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hub / github.com/IceClear/StableSR / plms_sampling

Method plms_sampling

ldm/models/diffusion/plms.py:115–170  ·  view source on GitHub ↗
(self, cond, shape,
                      x_T=None, ddim_use_original_steps=False,
                      callback=None, timesteps=None, quantize_denoised=False,
                      mask=None, x0=None, img_callback=None, log_every_t=100,
                      temperature=1., noise_dropout=0., score_corrector=None, corrector_kwargs=None,
                      unconditional_guidance_scale=1., unconditional_conditioning=None,)

Source from the content-addressed store, hash-verified

113
114 @torch.no_grad()
115 def plms_sampling(self, cond, shape,
116 x_T=None, ddim_use_original_steps=False,
117 callback=None, timesteps=None, quantize_denoised=False,
118 mask=None, x0=None, img_callback=None, log_every_t=100,
119 temperature=1., noise_dropout=0., score_corrector=None, corrector_kwargs=None,
120 unconditional_guidance_scale=1., unconditional_conditioning=None,):
121 device = self.model.betas.device
122 b = shape[0]
123 if x_T is None:
124 img = torch.randn(shape, device=device)
125 else:
126 img = x_T
127
128 if timesteps is None:
129 timesteps = self.ddpm_num_timesteps if ddim_use_original_steps else self.ddim_timesteps
130 elif timesteps is not None and not ddim_use_original_steps:
131 subset_end = int(min(timesteps / self.ddim_timesteps.shape[0], 1) * self.ddim_timesteps.shape[0]) - 1
132 timesteps = self.ddim_timesteps[:subset_end]
133
134 intermediates = {'x_inter': [img], 'pred_x0': [img]}
135 time_range = list(reversed(range(0,timesteps))) if ddim_use_original_steps else np.flip(timesteps)
136 total_steps = timesteps if ddim_use_original_steps else timesteps.shape[0]
137 print(f"Running PLMS Sampling with {total_steps} timesteps")
138
139 iterator = tqdm(time_range, desc='PLMS Sampler', total=total_steps)
140 old_eps = []
141
142 for i, step in enumerate(iterator):
143 index = total_steps - i - 1
144 ts = torch.full((b,), step, device=device, dtype=torch.long)
145 ts_next = torch.full((b,), time_range[min(i + 1, len(time_range) - 1)], device=device, dtype=torch.long)
146
147 if mask is not None:
148 assert x0 is not None
149 img_orig = self.model.q_sample(x0, ts) # TODO: deterministic forward pass?
150 img = img_orig * mask + (1. - mask) * img
151
152 outs = self.p_sample_plms(img, cond, ts, index=index, use_original_steps=ddim_use_original_steps,
153 quantize_denoised=quantize_denoised, temperature=temperature,
154 noise_dropout=noise_dropout, score_corrector=score_corrector,
155 corrector_kwargs=corrector_kwargs,
156 unconditional_guidance_scale=unconditional_guidance_scale,
157 unconditional_conditioning=unconditional_conditioning,
158 old_eps=old_eps, t_next=ts_next)
159 img, pred_x0, e_t = outs
160 old_eps.append(e_t)
161 if len(old_eps) >= 4:
162 old_eps.pop(0)
163 if callback: callback(i)
164 if img_callback: img_callback(pred_x0, i)
165
166 if index % log_every_t == 0 or index == total_steps - 1:
167 intermediates['x_inter'].append(img)
168 intermediates['pred_x0'].append(pred_x0)
169
170 return img, intermediates
171
172 @torch.no_grad()

Callers 1

sampleMethod · 0.95

Calls 3

p_sample_plmsMethod · 0.95
callbackFunction · 0.85
q_sampleMethod · 0.45

Tested by

no test coverage detected