33 lines
1.1 KiB
C
33 lines
1.1 KiB
C
/* SoX Resampler Library Copyright (c) 2007-12 robs@users.sourceforge.net
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* Licence for this file: LGPL v2.1 See LICENCE for details. */
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/* Resample using a non-interpolated poly-phase FIR with length LEN.*/
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/* Input must be followed by LEN-1 samples. */
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#define _ sum += (coef(p->shared->poly_fir_coefs, 0, FIR_LENGTH, rem, 0, j)) *at[j], ++j;
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static void FUNCTION(stage_t * p, fifo_t * output_fifo)
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{
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sample_t const * input = stage_read_p(p);
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int i, num_in = stage_occupancy(p), max_num_out = 1 + (int)(num_in*p->out_in_ratio);
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sample_t * output = fifo_reserve(output_fifo, max_num_out);
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for (i = 0; p->at.integer < num_in * p->L; ++i, p->at.integer += p->step.integer) {
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int div = p->at.integer / p->L, rem = p->at.integer % p->L;
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sample_t const * at = input + div;
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sample_t sum = 0;
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int j = 0;
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CONVOLVE
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output[i] = sum;
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}
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assert(max_num_out - i >= 0);
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fifo_trim_by(output_fifo, max_num_out - i);
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fifo_read(&p->fifo, p->at.integer / p->L, NULL);
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p->at.integer = p->at.integer % p->L;
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}
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#undef _
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#undef CONVOLVE
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#undef FIR_LENGTH
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#undef FUNCTION
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