def decode_one_idx(self, prev_idx):
mode = bits2int(self.stream[self.ct:self.ct + 1], is_uint=True)
self.ct += 1
if mode == 1:
idx = bits2int(self.stream[self.ct:self.ct + self.length],
is_uint=True)
self.ct += self.length
return idx
else:
pred = self.learner.predict(np.array(prev_idx).reshape(1, -1))
return pred
def decode_fail(self, idx):
mode = bits2int(self.stream[self.ct:self.ct + 2], is_uint=True)
self.ct += 2
if mode < 3:
a = idx[-4:-1]
a.sort()
return a[mode]
else:
b = idx[:-4]
b.sort()
val = bits2int(self.stream[self.ct:self.ct + self.length],
is_uint=True)
self.ct += self.length
return b[val]
def decode_one_idx(self, prev_idx, mode):
self.get_MPM(prev_idx)
if mode == 3:
idx = bits2int(self.stream[self.ct:self.ct + self.length],
is_uint=True)
self.ct += self.length
return self.codeword_list[idx]
else:
return self.MPM_list[mode]
def decode_one_idx(self, prev_idx):
mode = bits2int(self.stream[self.ct:self.ct + 2], is_uint=True)
self.ct += 2
prob = self.learner.predict_proba(np.array(prev_idx).reshape(
1, -1)).reshape(-1)
pred = np.argsort(prob)[-3:]
pred.sort()
if mode == 3:
codeword = []
for i in range(self.n_codeword):
if i not in pred:
codeword.append(i)
idx = bits2int(self.stream[self.ct:self.ct + self.length],
is_uint=True)
self.ct += self.length
return codeword[idx]
else:
return pred[mode]
def decode_one_idx(self, prev_idx):
mode = bits2int(self.stream[self.ct:self.ct + 1], is_uint=True)
self.ct += 1
prob = self.learner.predict_proba(np.array(prev_idx).reshape(
1, -1)).reshape(-1)
if mode == 1:
idx = self.decode_fail(np.argsort(prob))
return idx
else:
return np.argmax(prob)
def decode(self, stream, H, W):
self.stream = stream
idx = np.zeros((H, W))
self.ct = 0
for i in range(idx.shape[0]):
for j in range(idx.shape[1]):
prev_idx = [
self.get_prev(idx, i - 1, j - 1),
self.get_prev(idx, i - 1, j),
self.get_prev(idx, i, j - 1)
]
mode = bits2int(self.stream[self.ct:self.ct + 2], is_uint=True)
self.ct += 2
idx[i, j] = self.decode_one_idx(prev_idx, mode)
return idx.astype('int16')