PdfImage
from pyhanko.pdf_utils.text import TextBoxStyle

signer = SimpleSigner.load_pkcs12(pfx_file='certificate.pfx')

with open('test.pdf', 'rb') as doc:
writer = IncrementalPdfFileWriter(doc)

# Define a signature field to sign
append_signature_field(
writer,
sig_field_spec=SigFieldSpec(
"Signature1", # Field name
box=(150, 100, 350, 200) # Signature box position
)
)

# Load the background image
background_image = PdfImage("signature.jpg")

# Define the stamp style without border
stamp_style = TextStampStyle(
border_width=0,
background=background_image,
stamp_text="Approved by: John X\non %(ts)s", # Add custom text with newline
timestamp_format='%d.%m.%Y %H:%M:%S %Z', # Format for the timestamp
background_opacity=0.5, # Set the opacity (0.0 to 1.0)
text_box_style=TextBoxStyle(font_size=9, border_width=0) # Set the font size
)


# Perform the signing process
with open('signed_test.pdf', 'wb') as out_file:
PdfSigner(
signers.PdfSignatureMetadata(
field_name='Signature1',
reason="Document approved",
location="New York"
),
signer=signer,
stamp_style=stamp_style
).sign_pdf(
writer,
output=out_file
)

print("PDF signed successfully and saved as 'signed_test.pdf'")`


I tried to follow documentation on https://pyhanko.readthedocs.io/en/0.4.0/api-docs/pyhanko.stamp.html but didn't figure it how as there is no example.

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