synthesisfilter.java

java处理声音文件

				pcm_sample = (float)(((vp[12 + dvp] * dp[0 + ddp]) +
					(vp[11 + dvp] * dp[1 + ddp]) +
					(vp[10 + dvp] * dp[2 + ddp]) +
					(vp[9 + dvp] * dp[3 + ddp]) +
					(vp[8 + dvp] * dp[4 + ddp]) +
					(vp[7 + dvp] * dp[5 + ddp]) +
					(vp[6 + dvp] * dp[6 + ddp]) +
					(vp[5 + dvp] * dp[7 + ddp]) +
					(vp[4 + dvp] * dp[8 + ddp]) +
					(vp[3 + dvp] * dp[9 + ddp]) +
					(vp[2 + dvp] * dp[10 + ddp]) +
					(vp[1 + dvp] * dp[11 + ddp]) +
					(vp[0 + dvp] * dp[12 + ddp]) +
					(vp[15 + dvp] * dp[13 + ddp]) +
					(vp[14 + dvp] * dp[14 + ddp]) +
					(vp[13 + dvp] * dp[15 + ddp])
					) * scalefactor);

            tmpOut[idx++] = pcm_sample;
			} // for
	}
  private void compute_pcm_samples13(Obuffer buffer)
  {
	float[] vp = actual_v;
	float[] dp = d;
	int idx = 0;
	//int inc = v_inc;
	float[] tmpOut = newSamples;
	int ddp =0; int dvp =0;	
	
			// fat chance of having this loop unroll
			for( ddp = 0, dvp = 0;ddp < (32 * 16);ddp += 16, dvp += 16 )
			{
				float pcm_sample;

				pcm_sample = (float)(((vp[13 + dvp] * dp[0 + ddp]) +
					(vp[12 + dvp] * dp[1 + ddp]) +
					(vp[11 + dvp] * dp[2 + ddp]) +
					(vp[10 + dvp] * dp[3 + ddp]) +
					(vp[9 + dvp] * dp[4 + ddp]) +
					(vp[8 + dvp] * dp[5 + ddp]) +
					(vp[7 + dvp] * dp[6 + ddp]) +
					(vp[6 + dvp] * dp[7 + ddp]) +
					(vp[5 + dvp] * dp[8 + ddp]) +
					(vp[4 + dvp] * dp[9 + ddp]) +
					(vp[3 + dvp] * dp[10 + ddp]) +
					(vp[2 + dvp] * dp[11 + ddp]) +
					(vp[1 + dvp] * dp[12 + ddp]) +
					(vp[0 + dvp] * dp[13 + ddp]) +
					(vp[15 + dvp] * dp[14 + ddp]) +
					(vp[14 + dvp] * dp[15 + ddp])
					) * scalefactor);

            tmpOut[idx++] = pcm_sample;
			} // for
  }
  private void compute_pcm_samples14(Obuffer buffer)
  {
	float[] vp = actual_v;
	float[] dp = d;
	int idx = 0;
	//int inc = v_inc;
	float[] tmpOut = newSamples;
	int ddp =0; int dvp =0;
		
			// fat chance of having this loop unroll
			for( ddp = 0, dvp = 0;ddp < (32 * 16);ddp += 16, dvp += 16 )
			{
				float pcm_sample;

				pcm_sample = (float)(((vp[14 + dvp] * dp[0 + ddp]) +
					(vp[13 + dvp] * dp[1 + ddp]) +
					(vp[12 + dvp] * dp[2 + ddp]) +
					(vp[11 + dvp] * dp[3 + ddp]) +
					(vp[10 + dvp] * dp[4 + ddp]) +
					(vp[9 + dvp] * dp[5 + ddp]) +
					(vp[8 + dvp] * dp[6 + ddp]) +
					(vp[7 + dvp] * dp[7 + ddp]) +
					(vp[6 + dvp] * dp[8 + ddp]) +
					(vp[5 + dvp] * dp[9 + ddp]) +
					(vp[4 + dvp] * dp[10 + ddp]) +
					(vp[3 + dvp] * dp[11 + ddp]) +
					(vp[2 + dvp] * dp[12 + ddp]) +
					(vp[1 + dvp] * dp[13 + ddp]) +
					(vp[0 + dvp] * dp[14 + ddp]) +
					(vp[15 + dvp] * dp[15 + ddp])
					) * scalefactor);

