libcw/py/gen_wavetables/old/sample_looper.py
2024-09-05 11:17:08 -04:00

393 lines
10 KiB
Python

import math
import json
import array
import types
import matplotlib.pyplot as plt
import numpy as np
import wt_util
def plot_overlap( xV, bi, ei, wndN, smp_per_cycle, title ):
fig, ax = plt.subplots(1,1)
x0 = [ i for i in range(bi-wndN,bi+wndN) ]
x1 = [ x-x0[0] for x in x0 ]
ax.plot(x1,xV[x0])
x0 = [ i for i in range(ei-wndN,ei+wndN) ]
x1 = [ x-x0[0] for x in x0 ]
ax.plot(x1,xV[x0])
plt.title(title)
plt.show()
def sign(x):
return x<0
def find_zero_crossing( xV, si, inc ):
# find the next zero crossing before/after si
while si > 0:
if sign(xV[si-1])==False and sign(xV[si])==True:
break;
si += inc
return si
def meas_fit(xV,ei,bi,wndN):
if bi-wndN < 0 or ei+wndN > len(xV):
return None
v0 = xV[ei-wndN:ei+wndN]/0x7fffffff
v1 = xV[bi-wndN:bi+wndN]/0x7fffffff
dv = (v1-v0) * (v1-v0)
return np.mean(dv)
def find_loop_points_1( xV, bsi, esi, smp_per_cycle, wndN, est_N ):
# find the first zero crossing after the end of the search range
ei = find_zero_crossing(xV,esi,-1)
min_d = None
min_bi = None
bi = bsi
# make est_N guesses
for i in range(0,est_N):
# find the next zero crossing after bi
bi = find_zero_crossing(xV,bi,1)
# measure the quality of the fit with the end of the loop
d = meas_fit(xV,ei,bi,wndN)
#print(i,bi,d)
# store the best loop begin point
if min_bi is None or d < min_d:
min_d = d
min_bi = bi
# advance
bi += int(wndN) #smp_per_cycle
return min_bi, ei, min_d
def find_loop_points_2(xV,bsi,esi, smp_per_cycle, wndN, est_N ):
def _track_min( min_i, min_d, i, d ):
if min_i is None or d<min_d:
return i,d
return min_i,min_d
spc_2 = int(smp_per_cycle/2)
bzi,ezi = esi-spc_2, esi+spc_2
max_i = int(np.argmax(xV[bzi:ezi]) + bzi)
ei = find_zero_crossing(xV,max_i,1)
bi = max_i - int(round(((esi-bsi)/smp_per_cycle) * smp_per_cycle))
bi_p = bi
bi_n = bi-1
min_bi = None
min_d = None
for i in range(est_N):
# evaluate the fit of the next zero-crossing relative to bi_p
bi_p = find_zero_crossing(xV,bi_p,1)
if bi_p < ei:
d_p = meas_fit(xV,ei,bi_p,wndN)
min_bi,min_d = _track_min(min_bi,min_d,bi_p,d_p)
bi_p += 1 # advance bi_p forward
# evaluate the fit of the previous zero-crozzing relative to bi_n
bi_n = find_zero_crossing(xV,bi_n,-1)
d_n = meas_fit(xV,ei,bi_n,wndN)
min_bi,min_d = _track_min(min_bi,min_d,bi_n,d_n)
bi_n -= 1 # advance bi_n backward
return min_bi, ei, min_d
def find_loop_points_3(xV,bsi,esi, smp_per_cycle, wndN, est_N ):
spc_2 = int(smp_per_cycle/2)
bzi,ezi = bsi-spc_2, bsi+spc_2
max_i = int(np.argmax(xV[bzi:ezi]) + bzi)
bi = find_zero_crossing(xV,max_i,1)
ei = bi + math.ceil(smp_per_cycle)
#print(bi,ei,ei-bi,smp_per_cycle)
d = meas_fit(xV,ei,bi,wndN)
return bi,ei,d
def find_loop_points_4(xV,bsi,esi, smp_per_cycle, wndN, est_N ):
