---
title: "Add an image to a PDF in C#"
url: https://recursiveai.org/onepdf/cookbook/add-image-to-pdf/
description: "Add a PNG or JPEG image to an existing PDF in C# at an exact position and size, keeping transparency. Runnable code, with OnePDF."
version: "1.15.0"
---

# Add an image to a PDF in C#

Add the image to the document with `AddPngImage` or `AddJpegImage`, then draw it on a page with `DrawImage` at a position and size in points. The program below puts a logo in the top right corner of the IRS Form W-9, a public PDF you can download to try it.

```shell
dotnet new console -o AddImage && cd AddImage
dotnet add package RecursiveAI.OnePdf --version 1.15.0
curl -LO https://www.irs.gov/pub/irs-pdf/fw9.pdf
curl -o logo.png https://recursiveai.org/assets/brand/icon-512.png
```

Put this in `Program.cs` and run `dotnet run`:

```csharp
using OnePdf;

using PdfDocument doc = PdfDocument.Open("fw9.pdf",
    new PdfOpenOptions { AllowEditing = true });

// Add the image once; it can then be drawn on any number of pages.
// or AddJpegImage
PdfCreatedImage logo = doc.AddPngImage(File.ReadAllBytes("logo.png"));

PdfPage page = doc.Pages[0];
PdfRectangle size = page.MediaBox;
Console.WriteLine($"Page 1 is {size.Width:0} x {size.Height:0} points");
Console.WriteLine($"logo.png is {logo.Width} x {logo.Height} pixels");

// 24 points wide (1/3 inch), height from the image's aspect ratio.
double width = 24, height = width * logo.Height / logo.Width;

using (PdfPageContentBuilder b = page.BeginContent())   // over the existing content
{
    b.DrawImage(logo, 552, 764, width, height);   // x, y of its lower left corner
    b.Commit();                                 // nothing is written before Commit
}

doc.Save("fw9-logo.pdf");
Console.WriteLine("Saved fw9-logo.pdf");
```

```text
Page 1 is 612 x 792 points
logo.png is 512 x 512 pixels
Saved fw9-logo.pdf
```

The logo now sits in the top right corner of page 1, a third of an inch square, in the margin above the form, with its transparent background kept. The page’s own content is unchanged.

## Positions and sizes

- Coordinates are in points, 72 to the inch, from the lower left corner of the page, with y going up. A US Letter page is 612 × 792 points and A4 is 595 × 842. `page.MediaBox` gives the size of any page.
- `DrawImage` stretches the image to the box you give it, so compute one side from the other to keep the aspect ratio, as above.
- An image prints at its pixel width divided by the box width in inches: 512 pixels across 1/3 inch is 1,536 dpi, far more than print needs, so scale large images down before adding them to keep the file small.
- `page.BeginContent(PdfContentPlacement.Underlay)` draws under the page’s content instead of over it.
- To put the same image on every page, call `DrawImage` in a loop over `doc.Pages`. The image is stored once.

## Limits

- **JPEG and PNG only.** `AddJpegImage` embeds a JPEG’s bytes as they are, without recompressing (baseline and progressive; arithmetic-coded and lossless JPEGs are refused). `AddPngImage` stores a PNG losslessly, its alpha channel as a soft mask. Convert other formats first, or pass raw pixels to `AddRawImage`.
- **Rotated pages.** Content you draw isn’t turned with a page that has `/Rotate` set, so the image appears rotated. Check `page.Rotate`, or use a [stamp](https://recursiveai.org/onepdf/cookbook/add-watermark/), which compensates.
- **Signed PDFs.** Adding an image changes the page, so do it before signing.

For a logo or text on every page, faint and rotated, see [Add a watermark to a PDF](https://recursiveai.org/onepdf/cookbook/add-watermark/). To pull images out of a PDF, see [Extract images from a PDF](https://recursiveai.org/onepdf/cookbook/extract-images/). Text, lines and shapes are drawn with the same builder: see [Content creation](https://recursiveai.org/onepdf/docs/content-creation/).