            tmpOut[idx++] = pcm_sample;
			} // for
  }
  private void compute_pcm_samples15(Obuffer buffer)
  {
	float[] vp = actual_v;
	float[] dp = d;
	int idx = 0;
	//int inc = v_inc;
	float[] tmpOut = newSamples;
	int ddp =0; int dvp =0;
		
			// fat chance of having this loop unroll
			for( ddp = 0, dvp = 0;ddp < (32 * 16);ddp += 16, dvp += 16 )
			{
				float pcm_sample;

				pcm_sample = (float)(((vp[15 + dvp] * dp[0 + ddp]) +
					(vp[14 + dvp] * dp[1 + ddp]) +
					(vp[13 + dvp] * dp[2 + ddp]) +
					(vp[12 + dvp] * dp[3 + ddp]) +
					(vp[11 + dvp] * dp[4 + ddp]) +
					(vp[10 + dvp] * dp[5 + ddp]) +
					(vp[9 + dvp] * dp[6 + ddp]) +
					(vp[8 + dvp] * dp[7 + ddp]) +
					(vp[7 + dvp] * dp[8 + ddp]) +
					(vp[6 + dvp] * dp[9 + ddp]) +
					(vp[5 + dvp] * dp[10 + ddp]) +
					(vp[4 + dvp] * dp[11 + ddp]) +
					(vp[3 + dvp] * dp[12 + ddp]) +
					(vp[2 + dvp] * dp[13 + ddp]) +
					(vp[1 + dvp] * dp[14 + ddp]) +
					(vp[0 + dvp] * dp[15 + ddp])
					) * scalefactor);

            tmpOut[idx++] = pcm_sample;
			} // for
		}
	 	 	 	 
private void compute_pcm_samples(Obuffer buffer)
{
	
	switch (actual_write_pos)
	{
	case 0: 
		compute_pcm_samples0(buffer);
		break;
	case 1: 
		compute_pcm_samples1(buffer);
		break;
	case 2: 
		compute_pcm_samples2(buffer);
		break;
	case 3: 
		compute_pcm_samples3(buffer);
		break;
	case 4: 
		compute_pcm_samples4(buffer);
		break;
	case 5: 
		compute_pcm_samples5(buffer);
		break;
	case 6: 
		compute_pcm_samples6(buffer);
		break;
	case 7: 
		compute_pcm_samples7(buffer);
		break;
	case 8: 
		compute_pcm_samples8(buffer);
		break;
	case 9: 
		compute_pcm_samples9(buffer);
		break;
	case 10: 
		compute_pcm_samples10(buffer);
		break;
	case 11: 
		compute_pcm_samples11(buffer);
		break;
	case 12: 
		compute_pcm_samples12(buffer);
		break;
	case 13: 
		compute_pcm_samples13(buffer);
		break;
	case 14: 
		compute_pcm_samples14(buffer);
		break;
	case 15: 
		compute_pcm_samples15(buffer);
		break;
	}
		
	if (buffer!=null)
	{
		buffer.appendSamples(channel, newSamples);
	}
	 
/*
	 // MDM: I was considering putting in quality control for
	 // low-spec CPUs, but the performance gain (about 10-15%) 
	 // did not justify the considerable drop in audio quality.
		switch (inc)
		{
		case 16:		 
		    buffer.appendSamples(channel, tmpOut);
		    break;
		case 32:
			for (int i=0; i<16; i++)
			{
				buffer.append(channel, (short)tmpOut[i]);
				buffer.append(channel, (short)tmpOut[i]); 
			}
			break;			
		case 64:
			for (int i=0; i<8; i++)
			{
				buffer.append(channel, (short)tmpOut[i]);
				buffer.append(channel, (short)tmpOut[i]);
				buffer.append(channel, (short)tmpOut[i]);
				buffer.append(channel, (short)tmpOut[i]); 
			}
			break;			
	