def _track_min( min_i, min_d, i, d ):
if d is not None and (min_i is None or d<min_d):
return i,d
return min_i,min_d
min_i = None
min_d = None
spc_2 = int(smp_per_cycle/2)
for i in range(est_N):
bzi,ezi = bsi-spc_2, bsi+spc_2
max_i = int(np.argmax(xV[bzi:ezi]) + bzi)
bi = find_zero_crossing(xV,max_i,1)
ei = bi + math.ceil(smp_per_cycle)
#print(bi,ei,ei-bi,smp_per_cycle)
d = meas_fit(xV,ei,bi,wndN)
min_i,min_d = _track_min(min_i,min_d,bi,d)
bsi += math.ceil(smp_per_cycle)
return min_i,min_i + math.ceil(smp_per_cycle),min_d
def find_loop_points(xV,bsi,esi, smp_per_cycle, wndN, est_N ):
def _track_min( min_i, min_d, i, d ):
if d is not None and (min_i is None or d<min_d):
return i,d
return min_i,min_d
min_i = None
min_d = None
spc_2 = int(smp_per_cycle/2)
bzi,ezi = bsi-spc_2, bsi+spc_2
max_i = int(np.argmax(xV[bzi:ezi]) + bzi)
bi = find_zero_crossing(xV,max_i,1)
for i in range(est_N):
ei = math.ceil(bi + (i+1)*smp_per_cycle)
#print(bi,ei,ei-bi,smp_per_cycle)
d = meas_fit(xV,ei,bi,wndN)
min_i,min_d = _track_min(min_i,min_d,ei,d)
return bi,min_i,min_d
def find_best_zero_crossing(xV,bi,ei,wndN):
bi0 = find_zero_crossing(xV,bi-1,-1)
bi1 = find_zero_crossing(xV,bi,1)
ei0 = find_zero_crossing(xV,ei-1,-1)
ei1 = find_zero_crossing(xV,ei,1)
beV = [ (ei0,bi0), (ei0,bi1), (ei1,bi0), (ei1,bi1) ]
i_min = None
d_min = None
for i,(ei,bi) in enumerate(beV):
d = meas_fit(xV,ei,bi,wndN)
if i_min is None or d < d_min:
i_min = i
d_min = d
ei,bi = beV[i_min]
return bi,ei,d_min
def determine_track_order( smpM, bli, eli ):
i_max = None
rms_max = None
rmsV = []
assert( smpM.shape[1] == 2 )
for i in range(smpM.shape[1]):
rms = np.mean(np.pow(smpM[bli:eli,i],2.0))
if i_max is None or rms > rms_max:
i_max = i
rms_max = rms
rmsV.append(float(rms))
return [ i_max, 0 if i_max==1 else 1 ]
def process_all_samples( markL, smpM, srate, args ):
wtL = []
#fund_hz = 13.75 * math.pow(2,(-9.0/12.0)) * math.pow(2.0,(args.midi_pitch / 12.0))
fund_hz = midi_pitch_to_hz(args.midi_pitch)
smp_per_cycle = int(srate / fund_hz)
end_offs_smp_idx = max(smp_per_cycle,int(args.end_offset_ms * srate / 1000))
loop_dur_smp = int(args.loop_dur_ms * srate / 1000)
wndN = int(smp_per_cycle/6)
print(f"Hz:{fund_hz} smp/cycle:{smp_per_cycle} loop_dur:{loop_dur_smp} cycles/loop:{loop_dur_smp/smp_per_cycle} wndN:{wndN}")
# for each sampled note
for beg_sec,end_sec,vel_label in markL:
beg_smp_idx = int(beg_sec * srate)
end_smp_idx = int(end_sec * srate)
r = {
"instr":"piano",
"pitch":args.midi_pitch,
"vel": int(vel_label),
"beg_smp_idx":beg_smp_idx,
"end_smp_idx":None,
"chL": []
}
# determine the loop search range from the end of the note sample
eli = end_smp_idx - end_offs_smp_idx
bli = eli - loop_dur_smp
ch_map = determine_track_order( smpM, beg_smp_idx, end_smp_idx)
