Recipes: Annotations

In v1.14.0, annotation handling has been considerably extended:

  • New annotation type support for ‘Ink’, ‘Rubber Stamp’ and ‘Squiggly’ annotations. Ink annots simulate handwriting by combining one or more lists of interconnected points. Stamps are intended to visually inform about a document’s status or intended usage (like “draft”, “confidential”, etc.). ‘Squiggly’ is a text marker annot, which underlines selected text with a zig-zagged line.

  • Extended ‘FreeText’ support:
    1. all characters from the Latin character set are now available,

    2. colors of text, rectangle background and rectangle border can be independently set

    3. text in rectangle can be rotated by either +90 or -90 degrees

    4. text is automatically wrapped (made multi-line) in available rectangle

    5. all Base-14 fonts are now available (normal variants only, i.e. no bold, no italic).

  • MuPDF now supports line end icons for ‘Line’ annots (only). PyMuPDF supported that in v1.13.x already – and for (almost) the full range of applicable types. So we adjusted the appearance of ‘Polygon’ and ‘PolyLine’ annots to closely resemble the one of MuPDF for ‘Line’.

  • MuPDF now provides its own annotation icons where relevant. PyMuPDF switched to using them (for ‘FileAttachment’ and ‘Text’ [“sticky note”] so far).

  • MuPDF now also supports ‘Caret’, ‘Movie’, ‘Sound’ and ‘Signature’ annotations, which we may include in PyMuPDF at some later time.

How to Add and Modify Annotations

In PyMuPDF, new annotations can be added via Page methods. Once an annotation exists, it can be modified to a large extent using methods of the Annot class.

In contrast to many other tools, initial insert of annotations happens with a minimum number of properties. We leave it to the programmer to e.g. set attributes like author, creation date or subject.

As an overview for these capabilities, look at the following script that fills a PDF page with most of the available annotations. Look in the next sections for more special situations:

# -*- coding: utf-8 -*-
"""
-------------------------------------------------------------------------------
Demo script showing how annotations can be added to a PDF using PyMuPDF.

It contains the following annotation types:
Caret, Text, FreeText, text markers (underline, strike-out, highlight,
squiggle), Circle, Square, Line, PolyLine, Polygon, FileAttachment, Stamp
and Redaction.
There is some effort to vary appearances by adding colors, line ends,
opacity, rotation, dashed lines, etc.

Dependencies
------------
PyMuPDF v1.17.0
-------------------------------------------------------------------------------
"""
from __future__ import print_function

import gc
import sys

import fitz

print(fitz.__doc__)
if fitz.VersionBind.split(".") < ["1", "17", "0"]:
    sys.exit("PyMuPDF v1.17.0+ is needed.")

gc.set_debug(gc.DEBUG_UNCOLLECTABLE)

highlight = "this text is highlighted"
underline = "this text is underlined"
strikeout = "this text is striked out"
squiggled = "this text is zigzag-underlined"
red = (1, 0, 0)
blue = (0, 0, 1)
gold = (1, 1, 0)
green = (0, 1, 0)

displ = fitz.Rect(0, 50, 0, 50)
r = fitz.Rect(72, 72, 220, 100)
t1 = u"têxt üsès Lätiñ charß,\nEUR: €, mu: µ, super scripts: ²³!"


def print_descr(annot):
    """Print a short description to the right of each annot rect."""
    annot.parent.insert_text(
        annot.rect.br + (10, -5), "%s annotation" % annot.type[1], color=red
    )


doc = fitz.open()
page = doc.new_page()

page.set_rotation(0)

annot = page.add_caret_annot(r.tl)
print_descr(annot)

r = r + displ
annot = page.add_freetext_annot(
    r,
    t1,
    fontsize=10,
    rotate=90,
    text_color=blue,
    fill_color=gold,
    align=fitz.TEXT_ALIGN_CENTER,
)
annot.set_border(width=0.3, dashes=[2])
annot.update(text_color=blue, fill_color=gold)
print_descr(annot)

r = annot.rect + displ
annot = page.add_text_annot(r.tl, t1)
print_descr(annot)

