package org.mp4parser.examples.metadata;
import org.mp4parser.Box;
import org.mp4parser.Container;
import org.mp4parser.IsoFile;
import org.mp4parser.boxes.apple.AppleItemListBox;
import org.mp4parser.boxes.apple.AppleNameBox;
import org.mp4parser.boxes.iso14496.part12.*;
import org.mp4parser.tools.Path;
import java.io.*;
import java.nio.ByteBuffer;
import java.nio.channels.Channels;
import java.nio.channels.FileChannel;
import java.util.List;
/**
* Change metadata and make sure chunkoffsets are corrected.
*/
public class MetaDataInsert {
public static void main(String[] args) throws IOException {
MetaDataInsert cmd = new MetaDataInsert();
cmd.writeRandomMetadata("c:\\content\\Mobile_H264 - Kopie.mp4",
"lore ipsum tralalala");
}
public FileChannel splitFileAndInsert(File f, long pos, long length) throws IOException {
FileChannel read = new RandomAccessFile(f, "r").getChannel();
File tmp = File.createTempFile("ChangeMetaData", "splitFileAndInsert");
FileChannel tmpWrite = new RandomAccessFile(tmp, "rw").getChannel();
read.position(pos);
tmpWrite.transferFrom(read, 0, read.size() - pos);
read.close();
FileChannel write = new RandomAccessFile(f, "rw").getChannel();
write.position(pos + length);
tmpWrite.position(0);
long transferred = 0;
while ((transferred += tmpWrite.transferTo(0, tmpWrite.size() - transferred, write)) != tmpWrite.size()) {
System.out.println(transferred);
}
System.out.println(transferred);
tmpWrite.close();
tmp.delete();
return write;
}
private boolean needsOffsetCorrection(IsoFile isoFile) {
if (Path.getPath(isoFile, "moov[0]/mvex[0]") != null) {
// Fragmented files don't need a correction
return false;
} else {
// no correction needed if mdat is before moov as insert into moov want change the offsets of mdat
for (Box box : isoFile.getBoxes()) {
if ("moov".equals(box.getType())) {
return true;
}
if ("mdat".equals(box.getType())) {
return false;
}
}
throw new RuntimeException("I need moov or mdat. Otherwise all this doesn't make sense");
}
}
public void writeRandomMetadata(String videoFilePath, String title) throws IOException {
File videoFile = new File(videoFilePath);
if (!videoFile.exists()) {
throw new FileNotFoundException("File " + videoFilePath + " not exists");
}
if (!videoFile.canWrite()) {
throw new IllegalStateException("No write permissions to file " + videoFilePath);
}
IsoFile isoFile = new IsoFile(videoFilePath);
MovieBox moov = isoFile.getBoxes(MovieBox.class).get(0);
FreeBox freeBox = findFreeBox(moov);
boolean correctOffset = needsOffsetCorrection(isoFile);
long sizeBefore = moov.getSize();
long offset = 0;
for (Box box : isoFile.getBoxes()) {
if ("moov".equals(box.getType())) {
break;
}
offset += box.getSize();
}
// Create structure or just navigate to Apple List Box.
UserDataBox userDataBox;
if ((userDataBox = Path.getPath(moov, "udta")) == null) {
userDataBox = new UserDataBox();
moov.addBox(userDataBox);
}
MetaBox metaBox;
if ((metaBox = Path.getPath(userDataBox, "meta")) == null) {
metaBox = new MetaBox();
HandlerBox hdlr = new HandlerBox();
hdlr.setHandlerType("mdir");
metaBox.addBox(hdlr);
userDataBox.addBox(metaBox);
}
AppleItemListBox ilst;
if ((ilst = Path.getPath(metaBox, "ilst")) == null) {
ilst = new AppleItemListBox();
metaBox.addBox(ilst);
}
if (freeBox == null) {
freeBox = new FreeBox(128 * 1024);
metaBox.addBox(freeBox);
}
// Got Apple List Box
AppleNameBox nam;
if ((nam = Path.getPath(ilst, "©nam")) == null) {
nam = new AppleNameBox();
}
nam.setDataCountry(0);
nam.setDataLanguage(0);
nam.setValue(title);
ilst.addBox(nam);
long sizeAfter = moov.getSize();
long diff = sizeAfter - sizeBefore;
// This is the difference of before/after
// can we compensate by resizing a Free Box we have found?
if (freeBox.getData().limit() > diff) {
// either shrink or grow!
freeBox.setData(ByteBuffer.allocate((int) (freeBox.getData().limit() - diff)));
sizeAfter = moov.getSize();
diff = sizeAfter - sizeBefore;
}
if (correctOffset && diff != 0) {
correctChunkOffsets(moov, diff);
}
BetterByteArrayOutputStream baos = new BetterByteArrayOutputStream();
moov.getBox(Channels.newChannel(baos));
isoFile.close();
FileChannel fc;
if (diff != 0) {
// this is not good: We have to insert bytes in the middle of the file
// and this costs time as it requires re-writing most of the file's data
fc = splitFileAndInsert(videoFile, offset, sizeAfter - sizeBefore);
} else {
// simple overwrite of something with the file
fc = new RandomAccessFile(videoFile, "rw").getChannel();
}
fc.position(offset);
fc.write(ByteBuffer.wrap(baos.getBuffer(), 0, baos.size()));
fc.close();
}
FreeBox findFreeBox(Container c) {
for (Box box : c.getBoxes()) {
System.err.println(box.getType());
if (box instanceof FreeBox) {
return (FreeBox) box;
}
if (box instanceof Container) {
FreeBox freeBox = findFreeBox((Container) box);
if (freeBox != null) {
return freeBox;
}
}
}
return null;
}
private void correctChunkOffsets(MovieBox movieBox, long correction) {
List<ChunkOffsetBox> chunkOffsetBoxes = Path.getPaths((Box) movieBox, "trak/mdia[0]/minf[0]/stbl[0]/stco[0]");
if (chunkOffsetBoxes.isEmpty()) {
chunkOffsetBoxes = Path.getPaths((Box) movieBox, "trak/mdia[0]/minf[0]/stbl[0]/st64[0]");
}
for (ChunkOffsetBox chunkOffsetBox : chunkOffsetBoxes) {
long[] cOffsets = chunkOffsetBox.getChunkOffsets();
for (int i = 0; i < cOffsets.length; i++) {
cOffsets[i] += correction;
}
}
}
private static class BetterByteArrayOutputStream extends ByteArrayOutputStream {
byte[] getBuffer() {
return buf;
}
}
}