/** Peek into the parentInput's input stream and if the next item
* is a NIFF stem, return a new Stem. Otherwise,
* return null and leave the input stream unchanged.
*
* @param parentInput the parent RIFF object being used to read the input stream
*/
public static Stem maybeNew(Riff parentInput)
{
if (!parentInput.peekFOURCC().Equals(RIFF_ID))
return null;
return newInstance(parentInput);
}
/** Peek into the parentInput's input stream and if the next item
* is a NIFF String Table, then decode it and store it in the
* root RIFFForNIFF object.
* If the next item is not a NIFF String Table, do nothing
* and leave the input stream unchanged.
*
* @param parentInput the parent RIFF object being used to read the input stream.
* If parentInput.getParent() is not of type RIFFForNIFF, then this
* moves the input past the String Table but does not store it.
* @return true if the String Table was processed, false if this is
* not a String Table.
*/
static public bool maybeDecode(Riff parentInput)
{
if (!parentInput.peekFOURCC().Equals(RIFF_ID))
{
return(false);
}
Riff riffInput = new Riff(parentInput, RIFF_ID);
if (!(parentInput.getParent() is RiffForNiff))
{
// There is no place to store the data
riffInput.skipRemaining();
return(true);
}
RiffForNiff riffForNiff = (RiffForNiff)parentInput.getParent();
// Read the entire string table into a byte array
byte[] stringTable = new byte[riffInput.getBytesRemaining()];
for (int i = 0; i < stringTable.Length; ++i)
{
stringTable[i] = (byte)riffInput.readBYTE();
}
riffForNiff.setStringTable(stringTable);
// This skips possible pad byte
riffInput.skipRemaining();
return(true);
}
/** Peek into the parentInput's input stream and if the next item
* is a NIFF rest, return a new Rest. Otherwise,
* return null and leave the input stream unchanged.
*
* @param parentInput the parent RIFF object being used to read the input stream
*/
static public Rest maybeNew(Riff parentInput)
{
if (!parentInput.peekFOURCC().Equals(RIFF_ID))
{
return(null);
}
return(newInstance(parentInput));
}
/** Peek into the parentInput's input stream and if the next item
* is a NIFF time slice with any type other than MEASURE_START (presumably
* type EVENT), return a new TimeSlice. Otherwise,
* return null and leave the input stream unchanged.
*
* @param parentInput the parent RIFF object being used to read the input stream
*/
public static TimeSlice maybeNew(Riff parentInput)
{
if (!parentInput.peekFOURCC().Equals(RIFF_ID))
return null;
// We must also ensure that this is not a MEASURE_START time slice
if (parentInput.peekFirstChunkBYTE() == MEASURE_START)
return null;
return newInstance(parentInput);
}
/** Peek into the parentInput's input stream and if the next item
* is a NIFF time slice with type MEASURE_START, return a new
* MeasureStartTimeSlice. Otherwise,
* return null and leave the input stream unchanged.
*
* @param parentInput the parent RIFF object being used to read the input stream
*/
static public MeasureStartTimeSlice maybeNew(Riff parentInput)
{
if (!parentInput.peekFOURCC().Equals(RIFF_ID))
{
return(null);
}
// We must also ensure that this is a MEASURE_START time slice
if (parentInput.peekFirstChunkBYTE() != MEASURE_START)
{
return(null);
}
return(newInstance(parentInput));
}
/** This reads event TimeSlice chunks from parentInput's input stream until the next
* measure start time slice or no more bytesRemaining in the parentInput,
* adding the TimeSlice objects to the measureStart's time slice list.
* When this reads the TimeSlice, it also adds the subsequent music
* symbols to it.
*
* @param parentInput the parent RIFF object being used to read the input stream
* @param measureStart the MeasureStartTimeSlice to which TimeSlice
* objects are added.
* @see TimeSlice
*/
public static void addTimeSlices(Riff parentInput, MeasureStartTimeSlice measureStart)
{
if (parentInput.getBytesRemaining() <= 0)
// This is a measure start time slice with nothing after it in the staff
return;
if (parentInput.peekFOURCC().Equals(RIFF_ID) &&
parentInput.peekFirstChunkBYTE() == MEASURE_START)
// The next chunk is already the start of a new measure
return;
TimeSlice timeSlice = RiffTimeSlice.maybeNew(parentInput);
if (timeSlice == null)
// For some reason, the first chunk after the measure start
// time slice is not an event time slice. Create a fake one with
// start time of 0/1.
// DEBUG: should mock up an input file and test this.
timeSlice = new TimeSlice(new Rational(0, 1), null);
while (true) {
if (measureStart.getTimeSliceCount() > 0 &&
measureStart.getTimeSlice
(measureStart.getTimeSliceCount() - 1).getStartTime().Equals
(timeSlice.getStartTime()))
// This new time slice start time is the same as the last one,
// so just continue using the last one.
// DEBUG: this still doesn't ensure increasing order
// DEBUG: This discards the tags in the newly read time slice
timeSlice =
measureStart.getTimeSlice(measureStart.getTimeSliceCount() - 1);
else
measureStart.addTimeSlice(timeSlice);
// Read music symbols until the next time slice or
// end of the staff.
RiffTimeSlice.addMusicSymbols(parentInput, timeSlice);
if (parentInput.getBytesRemaining() <= 0)
// reached the end of the staff
break;
// We know the next chunk is a time slice. Check whether it is
// a measure start.
if (parentInput.peekFirstChunkBYTE() == MEASURE_START)
// The next chunk is the start of a new measure
break;
// We have now ensured that the next chunk is an event time slice.
timeSlice = RiffTimeSlice.newInstance(parentInput);
}
}
/** This reads chunks from parentInput's input stream until the next
* NIFF time slice or no more bytesRemaining in the input,
* adding the chunks to the timeSlice's music symbol list. If a music
* symbol is not recognized, this skips it.
