# Adding PDF Annotations

```{note}
By default, some annotations might be invisible, for example polylines, as the default color is "transparent".

To circumvent this, make sure to add the `/C` entry to the annotation, being an array and each array value being in the range 0.0 to 1.0:

  * With one element, a grayscale value.
  * With three elements, a RGB definition.
  * With four elements, a CMYK definition.
```

## Attachments

```{testsetup}
pypdf_test_setup("user/adding-pdf-annotations", {
    "crazyones.pdf": "../resources/crazyones.pdf",
})
```

```{testcode}
from pypdf import PdfWriter

writer = PdfWriter()
writer.add_blank_page(width=200, height=200)

data = b"any bytes - typically read from a file"
writer.add_attachment("smile.png", data)

writer.write("out-attachment.pdf")
```


## Free Text

If you want to add text in a box like this

![](free-text-annotation.png)

you can use {class}`~pypdf.annotations.FreeText`:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import FreeText

# Fill the writer with the pages you want
reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

# Create the annotation and add it
annotation = FreeText(
    text="Hello World\nThis is the second line!",
    rect=(50, 550, 200, 650),
    font="Arial",
    bold=True,
    italic=True,
    font_size="20pt",
    font_color="00ff00",
    border_color="0000ff",
    background_color="cdcdcd",
)

# Set annotation flags to 4 for printable annotations.
# See "AnnotationFlag" for other options, e.g. hidden etc.
annotation.flags = 4

writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-free-text.pdf")
```

## Text

A text annotation looks like this:

![](text-annotation.png)

## Line

If you want to add a line like this:

![](annotation-line.png)

you can use {class}`~pypdf.annotations.Line`:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import Line

reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

# Add the line
annotation = Line(
    text="Hello World\nLine2",
    rect=(50, 550, 200, 650),
    p1=(50, 550),
    p2=(200, 650),
)
writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-line.pdf")
```

## PolyLine

If you want to add a line like this:

![](annotation-polyline.png)

you can use {class}`~pypdf.annotations.PolyLine`:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import PolyLine
from pypdf.generic import ArrayObject, FloatObject, NameObject

reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

# Add the polyline
# By default, the line will be transparent. Set an explicit color.
annotation = PolyLine(
    vertices=[(50, 550), (200, 650), (70, 750), (50, 700)],
)
annotation[NameObject("/C")] = ArrayObject(
    [FloatObject(0.9), FloatObject(0.1), FloatObject(0)]
)
writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-polyline.pdf")
```

## Rectangle

If you want to add a rectangle like this:

![](annotation-square.png)

you can use {class}`~pypdf.annotations.Rectangle`:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import Rectangle

reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

# Add the rectangle
annotation = Rectangle(
    rect=(50, 550, 200, 650),
)
writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-rectangle.pdf")
```

If you want the rectangle to be filled, use the `interiour_color="ff0000"` parameter.

This method uses the "square" annotation type of the PDF format.


## Ellipse

If you want to add a circle like this:

![](annotation-circle.png)

you can use {class}`~pypdf.annotations.Ellipse`:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import Ellipse

reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

# Add the rectangle
annotation = Ellipse(
    rect=(50, 550, 200, 650),
)
writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-ellipse.pdf")
```

## Polygon

If you want to add a polygon like this:

![](annotation-polygon.png)

you can use {class}`~pypdf.annotations.Polygon`:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import Polygon

reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

# Add the line
annotation = Polygon(
    vertices=[(50, 550), (200, 650), (70, 750), (50, 700)],
)
writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-polygon.pdf")
```

## Popup

Manage the Popup windows for markups, looks like this:

![](annotation-popup.png)

you can use {py:class}`~pypdf.annotations.Popup`:

```{testcode}
from pypdf import PdfWriter
from pypdf.annotations import Popup, Text

# Arrange
writer = PdfWriter()
writer.append("crazyones.pdf", [0])

# Act
text_annotation = writer.add_annotation(
    0,
    Text(
        text="Hello World\nThis is the second line!",
        rect=(50, 550, 200, 650),
        open=True,
    ),
)

popup_annotation = Popup(
    rect=(50, 550, 200, 650),
    open=True,
    parent=text_annotation,  # use the output of add_annotation
)

writer.write("out-popup.pdf")
```

You have to use the returned result from add_annotation() as it is
the parent annotation with which this popup annotation shall be associated.

## Link

If you want to add a link, you can use {class}`~pypdf.annotations.Link`:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import Link

reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

# Add the link
annotation = Link(
    rect=(50, 550, 200, 650),
    url="https://martin-thoma.com/",
)
writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-link.pdf")
```

You can also add internal links:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import Link
from pypdf.generic import Fit

reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

# Add the link
annotation = Link(
    rect=(50, 550, 200, 650),
    target_page_index=3,
    fit=Fit(fit_type="/FitH", fit_args=(123,)),
)
writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-internal-link.pdf")
```

## Text Markup Annotations

Text markup annotations refer to a specific piece of text within the document.

These are a bit more complicated as you need to know exactly where the text
is, the so-called "Quad points".

### Highlighting

If you want to highlight text like this:

![](annotation-highlight.png)

you can use {class}`~pypdf.annotations.Highlight`:

```{testcode}
from pypdf import PdfReader, PdfWriter
from pypdf.annotations import Highlight
from pypdf.generic import ArrayObject, FloatObject

reader = PdfReader("crazyones.pdf")
page = reader.pages[0]
writer = PdfWriter()
writer.add_page(page)

rect = (50, 550, 200, 650)
quad_points = [rect[0], rect[1], rect[2], rect[1], rect[0], rect[3], rect[2], rect[3]]

# Add the highlight
annotation = Highlight(
    rect=rect,
    quad_points=ArrayObject([FloatObject(quad_point) for quad_point in quad_points]),
)
writer.add_annotation(page_number=0, annotation=annotation)

# Write the annotated file to disk
writer.write("out-highlight.pdf")
```
