def apply(self,
input_ids,
input_mask,
type_ids,
*,
config,
deterministic=False):
"""Applies BERT model on the inputs."""
word_embeddings = nn.Embed(input_ids,
num_embeddings=config.vocab_size,
features=config.d_emb,
embedding_init=kernel_initializer,
name="word_embeddings")
position_embeddings = layers.PositionalEncoding(
word_embeddings,
max_len=config.max_len,
posemb_init=kernel_initializer,
name="position_embeddings")
type_embeddings = nn.Embed(type_ids,
num_embeddings=config.type_vocab_size,
features=config.d_emb,
embedding_init=kernel_initializer,
name="type_embeddings")
embeddings = word_embeddings + position_embeddings + type_embeddings
embeddings = nn.LayerNorm(embeddings,
epsilon=LAYER_NORM_EPSILON,
name="embeddings_layer_norm")
embeddings = nn.Dense(embeddings,
config.d_model,
name="embedding_hidden_mapping_in")
embeddings = nn.dropout(embeddings,
rate=config.dropout_rate,
deterministic=deterministic)
# Transformer blocks
feed_forward = layers.FeedForward.partial(
d_ff=config.d_ff,
dropout_rate=config.dropout_rate,
intermediate_activation=hidden_activation,
kernel_init=kernel_initializer)
self_attention = efficient_attention.BertSelfAttention.partial(
num_heads=config.num_heads,
num_parallel_heads=config.num_parallel_heads,
d_qkv=config.d_model // config.num_heads,
attention_dropout_rate=config.attention_dropout_rate,
output_dropout_rate=config.dropout_rate,
kernel_init=kernel_initializer,
output_kernel_init=kernel_initializer)
hidden_states = embeddings
mask = input_mask.astype(jnp.int32)
shared_encoder_layer = layers.TransformerBlock.shared(
feed_forward=feed_forward,
attention=self_attention,
deterministic=deterministic,
name="encoder_layer_0")
for _ in range(config.num_layers):
hidden_states = shared_encoder_layer(hidden_states, mask)
pooled_output = nn.Dense(hidden_states[:, 0],
config.d_model,
kernel_init=kernel_initializer,
name="pooler")
pooled_output = jnp.tanh(pooled_output)
return hidden_states, pooled_output
def apply(self,
input_ids,
input_mask,
type_ids,
*,
config,
deterministic=False):
"""Applies BERT model on the inputs."""
word_embeddings = nn.Embed(input_ids,
num_embeddings=config.vocab_size,
features=config.hidden_size,
embedding_init=get_kernel_init(config),
name='word_embeddings')
position_embeddings = layers.PositionalEncoding(
word_embeddings,
max_len=config.max_position_embeddings,
posemb_init=get_kernel_init(config),
name='position_embeddings')
type_embeddings = nn.Embed(type_ids,
num_embeddings=config.type_vocab_size,
features=config.hidden_size,
embedding_init=get_kernel_init(config),
name='type_embeddings')
embeddings = word_embeddings + position_embeddings + type_embeddings
embeddings = nn.LayerNorm(embeddings,
epsilon=LAYER_NORM_EPSILON,
name='embeddings_layer_norm')
embeddings = nn.dropout(embeddings,
rate=config.hidden_dropout_prob,
deterministic=deterministic)
# Transformer blocks
feed_forward = layers.FeedForward.partial(
d_ff=config.intermediate_size,
dropout_rate=config.hidden_dropout_prob,
intermediate_activation=get_hidden_activation(config),
kernel_init=get_kernel_init(config))
attention = efficient_attention.BertSelfAttention.partial(
num_heads=config.num_attention_heads,
num_parallel_heads=None,
d_qkv=config.hidden_size // config.num_attention_heads,
attention_dropout_rate=config.attention_probs_dropout_prob,
output_dropout_rate=config.hidden_dropout_prob,
kernel_init=get_kernel_init(config),
output_kernel_init=get_kernel_init(config))
hidden_states = embeddings
mask = input_mask.astype(jnp.int32)
for layer_num in range(config.num_hidden_layers):
hidden_states = layers.TransformerBlock(
hidden_states,
mask,
