Add iris_model.py
Browse files- iris_model.py +1246 -0
iris_model.py
ADDED
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@@ -0,0 +1,1246 @@
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|
| 1 |
+
"""
|
| 2 |
+
IRIS: Iterative Recurrent Image Synthesis
|
| 3 |
+
==========================================
|
| 4 |
+
A novel architecture for mobile-first high-quality image generation.
|
| 5 |
+
|
| 6 |
+
Key innovations:
|
| 7 |
+
1. Wavelet-Frequency Latent Space (Haar DWT + lightweight VAE)
|
| 8 |
+
2. Recurrent Depth Core (Prelude-Core-Coda with shared weights)
|
| 9 |
+
3. Gated Recurrent Fourier Mixer (GRFM) — novel token mixing
|
| 10 |
+
4. Manhattan Spatial Decay — learned 2D inductive bias
|
| 11 |
+
5. Rectified Flow training with consistency distillation support
|
| 12 |
+
6. Adaptive compute budget (4-16 iterations, same model)
|
| 13 |
+
|
| 14 |
+
Author: IRIS Research
|
| 15 |
+
License: Apache 2.0
|
| 16 |
+
"""
|
| 17 |
+
|
| 18 |
+
import math
|
| 19 |
+
import torch
|
| 20 |
+
import torch.nn as nn
|
| 21 |
+
import torch.nn.functional as F
|
| 22 |
+
from typing import Optional, Tuple
|
| 23 |
+
from dataclasses import dataclass, field
|
| 24 |
+
|
| 25 |
+
|
| 26 |
+
# ============================================================================
|
| 27 |
+
# Configuration
|
| 28 |
+
# ============================================================================
|
| 29 |
+
|
| 30 |
+
@dataclass
|
| 31 |
+
class IRISConfig:
|
| 32 |
+
"""Configuration for IRIS model."""
|
| 33 |
+
# Latent space
|
| 34 |
+
latent_channels: int = 16 # Channels in latent space
|
| 35 |
+
latent_spatial: int = 32 # Spatial dim of latent (for 512px with 16x compression)
|
| 36 |
+
|
| 37 |
+
# Model dimensions
|
| 38 |
+
hidden_dim: int = 512 # Main hidden dimension
|
| 39 |
+
num_heads: int = 8 # Number of attention heads
|
| 40 |
+
head_dim: int = 64 # Dimension per head
|
| 41 |
+
ffn_ratio: float = 2.667 # FFN expansion ratio (SwiGLU-adjusted)
|
| 42 |
+
|
| 43 |
+
# Architecture structure
|
| 44 |
+
num_prelude_blocks: int = 2 # Prelude blocks (unique weights)
|
| 45 |
+
num_core_layers: int = 4 # Layers WITHIN each core iteration
|
| 46 |
+
num_coda_blocks: int = 2 # Coda blocks (unique weights)
|
| 47 |
+
default_iterations: int = 8 # Default core iterations at inference
|
| 48 |
+
max_iterations: int = 16 # Maximum core iterations
|
| 49 |
+
|
| 50 |
+
# GRFM settings
|
| 51 |
+
fourier_num_blocks: int = 8 # Block-diagonal blocks in Fourier MLP
|
| 52 |
+
sparsity_threshold: float = 0.01 # Soft-shrinkage lambda
|
| 53 |
+
recurrence_dim: int = 256 # Dimension for gated recurrence pathway
|
| 54 |
+
manhattan_window: int = 16 # Windowed Manhattan decay (for efficiency)
|
| 55 |
+
|
| 56 |
+
# Cross-attention
|
| 57 |
+
text_dim: int = 768 # CLIP-L/14 text embedding dim
|
| 58 |
+
max_text_tokens: int = 77 # Maximum text sequence length
|
| 59 |
+
|
| 60 |
+
# Patch embedding
|
| 61 |
+
patch_size: int = 2 # Patches in latent space (2×2)
|
| 62 |
+
|
| 63 |
+
# Conditioning
|
| 64 |
+
num_timesteps: int = 1000 # Noise schedule discretization
|
| 65 |
+
|
| 66 |
+
# VAE
|
| 67 |
+
vae_channels: list = field(default_factory=lambda: [32, 64, 128, 256])
|
| 68 |
+
|
| 69 |
+
# Training
|
| 70 |
+
dropout: float = 0.0
|
| 71 |
+
|
| 72 |
+
@property
|
| 73 |
+
def vae_latent_channels(self) -> int:
|
| 74 |
+
"""VAE latent channels must match generator latent channels."""
