DL-Art-School/codes/models/gpt_voice/lucidrains_dvae.py
2021-08-14 23:43:01 -06:00

209 lines
6.8 KiB
Python

import math
from math import sqrt
import torch
import torch.nn as nn
import torch.nn.functional as F
from einops import rearrange
from torch import einsum
from models.vqvae.vqvae import Quantize
from trainer.networks import register_model
from utils.util import opt_get
def default(val, d):
return val if val is not None else d
def eval_decorator(fn):
def inner(model, *args, **kwargs):
was_training = model.training
model.eval()
out = fn(model, *args, **kwargs)
model.train(was_training)
return out
return inner
class ResBlock(nn.Module):
def __init__(self, chan, conv):
super().__init__()
self.net = nn.Sequential(
conv(chan, chan, 3, padding = 1),
nn.ReLU(),
conv(chan, chan, 3, padding = 1),
nn.ReLU(),
conv(chan, chan, 1)
)
def forward(self, x):
return self.net(x) + x
class DiscreteVAE(nn.Module):
def __init__(
self,
positional_dims=2,
num_tokens = 512,
codebook_dim = 512,
num_layers = 3,
num_resnet_blocks = 0,
hidden_dim = 64,
channels = 3,
smooth_l1_loss = False,
straight_through = False,
normalization = None, # ((0.5,) * 3, (0.5,) * 3),
record_codes = False,
):
super().__init__()
assert num_layers >= 1, 'number of layers must be greater than or equal to 1'
has_resblocks = num_resnet_blocks > 0
self.num_tokens = num_tokens
self.num_layers = num_layers
self.straight_through = straight_through
self.codebook = Quantize(codebook_dim, num_tokens)
self.positional_dims = positional_dims
assert positional_dims > 0 and positional_dims < 3 # This VAE only supports 1d and 2d inputs for now.
if positional_dims == 2:
conv = nn.Conv2d
conv_transpose = nn.ConvTranspose2d
else:
conv = nn.Conv1d
conv_transpose = nn.ConvTranspose1d
enc_chans = [hidden_dim] * num_layers
dec_chans = list(reversed(enc_chans))
enc_chans = [channels, *enc_chans]
dec_init_chan = codebook_dim if not has_resblocks else dec_chans[0]
dec_chans = [dec_init_chan, *dec_chans]
enc_chans_io, dec_chans_io = map(lambda t: list(zip(t[:-1], t[1:])), (enc_chans, dec_chans))
enc_layers = []
dec_layers = []
for (enc_in, enc_out), (dec_in, dec_out) in zip(enc_chans_io, dec_chans_io):
enc_layers.append(nn.Sequential(conv(enc_in, enc_out, 4, stride = 2, padding = 1), nn.ReLU()))
dec_layers.append(nn.Sequential(conv_transpose(dec_in, dec_out, 4, stride = 2, padding = 1), nn.ReLU()))
for _ in range(num_resnet_blocks):
dec_layers.insert(0, ResBlock(dec_chans[1], conv))
enc_layers.append(ResBlock(enc_chans[-1], conv))
if num_resnet_blocks > 0:
dec_layers.insert(0, conv(codebook_dim, dec_chans[1], 1))
enc_layers.append(conv(enc_chans[-1], codebook_dim, 1))
dec_layers.append(conv(dec_chans[-1], channels, 1))
self.encoder = nn.Sequential(*enc_layers)
self.decoder = nn.Sequential(*dec_layers)
self.loss_fn = F.smooth_l1_loss if smooth_l1_loss else F.mse_loss
# take care of normalization within class
self.normalization = normalization
self.record_codes = record_codes
if record_codes:
self.codes = torch.zeros((32768,), dtype=torch.long)
self.code_ind = 0
self.internal_step = 0
def norm(self, images):
if not self.normalization is not None:
return images
means, stds = map(lambda t: torch.as_tensor(t).to(images), self.normalization)
arrange = 'c -> () c () ()' if self.positional_dims == 2 else 'c -> () c ()'
means, stds = map(lambda t: rearrange(t, arrange), (means, stds))
images = images.clone()
images.sub_(means).div_(stds)
return images
def get_debug_values(self, step, __):
if self.record_codes:
# Report annealing schedule
return {'histogram_codes': self.codes}
else:
return {}
@torch.no_grad()
@eval_decorator
def get_codebook_indices(self, images):
img = self.norm(images)
logits = self.encoder(img).permute((0,2,3,1) if len(img.shape) == 4 else (0,2,1))
sampled, commitment_loss, codes = self.codebook(logits)
return codes
def decode(
self,
img_seq
):
image_embeds = self.codebook.embed_code(img_seq)
b, n, d = image_embeds.shape
kwargs = {}
if self.positional_dims == 1:
arrange = 'b n d -> b d n'
else:
h = w = int(sqrt(n))
arrange = 'b (h w) d -> b d h w'
kwargs = {'h': h, 'w': w}
image_embeds = rearrange(image_embeds, arrange, **kwargs)
images = self.decoder(image_embeds)
return images
# Note: This module is not meant to be run in forward() except while training. It has special logic which performs
# evaluation using quantized values when it detects that it is being run in eval() mode, which will be substantially
# more lossy (but useful for determining network performance).
def forward(
self,
img
):
img = self.norm(img)
logits = self.encoder(img).permute((0,2,3,1) if len(img.shape) == 4 else (0,2,1))
sampled, commitment_loss, codes = self.codebook(logits)
sampled = sampled.permute((0,3,1,2) if len(img.shape) == 4 else (0,2,1))
if self.training:
out = self.decoder(sampled)
else:
# This is non-differentiable, but gives a better idea of how the network is actually performing.
out = self.decode(codes)
# reconstruction loss
recon_loss = self.loss_fn(img, out)
# This is so we can debug the distribution of codes being learned.
if self.record_codes and self.internal_step % 50 == 0:
codes = codes.flatten()
l = codes.shape[0]
i = self.code_ind if (self.codes.shape[0] - self.code_ind) > l else self.codes.shape[0] - l
self.codes[i:i+l] = codes.cpu()
self.code_ind = self.code_ind + l
if self.code_ind >= self.codes.shape[0]:
self.code_ind = 0
self.internal_step += 1
return recon_loss, commitment_loss, out
@register_model
def register_lucidrains_dvae(opt_net, opt):
return DiscreteVAE(**opt_get(opt_net, ['kwargs'], {}))
if __name__ == '__main__':
#v = DiscreteVAE()
#o=v(torch.randn(1,3,256,256))
#print(o.shape)
v = DiscreteVAE(channels=1, normalization=None, positional_dims=1, num_tokens=4096, codebook_dim=2048, hidden_dim=256)
v.eval()
o=v(torch.randn(1,1,256))
print(o[-1].shape)