--- /dev/null
+package be.nikiroo.utils;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+
+import be.nikiroo.utils.serial.SerialUtils;
+
+/**
+ * This class offer some utilities based around images.
+ *
+ * @author niki
+ */
+public abstract class ImageUtils {
+ private static ImageUtils instance = newObject();
+
+ /**
+ * Get a (unique) instance of an {@link ImageUtils} compatible with your
+ * system.
+ *
+ * @return an {@link ImageUtils}
+ */
+ public static ImageUtils getInstance() {
+ return instance;
+ }
+
+ /**
+ * Save the given resource as an image on disk using the given image format
+ * for content, or with "png" format if it fails.
+ *
+ * @param img
+ * the resource
+ * @param target
+ * the target file
+ * @param format
+ * the file format ("png", "jpeg", "bmp"...)
+ *
+ * @throws IOException
+ * in case of I/O error
+ */
+ public abstract void saveAsImage(Image img, File target, String format)
+ throws IOException;
+
+ /**
+ * Return the EXIF transformation flag of this image if any.
+ *
+ * <p>
+ * Note: this code has been found on internet; thank you anonymous coder.
+ * </p>
+ *
+ * @param in
+ * the data {@link InputStream}
+ *
+ * @return the transformation flag if any
+ *
+ * @throws IOException
+ * in case of IO error
+ */
+ protected static int getExifTransorm(InputStream in) throws IOException {
+ int[] exif_data = new int[100];
+ int set_flag = 0;
+ int is_motorola = 0;
+
+ /* Read File head, check for JPEG SOI + Exif APP1 */
+ for (int i = 0; i < 4; i++)
+ exif_data[i] = in.read();
+
+ if (exif_data[0] != 0xFF || exif_data[1] != 0xD8
+ || exif_data[2] != 0xFF || exif_data[3] != 0xE1)
+ return -2;
+
+ /* Get the marker parameter length count */
+ int length = (in.read() << 8 | in.read());
+
+ /* Length includes itself, so must be at least 2 */
+ /* Following Exif data length must be at least 6 */
+ if (length < 8)
+ return -1;
+ length -= 8;
+ /* Read Exif head, check for "Exif" */
+ for (int i = 0; i < 6; i++)
+ exif_data[i] = in.read();
+
+ if (exif_data[0] != 0x45 || exif_data[1] != 0x78
+ || exif_data[2] != 0x69 || exif_data[3] != 0x66
+ || exif_data[4] != 0 || exif_data[5] != 0)
+ return -1;
+
+ /* Read Exif body */
+ length = length > exif_data.length ? exif_data.length : length;
+ for (int i = 0; i < length; i++)
+ exif_data[i] = in.read();
+
+ if (length < 12)
+ return -1; /* Length of an IFD entry */
+
+ /* Discover byte order */
+ if (exif_data[0] == 0x49 && exif_data[1] == 0x49)
+ is_motorola = 0;
+ else if (exif_data[0] == 0x4D && exif_data[1] == 0x4D)
+ is_motorola = 1;
+ else
+ return -1;
+
+ /* Check Tag Mark */
+ if (is_motorola == 1) {
+ if (exif_data[2] != 0)
+ return -1;
+ if (exif_data[3] != 0x2A)
+ return -1;
+ } else {
+ if (exif_data[3] != 0)
+ return -1;
+ if (exif_data[2] != 0x2A)
+ return -1;
+ }
+
+ /* Get first IFD offset (offset to IFD0) */
+ int offset;
+ if (is_motorola == 1) {
+ if (exif_data[4] != 0)
+ return -1;
+ if (exif_data[5] != 0)
+ return -1;
+ offset = exif_data[6];
+ offset <<= 8;
+ offset += exif_data[7];
+ } else {
+ if (exif_data[7] != 0)
+ return -1;
+ if (exif_data[6] != 0)
+ return -1;
+ offset = exif_data[5];
+ offset <<= 8;
+ offset += exif_data[4];
+ }
+ if (offset > length - 2)
+ return -1; /* check end of data segment */
+
+ /* Get the number of directory entries contained in this IFD */
+ int number_of_tags;
+ if (is_motorola == 1) {
+ number_of_tags = exif_data[offset];
+ number_of_tags <<= 8;
+ number_of_tags += exif_data[offset + 1];
+ } else {
+ number_of_tags = exif_data[offset + 1];
+ number_of_tags <<= 8;
+ number_of_tags += exif_data[offset];
+ }
+ if (number_of_tags == 0)
+ return -1;
+ offset += 2;
+
+ /* Search for Orientation Tag in IFD0 */
+ for (;;) {
+ if (offset > length - 12)
+ return -1; /* check end of data segment */
+ /* Get Tag number */
+ int tagnum;
+ if (is_motorola == 1) {
+ tagnum = exif_data[offset];
+ tagnum <<= 8;
+ tagnum += exif_data[offset + 1];
+ } else {
+ tagnum = exif_data[offset + 1];
+ tagnum <<= 8;
+ tagnum += exif_data[offset];
+ }
+ if (tagnum == 0x0112)
+ break; /* found Orientation Tag */
+ if (--number_of_tags == 0)
+ return -1;
+ offset += 12;
+ }
+
+ /* Get the Orientation value */
+ if (is_motorola == 1) {
+ if (exif_data[offset + 8] != 0)
+ return -1;
+ set_flag = exif_data[offset + 9];
+ } else {
+ if (exif_data[offset + 9] != 0)
+ return -1;
+ set_flag = exif_data[offset + 8];
+ }
+ if (set_flag > 8)
+ return -1;
+
+ return set_flag;
+ }
+
+ /**
+ * Check that the class can operate (for instance, that all the required
+ * libraries or frameworks are present).
+ *
+ * @return TRUE if it works
+ */
+ abstract protected boolean check();
+
+ /**
+ * Create a new {@link ImageUtils}.
+ *
+ * @return the {@link ImageUtils}
+ */
+ private static ImageUtils newObject() {
+ for (String clazz : new String[] { "be.nikiroo.utils.ui.ImageUtilsAwt",
+ "be.nikiroo.utils.android.ImageUtilsAndroid" }) {
+ try {
+ ImageUtils obj = (ImageUtils) SerialUtils.createObject(clazz);
+ if (obj.check()) {
+ return obj;
+ }
+ } catch (Throwable e) {
+ }
+ }
+
+ return null;
+ }
+}