* Implements decoding of MPEG Audio Layer I frames.
*/
-
class LayerIDecoder implements FrameDecoder {
-
protected Bitstream stream;
-
+
protected Header header;
-
+
protected SynthesisFilter filter1;
-
+
protected SynthesisFilter filter2;
-
+
protected Obuffer buffer;
-
+
protected int which_channels;
-
+
protected int mode;
-
protected int num_subbands;
-
+
protected Subband[] subbands;
-
protected Crc16 crc = null; // new Crc16[1] to enable CRC checking.
public LayerIDecoder() {
crc = new Crc16();
}
- public void create( Bitstream stream0, Header header0,
- SynthesisFilter filtera, SynthesisFilter filterb,
- Obuffer buffer0, int which_ch0) {
+ public void create(Bitstream stream0, Header header0, SynthesisFilter filtera, SynthesisFilter filterb, Obuffer buffer0, int which_ch0) {
stream = stream0;
header = header0;
filter1 = filtera;
}
protected void createSubbands() {
- int i;
+ int i;
if (mode == Header.SINGLE_CHANNEL) {
for (i = 0; i < num_subbands; ++i) {
subbands[i] = new SubbandLayer1(i);
protected void readAllocation() throws DecoderException {
// start to read audio data:
- for ( int i = 0; i < num_subbands; ++i)
+ for (int i = 0; i < num_subbands; ++i)
subbands[i].read_allocation(stream, header, crc);
}
}
protected void readScaleFactors() {
- for ( int i = 0; i < num_subbands; ++i)
+ for (int i = 0; i < num_subbands; ++i)
subbands[i].read_scalefactor(stream, header);
}
-
protected void readSampleData() {
- boolean read_ready = false;
- boolean write_ready = false;
+ boolean read_ready = false;
+ boolean write_ready = false;
- int mode = header.mode(); // header.mode() will return
- // DELTA(THIS)
+ int mode = header.mode(); // header.mode() will return
+ // DELTA(THIS)
- int i;
+ int i;
do {
for (i = 0; i < num_subbands; ++i) {
* Class for layer I subbands in single channel mode. Used for single channel
* mode and in derived class for intensity stereo mode
*/
-
-
+
static class SubbandLayer1 extends Subband {
// Factors and offsets for sample requantization
- public static final float table_factor[] = { 0.0f, (1.0f / 2.0f) * (4.0f / 3.0f),
- (1.0f / 4.0f) * (8.0f / 7.0f), (1.0f / 8.0f) * (16.0f / 15.0f),
- (1.0f / 16.0f) * (32.0f / 31.0f), (1.0f / 32.0f) * (64.0f / 63.0f),
- (1.0f / 64.0f) * (128.0f / 127.0f), (1.0f / 128.0f) * (256.0f / 255.0f),
- (1.0f / 256.0f) * (512.0f / 511.0f), (1.0f / 512.0f) * (1024.0f / 1023.0f),
- (1.0f / 1024.0f) * (2048.0f / 2047.0f), (1.0f / 2048.0f) * (4096.0f / 4095.0f),
- (1.0f / 4096.0f) * (8192.0f / 8191.0f), (1.0f / 8192.0f) * (16384.0f / 16383.0f),
- (1.0f / 16384.0f) * (32768.0f / 32767.0f) };
-
- public static final float table_offset[] = { 0.0f, ((1.0f / 2.0f) - 1.0f) * (4.0f / 3.0f),
- ((1.0f / 4.0f) - 1.0f) * (8.0f / 7.0f), ((1.0f / 8.0f) - 1.0f) * (16.0f / 15.0f),
- ((1.0f / 16.0f) - 1.0f) * (32.0f / 31.0f), ((1.0f / 32.0f) - 1.0f) * (64.0f / 63.0f),
- ((1.0f / 64.0f) - 1.0f) * (128.0f / 127.0f), ((1.0f / 128.0f) - 1.0f) * (256.0f / 255.0f),
- ((1.0f / 256.0f) - 1.0f) * (512.0f / 511.0f),
- ((1.0f / 512.0f) - 1.0f) * (1024.0f / 1023.0f),
- ((1.0f / 1024.0f) - 1.0f) * (2048.0f / 2047.0f),
- ((1.0f / 2048.0f) - 1.0f) * (4096.0f / 4095.0f),
