def merge_codebook(codebook, nGoal, freqs=[]):
"""
merge the codebook in an iterative and greedy way.
Algo:
- finds closest pair of codes
- merge them, using freqs if available
- repeat until desired number of codes (nGoal)
Returns smaller codebook, #codes=nGoal
Also returns frequencies of the new codebook
Code not optimized!!!!!! close to n^3 operations
"""
import numpy as np
import VQutils as VQU
import copy
# set freqs, sanity checks
if freqs == []:
freqs = np.ones(codebook.shape[0])
freqs = np.array(freqs)
assert (freqs.size == codebook.shape[0])
assert (nGoal < codebook.shape[0])
assert (nGoal > 0)
# let's go!
cb = copy.deepcopy(codebook)
for k in range(codebook.shape[0] - nGoal):
# compute dists for all pairs
dists = np.zeros([cb.shape[0], cb.shape[0]])
for l in range(dists.shape[0]):
dists[l, l] = np.inf
for c in range(l + 1, dists.shape[1]):
dists[l, c] = VQU.euclidean_dist(cb[l], cb[c])
dists[c, l] = np.inf
# find closest pair
pos = np.where(dists == dists.min())
code1 = pos[0][0]
code2 = pos[1][0]
print 'iter', k, ' min distance=', dists.min(
), ' codes=', code1, ',', code2
assert (code1 < code2
) #code1 should be smaller from how we filled dists
# merge
#cb[code1,:] = np.mean([cb[code1,:]*freqs[code1],cb[code2,:]*freqs[code2]],axis=0) * 1. / (freqs[code1] + freqs[code2])
cb[code1, :] = np.mean([cb[code1, :], cb[code2, :]], axis=0)
freqs[code1] += freqs[code2]
# remove
if code2 + 1 < cb.shape[0]:
cb[code2, :] = cb[-1, :]
freqs[code2] = freqs[-1]
cb = cb[:-1]
freqs = freqs[:-1]
# done
return cb, freqs
def merge_codebook(codebook,nGoal,freqs = []):
"""
merge the codebook in an iterative and greedy way.
Algo:
- finds closest pair of codes
- merge them, using freqs if available
- repeat until desired number of codes (nGoal)
Returns smaller codebook, #codes=nGoal
Also returns frequencies of the new codebook
Code not optimized!!!!!! close to n^3 operations
"""
import numpy as np
import VQutils as VQU
import copy
# set freqs, sanity checks
if freqs == []:
freqs = np.ones(codebook.shape[0])
freqs = np.array(freqs)
assert(freqs.size == codebook.shape[0])
assert(nGoal < codebook.shape[0])
assert(nGoal > 0)
# let's go!
cb = copy.deepcopy(codebook)
for k in range(codebook.shape[0] - nGoal):
# compute dists for all pairs
dists = np.zeros([cb.shape[0],cb.shape[0]])
for l in range(dists.shape[0]):
dists[l,l] = np.inf
for c in range(l+1,dists.shape[1]):
dists[l,c] = VQU.euclidean_dist(cb[l],cb[c])
dists[c,l] = np.inf
# find closest pair
pos = np.where(dists==dists.min())
code1 = pos[0][0]
code2 = pos[1][0]
print 'iter',k,' min distance=',dists.min(),' codes=',code1,',',code2
assert(code1 < code2)#code1 should be smaller from how we filled dists
# merge
#cb[code1,:] = np.mean([cb[code1,:]*freqs[code1],cb[code2,:]*freqs[code2]],axis=0) * 1. / (freqs[code1] + freqs[code2])
cb[code1,:] = np.mean([cb[code1,:],cb[code2,:]],axis=0)
freqs[code1] += freqs[code2]
# remove
if code2 + 1 < cb.shape[0]:
cb[code2,:] = cb[-1,:]
freqs[code2] = freqs[-1]
cb = cb[:-1]
freqs = freqs[:-1]
# done
return cb, freqs
def LLE_my_codebook(codebook, nNeighbors=5, nRand=5):
"""
Performs LLE on the codebook
Display the result
LLE code not mine, see code for reference.
nRand=number of random images added
"""
import pylab as P
import LLE
import numpy as np
import VQutils as VQU
# compute LLE, goal is 2D
LLEres = LLE.LLE(codebook.T, nNeighbors, 2)
# plot that result
P.plot(LLEres[0, :], LLEres[1, :], '.')