		}
*/	 
  }

  /**
   * Calculate 32 PCM samples and put the into the Obuffer-object.
   */
	
  public void calculate_pcm_samples(Obuffer buffer)
  {
	compute_new_v();	
	compute_pcm_samples(buffer);
    
	actual_write_pos = (actual_write_pos + 1) & 0xf;
	actual_v = (actual_v == v1) ? v2 : v1;

	// initialize samples[]:	
    //for (register float *floatp = samples + 32; floatp > samples; )
	// *--floatp = 0.0f;  
	
	// MDM: this may not be necessary. The Layer III decoder always
	// outputs 32 subband samples, but I haven't checked layer I & II.
	for (int p=0;p<32;p++) 
		samples[p] = 0.0f;
  }
  
  
  private static final double MY_PI = 3.14159265358979323846;
  private static final float cos1_64  =(float) (1.0 / (2.0 * Math.cos(MY_PI        / 64.0)));
  private static final float cos3_64  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 3.0  / 64.0)));
  private static final float cos5_64  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 5.0  / 64.0)));
  private static final float cos7_64  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 7.0  / 64.0)));
  private static final float cos9_64  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 9.0  / 64.0)));
  private static final float cos11_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 11.0 / 64.0)));
  private static final float cos13_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 13.0 / 64.0)));
  private static final float cos15_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 15.0 / 64.0)));
  private static final float cos17_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 17.0 / 64.0)));
  private static final float cos19_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 19.0 / 64.0)));
  private static final float cos21_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 21.0 / 64.0)));
  private static final float cos23_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 23.0 / 64.0)));
  private static final float cos25_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 25.0 / 64.0)));
  private static final float cos27_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 27.0 / 64.0)));
  private static final float cos29_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 29.0 / 64.0)));
  private static final float cos31_64 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 31.0 / 64.0)));
  private static final float cos1_32  =(float) (1.0 / (2.0 * Math.cos(MY_PI        / 32.0)));
  private static final float cos3_32  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 3.0  / 32.0)));
  private static final float cos5_32  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 5.0  / 32.0)));
  private static final float cos7_32  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 7.0  / 32.0)));
  private static final float cos9_32  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 9.0  / 32.0)));
  private static final float cos11_32 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 11.0 / 32.0)));
  private static final float cos13_32 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 13.0 / 32.0)));
  private static final float cos15_32 =(float) (1.0 / (2.0 * Math.cos(MY_PI * 15.0 / 32.0)));
  private static final float cos1_16  =(float) (1.0 / (2.0 * Math.cos(MY_PI        / 16.0)));
  private static final float cos3_16  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 3.0  / 16.0)));
  private static final float cos5_16  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 5.0  / 16.0)));
  private static final float cos7_16  =(float) (1.0 / (2.0 * Math.cos(MY_PI * 7.0  / 16.0)));
  private static final float cos1_8   =(float) (1.0 / (2.0 * Math.cos(MY_PI        / 8.0)));
  private static final float cos3_8   =(float) (1.0 / (2.0 * Math.cos(MY_PI * 3.0  / 8.0)));
  private static final float cos1_4   =(float) (1.0 / (2.0 * Math.cos(MY_PI / 4.0)));
  
  // Note: These values are not in the same order
  // as in Annex 3-B.3 of the ISO/IEC DIS 11172-3 
  // private float d[] = {0.000000000, -4.000442505};
  
  private static final float d[] = load_d();
					
  /**
   * Loads the data for the d[] from the resource SFd.ser. 
   * @return the loaded values for d[].
   */
	static private float[] load_d()
	{
		try
		{
			Class elemType = Float.TYPE;
			Object o = JavaLayerUtils.deserializeArrayResource("SFd.ser", elemType, 512);
			return (float[])o;
		}
		catch (IOException ex)
		{
			throw new ExceptionInInitializerError(ex);
		}
		