- ((1.0f / 4096.0f) - 1.0f) * (8192.0f / 8191.0f),
- ((1.0f / 8192.0f) - 1.0f) * (16384.0f / 16383.0f),
- ((1.0f / 16384.0f) - 1.0f) * (32768.0f / 32767.0f) };
-
-
+ public static final float table_factor[] = { 0.0f, (1.0f / 2.0f) * (4.0f / 3.0f), (1.0f / 4.0f) * (8.0f / 7.0f), (1.0f / 8.0f) * (16.0f / 15.0f), (1.0f / 16.0f) * (32.0f / 31.0f), (1.0f / 32.0f) * (64.0f / 63.0f), (1.0f / 64.0f) * (128.0f / 127.0f), (1.0f / 128.0f) * (256.0f / 255.0f), (1.0f / 256.0f) * (512.0f / 511.0f), (1.0f / 512.0f) * (1024.0f / 1023.0f), (1.0f / 1024.0f) * (2048.0f / 2047.0f), (1.0f / 2048.0f) * (4096.0f / 4095.0f), (1.0f / 4096.0f) * (8192.0f / 8191.0f), (1.0f / 8192.0f) * (16384.0f / 16383.0f), (1.0f / 16384.0f) * (32768.0f / 32767.0f) };
+
+ public static final float table_offset[] = { 0.0f, ((1.0f / 2.0f) - 1.0f) * (4.0f / 3.0f), ((1.0f / 4.0f) - 1.0f) * (8.0f / 7.0f), ((1.0f / 8.0f) - 1.0f) * (16.0f / 15.0f), ((1.0f / 16.0f) - 1.0f) * (32.0f / 31.0f), ((1.0f / 32.0f) - 1.0f) * (64.0f / 63.0f), ((1.0f / 64.0f) - 1.0f) * (128.0f / 127.0f), ((1.0f / 128.0f) - 1.0f) * (256.0f / 255.0f), ((1.0f / 256.0f) - 1.0f) * (512.0f / 511.0f), ((1.0f / 512.0f) - 1.0f) * (1024.0f / 1023.0f), ((1.0f / 1024.0f) - 1.0f) * (2048.0f / 2047.0f), ((1.0f / 2048.0f) - 1.0f) * (4096.0f / 4095.0f), ((1.0f / 4096.0f) - 1.0f) * (8192.0f / 8191.0f), ((1.0f / 8192.0f) - 1.0f) * (16384.0f / 16383.0f), ((1.0f / 16384.0f) - 1.0f) * (32768.0f / 32767.0f) };
+
protected int subbandnumber;
-
+
protected int samplenumber;
-
+
protected int allocation;
-
+
protected float scalefactor;
-
+
protected int samplelength;
-
+
protected float sample;
-
+
protected float factor;
-
+
protected float offset;
/**
* Construtor.
*/
- public SubbandLayer1( int subbandnumber) {
+ public SubbandLayer1(int subbandnumber) {
this.subbandnumber = subbandnumber;
samplenumber = 0;
}
/**
*
*/
- //
-
- public void read_allocation( Bitstream stream,
- Header header, Crc16 crc)
- throws DecoderException {
+ //
+
+ public void read_allocation(Bitstream stream, Header header, Crc16 crc) throws DecoderException {
if ((allocation = stream.get_bits(4)) == 15) {
// CGJ: catch this condition and throw appropriate exception
/**
*
*/
- public void read_scalefactor( Bitstream stream, Header header) {
+ public void read_scalefactor(Bitstream stream, Header header) {
if (allocation != 0)
scalefactor = scalefactors[stream.get_bits(6)];
}
// ssjava
-
-
- public boolean read_sampledata( Bitstream stream) {
+
+ public boolean read_sampledata(Bitstream stream) {
if (allocation != 0) {
sample = (float) (stream.get_bits(samplelength));
}
return false;
}
- //
-
- public boolean put_next_sample( int channels,
- SynthesisFilter filter1,
- SynthesisFilter filter2) {
+ //
+
+ public boolean put_next_sample(int channels, SynthesisFilter filter1, SynthesisFilter filter2) {
if ((allocation != 0) && (channels != OutputChannels.RIGHT_CHANNEL)) {
- float scaled_sample =
- (sample * factor + offset) * scalefactor;
+ float scaled_sample = (sample * factor + offset) * scalefactor;
filter1.input_sample(scaled_sample, subbandnumber);
}
return true;
/**
* Class for layer I subbands in joint stereo mode.