# Adding text marker annotations:
# first insert a unique text, then search for it, then mark it
pos = annot.rect.tl + displ.tl
page.insert_text(
    pos,  # insertion point
    highlight,  # inserted text
    morph=(pos, fitz.Matrix(-5)),  # rotate around insertion point
)
rl = page.search_for(highlight, quads=True)  # need a quad b/o tilted text
annot = page.add_highlight_annot(rl[0])
print_descr(annot)

pos = annot.rect.bl  # next insertion point
page.insert_text(pos, underline, morph=(pos, fitz.Matrix(-10)))
rl = page.search_for(underline, quads=True)
annot = page.add_underline_annot(rl[0])
print_descr(annot)

pos = annot.rect.bl
page.insert_text(pos, strikeout, morph=(pos, fitz.Matrix(-15)))
rl = page.search_for(strikeout, quads=True)
annot = page.add_strikeout_annot(rl[0])
print_descr(annot)

pos = annot.rect.bl
page.insert_text(pos, squiggled, morph=(pos, fitz.Matrix(-20)))
rl = page.search_for(squiggled, quads=True)
annot = page.add_squiggly_annot(rl[0])
print_descr(annot)

pos = annot.rect.bl
r = fitz.Rect(pos, pos.x + 75, pos.y + 35) + (0, 20, 0, 20)
annot = page.add_polyline_annot([r.bl, r.tr, r.br, r.tl])  # 'Polyline'
annot.set_border(width=0.3, dashes=[2])
annot.set_colors(stroke=blue, fill=green)
annot.set_line_ends(fitz.PDF_ANNOT_LE_CLOSED_ARROW, fitz.PDF_ANNOT_LE_R_CLOSED_ARROW)
annot.update(fill_color=(1, 1, 0))
print_descr(annot)

r += displ
annot = page.add_polygon_annot([r.bl, r.tr, r.br, r.tl])  # 'Polygon'
annot.set_border(width=0.3, dashes=[2])
annot.set_colors(stroke=blue, fill=gold)
annot.set_line_ends(fitz.PDF_ANNOT_LE_DIAMOND, fitz.PDF_ANNOT_LE_CIRCLE)
annot.update()
print_descr(annot)

r += displ
annot = page.add_line_annot(r.tr, r.bl)  # 'Line'
annot.set_border(width=0.3, dashes=[2])
annot.set_colors(stroke=blue, fill=gold)
annot.set_line_ends(fitz.PDF_ANNOT_LE_DIAMOND, fitz.PDF_ANNOT_LE_CIRCLE)
annot.update()
print_descr(annot)

r += displ
annot = page.add_rect_annot(r)  # 'Square'
annot.set_border(width=1, dashes=[1, 2])
annot.set_colors(stroke=blue, fill=gold)
annot.update(opacity=0.5)
print_descr(annot)

r += displ
annot = page.add_circle_annot(r)  # 'Circle'
annot.set_border(width=0.3, dashes=[2])
annot.set_colors(stroke=blue, fill=gold)
annot.update()
print_descr(annot)

r += displ
annot = page.add_file_annot(
    r.tl, b"just anything for testing", "testdata.txt"  # 'FileAttachment'
)
print_descr(annot)  # annot.rect

r += displ
annot = page.add_stamp_annot(r, stamp=10)  # 'Stamp'
annot.set_colors(stroke=green)
annot.update()
print_descr(annot)

r += displ + (0, 0, 50, 10)
rc = page.insert_textbox(
    r,
    "This content will be removed upon applying the redaction.",
    color=blue,
    align=fitz.TEXT_ALIGN_CENTER,
)
annot = page.add_redact_annot(r)
print_descr(annot)

doc.save(__file__.replace(".py", "-%i.pdf" % page.rotation), deflate=True)

This script should lead to the following output:

_images/img-annots.jpg

How to Use FreeText

This script shows a couple of ways to deal with ‘FreeText’ annotations:

# -*- coding: utf-8 -*-
import fitz

# some colors
blue  = (0,0,1)
green = (0,1,0)
red   = (1,0,0)
gold  = (1,1,0)

# a new PDF with 1 page
doc = fitz.open()
page = doc.new_page()

# 3 rectangles, same size, above each other
r1 = fitz.Rect(100,100,200,150)
r2 = r1 + (0,75,0,75)
r3 = r2 + (0,75,0,75)

# the text, Latin alphabet
t = "¡Un pequeño texto para practicar!"

# add 3 annots, modify the last one somewhat
a1 = page.add_freetext_annot(r1, t, color=red)
a2 = page.add_freetext_annot(r2, t, fontname="Ti", color=blue)
a3 = page.add_freetext_annot(r3, t, fontname="Co", color=blue, rotate=90)
a3.set_border(width=0)
a3.update(fontsize=8, fill_color=gold)

# save the PDF
doc.save("a-freetext.pdf")

The result looks like this:

_images/img-freetext.jpg

Using Buttons and JavaScript

Since MuPDF v1.16, ‘FreeText’ annotations no longer support bold or italic versions of the Times-Roman, Helvetica or Courier fonts.

A big thank you to our user @kurokawaikki, who contributed the following script to circumvent this restriction.

"""
Problem: Since MuPDF v1.16 a 'Freetext' annotation font is restricted to the
"normal" versions (no bold, no italics) of Times-Roman, Helvetica, Courier.
It is impossible to use PyMuPDF to modify this.

