a:blip (Blip/Image Reference)

Description

\:blip\ is the DrawingML element that references an image/picture for use in presentations, documents, and spreadsheets. It is defined in ECMA-376 Part 1 §20.1.2.2.1.

Blip elements provide:

• Embedded images: Store image data within package
• Linked images: Reference external image files
• Image effects: Apply filters (grayscale, duotone, tint, saturation)
• Alpha/transparency: Adjust image opacity
• Color modifications: Brighten, darken, recolor images
• Relationship management: Link to image relationships

Blip elements support:

• JPEG, PNG, GIF, BMP, TIFF, WMF, EMF image formats
• Embedded and linked image modes
• Multiple image effect filters
• Compression and optimization
• Color space specifications

Blip differs from:

• Blip fill (\:blipFill) — Shape fill using image (contains blip)
• Picture (\p:pic) — Picture shape in presentations
• Image source — Raw file (blip references it)

Attributes

Note: Either
:embed\ (embedded) OR
:link\ (linked), not both.

Content Model

\:blip\ children (all optional, 0–1):

1. Image effects (choose one or more):
   • \:alphaModFix\ — Fixed alpha modification
   • \:alphaMod\ — Alpha modulation with effect
   • \:alphaRepl\ — Alpha replacement
   • \:duotone\ — Duotone effect
   • \:grayscl\ — Grayscale effect
   • \:lumMod\ — Luminance modulation
   • \:lumOff\ — Luminance offset
   • \:tint\ — Color tint
   • \:shade\ — Color shade
   • \:sat\ — Saturation
   • \:satMod\ — Saturation modulation
   • \:hue\ — Hue shift
   • \:cSpc\ — Color space
2. a:ext (0–1) — Extended properties (future)

Examples

Simple Embedded Image

<a:blipFill>
  <a:blip r:embed="rId4" cstate="print">
    <a:alphaModFix amt="100000"/>
  </a:blip>
  <a:stretch>
    <a:fillRect/>
  </a:stretch>
</a:blipFill>

using DocumentFormat.OpenXml.Drawing;
using DocumentFormat.OpenXml.Packaging;

var blipFill = new BlipFill();

var blip = new Blip { Embed = "rId4", CompressionState = "print" };
var alphaModFix = new AlphaModulationFixed { Amount = 100000 };
blip.Append(alphaModFix);
blipFill.Append(blip);

var stretch = new Stretch();
stretch.Append(new FillRectangle());
blipFill.Append(stretch);

Linked External Image

<a:blipFill>
  <a:blip r:link="https://example.com/image.jpg" cstate="screen"/>
  <a:stretch>
    <a:fillRect/>
  </a:stretch>
</a:blipFill>

var blipFill = new BlipFill();

var blip = new Blip 
{ 
  Link = "https://example.com/image.jpg", 
  CompressionState = "screen" 
};
blipFill.Append(blip);

var stretch = new Stretch();
stretch.Append(new FillRectangle());
blipFill.Append(stretch);

Image with Grayscale Effect

<a:blip r:embed="rId4">
  <a:grayscl/>
</a:blip>

var blip = new Blip { Embed = "rId4" };
var grayscl = new Grayscale();
blip.Append(grayscl);

Image with Duotone Effect

<a:blip r:embed="rId4">
  <a:duotone>
    <a:srgbClr val="0070C0"/>
    <a:srgbClr val="FFD700"/>
  </a:duotone>
</a:blip>

var blip = new Blip { Embed = "rId4" };

var duotone = new Duotone();
var color1 = new RgbColorModelHex { Val = "0070C0" };
var color2 = new RgbColorModelHex { Val = "FFD700" };
duotone.Append(color1);
duotone.Append(color2);
blip.Append(duotone);

Image with Tint and Transparency

<a:blip r:embed="rId4">
  <a:alphaMod>
    <a:alphaModFix amt="75000"/>
  </a:alphaMod>
  <a:tint val="CCE5FF"/>
</a:blip>

var blip = new Blip { Embed = "rId4" };

var alphaMod = new AlphaModulation();
var alphaModFix = new AlphaModulationFixed { Amount = 75000 };
alphaMod.Append(alphaModFix);
blip.Append(alphaMod);

var tint = new Tint { Val = "CCE5FF" };
blip.Append(tint);

Image with Saturation Adjustment

<a:blip r:embed="rId4">
  <a:satMod val="150000"/>
</a:blip>

var blip = new Blip { Embed = "rId4" };
var satMod = new SaturationModulation { Val = 150000 };
blip.Append(satMod);

Image Format Support

Compression States

Image Effects Reference

Transparency Effects

Color Effects

Composite Effects

Multiple effects can be applied (processed in order):

xml <a:blip r:embed="rId4"> <a:grayscl/> <a:satMod val="80000"/> <a:lumMod val="120000"/> </a:blip>

Processed: Grayscale → Reduce saturation → Increase luminance

Relationship Management

Embedded Images

Relationship file (document.xml.rels or similar):

`xml