P.hold(True)
# prepare to plot
patch_size = codebook[0, :].size / 12
# add random
for k in range(nRand):
idx = np.random.randint(LLEres.shape[1])
add_image(P, codebook[idx, :].reshape(12, patch_size), LLEres[0, idx],
LLEres[1, idx], .08)
# plot extreme left codebook
idx = np.argmin(LLEres[0, :])
add_image(P, codebook[idx, :].reshape(12, patch_size), LLEres[0, idx],
LLEres[1, idx])
# plot extreme right codebook
idx = np.argmax(LLEres[0, :])
add_image(P, codebook[idx, :].reshape(12, patch_size), LLEres[0, idx],
LLEres[1, idx])
# plot extreme up codebook
idx = np.argmax(LLEres[1, :])
add_image(P, codebook[idx, :].reshape(12, patch_size), LLEres[0, idx],
LLEres[1, idx])
# plot extreme down codebook
idx = np.argmin(LLEres[1, :])
add_image(P, codebook[idx, :].reshape(12, patch_size), LLEres[0, idx],
LLEres[1, idx])
# plot middle codebook
idx = np.argmin([VQU.euclidean_dist(r, np.zeros(2)) for r in LLEres.T])
add_image(P, codebook[idx, :].reshape(12, patch_size), LLEres[0, idx],
LLEres[1, idx])
# done, release, show
P.hold(False)
P.show()
def LLE_my_codebook(codebook,nNeighbors=5,nRand=5):
"""
Performs LLE on the codebook
Display the result
LLE code not mine, see code for reference.
nRand=number of random images added
"""
import pylab as P
import LLE
import numpy as np
import VQutils as VQU
# compute LLE, goal is 2D
LLEres = LLE.LLE(codebook.T,nNeighbors,2)
# plot that result
P.plot(LLEres[0,:],LLEres[1,:],'.')
P.hold(True)
# prepare to plot
patch_size = codebook[0,:].size / 12
# add random
for k in range(nRand):
idx = np.random.randint(LLEres.shape[1])
add_image(P,codebook[idx,:].reshape(12,patch_size),LLEres[0,idx],LLEres[1,idx],.08)
# plot extreme left codebook
idx = np.argmin(LLEres[0,:])
add_image(P,codebook[idx,:].reshape(12,patch_size),LLEres[0,idx],LLEres[1,idx])
# plot extreme right codebook
idx = np.argmax(LLEres[0,:])
add_image(P,codebook[idx,:].reshape(12,patch_size),LLEres[0,idx],LLEres[1,idx])
# plot extreme up codebook
idx = np.argmax(LLEres[1,:])
add_image(P,codebook[idx,:].reshape(12,patch_size),LLEres[0,idx],LLEres[1,idx])
# plot extreme down codebook
idx = np.argmin(LLEres[1,:])
add_image(P,codebook[idx,:].reshape(12,patch_size),LLEres[0,idx],LLEres[1,idx])
# plot middle codebook
idx = np.argmin([VQU.euclidean_dist(r,np.zeros(2)) for r in LLEres.T])
add_image(P,codebook[idx,:].reshape(12,patch_size),LLEres[0,idx],LLEres[1,idx])
# done, release, show
P.hold(False)
P.show()
def knn_from_freqs_on_artists(filenames,
codebook,
pSize=8,
keyInv=True,
downBeatInv=False,
bars=2,
normalize=True,
confMatrix=True,
use_l0_dist=False,
use_artists=False):
"""
Performs a leave-one-out experiments where we try to guess the artist
from it's nearest neighbors in frequencies
We use squared euclidean distance.
filenames are expected to be: */artist/album/*.mat
if confMatrix=True, plot it.
if use_artists, song are matched to artist, not other songs
RETURNS:
- confusion matrix
- freqs per file
- artist per file
"""
import numpy as np
import os
import VQutils as VQU
import time
import copy
nCodes = codebook.shape[0]
# get frequencies for all songs
tstart = time.time()
freqs = freqs_my_songs(filenames,
codebook,
pSize=pSize,
keyInv=keyInv,
downBeatInv=downBeatInv,
bars=bars,
normalize=normalize)
print 'all frequencies computed in', (time.time() - tstart), 'seconds.'