|
| 75 |
+
return self.latent_channels
|
| 76 |
+
|
| 77 |
+
@property
|
| 78 |
+
def num_patches(self) -> int:
|
| 79 |
+
return (self.latent_spatial // self.patch_size) ** 2
|
| 80 |
+
|
| 81 |
+
@property
|
| 82 |
+
def patch_dim(self) -> int:
|
| 83 |
+
return self.latent_channels * self.patch_size * self.patch_size
|
| 84 |
+
|
| 85 |
+
|
| 86 |
+
# ============================================================================
|
| 87 |
+
# Wavelet Transforms (Haar)
|
| 88 |
+
# ============================================================================
|
| 89 |
+
|
| 90 |
+
class HaarDWT2D(nn.Module):
|
| 91 |
+
"""2D Discrete Wavelet Transform using Haar wavelets.
|
| 92 |
+
Decomposes x ∈ R^{B,C,H,W} into R^{B,4C,H/2,W/2} (LL, LH, HL, HH subbands).
|
| 93 |
+
"""
|
| 94 |
+
def forward(self, x: torch.Tensor) -> torch.Tensor:
|
| 95 |
+
# Haar DWT: split into even/odd along both spatial dims
|
| 96 |
+
x_ll = (x[:, :, 0::2, 0::2] + x[:, :, 0::2, 1::2] +
|
| 97 |
+
x[:, :, 1::2, 0::2] + x[:, :, 1::2, 1::2]) * 0.5
|
| 98 |
+
x_lh = (x[:, :, 0::2, 0::2] + x[:, :, 0::2, 1::2] -
|
| 99 |
+
x[:, :, 1::2, 0::2] - x[:, :, 1::2, 1::2]) * 0.5
|
| 100 |
+
x_hl = (x[:, :, 0::2, 0::2] - x[:, :, 0::2, 1::2] +
|
| 101 |
+
x[:, :, 1::2, 0::2] - x[:, :, 1::2, 1::2]) * 0.5
|
| 102 |
+
x_hh = (x[:, :, 0::2, 0::2] - x[:, :, 0::2, 1::2] -
|
| 103 |
+
x[:, :, 1::2, 0::2] + x[:, :, 1::2, 1::2]) * 0.5
|
| 104 |
+
return torch.cat([x_ll, x_lh, x_hl, x_hh], dim=1)
|
| 105 |
+
|
| 106 |
+
|
| 107 |
+
class HaarIDWT2D(nn.Module):
|
| 108 |
+
"""2D Inverse Discrete Wavelet Transform (Haar).
|
| 109 |
+
Reconstructs x ∈ R^{B,C,H,W} from R^{B,4*(C//4),H/2,W/2}.
|
| 110 |
+
"""
|
| 111 |
+
def forward(self, x: torch.Tensor) -> torch.Tensor:
|
| 112 |
+
B, C4, Hh, Wh = x.shape
|
| 113 |
+
C = C4 // 4
|
| 114 |
+
ll, lh, hl, hh = x[:, :C], x[:, C:2*C], x[:, 2*C:3*C], x[:, 3*C:]
|
| 115 |
+
|
| 116 |
+
# Reconstruct 2× spatial resolution
|
| 117 |
+
H, W = Hh * 2, Wh * 2
|
| 118 |
+
out = torch.zeros(B, C, H, W, device=x.device, dtype=x.dtype)
|
| 119 |
+
out[:, :, 0::2, 0::2] = (ll + lh + hl + hh) * 0.5
|
| 120 |
+
out[:, :, 0::2, 1::2] = (ll + lh - hl - hh) * 0.5
|
| 121 |
+
out[:, :, 1::2, 0::2] = (ll - lh + hl - hh) * 0.5
|
| 122 |
+
out[:, :, 1::2, 1::2] = (ll - lh - hl + hh) * 0.5
|
| 123 |
+
return out
|
| 124 |
+
|
| 125 |
+
|
| 126 |
+
# ============================================================================
|
| 127 |
+
# Lightweight Wavelet VAE
|
| 128 |
+
# ============================================================================
|
| 129 |
+
|
| 130 |
+
class DepthwiseSeparableConv(nn.Module):
|
| 131 |
+
"""Depthwise separable convolution — key mobile optimization."""