	}
	
	// The original data for d[]. This data is loaded from a file
	// to reduce the overall package size and to improve performance. 
/*  
  static final float d_data[] = {
  	0.000000000f, -0.000442505f,  0.003250122f, -0.007003784f,
  	0.031082153f, -0.078628540f,  0.100311279f, -0.572036743f,
  	1.144989014f,  0.572036743f,  0.100311279f,  0.078628540f,
  	0.031082153f,  0.007003784f,  0.003250122f,  0.000442505f,
   -0.000015259f, -0.000473022f,  0.003326416f, -0.007919312f,
  	0.030517578f, -0.084182739f,  0.090927124f, -0.600219727f,
  	1.144287109f,  0.543823242f,  0.108856201f,  0.073059082f,
  	0.031478882f,  0.006118774f,  0.003173828f,  0.000396729f,
   -0.000015259f, -0.000534058f,  0.003387451f, -0.008865356f,
  	0.029785156f, -0.089706421f,  0.080688477f, -0.628295898f,
  	1.142211914f,  0.515609741f,  0.116577148f,  0.067520142f,
    0.031738281f,  0.005294800f,  0.003082275f,  0.000366211f,
   -0.000015259f, -0.000579834f,  0.003433228f, -0.009841919f,
    0.028884888f, -0.095169067f,  0.069595337f, -0.656219482f,
  	1.138763428f,  0.487472534f,  0.123474121f,  0.061996460f,
    0.031845093f,  0.004486084f,  0.002990723f,  0.000320435f,
   -0.000015259f, -0.000625610f,  0.003463745f, -0.010848999f,
    0.027801514f, -0.100540161f,  0.057617188f, -0.683914185f,
  	1.133926392f,  0.459472656f,  0.129577637f,  0.056533813f,
  	0.031814575f,  0.003723145f,  0.002899170f,  0.000289917f,
   -0.000015259f, -0.000686646f,  0.003479004f, -0.011886597f,
  	0.026535034f, -0.105819702f,  0.044784546f, -0.711318970f,
  	1.127746582f,  0.431655884f,  0.134887695f,  0.051132202f,
  	0.031661987f,  0.003005981f,  0.002792358f,  0.000259399f,
   -0.000015259f, -0.000747681f,  0.003479004f, -0.012939453f,
  	0.025085449f, -0.110946655f,  0.031082153f, -0.738372803f,
    1.120223999f,  0.404083252f,  0.139450073f,  0.045837402f,
    0.031387329f,  0.002334595f,  0.002685547f,  0.000244141f,
   -0.000030518f, -0.000808716f,  0.003463745f, -0.014022827f,
    0.023422241f, -0.115921021f,  0.016510010f, -0.765029907f,
  	1.111373901f,  0.376800537f,  0.143264771f,  0.040634155f,
    0.031005859f,  0.001693726f,  0.002578735f,  0.000213623f,
   -0.000030518f, -0.000885010f,  0.003417969f, -0.015121460f,
  	0.021575928f, -0.120697021f,  0.001068115f, -0.791213989f,
    1.101211548f,  0.349868774f,  0.146362305f,  0.035552979f,
  	0.030532837f,  0.001098633f,  0.002456665f,  0.000198364f,
   -0.000030518f, -0.000961304f,  0.003372192f, -0.016235352f,
    0.019531250f, -0.125259399f, -0.015228271f, -0.816864014f,
  	1.089782715f,  0.323318481f,  0.148773193f,  0.030609131f,
  	0.029937744f,  0.000549316f,  0.002349854f,  0.000167847f,
   -0.000030518f, -0.001037598f,  0.003280640f, -0.017349243f,
  	0.017257690f, -0.129562378f, -0.032379150f, -0.841949463f,
    1.077117920f,  0.297210693f,  0.150497437f,  0.025817871f,
    0.029281616f,  0.000030518f,  0.002243042f,  0.000152588f,
   -0.000045776f, -0.001113892f,  0.003173828f, -0.018463135f,
  	0.014801025f, -0.133590698f, -0.050354004f, -0.866363525f,
  	1.063217163f,  0.271591187f,  0.151596069f,  0.021179199f,