# get artists for all songs
artists = []
for f in filenames:
tmp, song = os.path.split(f)
tmp, album = os.path.split(tmp)
tmp, artist = os.path.split(tmp)
artists.append(artist)
artists = np.array(artists)
# names of artists
artist_names = np.unique(np.sort(artists))
nArtists = artist_names.shape[0]
# sanity check
assert (len(filenames) == len(artists))
# compute distance between all songs
nFiles = len(filenames)
tstart = time.time()
if not use_artists:
dists = np.zeros([nFiles, nFiles])
for l in range(nFiles):
for c in range(l + 1, nFiles):
if len(freqs[l]) == 0 or len(freqs[c]) == 0:
dists[l, c] = np.inf
dists[c, l] = np.inf
continue
if use_l0_dist:
dists[l, c] = l0_dist(freqs[l], freqs[c])
else:
dists[l, c] = VQU.euclidean_dist(freqs[l], freqs[c])
dists[c, l] = dists[l, c]
for l in range(nFiles): # fill diag with inf
dists[l, l] = np.inf
else:
# create a matrix songs * nArtists
dists = np.zeros([nFiles, nArtists])
# precompute cntArtists and artistFreqs, not normalized
cntArtists = {}
artistFreqs = {}
for k in artist_names:
cntArtists[k] = 0
artistFreqs[k] = np.zeros([1, nCodes])
for k in range(artists.shape[0]):
art = artists[k]
cntArtists[art] += 1
artistFreqs[art] += freqs[k]
# iterate over files
for l in range(nFiles):
currArtist = artists[l]
currCntArtists = copy.deepcopy(cntArtists)
currCntArtists[currArtist] -= 1
currArtistFreqs = copy.deepcopy(artistFreqs)
currArtistFreqs[currArtist] -= freqs[l]
for k in currArtistFreqs.keys(): # normalize
currArtistFreqs[k] *= 1. / currCntArtists[k]
# fill in the line in dists
for c in range(nArtists):
art = artist_names[c]
if use_l0_dist:
dists[l, c] = l0_dist(freqs[l], currArtistFreqs[art])
else:
dists[l, c] = VQU.euclidean_dist(freqs[l],
currArtistFreqs[art])
print 'distances computed in', (time.time() - tstart), 'seconds.'
# confusion matrix
confMat = np.zeros([nArtists, nArtists])
# performs leave-one-out KNN
nExps = 0
nGood = 0
randScore = 0 # sums prob of having it right by luck, must divide by nExps
for songid in range(nFiles):
if len(freqs[songid]) == 0:
continue
# get close matches ordered, remove inf
orderedMatches = np.argsort(dists[songid, :])
orderedMatches[np.where(dists[1, orderedMatches] != np.inf)]
# artist
artist = artists[songid]
nMatches = orderedMatches.shape[0]
if use_artists:
assert nMatches == nArtists
# get stats
nExps += 1
if not use_artists:
nGoodMatches = np.where(
artists[orderedMatches] == artist)[0].shape[0]
if nGoodMatches == 0:
continue
randScore += nGoodMatches * 1. / nMatches
pred_artist = artists[orderedMatches[0]]
else:
randScore += 1. / nArtists
pred_artist = artist_names[orderedMatches[0]]
if pred_artist == artist:
nGood += 1
# fill confusion matrix
real_artist_id = np.where(artist_names == artist)[0][0]
pred_artist_id = np.where(artist_names == pred_artist)[0][0]
print songid, ') real artist:', artist, 'id=', real_artist_id, ', pred artist:', pred_artist, 'id=', pred_artist_id
confMat[real_artist_id, pred_artist_id] += 1
# done, print out
print 'nExps:', nExps
print 'rand accuracy:', (randScore * 1. / nExps)
print 'accuracy:', (nGood * 1. / nExps)
# plot confusion matrix
if confMatrix:
short_names = np.array([x[:2] for x in artist_names])
import pylab as P
P.imshow(confMat,
interpolation='nearest',
cmap=P.cm.gray_r,
origin='lower')
P.yticks(P.arange(artist_names.shape[0]), list(artist_names))
P.xticks(P.arange(artist_names.shape[0]), list(short_names))
P.title('confusion matrix (real/predicted)')
P.ylabel('TRUE')
P.xlabel('RECOG')
P.colorbar()
# return confusion matrix
return confMat, freqs, artists
def knn_from_freqs_on_artists(filenames,codebook,pSize=8,keyInv=True,
downBeatInv=False,bars=2,normalize=True,
confMatrix=True,use_l0_dist=False,use_artists=False):
"""
Performs a leave-one-out experiments where we try to guess the artist
from it's nearest neighbors in frequencies
We use squared euclidean distance.
filenames are expected to be: */artist/album/*.mat
if confMatrix=True, plot it.
if use_artists, song are matched to artist, not other songs
RETURNS:
- confusion matrix
- freqs per file
- artist per file
"""
import numpy as np
import os
import VQutils as VQU
import time
import copy
nCodes = codebook.shape[0]
# get frequencies for all songs
tstart = time.time()
freqs = freqs_my_songs(filenames,codebook,pSize=pSize,keyInv=keyInv,
downBeatInv=downBeatInv,bars=bars,
normalize=normalize)
print 'all frequencies computed in',(time.time()-tstart),'seconds.'
