Path: blob/master/libs/fluidsynth/src/utils/fluid_conv_tables.h
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1#ifndef _FLUID_CONV_TABLES_H2#define _FLUID_CONV_TABLES_H34/*5Attenuation range in centibels.6Attenuation range is the dynamic range of the volume envelope generator7from 0 to the end of attack segment.8fluidsynth is a 24 bit synth, it could (should??) be 144 dB of attenuation.9However the spec makes no distinction between 16 or 24 bit synths, so use1096 dB here.1112Note about usefulness of 24 bits:131)Even fluidsynth is a 24 bit synth, this format is only relevant if14the sample format coming from the soundfont is 24 bits and the audio sample format15chosen by the application (audio.sample.format) is not 16 bits.16172)When the sample soundfont is 16 bits, the internal 24 bits number have1816 bits msb and lsb to 0. Consequently, at the DAC output, the dynamic range of19this 24 bit sample is reduced to the the dynamic of a 16 bits sample (ie 90 db)20even if this sample is produced by the audio driver using an audio sample format21compatible for a 24 bit DAC.22233)When the audio sample format settings is 16 bits (audio.sample.format), the24audio driver will make use of a 16 bit DAC, and the dynamic will be reduced to 96 dB25even if the initial sample comes from a 24 bits soundfont.2627In both cases (2) or (3), the real dynamic range is only 96 dB.2829Other consideration for FLUID_NOISE_FLOOR related to case (1),(2,3):30- for case (1), FLUID_NOISE_FLOOR should be the noise floor for 24 bits (i.e -138 dB).31- for case (2) or (3), FLUID_NOISE_FLOOR should be the noise floor for 16 bits (i.e -90 dB).32*/33#define FLUID_PEAK_ATTENUATION 960.0f3435#define FLUID_CENTS_HZ_SIZE 120036#define FLUID_VEL_CB_SIZE 12837#define FLUID_CB_AMP_SIZE 144138#define FLUID_PAN_SIZE 10023940#endif414243