IIOMetadataNode getNativeNode() {
IIOMetadataNode node = new IIOMetadataNode("dqt");
for (int i = 0; i < tables.size(); i++) {
Qtable table = (Qtable) tables.get(i);
node.appendChild(table.getNativeNode());
}
return node;
}
void print() {
printTag("DQT");
System.out.println("Num tables: " + Integer.toString(tables.size()));
for (int i = 0; i < tables.size(); i++) {
Qtable table = (Qtable) tables.get(i);
table.print();
}
System.out.println();
}
protected Object clone() {
DQTMarkerSegment newGuy = (DQTMarkerSegment) super.clone();
newGuy.tables = new ArrayList(tables.size());
Iterator iter = tables.iterator();
while (iter.hasNext()) {
Qtable table = (Qtable) iter.next();
newGuy.tables.add(table.clone());
}
return newGuy;
}
protected Object clone() {
Qtable newGuy = null;
try {
newGuy = (Qtable) super.clone();
} catch (CloneNotSupportedException e) {
} // won't happen
if (data != null) {
newGuy.data = (int[]) data.clone();
}
return newGuy;
}
/**
* Assuming the given table was generated by scaling the "standard" visually lossless luminance
* table, extract the scale factor that was used.
*/
Qtable getChromaForLuma(Qtable luma) {
Qtable newGuy = null;
// Determine if the table is all the same values
// if so, use the same table
boolean allSame = true;
for (int i = 1; i < luma.QTABLE_SIZE; i++) {
if (luma.data[i] != luma.data[i - 1]) {
allSame = false;
break;
}
}
if (allSame) {
newGuy = (Qtable) luma.clone();
newGuy.tableID = 1;
} else {
// Otherwise, find the largest coefficient less than 255. This is
// the largest value that we know did not clamp on scaling.
int largestPos = 0;
for (int i = 1; i < luma.QTABLE_SIZE; i++) {
if (luma.data[i] > luma.data[largestPos]) {
largestPos = i;
}
}
// Compute the scale factor by dividing it by the value in the
// same position from the "standard" table.
// If the given table was not generated by scaling the standard,
// the resulting table will still be reasonable, as it will reflect
// a comparable scaling of chrominance frequency response of the
// eye.
float scaleFactor =
((float) (luma.data[largestPos]))
/ ((float) (JPEGQTable.K1Div2Luminance.getTable()[largestPos]));
// generate a new table
JPEGQTable jpegTable = JPEGQTable.K2Div2Chrominance.getScaledInstance(scaleFactor, true);
newGuy = new Qtable(jpegTable, 1);
}
return newGuy;
}