  	0.028533936f, -0.000442505f,  0.002120972f,  0.000137329f,
   -0.000045776f, -0.001205444f,  0.003051758f, -0.019577026f,
  	0.012115479f, -0.137298584f, -0.069168091f, -0.890090942f,
  	1.048156738f,  0.246505737f,  0.152069092f,  0.016708374f,
  	0.027725220f, -0.000869751f,  0.002014160f,  0.000122070f,
   -0.000061035f, -0.001296997f,  0.002883911f, -0.020690918f,
    0.009231567f, -0.140670776f, -0.088775635f, -0.913055420f,
  	1.031936646f,  0.221984863f,  0.151962280f,  0.012420654f,
    0.026840210f, -0.001266479f,  0.001907349f,  0.000106812f,
   -0.000061035f, -0.001388550f,  0.002700806f, -0.021789551f,
  	0.006134033f, -0.143676758f, -0.109161377f, -0.935195923f,
    1.014617920f,  0.198059082f,  0.151306152f,  0.008316040f,
  	0.025909424f, -0.001617432f,  0.001785278f,  0.000106812f,
   -0.000076294f, -0.001480103f,  0.002487183f, -0.022857666f,
  	0.002822876f, -0.146255493f, -0.130310059f, -0.956481934f,
  	0.996246338f,  0.174789429f,  0.150115967f,  0.004394531f,
    0.024932861f, -0.001937866f,  0.001693726f,  0.000091553f,
   -0.000076294f, -0.001586914f,  0.002227783f, -0.023910522f,
   -0.000686646f, -0.148422241f, -0.152206421f, -0.976852417f,
    0.976852417f,  0.152206421f,  0.148422241f,  0.000686646f,
  	0.023910522f, -0.002227783f,  0.001586914f,  0.000076294f,
   -0.000091553f, -0.001693726f,  0.001937866f, -0.024932861f,
   -0.004394531f, -0.150115967f, -0.174789429f, -0.996246338f,
    0.956481934f,  0.130310059f,  0.146255493f, -0.002822876f,
    0.022857666f, -0.002487183f,  0.001480103f,  0.000076294f,
   -0.000106812f, -0.001785278f,  0.001617432f, -0.025909424f,
   -0.008316040f, -0.151306152f, -0.198059082f, -1.014617920f,
    0.935195923f,  0.109161377f,  0.143676758f, -0.006134033f,
    0.021789551f, -0.002700806f,  0.001388550f,  0.000061035f,
   -0.000106812f, -0.001907349f,  0.001266479f, -0.026840210f,
   -0.012420654f, -0.151962280f, -0.221984863f, -1.031936646f,
  	0.913055420f,  0.088775635f,  0.140670776f, -0.009231567f,
  	0.020690918f, -0.002883911f,  0.001296997f,  0.000061035f,
   -0.000122070f, -0.002014160f,  0.000869751f, -0.027725220f,
   -0.016708374f, -0.152069092f, -0.246505737f, -1.048156738f,
    0.890090942f,  0.069168091f,  0.137298584f, -0.012115479f,
  	0.019577026f, -0.003051758f,  0.001205444f,  0.000045776f,
   -0.000137329f, -0.002120972f,  0.000442505f, -0.028533936f,
   -0.021179199f, -0.151596069f, -0.271591187f, -1.063217163f,
    0.866363525f,  0.050354004f,  0.133590698f, -0.014801025f,
    0.018463135f, -0.003173828f,  0.001113892f,  0.000045776f,
   -0.000152588f, -0.002243042f, -0.000030518f, -0.029281616f,
   -0.025817871f, -0.150497437f, -0.297210693f, -1.077117920f,
  	0.841949463f,  0.032379150f,  0.129562378f, -0.017257690f,
  	0.017349243f, -0.003280640f,  0.001037598f,  0.000030518f,
   -0.000167847f, -0.002349854f, -0.000549316f, -0.029937744f,
   -0.030609131f, -0.148773193f, -0.323318481f, -1.089782715f,
  	0.816864014f,  0.015228271f,  0.125259399f, -0.019531250f,
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}