|
| 132 |
+
def __init__(self, in_ch, out_ch, kernel_size=3, stride=1, padding=1):
|
| 133 |
+
super().__init__()
|
| 134 |
+
self.depthwise = nn.Conv2d(in_ch, in_ch, kernel_size, stride, padding, groups=in_ch)
|
| 135 |
+
self.pointwise = nn.Conv2d(in_ch, out_ch, 1)
|
| 136 |
+
|
| 137 |
+
def forward(self, x):
|
| 138 |
+
return self.pointwise(self.depthwise(x))
|
| 139 |
+
|
| 140 |
+
|
| 141 |
+
class ResBlock(nn.Module):
|
| 142 |
+
"""Residual block with depthwise separable convolutions."""
|
| 143 |
+
def __init__(self, channels):
|
| 144 |
+
super().__init__()
|
| 145 |
+
self.norm1 = nn.GroupNorm(8, channels)
|
| 146 |
+
self.conv1 = DepthwiseSeparableConv(channels, channels)
|
| 147 |
+
self.norm2 = nn.GroupNorm(8, channels)
|
| 148 |
+
self.conv2 = DepthwiseSeparableConv(channels, channels)
|
| 149 |
+
# Zero-init final layer for residual learning stability
|
| 150 |
+
nn.init.zeros_(self.conv2.pointwise.weight)
|
| 151 |
+
nn.init.zeros_(self.conv2.pointwise.bias)
|
| 152 |
+
|
| 153 |
+
def forward(self, x):
|
| 154 |
+
h = F.silu(self.norm1(x))
|
| 155 |
+
h = self.conv1(h)
|
| 156 |
+
h = F.silu(self.norm2(h))
|
| 157 |
+
h = self.conv2(h)
|
| 158 |
+
return x + h
|
| 159 |
+
|
| 160 |
+
|
| 161 |
+
class WaveletVAEEncoder(nn.Module):
|
| 162 |
+
"""Lightweight encoder: Haar DWT preprocessing + small convolutional encoder.
|
| 163 |
+
Input: images R^{B,3,H,W} → Output: latent R^{B,C_latent,H/16,W/16}
|
| 164 |
+
Compression: 3×H×W → C_latent×(H/16)×(W/16)
|
| 165 |
+
"""
|
| 166 |
+
def __init__(self, config: IRISConfig):
|
| 167 |
+
super().__init__()
|
| 168 |
+
self.dwt = HaarDWT2D()
|
| 169 |
+
channels = config.vae_channels
|
| 170 |
+
latent_ch = config.vae_latent_channels
|
| 171 |
+
|
| 172 |
+
# DWT: 3 channels → 12 channels at H/2 × W/2
|
| 173 |
+
self.conv_in = nn.Conv2d(12, channels[0], 3, 1, 1)
|
| 174 |
+
|
| 175 |
+
# Downsampling path: H/2→H/4→H/8→H/16
|
| 176 |
+
self.down_blocks = nn.ModuleList()
|
| 177 |
+
for i in range(len(channels) - 1):
|
| 178 |
+
self.down_blocks.append(nn.Sequential(
|
| 179 |
+
ResBlock(channels[i]),
|
| 180 |
+
nn.Conv2d(channels[i], channels[i+1], 3, 2, 1), # 2× downsample
|
| 181 |
+
))
|
| 182 |
+
|
| 183 |
+
# Bottleneck
|
| 184 |
+
self.mid = nn.Sequential(
|
| 185 |
+
ResBlock(channels[-1]),
|
| 186 |
+
ResBlock(channels[-1]),
|
| 187 |
+
)
|
| 188 |
+
|
| 189 |
+
# To latent (mean + logvar)
|
| 190 |
+
self.norm_out = nn.GroupNorm(8, channels[-1])
|
| 191 |
+
self.conv_out = nn.Conv2d(channels[-1], 2 * latent_ch, 1)
|
| 192 |
+
|
| 193 |
+
def forward(self, x: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor]:
|
| 194 |
+
# Haar DWT preprocessing
|
| 195 |
+
x = self.dwt(x) # [B, 12, H/2, W/2]
|
| 196 |
+
x = self.conv_in(x)
|
| 197 |
+
|
| 198 |
+
for down in self.down_blocks:
|
| 199 |
+
x = down(x)
|
| 200 |
+
|
| 201 |
+
x = self.mid(x)
|
| 202 |
+
x = F.silu(self.norm_out(x))
|
| 203 |
+
x = self.conv_out(x)
|
| 204 |
+
|
| 205 |
+
mean, logvar = x.chunk(2, dim=1)
|
| 206 |
+
logvar = torch.clamp(logvar, -30.0, 20.0)
|
| 207 |
+
return mean, logvar
|
| 208 |
+
|
| 209 |
+
def encode(self, x: torch.Tensor) -> torch.Tensor:
|
| 210 |
+
mean, logvar = self.forward(x)
|
| 211 |
+
std = torch.exp(0.5 * logvar)
|
| 212 |
+
z = mean + std * torch.randn_like(std)
|
| 213 |
+
return z, mean, logvar
|
| 214 |
+
|
| 215 |
+
|
| 216 |
+
class WaveletVAEDecoder(nn.Module):
|
| 217 |
+
"""Tiny decoder: latent → wavelet coefficients → Haar IDWT → image.
|
| 218 |
+
Designed to be as small as possible for mobile inference.
|
| 219 |
+
"""
|
| 220 |
+
def __init__(self, config: IRISConfig):
|
| 221 |
+
super().__init__()
|
| 222 |
+
channels = list(reversed(config.vae_channels))
|
| 223 |
+
latent_ch = config.vae_latent_channels
|
| 224 |
+
self.idwt = HaarIDWT2D()
|
| 225 |
+
|
| 226 |
+
# From latent
|
| 227 |
+
self.conv_in = nn.Conv2d(latent_ch, channels[0], 3, 1, 1)
|
| 228 |
+
|
| 229 |
+
# Bottleneck
|
| 230 |
+
self.mid = nn.Sequential(
|
| 231 |
+
ResBlock(channels[0]),
|
| 232 |
+
)
|
| 233 |
+
|
| 234 |
+
# Upsampling path
|
| 235 |
+
self.up_blocks = nn.ModuleList()
|
| 236 |
+
for i in range(len(channels) - 1):
|
| 237 |
+
self.up_blocks.append(nn.Sequential(
|
| 238 |
+
nn.Upsample(scale_factor=2, mode='nearest'),
|
| 239 |
+
DepthwiseSeparableConv(channels[i], channels[i+1]),
|
| 240 |
+
nn.SiLU(),
|
| 241 |
+
ResBlock(channels[i+1]),
|
| 242 |
+
))
|
| 243 |
+
|
| 244 |
+
# To wavelet coefficients (12 channels: 4 subbands × 3 color channels)
|
| 245 |
+
self.norm_out = nn.GroupNorm(8, channels[-1])
|
| 246 |
+
self.conv_out = nn.Conv2d(channels[-1], 12, 3, 1, 1)
|
| 247 |
+
|
| 248 |
+
def forward(self, z: torch.Tensor) -> torch.Tensor:
|
| 249 |
+
x = self.conv_in(z)
|
| 250 |
+
x = self.mid(x)
|
| 251 |
+
|
| 252 |
+
for up in self.up_blocks:
|
| 253 |
+
x = up(x)
|
| 254 |
+
|
| 255 |
+
x = F.silu(self.norm_out(x))
|
| 256 |
+
x = self.conv_out(x) # [B, 12, H/2, W/2] wavelet coefficients
|
| 257 |
+
|
| 258 |
+
# Inverse DWT to get image
|
| 259 |
+
x = self.idwt(x) # [B, 3, H, W]
|
| 260 |
+
return x
|
| 261 |
+
|
| 262 |
+
|
| 263 |
+
class WaveletVAE(nn.Module):
|
| 264 |
+
"""Complete Wavelet VAE with DWT preprocessing."""