*/
-
-
+
static class SubbandLayer1IntensityStereo extends SubbandLayer1 {
-
+
protected float channel2_scalefactor;
/**
* Constructor
*/
- public SubbandLayer1IntensityStereo( int subbandnumber) {
+ public SubbandLayer1IntensityStereo(int subbandnumber) {
super(subbandnumber);
}
/**
*
*/
-
- public void read_allocation( Bitstream stream, Header header,
- Crc16 crc) throws DecoderException {
+
+ public void read_allocation(Bitstream stream, Header header, Crc16 crc) throws DecoderException {
super.read_allocation(stream, header, crc);
}
/**
*
*/
- public void read_scalefactor( Bitstream stream, Header header) {
+ public void read_scalefactor(Bitstream stream, Header header) {
if (allocation != 0) {
scalefactor = scalefactors[stream.get_bits(6)];
channel2_scalefactor = scalefactors[stream.get_bits(6)];
}
}
- public boolean read_sampledata( Bitstream stream) {
+ public boolean read_sampledata(Bitstream stream) {
return super.read_sampledata(stream);
}
- public boolean put_next_sample( int channels, SynthesisFilter filter1,
- SynthesisFilter filter2) {
+ public boolean put_next_sample(int channels, SynthesisFilter filter1, SynthesisFilter filter2) {
if (allocation != 0) {
sample = sample * factor + offset; // requantization
if (channels == OutputChannels.BOTH_CHANNELS) {
- float sample1 = sample * scalefactor;
- float sample2 = sample * channel2_scalefactor;
+ float sample1 = sample * scalefactor;
+ float sample2 = sample * channel2_scalefactor;
filter1.input_sample(sample1, subbandnumber);
filter2.input_sample(sample2, subbandnumber);
} else if (channels == OutputChannels.LEFT_CHANNEL) {
- float sample1 = sample * scalefactor;
+ float sample1 = sample * scalefactor;
filter1.input_sample(sample1, subbandnumber);
} else {
- float sample2 = sample * channel2_scalefactor;
+ float sample2 = sample * channel2_scalefactor;
filter1.input_sample(sample2, subbandnumber);
}
}
/**
* Class for layer I subbands in stereo mode.
*/
-
-
+
static class SubbandLayer1Stereo extends SubbandLayer1 {
-
+
protected int channel2_allocation;
-
+
protected float channel2_scalefactor;
-
+
protected int channel2_samplelength;
-
+
protected float channel2_sample;
-
+
protected float channel2_factor;
-
+
protected float channel2_offset;
/**
* Constructor
*/
- public SubbandLayer1Stereo( int subbandnumber) {
+ public SubbandLayer1Stereo(int subbandnumber) {
super(subbandnumber);
}
*
*/
// ssjava
- public void read_allocation( Bitstream stream,
- Header header, Crc16 crc)
- throws DecoderException {
+ public void read_allocation(Bitstream stream, Header header, Crc16 crc) throws DecoderException {
allocation = stream.get_bits(4);
channel2_allocation = stream.get_bits(4);
if (crc != null) {
/**
*
*/
- public void read_scalefactor( Bitstream stream, Header header) {
+ public void read_scalefactor(Bitstream stream, Header header) {
if (allocation != 0)
scalefactor = scalefactors[stream.get_bits(6)];
if (channel2_allocation != 0)
/**
*
*/
-
- public boolean read_sampledata( Bitstream stream) {
- boolean returnvalue =
- super.read_sampledata(stream);
+
+ public boolean read_sampledata(Bitstream stream) {
+ boolean returnvalue = super.read_sampledata(stream);
if (channel2_allocation != 0) {
channel2_sample = (float) (stream.get_bits(channel2_samplelength));
}
/**
*
*/
-
- public boolean put_next_sample( int channels, SynthesisFilter filter1,
- SynthesisFilter filter2) {
+
+ public boolean put_next_sample(int channels, SynthesisFilter filter1, SynthesisFilter filter2) {
super.put_next_sample(channels, filter1, filter2);
if ((channel2_allocation != 0) && (channels != OutputChannels.LEFT_CHANNEL)) {
- float sample2 =
- (channel2_sample * channel2_factor + channel2_offset) * channel2_scalefactor;
+ float sample2 = (channel2_sample * channel2_factor + channel2_offset) * channel2_scalefactor;
if (channels == OutputChannels.BOTH_CHANNELS)
filter2.input_sample(sample2, subbandnumber);
else
projects / IRC.git / blobdiff