PROBLEM DESCRIPTION

Images are not scaled correctly in JEditorPane
When JEditorPane is used to display HTML content, referenced images are
displayed distorted if only width is specified for the image.
To reproduce the issue, store attached 'circle.png' file somewhere on
file
system, specify path to it in attached ImageTest.java file, compile and
run
it. Expected result - black filled circle is displayed in opened window
(of
approximately 200px diameter). Actual result - black filled ellipse is
displayed (of approximately 200px width and 40px height).
The issue can be reproduced with latest Java 8 (1.8.0_152) and 9 (9.0.1)
builds on Windows 10. I believe, the issue is platform-independent. I'm
not
aware of any previous Java version where this worked correctly.

END PROBLEM DESCRIPTION

Source Code

------------------------------------
ImageTest.java
============
import javax.swing.*;

public class ImageTest {
 private static final String ABSOLUTE_FILE_PATH =
"c:\\ws\\Test\\src\\test\\circle.png";
 
 public static void main(String[] args) {
 SwingUtilities.invokeLater(() -> {
 JFrame f = new JFrame();
 // the following line is expected to work in the same
 //way
 //as the next (commented) line, as the image has aspect ratio 1:1
 JEditorPane editorPane = new JEditorPane("text/html",
"<img width=\"200\" src=\"file:///" + ABSOLUTE_FILE_PATH + "\">");
 // JEditorPane editorPane = new JEditorPane("text/html",
//"<img width=\"200\" height=\"200\" src=\"file:///" + ABSOLUTE_FILE_PATH +
//"\">");
 editorPane.setEditable(false);
 f.add(editorPane);
 f.setSize(220, 240);
 f.setLocationRelativeTo(null);

 f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
 f.setVisible(true);
 });
}
}

End Source

Expected result - black filled circle is displayed in opened window (of
approximately 200px diameter). Actual result - black filled ellipse is
displayed (of approximately 200px width and 40px height).
Workaround
----------
None