* This stops at either a measure start or an event time slice.
*
* @param parentInput the parent RIFF object being used to read the input stream
* @param timeSlice the TimeSlice to which MusicSymbol objects are added.
* @see MusicSymbol
*/
public static void addMusicSymbols(Riff parentInput, TimeSlice timeSlice)
{
while (parentInput.getBytesRemaining() > 0) {
if (parentInput.peekFOURCC().Equals(RIFF_ID))
// encoutered the next time slice, so quit
// Note that this stops at either a measure start or an event time slice.
return;
MusicSymbol musicSymbol = maybeNewAnyMusicSymbol(parentInput);
if (musicSymbol != null)
timeSlice.addMusicSymbol(musicSymbol);
else
// Did not recognize the music symbol, so skip
parentInput.skipChunk();
}
}
/** This reads chunks from parentInput's input stream until the next
* NIFF time slice or no more bytesRemaining in the input,
* adding the chunks to the timeSlice's music symbol list. If a music
* symbol is not recognized, this skips it.
* This stops at either a measure start or an event time slice.
*
* @param parentInput the parent RIFF object being used to read the input stream
* @param timeSlice the TimeSlice to which MusicSymbol objects are added.
* @see MusicSymbol
*/
static public void addMusicSymbols(Riff parentInput, TimeSlice timeSlice)
{
while (parentInput.getBytesRemaining() > 0)
{
if (parentInput.peekFOURCC().Equals(RIFF_ID))
{
// encoutered the next time slice, so quit
// Note that this stops at either a measure start or an event time slice.
return;
}
MusicSymbol musicSymbol = maybeNewAnyMusicSymbol(parentInput);
if (musicSymbol != null)
{
timeSlice.addMusicSymbol(musicSymbol);
}
else
{
// Did not recognize the music symbol, so skip
parentInput.skipChunk();
}
}
}
/** This reads event TimeSlice chunks from parentInput's input stream until the next
* measure start time slice or no more bytesRemaining in the parentInput,
* adding the TimeSlice objects to the measureStart's time slice list.
* When this reads the TimeSlice, it also adds the subsequent music
* symbols to it.
*
* @param parentInput the parent RIFF object being used to read the input stream
* @param measureStart the MeasureStartTimeSlice to which TimeSlice
* objects are added.
* @see TimeSlice
*/
static public void addTimeSlices
(Riff parentInput, MeasureStartTimeSlice measureStart)
{
if (parentInput.getBytesRemaining() <= 0)
{
// This is a measure start time slice with nothing after it in the staff
return;
}
if (parentInput.peekFOURCC().Equals(RIFF_ID) &&
parentInput.peekFirstChunkBYTE() == MEASURE_START)
{
// The next chunk is already the start of a new measure
return;
}
TimeSlice timeSlice = RiffTimeSlice.maybeNew(parentInput);
if (timeSlice == null)
{
// For some reason, the first chunk after the measure start
// time slice is not an event time slice. Create a fake one with
// start time of 0/1.
// DEBUG: should mock up an input file and test this.
timeSlice = new TimeSlice(new Rational(0, 1), null);
}
while (true)
{
if (measureStart.getTimeSliceCount() > 0 &&
measureStart.getTimeSlice
(measureStart.getTimeSliceCount() - 1).getStartTime().Equals
(timeSlice.getStartTime()))
{
// This new time slice start time is the same as the last one,
// so just continue using the last one.
// DEBUG: this still doesn't ensure increasing order
// DEBUG: This discards the tags in the newly read time slice
timeSlice =
measureStart.getTimeSlice(measureStart.getTimeSliceCount() - 1);
}
else
{
measureStart.addTimeSlice(timeSlice);
}
// Read music symbols until the next time slice or
// end of the staff.
RiffTimeSlice.addMusicSymbols(parentInput, timeSlice);
if (parentInput.getBytesRemaining() <= 0)
{
// reached the end of the staff
break;
}
// We know the next chunk is a time slice. Check whether it is
// a measure start.
if (parentInput.peekFirstChunkBYTE() == MEASURE_START)
{
// The next chunk is the start of a new measure
break;
}
// We have now ensured that the next chunk is an event time slice.
timeSlice = RiffTimeSlice.newInstance(parentInput);
}
}
/** Peek into the parentInput's input stream and if the next item
* is a NIFF String Table, then decode it and store it in the
* root RIFFForNIFF object.
* If the next item is not a NIFF String Table, do nothing
* and leave the input stream unchanged.
*
* @param parentInput the parent RIFF object being used to read the input stream.
* If parentInput.getParent() is not of type RIFFForNIFF, then this
* moves the input past the String Table but does not store it.
* @return true if the String Table was processed, false if this is
* not a String Table.
*/
public static bool maybeDecode(Riff parentInput)
{
if (!parentInput.peekFOURCC().Equals(RIFF_ID))
return false;
Riff riffInput = new Riff(parentInput, RIFF_ID);
if (!(parentInput.getParent() is RiffForNiff)) {
// There is no place to store the data
riffInput.skipRemaining();
return true;
}
RiffForNiff riffForNiff = (RiffForNiff)parentInput.getParent();
// Read the entire string table into a byte array
byte[] stringTable = new byte[riffInput.getBytesRemaining()];
for (int i = 0; i < stringTable.Length; ++i)
stringTable[i] = (byte)riffInput.readBYTE();
riffForNiff.setStringTable(stringTable);
// This skips possible pad byte
riffInput.skipRemaining();
return true;
}