feed_forward=feed_forward,
attention=attention,
deterministic=deterministic,
name=f'encoder_layer_{layer_num}')
pooled_output = nn.Dense(hidden_states[:, 0],
config.hidden_size,
kernel_init=get_kernel_init(config),
name='pooler')
pooled_output = jnp.tanh(pooled_output)
return hidden_states, pooled_output
def apply(self, x, labels, y=None, config=None, train=True):
# config parsing
nf = config.model.nf
act = get_act(config)
normalize = get_normalization(config)
sigmas = utils.get_sigmas(config)
nf = config.model.nf
ch_mult = config.model.ch_mult
num_res_blocks = config.model.num_res_blocks
attn_resolutions = config.model.attn_resolutions
dropout = config.model.dropout
resamp_with_conv = config.model.resamp_with_conv
num_resolutions = len(ch_mult)
conditional = config.model.conditional # noise-conditional
fir = config.model.fir
fir_kernel = config.model.fir_kernel
skip_rescale = config.model.skip_rescale
resblock_type = config.model.resblock_type
progressive = config.model.progressive
progressive_input = config.model.progressive_input
init_scale = config.model.init_scale
assert progressive.lower() in ['none', 'output_skip', 'residual']
assert config.model.embedding_type.lower() in ['gaussian', 'positional']
combine_method = config.model.progressive_combine
combiner = Combine.partial(method=combine_method)
# timestep/noise_level embedding
if config.model.embedding_type == 'gaussian':
# Gaussian Fourier features embeddings.
used_sigmas = sigmas[labels]
temb = layersv3.GaussianFourierProjection(
jnp.log(used_sigmas),
embedding_size=nf,
scale=config.model.fourier_scale)
elif config.model.embedding_type == 'positional':
# Sinusoidal positional embeddings.
timesteps = labels
temb = layers.get_timestep_embedding(timesteps, nf)
else:
raise ValueError(f'embedding type {config.model.embedding_type} unknown.')
temb = nn.Dense(temb, nf * 4, kernel_init=default_initializer())
temb = nn.Dense(act(temb), nf * 4, kernel_init=default_initializer())
if y is not None: # class-conditional image generation
class_embed = nn.Embed(y, config.data.num_classes, nf * 4)
class_embed = nn.Dense(
class_embed, nf * 4, kernel_init=default_initializer())
class_embed = nn.Dense(
act(class_embed), nf * 4, kernel_init=default_initializer())
temb += class_embed
AttnBlock = layersv3.AttnBlockv3.partial(
normalize=normalize,
init_scale=init_scale,
skip_rescale=skip_rescale)
Upsample = layersv3.Upsample.partial(
with_conv=resamp_with_conv, fir=fir, fir_kernel=fir_kernel)
if progressive == 'output_skip':
pyramid_upsample = layersv3.Upsample.partial(
fir=fir, fir_kernel=fir_kernel, with_conv=False)
elif progressive == 'residual':
pyramid_upsample = layersv3.Upsample.partial(
fir=fir, fir_kernel=fir_kernel, with_conv=True)
Downsample = layersv3.Downsample.partial(
with_conv=resamp_with_conv, fir=fir, fir_kernel=fir_kernel)
if progressive_input == 'input_skip':
pyramid_downsample = layersv3.Downsample.partial(
fir=fir, fir_kernel=fir_kernel, with_conv=False)
elif progressive_input == 'residual':
pyramid_downsample = layersv3.Downsample.partial(
fir=fir, fir_kernel=fir_kernel, with_conv=True)
if resblock_type == 'ddpm':
ResnetBlock = ResnetBlockDDPM.partial(
act=act,
normalize=normalize,
dropout=dropout,
temb=temb if conditional else None,
train=train,
init_scale=init_scale,
skip_rescale=skip_rescale)
elif resblock_type == 'biggan':
ResnetBlock = ResnetBlockBigGAN.partial(
act=act,
normalize=normalize,
temb=temb if conditional else None,
train=train,
dropout=dropout,
fir=fir,
fir_kernel=fir_kernel,
init_scale=init_scale,
skip_rescale=skip_rescale)
else:
raise ValueError(f'resblock_type {resblock_type} unrecognized.')
