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"""
This is a demo script using PyMuPDF's Story class to output text as a PDF with
a two-column page layout.
The script demonstrates the following features:
* Layout text around images of an existing ("target") PDF.
* Based on a few global parameters, areas on each page are identified, that
can be used to receive text layouted by a Story.
* These global parameters are not stored anywhere in the target PDF and
must therefore be provided in some way.
- The width of the border(s) on each page.
- The fontsize to use for text. This value determines whether the provided
text will fit in the empty spaces of the (fixed) pages of target PDF. It
cannot be predicted in any way. The script ends with an exception if
target PDF has not enough pages, and prints a warning message if not all
pages receive at least some text. In both cases, the FONTSIZE value
can be changed (a float value).
- Use of a 2-column page layout for the text.
* The layout creates a temporary (memory) PDF. Its produced page content
(the text) is used to overlay the corresponding target page. If text
requires more pages than are available in target PDF, an exception is raised.
If not all target pages receive at least some text, a warning is printed.
* The script reads "image-no-go.pdf" in its own folder. This is the "target" PDF.
It contains 2 pages with each 2 images (from the original article), which are
positioned at places that create a broad overall test coverage. Otherwise the
pages are empty.
* The script produces "quickfox-image-no-go.pdf" which contains the original pages
and image positions, but with the original article text laid out around them.
Note:
--------------
This script version uses just image positions to derive "No-Go areas" for
layouting the text. Other PDF objects types are detectable by PyMuPDF and may
be taken instead or in addition, without influencing the layouting.
The following are candidates for other such "No-Go areas". Each can be detected
and located by PyMuPDF:
* Annotations
* Drawings
* Existing text
--------------
The text and images are taken from the somewhat modified Wikipedia article
https://en.wikipedia.org/wiki/The_quick_brown_fox_jumps_over_the_lazy_dog.
--------------
"""
import io
import os
import zipfile
import pymupdf
thisdir = os.path.dirname(os.path.abspath(__file__))
myzip = zipfile.ZipFile(os.path.join(thisdir, "quickfox.zip"))
docname = os.path.join(thisdir, "image-no-go.pdf") # "no go" input PDF file name
outname = os.path.join(thisdir, "quickfox-image-no-go.pdf") # output PDF file name
BORDER = 36 # global parameter
FONTSIZE = 12.5 # global parameter
COLS = 2 # number of text columns, global parameter
def analyze_page(page):
"""Compute MediaBox and rectangles on page that are free to receive text.
Notes:
Assume a BORDER around the page, make 2 columns of the resulting
sub-rectangle and extract the rectangles of all images on page.
For demo purposes, the image rectangles are taken as "NO-GO areas"
on the page when writing text with the Story.
The function returns free areas for each of the columns.
Returns:
(page.number, mediabox, CELLS), where CELLS is a list of free cells.
"""
prect = page.rect # page rectangle - will be our MEDIABOX later
where = prect + (BORDER, BORDER, -BORDER, -BORDER)
TABLE = pymupdf.make_table(where, rows=1, cols=COLS)
# extract rectangles covered by images on this page
IMG_RECTS = sorted( # image rects on page (sort top-left to bottom-right)
[pymupdf.Rect(item["bbox"]) for item in page.get_image_info()],
key=lambda b: (b.y1, b.x0),
)
def free_cells(column):
"""Return free areas in this column."""
free_stripes = [] # y-value pairs wrapping a free area stripe
# intersecting images: block complete intersecting column stripe
col_imgs = [(b.y0, b.y1) for b in IMG_RECTS if abs(b & column) > 0]
s_y0 = column.y0 # top y-value of column
for y0, y1 in col_imgs: # an image stripe
if y0 > s_y0 + FONTSIZE: # image starts below last free btm value
free_stripes.append((s_y0, y0)) # store as free stripe
s_y0 = y1 # start of next free stripe
if s_y0 + FONTSIZE < column.y1: # enough room to column bottom
free_stripes.append((s_y0, column.y1))
if free_stripes == []: # covers "no image in this column"
free_stripes.append((column.y0, column.y1))
# make available cells of this column
CELLS = [pymupdf.Rect(column.x0, y0, column.x1, y1) for (y0, y1) in free_stripes]
return CELLS
# collection of available Story rectangles on page
CELLS = []
for i in range(COLS):
CELLS.extend(free_cells(TABLE[0][i]))
return page.number, prect, CELLS
HTML = myzip.read("quickfox.html").decode()
# --------------------------------------------------------------
# Make the Story object
# --------------------------------------------------------------
story = pymupdf.Story(HTML)
# modify the DOM somewhat
body = story.body # access HTML body
body.set_properties(font="sans-serif") # and give it our font globally
# modify certain nodes
para = body.find("p", None, None) # find relevant nodes (here: paragraphs)
while para != None:
para.set_properties( # method MUST be used for existing nodes
indent=15,
fontsize=FONTSIZE,
)
para = para.find_next("p", None, None)
# we remove all image references, because the target PDF already has them
img = body.find("img", None, None)
while img != None:
next_img = img.find_next("img", None, None)
img.remove()
img = next_img
page_info = {} # contains MEDIABOX and free CELLS per page
doc = pymupdf.open(docname)
for page in doc:
pno, mediabox, cells = analyze_page(page)
page_info[pno] = (mediabox, cells)
doc.close() # close target PDF for now - re-open later
fileobject = io.BytesIO() # let DocumentWriter write to memory
writer = pymupdf.DocumentWriter(fileobject) # define output writer
more = 1 # stop if this ever becomes zero
pno = 0 # count output pages
while more: # loop until all HTML text has been written
try:
MEDIABOX, CELLS = page_info[pno]
except KeyError: # too much text space required: reduce fontsize?
raise ValueError("text does not fit on target PDF")
dev = writer.begin_page(MEDIABOX) # prepare a new output page
for cell in CELLS: # iterate over free cells on this page
if not more: # need to check this for every cell
continue
more, _ = story.place(cell)
story.draw(dev)
writer.end_page() # finish the PDF page
pno += 1
writer.close() # close DocumentWriter output
# Re-open writer output, read its pages and overlay target pages with them.
# The generated pages have same dimension as their targets.
src = pymupdf.open("pdf", fileobject)
doc = pymupdf.open(doc.name)
for page in doc: # overlay every target page with the prepared text
if page.number >= src.page_count:
print(f"Text only uses {src.page_count} target pages!")
continue # story did not need all target pages?
# overlay target page
page.show_pdf_page(page.rect, src, page.number)
# DEBUG start --- draw the text rectangles
# mb, cells = page_info[page.number]
# for cell in cells:
# page.draw_rect(cell, color=(1, 0, 0))
# DEBUG stop ---
doc.ez_save(outname)
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