Removed muffling cutoff from Hively Player blip buffer table, and threw in a generator
Chris Moeller
parent
7b38371ca7
commit
f0c3567214
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@ -238,42 +238,41 @@ int hvl_blip_read_samples( hvl_blip_t* m, int out [], int count, int gain )
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restrict
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*/
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/* Sinc_Generator( 0.9, 0.55, 4.5 ) */
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static short const bl_step [phase_count + 1] [half_width] =
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static int const bl_step [phase_count + 1] [half_width] =
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{
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{ 43, -115, 350, -488, 1136, -914, 5861,21022},
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{ 44, -118, 348, -473, 1076, -799, 5274,21001},
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{ 45, -121, 344, -454, 1011, -677, 4706,20936},
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{ 46, -122, 336, -431, 942, -549, 4156,20829},
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{ 47, -123, 327, -404, 868, -418, 3629,20679},
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{ 47, -122, 316, -375, 792, -285, 3124,20488},
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{ 47, -120, 303, -344, 714, -151, 2644,20256},
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{ 46, -117, 289, -310, 634, -17, 2188,19985},
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{ 46, -114, 273, -275, 553, 117, 1758,19675},
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{ 44, -108, 255, -237, 471, 247, 1356,19327},
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{ 43, -103, 237, -199, 390, 373, 981,18944},
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{ 42, -98, 218, -160, 310, 495, 633,18527},
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{ 40, -91, 198, -121, 231, 611, 314,18078},
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{ 38, -84, 178, -81, 153, 722, 22,17599},
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{ 36, -76, 157, -43, 80, 824, -241,17092},
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{ 34, -68, 135, -3, 8, 919, -476,16558},
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{ 32, -61, 115, 34, -60, 1006, -683,16001},
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{ 29, -52, 94, 70, -123, 1083, -862,15422},
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{ 27, -44, 73, 106, -184, 1152,-1015,14824},
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{ 25, -36, 53, 139, -239, 1211,-1142,14210},
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{ 22, -27, 34, 170, -290, 1261,-1244,13582},
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{ 20, -20, 16, 199, -335, 1301,-1322,12942},
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{ 18, -12, -3, 226, -375, 1331,-1376,12293},
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{ 15, -4, -19, 250, -410, 1351,-1408,11638},
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{ 13, 3, -35, 272, -439, 1361,-1419,10979},
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{ 11, 9, -49, 292, -464, 1362,-1410,10319},
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{ 9, 16, -63, 309, -483, 1354,-1383, 9660},
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{ 7, 22, -75, 322, -496, 1337,-1339, 9005},
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{ 6, 26, -85, 333, -504, 1312,-1280, 8355},
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{ 4, 31, -94, 341, -507, 1278,-1205, 7713},
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{ 3, 35, -102, 347, -506, 1238,-1119, 7082},
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{ 1, 40, -110, 350, -499, 1190,-1021, 6464},
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{ 0, 43, -115, 350, -488, 1136, -914, 5861}
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{ 0, 0, 0, 0, 0, 0, 0,32768},
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{ -1, 9, -30, 79, -178, 380, -923,32713},
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{ -2, 17, -58, 153, -346, 739,-1775,32549},
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{ -3, 24, -83, 221, -503, 1073,-2555,32277},
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{ -4, 30, -107, 284, -647, 1382,-3259,31898},
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{ -5, 36, -127, 340, -778, 1662,-3887,31415},
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{ -5, 40, -145, 390, -895, 1913,-4439,30832},
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{ -6, 44, -160, 433, -998, 2133,-4914,30151},
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{ -6, 47, -172, 469,-1085, 2322,-5313,29377},
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{ -6, 49, -181, 499,-1158, 2479,-5636,28515},
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{ -6, 50, -188, 521,-1215, 2604,-5885,27570},
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{ -5, 51, -193, 537,-1257, 2697,-6063,26548},
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{ -5, 51, -195, 547,-1285, 2760,-6172,25455},
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{ -5, 50, -195, 550,-1298, 2792,-6214,24298},
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{ -4, 49, -192, 548,-1298, 2795,-6193,23084},
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{ -4, 47, -188, 540,-1284, 2770,-6112,21820},
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{ -3, 45, -182, 526,-1258, 2719,-5976,20513},
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{ -3, 42, -175, 508,-1221, 2643,-5788,19172},
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{ -2, 39, -166, 486,-1173, 2544,-5554,17805},
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{ -2, 36, -156, 460,-1116, 2425,-5277,16418},
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{ -1, 33, -145, 431,-1050, 2287,-4963,15020},
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{ -1, 30, -133, 399, -977, 2132,-4615,13618},
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{ -1, 26, -120, 365, -898, 1963,-4240,12221},
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{ 0, 23, -107, 329, -813, 1783,-3843,10836},
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{ 0, 20, -94, 292, -725, 1593,-3427, 9470},
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{ 0, 17, -81, 254, -633, 1396,-2998, 8131},
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{ 0, 14, -68, 215, -540, 1194,-2560, 6824},
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{ 0, 11, -56, 177, -446, 989,-2119, 5556},
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{ 0, 8, -43, 139, -353, 784,-1678, 4334},
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{ 0, 6, -31, 102, -260, 581,-1242, 3162},
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{ 0, 3, -20, 66, -170, 381, -814, 2046},
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{ 0, 1, -9, 32, -83, 187, -399, 991},
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{ 0, 0, 0, 0, 0, 0, 0, 0}
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};