if not config.data.centered:
# If input data is in [0, 1]
x = 2 * x - 1.
# Downsampling block
input_pyramid = None
if progressive_input != 'none':
input_pyramid = x
hs = [conv3x3(x, nf)]
for i_level in range(num_resolutions):
# Residual blocks for this resolution
for i_block in range(num_res_blocks):
h = ResnetBlock(hs[-1], out_ch=nf * ch_mult[i_level])
if h.shape[1] in attn_resolutions:
h = AttnBlock(h)
hs.append(h)
if i_level != num_resolutions - 1:
if resblock_type == 'ddpm':
h = Downsample(hs[-1])
else:
h = ResnetBlock(hs[-1], down=True)
if progressive_input == 'input_skip':
input_pyramid = pyramid_downsample(input_pyramid)
h = combiner(input_pyramid, h)
elif progressive_input == 'residual':
input_pyramid = pyramid_downsample(
input_pyramid, out_ch=h.shape[-1])
if skip_rescale:
input_pyramid = (input_pyramid + h) / np.sqrt(2.)
else:
input_pyramid = input_pyramid + h
h = input_pyramid
hs.append(h)
h = hs[-1]
h = ResnetBlock(h)
h = AttnBlock(h)
h = ResnetBlock(h)
pyramid = None
# Upsampling block
for i_level in reversed(range(num_resolutions)):
for i_block in range(num_res_blocks + 1):
h = ResnetBlock(
jnp.concatenate([h, hs.pop()], axis=-1),
out_ch=nf * ch_mult[i_level])
if h.shape[1] in attn_resolutions:
h = AttnBlock(h)
if progressive != 'none':
if i_level == num_resolutions - 1:
if progressive == 'output_skip':
pyramid = conv3x3(
act(normalize(h, num_groups=min(h.shape[-1] // 4, 32))),
x.shape[-1],
bias=True,
init_scale=init_scale)
elif progressive == 'residual':
pyramid = conv3x3(
act(normalize(h, num_groups=min(h.shape[-1] // 4, 32))),
h.shape[-1],
bias=True)
else:
raise ValueError(f'{progressive} is not a valid name.')
else:
if progressive == 'output_skip':
pyramid = pyramid_upsample(pyramid)
pyramid = pyramid + conv3x3(
act(normalize(h, num_groups=min(h.shape[-1] // 4, 32))),
x.shape[-1],
bias=True,
init_scale=init_scale)
elif progressive == 'residual':
pyramid = pyramid_upsample(pyramid, out_ch=h.shape[-1])
if skip_rescale:
pyramid = (pyramid + h) / np.sqrt(2.)
else:
pyramid = pyramid + h
h = pyramid
else:
raise ValueError(f'{progressive} is not a valid name')
if i_level != 0:
if resblock_type == 'ddpm':
h = Upsample(h)
else:
h = ResnetBlock(h, up=True)
assert not hs
if progressive == 'output_skip':
h = pyramid
else:
h = act(normalize(h, num_groups=min(h.shape[-1] // 4, 32)))
h = conv3x3(h, x.shape[-1], init_scale=init_scale)
if config.model.scale_by_sigma:
used_sigmas = sigmas[labels].reshape((x.shape[0],
*([1] * len(x.shape[1:]))))
h = h / used_sigmas
return h
