de.sciss.jump3r.mp3

Class QuantizePVT

java.lang.Object

de.sciss.jump3r.mp3.QuantizePVT

public class QuantizePVT
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field and Description
float[]	adj43
float[]	ipow20
static int	IXMAX_VAL ix always <= 8191+15.
static int	LARGE_BITS
int[][][]	nr_of_sfb_block The following table is used to implement the scalefactor partitioning for MPEG2 as described in section 2.4.3.2 of the IS.
float[]	pow20
float[]	pow43
int[]	pretab Table B.6: layer3 preemphasis
static int	Q_MAX2 minimum possible number of -cod_info.global_gain + ((scalefac[] + (cod_info.preflag ? pretab[sfb] : 0)) << (cod_info.scalefac_scale + 1)) + cod_info.subblock_gain[cod_info.window[sfb]] * 8; for long block, 0+((15+3)<<2) = 18*4 = 72 for short block, 0+(15<<2)+7*8 = 15*4+56 = 116
ScaleFac[]	sfBandIndex Here are MPEG1 Table B.8 and MPEG2 Table B.1 -- Layer III scalefactor bands.

Constructor Summary

Constructors

Constructor and Description
QuantizePVT()

Method Summary

Modifier and Type	Method and Description
float	athAdjust(float a, float x, float athFloor) Robert Hegemann 2001-04-27: this adjusts the ATH, keeping the original noise floor affects the higher frequencies more than the lower ones
int	calc_noise(GrInfo cod_info, float[] l3_xmin, float[] distort, CalcNoiseResult res, CalcNoiseData prev_noise) -oo dB => -1.00 - 6 dB => -0.97 - 3 dB => -0.80 - 2 dB => -0.64 - 1 dB => -0.38 0 dB => 0.00 + 1 dB => +0.49 + 2 dB => +1.06 + 3 dB => +1.68 + 6 dB => +3.69 +10 dB => +6.45
int	calc_xmin(LameGlobalFlags gfp, III_psy_ratio ratio, GrInfo cod_info, float[] pxmin) Calculate the allowed distortion for each scalefactor band, as determined by the psychoacoustic model.
float	IPOW20(int x)
void	iteration_init(LameGlobalFlags gfp) initialization for iteration_loop
int	on_pe(LameGlobalFlags gfp, float[][] pe, int[] targ_bits, int mean_bits, int gr, int cbr) allocate bits among 2 channels based on PE mt 6/99 bugfixes rh 8/01: often allocated more than the allowed 4095 bits
float	POW20(int x)
void	reduce_side(int[] targ_bits, float ms_ener_ratio, int mean_bits, int max_bits)
void	set_frame_pinfo(LameGlobalFlags gfp, III_psy_ratio[][] ratio) updates plotting data for a whole frame Robert Hegemann 2000-10-21
void	setModules(Takehiro tk, Reservoir rv, PsyModel psy)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

IXMAX_VAL

public static final int IXMAX_VAL

ix always <= 8191+15. see count_bits()

See Also:

Constant Field Values

Q_MAX2

public static final int Q_MAX2

minimum possible number of -cod_info.global_gain + ((scalefac[] + (cod_info.preflag ? pretab[sfb] : 0)) << (cod_info.scalefac_scale + 1)) + cod_info.subblock_gain[cod_info.window[sfb]] * 8; for long block, 0+((15+3)<<2) = 18*4 = 72 for short block, 0+(15<<2)+7*8 = 15*4+56 = 116

See Also:

Constant Field Values

LARGE_BITS

public static final int LARGE_BITS

See Also:

Constant Field Values

nr_of_sfb_block

public final int[][][] nr_of_sfb_block

The following table is used to implement the scalefactor partitioning for MPEG2 as described in section 2.4.3.2 of the IS. The indexing corresponds to the way the tables are presented in the IS: [table_number][row_in_table][column of nr_of_sfb]

pretab

public final int[] pretab

Table B.6: layer3 preemphasis

sfBandIndex

public final ScaleFac[] sfBandIndex

Here are MPEG1 Table B.8 and MPEG2 Table B.1 -- Layer III scalefactor bands.
Index into this using a method such as:
idx = fr_ps.header.sampling_frequency + (fr_ps.header.version * 3)

pow20

public float[] pow20

ipow20

public float[] ipow20

pow43

public float[] pow43

adj43

public float[] adj43

Constructor Detail

QuantizePVT

public QuantizePVT()

Method Detail

setModules

public final void setModules(Takehiro tk,
                             Reservoir rv,
                             PsyModel psy)

POW20

public final float POW20(int x)

IPOW20

public final float IPOW20(int x)

iteration_init

public final void iteration_init(LameGlobalFlags gfp)

initialization for iteration_loop

on_pe

public final int on_pe(LameGlobalFlags gfp,
                       float[][] pe,
                       int[] targ_bits,
                       int mean_bits,
                       int gr,
                       int cbr)

allocate bits among 2 channels based on PE
mt 6/99
bugfixes rh 8/01: often allocated more than the allowed 4095 bits

reduce_side

public final void reduce_side(int[] targ_bits,
                              float ms_ener_ratio,
                              int mean_bits,
                              int max_bits)

athAdjust

public final float athAdjust(float a,
                             float x,
                             float athFloor)

Robert Hegemann 2001-04-27: this adjusts the ATH, keeping the original noise floor affects the higher frequencies more than the lower ones

calc_xmin

public final int calc_xmin(LameGlobalFlags gfp,
                           III_psy_ratio ratio,
                           GrInfo cod_info,
                           float[] pxmin)

Calculate the allowed distortion for each scalefactor band, as determined by the psychoacoustic model. xmin(sb) = ratio(sb) * en(sb) / bw(sb) returns number of sfb's with energy > ATH

calc_noise

public final int calc_noise(GrInfo cod_info,
                            float[] l3_xmin,
                            float[] distort,
                            CalcNoiseResult res,
                            CalcNoiseData prev_noise)

 -oo dB  =>  -1.00
 - 6 dB  =>  -0.97
 - 3 dB  =>  -0.80
 - 2 dB  =>  -0.64
 - 1 dB  =>  -0.38
   0 dB  =>   0.00
 + 1 dB  =>  +0.49
 + 2 dB  =>  +1.06
 + 3 dB  =>  +1.68
 + 6 dB  =>  +3.69
 +10 dB  =>  +6.45
 

set_frame_pinfo

public final void set_frame_pinfo(LameGlobalFlags gfp,
                                  III_psy_ratio[][] ratio)

updates plotting data for a whole frame Robert Hegemann 2000-10-21