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/* Shifting by pre_shift allows calculation using unsigned int rather than
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@ -288,8 +287,8 @@ void hvl_blip_add_delta( hvl_blip_t* m, unsigned time, int delta )
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int const phase_shift = frac_bits - phase_bits;
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int phase = fixed >> phase_shift & (phase_count - 1);
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short const* in = bl_step [phase];
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short const* rev = bl_step [phase_count - phase];
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int const* in = bl_step [phase];
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int const* rev = bl_step [phase_count - phase];
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int interp = fixed >> (phase_shift - delta_bits) & (delta_unit - 1);
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int delta2 = (delta * interp) >> delta_bits;
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@ -0,0 +1,88 @@
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#include <stdio.h>
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#include <stdlib.h>
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#define _USE_MATH_DEFINES
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#include <math.h>
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#ifndef M_PI
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#define M_PI 3.141592653589793
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#endif
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enum { half_width = 8 };
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enum { phase_bits = 5 };
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enum { phase_count = 1 << phase_bits };
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enum { sinc_samples = phase_count * half_width };
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static float sinc_lut[sinc_samples + 1];
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static float window_lut[sinc_samples + 1];
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static int bl_step[phase_count + 1] [half_width];
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static int fEqual(const float b, const float a)
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{
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return fabs(a - b) < 1.0e-6;
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}
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static float sinc(float x)
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{
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return fEqual(x, 0.0) ? 1.0 : sin(x * M_PI) / (x * M_PI);
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}
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int main(void)
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{
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unsigned i;
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int k;
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double dx = (float)(half_width) / sinc_samples, x = 0.0;
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for (i = 0; i < sinc_samples + 1; ++i, x += dx)
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{
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float y = x / half_width;
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#if 0
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// Blackman
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float window = 0.42659 - 0.49656 * cos(M_PI + M_PI * y) + 0.076849 * cos(2.0 * M_PI * y);
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#elif 1
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// Nuttal 3 term
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float window = 0.40897 + 0.5 * cos(M_PI * y) + 0.09103 * cos(2.0 * M_PI * y);
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#elif 0
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// C.R.Helmrich's 2 term window
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float window = 0.79445 * cos(0.5 * M_PI * y) + 0.20555 * cos(1.5 * M_PI * y);
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#elif 0
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// Lanczos
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float window = sinc(y);
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#endif
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sinc_lut[i] = fabs(x) < half_width ? sinc(x) : 0.0;
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window_lut[i] = window;
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}
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for (i = 0; i <= phase_count / 2; ++i)
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{
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float kernel_sum = 0;
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float kernel[half_width * 2];
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for (k = half_width; k >= -half_width + 1; --k)
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{
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int pos = k * phase_count;
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int abs_pos = abs(i - pos);
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kernel_sum += kernel[k + half_width - 1] = sinc_lut[abs_pos] * window_lut[abs_pos];
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}
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kernel_sum = (1.0 / kernel_sum) * 32768.0;
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for (k = 0; k < half_width; ++k)
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bl_step[i][k] = (int)(kernel[k] * kernel_sum);
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for (k = 0; k < half_width; ++k)
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bl_step[phase_count - i][half_width - k - 1] = (int)(kernel[half_width + k] * kernel_sum);
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}
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printf( "static int const bl_step [phase_count + 1] [half_width] =\n{\n" );
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for (i = 0; i <= phase_count; ++i)
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{
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printf("{");
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for (k = 0; k < half_width; ++k)
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{
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printf("%5d", bl_step[i][k]);
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if (k < half_width - 1) printf(",");
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}
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printf("}"); if (i < phase_count) printf(",");
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printf("\n");
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}
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printf( "};\n" );
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return 0;
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}
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