Bug 104986 Backgound image uses an absolute path
Currently Chart uses an absolute path to indicate a backgournd image, that may cause the design unusable on other environments. Expected the background image can be definded in multiple ways like in report designer. e.g. URI(absolute path), File(relative path), Embedded Image(Encoded Image Data).
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/model/attribute/AttributePackage.java
EAttribute getMarker_Size( );
	/**
	 * Returns the meta object for the attribute '{@link org.eclipse.birt.chart.model.attribute.Marker#isVisible <em>Visible</em>}'.
	 * <!-- begin-user-doc --> <!-- end-user-doc -->
	 * @return the meta object for the attribute '<em>Visible</em>'.
	 * @see org.eclipse.birt.chart.model.attribute.Marker#isVisible()
	 * @see #getMarker()
	 * @generated
	 */
	EAttribute getMarker_Visible( );
	/**
	 * Returns the meta object for the containment reference '{@link org.eclipse.birt.chart.model.attribute.Marker#getIconPalette <em>Icon Palette</em>}'.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @return the meta object for the containment reference '<em>Icon Palette</em>'.
	 * @see org.eclipse.birt.chart.model.attribute.Marker#getIconPalette()
	 * @see #getMarker()
	 * @generated
	 */
	EReference getMarker_IconPalette( );
	/**
	 * Returns the meta object for class '{@link org.eclipse.birt.chart.model.attribute.NumberFormatSpecifier <em>Number Format Specifier</em>}'.
	 * <!-- begin-user-doc --> <!-- end-user-doc -->
	 * @return the meta object for class '<em>Number Format Specifier</em>'.
	 * @see org.eclipse.birt.chart.model.attribute.NumberFormatSpecifier
	 * @generated
	 */
	EClass getNumberFormatSpecifier( );
	/**
	 * Returns the meta object for the attribute '{@link org.eclipse.birt.chart.model.attribute.NumberFormatSpecifier#getPrefix <em>Prefix</em>}'.