/**
* decode palette from the input stream
*
* @param pic SubPicture object containing info about the current caption
* @return
* @throws CoreException
*/
private Palette decodePalette(SubPictureBD pic) throws CoreException {
boolean fadeOut = false;
int paletteIndex;
List<PaletteInfo> paletteInfos = pic.getPalettes().get(pic.getImageObject().getPaletteID());
if (paletteInfos == null) {
throw new CoreException("Palette ID out of bounds.");
}
Palette palette = new Palette(256, Core.usesBT601());
// by definition, index 0xff is always completely transparent
// also all entries must be fully transparent after initialization
try {
for (PaletteInfo paletteInfo : paletteInfos) {
int index = paletteInfo.getPaletteOffset();
for (int i = 0; i < paletteInfo.getPaletteSize(); i++) {
// each palette entry consists of 5 bytes
paletteIndex = buffer.getByte(index);
int y = buffer.getByte(++index);
int cr, cb;
if (configuration.isSwapCrCb()) {
cb = buffer.getByte(++index);
cr = buffer.getByte(++index);
} else {
cr = buffer.getByte(++index);
cb = buffer.getByte(++index);
}
int alpha = buffer.getByte(++index);
int alphaOld = palette.getAlpha(paletteIndex);
// avoid fading out
if (alpha >= alphaOld) {
if (alpha
< configuration
.getAlphaCrop()) { // to not mess with scaling algorithms, make transparent
// color black
y = 16;
cr = 128;
cb = 128;
}
palette.setAlpha(paletteIndex, alpha);
} else {
fadeOut = true;
}
palette.setYCbCr(paletteIndex, y, cb, cr);
index++;
}
}
if (fadeOut) {
logger.warn("fade out detected -> patched palette\n");
}
return palette;
} catch (FileBufferException ex) {
throw new CoreException(ex.getMessage());
}
}
/**
* Decode caption from the input stream.
*
* @param subPictureBD SubPicture object containing info about the caption
* @param transparentColorIndex index of the transparent color
* @return bitmap of the decoded caption
* @throws CoreException
*/
private Bitmap decodeImage(SubPictureBD subPictureBD, int transparentColorIndex)
throws CoreException {
int width = subPictureBD.getImageWidth();
int height = subPictureBD.getImageHeight();
// always decode image obj 0, start with first entry in fragment list
ImageObjectFragment imageObjectFragment =
subPictureBD.getImageObject().getFragmentList().get(0);
long startOfs = imageObjectFragment.getImageBufferOfs();
if (width > subPictureBD.getWidth() || height > subPictureBD.getHeight()) {
throw new CoreException(
"Subpicture too large: "
+ width
+ "x"
+ height
+ " at offset "
+ ToolBox.toHexLeftZeroPadded(startOfs, 8));
}
Bitmap bm = new Bitmap(width, height, (byte) transparentColorIndex);
int b;
int index = 0;
int ofs = 0;
int size;
int xpos = 0;
try {
// just for multi-packet support, copy all of the image data in one common buffer
byte[] buffer = new byte[subPictureBD.getImageObject().getBufferSize()];
index = 0;
for (ImageObjectFragment fragment : subPictureBD.getImageObject().getFragmentList()) {
// copy data of all packet to one common buffer
imageObjectFragment = fragment;
for (int i = 0; i < imageObjectFragment.getImagePacketSize(); i++) {
buffer[index + i] =
(byte) this.buffer.getByte(imageObjectFragment.getImageBufferOfs() + i);
}
index += imageObjectFragment.getImagePacketSize();
}
index = 0;
do {
b = buffer[index++] & 0xff;
if (b == 0) {
b = buffer[index++] & 0xff;
if (b == 0) {
// next line
ofs = (ofs / width) * width;
if (xpos < width) {
ofs += width;
}
xpos = 0;
} else {
if ((b & 0xC0) == 0x40) {
// 00 4x xx -> xxx zeroes
size = ((b - 0x40) << 8) + (buffer[index++] & 0xff);
for (int i = 0; i < size; i++) {
bm.getInternalBuffer()[ofs++] = 0; /*(byte)b;*/
}
xpos += size;
} else if ((b & 0xC0) == 0x80) {
// 00 8x yy -> x times value y
size = (b - 0x80);
b = buffer[index++] & 0xff;
for (int i = 0; i < size; i++) {
bm.getInternalBuffer()[ofs++] = (byte) b;
}
xpos += size;
} else if ((b & 0xC0) != 0) {
// 00 cx yy zz -> xyy times value z
size = ((b - 0xC0) << 8) + (buffer[index++] & 0xff);
b = buffer[index++] & 0xff;
for (int i = 0; i < size; i++) {
bm.getInternalBuffer()[ofs++] = (byte) b;
}
xpos += size;
} else {
// 00 xx -> xx times 0
for (int i = 0; i < b; i++) {
bm.getInternalBuffer()[ofs++] = 0;
}
xpos += b;
}
}
} else {
bm.getInternalBuffer()[ofs++] = (byte) b;
xpos++;
}
} while (index < buffer.length);
return bm;
} catch (FileBufferException ex) {
throw new CoreException(ex.getMessage());
} catch (ArrayIndexOutOfBoundsException ex) {
logger.warn(
"Problems during RLE decoding of picture OBJ at offset "
+ ToolBox.toHexLeftZeroPadded(startOfs + index, 8)
+ "\n");
return bm;
}
}