public void toString(final PrintWriter pw, final String prefix) {
        pw.println("Format Details: " + formatDetails);

        pw.println("Bits Per Pixel: " + bitsPerPixel);
        pw.println("Comments: " + comments.size());
        for (int i = 0; i < comments.size(); i++) {
            final String s = comments.get(i);
            pw.println("\t" + i + ": '" + s + "'");

        }
        pw.println("Format: " + format.getName());
        pw.println("Format Name: " + formatName);
        pw.println("Compression Algorithm: " + compressionAlgorithm);
        pw.println("Height: " + height);
        pw.println("MimeType: " + mimeType);
        pw.println("Number Of Images: " + numberOfImages);
        pw.println("Physical Height Dpi: " + physicalHeightDpi);
        pw.println("Physical Height Inch: " + physicalHeightInch);
        pw.println("Physical Width Dpi: " + physicalWidthDpi);
        pw.println("Physical Width Inch: " + physicalWidthInch);
        pw.println("Width: " + width);
        pw.println("Is Progressive: " + progressive);
        pw.println("Is Transparent: " + transparent);

        pw.println("Color Type: " + colorType.toString());
        pw.println("Uses Palette: " + usesPalette);

        pw.flush();

    }
Returns true if the image has transparency.

@return {@code true} if the image has transparency, {@code false} otherwise.
src/main/java/org/apache/commons/imaging/ImageInfo.java