cooelf's picture
update
a6dac9a
raw
history blame
3.38 kB
""" Model / state_dict utils
Hacked together by / Copyright 2020 Ross Wightman
"""
from .model_ema import ModelEma
import torch
import fnmatch
def unwrap_model(model):
if isinstance(model, ModelEma):
return unwrap_model(model.ema)
else:
return model.module if hasattr(model, 'module') else model
def get_state_dict(model, unwrap_fn=unwrap_model):
return unwrap_fn(model).state_dict()
def avg_sq_ch_mean(model, input, output):
"calculate average channel square mean of output activations"
return torch.mean(output.mean(axis=[0,2,3])**2).item()
def avg_ch_var(model, input, output):
"calculate average channel variance of output activations"
return torch.mean(output.var(axis=[0,2,3])).item()\
def avg_ch_var_residual(model, input, output):
"calculate average channel variance of output activations"
return torch.mean(output.var(axis=[0,2,3])).item()
class ActivationStatsHook:
"""Iterates through each of `model`'s modules and matches modules using unix pattern
matching based on `hook_fn_locs` and registers `hook_fn` to the module if there is
a match.
Arguments:
model (nn.Module): model from which we will extract the activation stats
hook_fn_locs (List[str]): List of `hook_fn` locations based on Unix type string
matching with the name of model's modules.
hook_fns (List[Callable]): List of hook functions to be registered at every
module in `layer_names`.
Inspiration from https://docs.fast.ai/callback.hook.html.
Refer to https://gist.github.com/amaarora/6e56942fcb46e67ba203f3009b30d950 for an example
on how to plot Signal Propogation Plots using `ActivationStatsHook`.
"""
def __init__(self, model, hook_fn_locs, hook_fns):
self.model = model
self.hook_fn_locs = hook_fn_locs
self.hook_fns = hook_fns
if len(hook_fn_locs) != len(hook_fns):
raise ValueError("Please provide `hook_fns` for each `hook_fn_locs`, \
their lengths are different.")
self.stats = dict((hook_fn.__name__, []) for hook_fn in hook_fns)
for hook_fn_loc, hook_fn in zip(hook_fn_locs, hook_fns):
self.register_hook(hook_fn_loc, hook_fn)
def _create_hook(self, hook_fn):
def append_activation_stats(module, input, output):
out = hook_fn(module, input, output)
self.stats[hook_fn.__name__].append(out)
return append_activation_stats
def register_hook(self, hook_fn_loc, hook_fn):
for name, module in self.model.named_modules():
if not fnmatch.fnmatch(name, hook_fn_loc):
continue
module.register_forward_hook(self._create_hook(hook_fn))
def extract_spp_stats(model,
hook_fn_locs,
hook_fns,
input_shape=[8, 3, 224, 224]):
"""Extract average square channel mean and variance of activations during
forward pass to plot Signal Propogation Plots (SPP).
Paper: https://arxiv.org/abs/2101.08692
Example Usage: https://gist.github.com/amaarora/6e56942fcb46e67ba203f3009b30d950
"""
x = torch.normal(0., 1., input_shape)
hook = ActivationStatsHook(model, hook_fn_locs=hook_fn_locs, hook_fns=hook_fns)
_ = model(x)
return hook.stats