# get artists for all songs
artists = []
for f in filenames:
tmp, song = os.path.split(f)
tmp,album = os.path.split(tmp)
tmp,artist = os.path.split(tmp)
artists.append(artist)
artists = np.array(artists)
# names of artists
artist_names = np.unique(np.sort(artists))
nArtists = artist_names.shape[0]
# sanity check
assert(len(filenames)==len(artists))
# compute distance between all songs
nFiles = len(filenames)
tstart = time.time()
if not use_artists:
dists = np.zeros([nFiles,nFiles])
for l in range(nFiles):
for c in range(l+1,nFiles):
if len(freqs[l])==0 or len(freqs[c])==0:
dists[l,c] = np.inf
dists[c,l] = np.inf
continue
if use_l0_dist:
dists[l,c] = l0_dist(freqs[l],freqs[c])
else:
dists[l,c] = VQU.euclidean_dist(freqs[l],freqs[c])
dists[c,l] = dists[l,c]
for l in range(nFiles): # fill diag with inf
dists[l,l] = np.inf
else:
# create a matrix songs * nArtists
dists = np.zeros([nFiles,nArtists])
# precompute cntArtists and artistFreqs, not normalized
cntArtists = {}
artistFreqs = {}
for k in artist_names:
cntArtists[k] = 0
artistFreqs[k] = np.zeros([1,nCodes])
for k in range(artists.shape[0]):
art = artists[k]
cntArtists[art] += 1
artistFreqs[art] += freqs[k]
# iterate over files
for l in range(nFiles):
currArtist = artists[l]
currCntArtists = copy.deepcopy(cntArtists)
currCntArtists[currArtist] -= 1
currArtistFreqs = copy.deepcopy(artistFreqs)
currArtistFreqs[currArtist] -= freqs[l]
for k in currArtistFreqs.keys(): # normalize
currArtistFreqs[k] *= 1. / currCntArtists[k]
# fill in the line in dists
for c in range(nArtists):
art = artist_names[c]
if use_l0_dist:
dists[l,c] = l0_dist(freqs[l],currArtistFreqs[art])
else:
dists[l,c] = VQU.euclidean_dist(freqs[l],currArtistFreqs[art])
print 'distances computed in',(time.time()-tstart),'seconds.'
# confusion matrix
confMat = np.zeros([nArtists,nArtists])
# performs leave-one-out KNN
nExps = 0
nGood = 0
randScore = 0 # sums prob of having it right by luck, must divide by nExps
for songid in range(nFiles):
if len(freqs[songid]) == 0:
continue
# get close matches ordered, remove inf
orderedMatches = np.argsort(dists[songid,:])
orderedMatches[np.where(dists[1,orderedMatches] != np.inf)]
# artist
artist = artists[songid]
nMatches = orderedMatches.shape[0]
if use_artists:
assert nMatches == nArtists
# get stats
nExps += 1
if not use_artists:
nGoodMatches = np.where(artists[orderedMatches]==artist)[0].shape[0]
if nGoodMatches == 0:
continue
randScore += nGoodMatches * 1. / nMatches
pred_artist = artists[orderedMatches[0]]
else:
randScore += 1. / nArtists
pred_artist = artist_names[orderedMatches[0]]
if pred_artist == artist:
nGood += 1
# fill confusion matrix
real_artist_id =np.where(artist_names==artist)[0][0]
pred_artist_id =np.where(artist_names==pred_artist)[0][0]
print songid,') real artist:',artist,'id=',real_artist_id,', pred artist:',pred_artist,'id=',pred_artist_id
confMat[real_artist_id,pred_artist_id] += 1
# done, print out
print 'nExps:',nExps
print 'rand accuracy:',(randScore*1./nExps)
print 'accuracy:',(nGood*1./nExps)
# plot confusion matrix
if confMatrix:
short_names = np.array([x[:2] for x in artist_names])
import pylab as P
P.imshow(confMat,interpolation='nearest',cmap=P.cm.gray_r,
origin='lower')
P.yticks(P.arange(artist_names.shape[0]),list(artist_names))
P.xticks(P.arange(artist_names.shape[0]),list(short_names))
P.title('confusion matrix (real/predicted)')
P.ylabel('TRUE')
P.xlabel('RECOG')
P.colorbar()
# return confusion matrix
return confMat,freqs,artists