com.aspose.words

Example:

Document doc = new Document(getMyDir() + "Embedded font.docx");

FontInfo embeddedFont = doc.getFontInfos().get("Alte DIN 1451 Mittelschrift");
byte[] embeddedFontBytes = embeddedFont.getEmbeddedFont(EmbeddedFontFormat.OPEN_TYPE, EmbeddedFontStyle.REGULAR);

FileUtils.writeByteArrayToFile(new File(getArtifactsDir() + "Alte DIN 1451 Mittelschrift.ttf"), embeddedFontBytes);

// Embedded font formats may be different in other formats such as .doc.
// We need to know the correct format before we can extract the font.
doc = new Document(getMyDir() + "Embedded font.doc");

Assert.assertNull(doc.getFontInfos().get("Alte DIN 1451 Mittelschrift").getEmbeddedFont(EmbeddedFontFormat.OPEN_TYPE, EmbeddedFontStyle.REGULAR));
Assert.assertNotNull(doc.getFontInfos().get("Alte DIN 1451 Mittelschrift").getEmbeddedFont(EmbeddedFontFormat.EMBEDDED_OPEN_TYPE, EmbeddedFontStyle.REGULAR));

// Also, we can convert embedded OpenType format, which comes from .doc documents, to OpenType.
embeddedFontBytes = doc.getFontInfos().get("Alte DIN 1451 Mittelschrift").getEmbeddedFontAsOpenType(EmbeddedFontStyle.REGULAR);

FileUtils.writeByteArrayToFile(new File(getArtifactsDir() + "Alte DIN 1451 Mittelschrift.otf"), embeddedFontBytes);