#print(ch_map)
esi = beg_smp_idx;
for i in range(0,smpM.shape[1]):
ch_idx = ch_map[i]
xV = smpM[:,ch_idx]
if True:
#if i == 0:
# s_per_c = srate / fund_hz
# bi,ei,cost = find_loop_points(xV,bli,eli,s_per_c,wndN,args.guess_cnt)
s_per_c = srate / fund_hz
bi,ei,cost = find_loop_points_4(xV,bli,eli,s_per_c,wndN,args.guess_cnt)
if False:
bi,ei,cost = find_loop_points_2(xV,bli,eli,smp_per_cycle,wndN,args.guess_cnt)
if False:
if i == 0:
bi,ei,cost = find_loop_points(xV,bli,eli,smp_per_cycle,wndN,args.guess_cnt)
else:
bi,ei,cost = find_best_zero_crossing(xV,bi,ei,wndN)
if False:
if i == 0:
bi,ei,cost = find_loop_points(xV,bli,eli,smp_per_cycle,wndN,args.guess_cnt)
else:
pass
#print(i,bi,ei)
eli = ei # attempt to make the eli the second channel close to the first
loop_dur_sec = (ei-bi)/srate
cyc_per_loop = int(round((ei-bi)/smp_per_cycle))
plot_title = f"vel:{vel_label} cyc/loop:{cyc_per_loop} dur:{loop_dur_sec*1000:.1f} ms {ei-bi} smp ch:{ch_idx} cost:{0 if cost<= 0 else math.log(cost):.2f}"
plot_overlap(xV,bi,ei,wndN,smp_per_cycle,plot_title)
r["chL"].append({
"ch_idx":ch_idx,
"segL":[] })
r["chL"][-1]["segL"].append({
"cost":0,
"cyc_per_loop":1,
"bsi":beg_smp_idx,
"esi":bi })
r["chL"][-1]["segL"].append({
"cost":cost,
"cyc_per_loop":cyc_per_loop,
"bsi":bi,
"esi":ei })
esi = max(esi,ei)
r['end_smp_idx'] = esi
r["chL"] = sorted(r["chL"],key=lambda x: x["ch_idx"])
wtL.append(r)
return wtL
def write_loop_label_file( fname, wtL, srate ):
with open(fname,"w") as f:
for r in wtL:
for cr in r['chL']:
for sr in cr['segL']:
beg_sec = sr['bsi'] / srate
end_sec = sr['esi'] / srate
if sr['cost']!=0:
cost = math.log(sr['cost'])
label = f"ch:{cr['ch_idx']} {r['vel']} {cost:.2f}"
f.write(f"{beg_sec}\t{end_sec}\t{label}\n")
def write_wt_file( fname, audio_fname, wtL, srate ):
r = {
"audio_fname":audio_fname,
#"srate":srate,
"wt":wtL
}
with open(fname,"w") as f:
json.dump(r,f);
def gen_loop_positions( audio_fname, marker_tsv_fname, pitch, argsD, loop_marker_fname, wt_fname ):
args = types.SimpleNamespace(**argsD)
markL = wt_util.parse_marker_file(marker_tsv_fname)
smpM,srate = wt_util.parse_audio_file(audio_fname)
chN = smpM.shape[1]
wtL = process_all_samples(markL,smpM,srate,args)
write_loop_label_file(loop_marker_fname, wtL, srate)
write_wt_file(wt_fname,audio_fname, wtL,srate)
if __name__ == "__main__":
audio_fname = "/home/kevin/temp/wt/wav/60_samples.wav"
marker_tsv_fname = "/home/kevin/temp/wt/60_marker.txt"
loop_marker_fname = "/home/kevin/temp/wt/60_loop_mark.txt"
wt_fname = "/home/kevin/temp/wt/bank/60_wt.json"
midi_pitch = 60
argsD = {
'end_offset_ms':100,
'loop_dur_ms':100,
'midi_pitch':midi_pitch,
'guess_cnt':40
}
gen_loop_positions( audio_fname, marker_tsv_fname, midi_pitch, argsD, loop_marker_fname, wt_fname )