Solution: Using Adobe's JavaScript API, it is possible to manipulate properties
of Freetext annotations. Check out these references:
https://www.adobe.com/content/dam/acom/en/devnet/acrobat/pdfs/js_api_reference.pdf,
or https://www.adobe.com/devnet/acrobat/documentation.html.

Function 'this.getAnnots()'  will return all annotations  as an array. We loop
over this array to set the properties of the text through the 'richContents'
attribute.
There is no explicit property to set text to bold, but it is possible to set
fontWeight=800 (400 is the normal size) of richContents.
Other attributes, like color, italics, etc. can also be set via richContents.

If we have 'FreeText' annotations created with PyMuPDF, we can make use of this
JavaScript feature to modify the font - thus circumventing the above restriction.

Use PyMuPDF v1.16.12 to create a push button that executes a Javascript
containing the desired code. This is what this program does.
Then open the resulting file with Adobe reader (!).
After clicking on the button, all Freetext annotations will be bold, and the
file can be saved.
If desired, the button can be removed again, using free tools like PyMuPDF or
PDF XChange editor.

Note / Caution:
---------------
The JavaScript will **only** work if the file is opened with Adobe Acrobat reader!
When using other PDF viewers, the reaction is unforeseeable.
"""
import sys

import fitz

# this JavaScript will execute when the button is clicked:
jscript = """
var annt = this.getAnnots();
annt.forEach(function (item, index) {
    try {
        var span = item.richContents;
        span.forEach(function (it, dx) {
            it.fontWeight = 800;
        })
        item.richContents = span;
    } catch (err) {}
});
app.alert('Done');
"""
i_fn = sys.argv[1]  # input file name
o_fn = "bold-" + i_fn  # output filename
doc = fitz.open(i_fn)  # open input
page = doc[0]  # get desired page

# ------------------------------------------------
# make a push button for invoking the JavaScript
# ------------------------------------------------

widget = fitz.Widget()  # create widget

# make it a 'PushButton'
widget.field_type = fitz.PDF_WIDGET_TYPE_BUTTON
widget.field_flags = fitz.PDF_BTN_FIELD_IS_PUSHBUTTON

widget.rect = fitz.Rect(5, 5, 20, 20)  # button position

widget.script = jscript  # fill in JavaScript source text
widget.field_name = "Make bold"  # arbitrary name
widget.field_value = "Off"  # arbitrary value
widget.fill_color = (0, 0, 1)  # make button visible

annot = page.add_widget(widget)  # add the widget to the page
doc.save(o_fn)  # output the file

How to Use Ink Annotations

Ink annotations are used to contain freehand scribbling. A typical example may be an image of your signature consisting of first name and last name. Technically an ink annotation is implemented as a list of lists of points. Each point list is regarded as a continuous line connecting the points. Different point lists represent independent line segments of the annotation.

The following script creates an ink annotation with two mathematical curves (sine and cosine function graphs) as line segments:

import math
import fitz

#------------------------------------------------------------------------------
# preliminary stuff: create function value lists for sine and cosine
#------------------------------------------------------------------------------
w360 = math.pi * 2  # go through full circle
deg = w360 / 360  # 1 degree as radians
rect = fitz.Rect(100,200, 300, 300)  # use this rectangle
first_x = rect.x0  # x starts from left
first_y = rect.y0 + rect.height / 2.  # rect middle means y = 0
x_step = rect.width / 360  # rect width means 360 degrees
y_scale = rect.height / 2.  # rect height means 2
sin_points = []  # sine values go here
cos_points = []  # cosine values go here
for x in range(362):  # now fill in the values
    x_coord = x * x_step + first_x  # current x coordinate
    y = -math.sin(x * deg)  # sine
    p = (x_coord, y * y_scale + first_y)  # corresponding point
    sin_points.append(p)  # append
    y = -math.cos(x * deg)  # cosine
    p = (x_coord, y * y_scale + first_y)  # corresponding point
    cos_points.append(p)  # append

#------------------------------------------------------------------------------
# create the document with one page
#------------------------------------------------------------------------------
doc = fitz.open()  # make new PDF
page = doc.new_page()  # give it a page

#------------------------------------------------------------------------------
# add the Ink annotation, consisting of 2 curve segments
#------------------------------------------------------------------------------
annot = page.addInkAnnot((sin_points, cos_points))
# let it look a little nicer
annot.set_border(width=0.3, dashes=[1,])  # line thickness, some dashing
annot.set_colors(stroke=(0,0,1))  # make the lines blue
annot.update()  # update the appearance

page.draw_rect(rect, width=0.3)  # only to demonstrate we did OK

doc.save("a-inktest.pdf")

This is the result:

_images/img-inkannot.jpg