test_quantize.py

#!/bin/python3

import sys

# 1 = quantize to beat
# 2 = quantize to half-beat
# 3 = quantize to third-beat
# 4 = quantize to quarter-beat

if len(sys.argv)>1:
    quantize_level = int(sys.argv[1])
else:
    quantize_level = 1

PPQN = 24
BARS_PER_PHRASE = 4
BEATS_PER_BAR = 4
LOOP_LENGTH = PPQN * BARS_PER_PHRASE * BEATS_PER_BAR

def is_bpm_on_multiplier(ticks, multiplier, offset = 0):
    p = PPQN*multiplier
    v = ticks==offset or ticks%p==offset
    return v

def find_nearest_quantized_time(time, quantization):
    print("time to quantize is %s at level %s " % (time, quantization), end='\t')

    ticks_per_quant_level = PPQN/quantization
    print("ticks_per_quant_level=%s" % ticks_per_quant_level, end='\t')
    #quantization = ticks_per_quant_level

    step_num = int(time / ticks_per_quant_level)
    step_start_at_tick = step_num * ticks_per_quant_level
    diff = time - step_start_at_tick

    print("step_num:\t%s\tstep_start_at_tick:\t%s\tdiff:\t%s" % (step_num, step_start_at_tick, diff), end='\t')

    if (diff < int(ticks_per_quant_level/2)):
        print ("diff is <  quantization/2 (%s)" % (ticks_per_quant_level/2), end='\t')
        step = step_start_at_tick
    else:
        print ("diff is >= quantization/2 (%s)" % (ticks_per_quant_level/2), end='\t')
        step = step_start_at_tick + ticks_per_quant_level
    
    quantized_time = step % LOOP_LENGTH

    print ("got result %s (beat number %s)" % (quantized_time, int(quantized_time/PPQN)))

    return quantized_time % LOOP_LENGTH


for x in range(0,LOOP_LENGTH):
    if (is_bpm_on_multiplier(x, 1)):
        print ("BEAT! number %s at tick %s" % (int(x/PPQN), x))
    find_nearest_quantized_time(x, quantize_level)