|
| 265 |
+
def __init__(self, config: IRISConfig):
|
| 266 |
+
super().__init__()
|
| 267 |
+
self.encoder = WaveletVAEEncoder(config)
|
| 268 |
+
self.decoder = WaveletVAEDecoder(config)
|
| 269 |
+
self.config = config
|
| 270 |
+
|
| 271 |
+
def encode(self, x: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
|
| 272 |
+
return self.encoder.encode(x)
|
| 273 |
+
|
| 274 |
+
def decode(self, z: torch.Tensor) -> torch.Tensor:
|
| 275 |
+
return self.decoder(z)
|
| 276 |
+
|
| 277 |
+
def forward(self, x: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
|
| 278 |
+
z, mean, logvar = self.encode(x)
|
| 279 |
+
x_recon = self.decode(z)
|
| 280 |
+
return x_recon, mean, logvar
|
| 281 |
+
|
| 282 |
+
|
| 283 |
+
# ============================================================================
|
| 284 |
+
# Conditioning Modules
|
| 285 |
+
# ============================================================================
|
| 286 |
+
|
| 287 |
+
class TimestepEmbedding(nn.Module):
|
| 288 |
+
"""Sinusoidal timestep embedding with MLP projection."""
|
| 289 |
+
def __init__(self, dim: int, max_period: int = 10000):
|
| 290 |
+
super().__init__()
|
| 291 |
+
self.dim = dim
|
| 292 |
+
self.max_period = max_period
|
| 293 |
+
self.mlp = nn.Sequential(
|
| 294 |
+
nn.Linear(dim, 4 * dim),
|
| 295 |
+
nn.SiLU(),
|
| 296 |
+
nn.Linear(4 * dim, dim),
|
| 297 |
+
)
|
| 298 |
+
|
| 299 |
+
def forward(self, t: torch.Tensor) -> torch.Tensor:
|
| 300 |
+
half = self.dim // 2
|
| 301 |
+
freqs = torch.exp(
|
| 302 |
+
-math.log(self.max_period) * torch.arange(half, device=t.device, dtype=t.dtype) / half
|
| 303 |
+
)
|
| 304 |
+
args = t[:, None] * freqs[None, :]
|
| 305 |
+
embedding = torch.cat([torch.cos(args), torch.sin(args)], dim=-1)
|
| 306 |
+
return self.mlp(embedding)
|
| 307 |
+
|
| 308 |
+
|
| 309 |
+
class IterationEmbedding(nn.Module):
|
| 310 |
+
"""Learnable embedding for iteration index within recurrent core."""
|
| 311 |
+
def __init__(self, max_iterations: int, dim: int):
|
| 312 |
+
super().__init__()
|
| 313 |
+
self.embedding = nn.Embedding(max_iterations, dim)
|
| 314 |
+
|
| 315 |
+
def forward(self, i: torch.Tensor) -> torch.Tensor:
|
| 316 |
+
return self.embedding(i)
|
| 317 |
+
|
| 318 |
+
|
| 319 |
+
class AdaLNSingle(nn.Module):
|
| 320 |
+
"""Adaptive Layer Normalization (single shared MLP, per-layer bias).
|
| 321 |
+
From PixArt-α: saves 27% params vs standard adaLN.
|
| 322 |
+
|
| 323 |
+
Produces (scale, shift, gate) for each sub-layer from a shared condition vector.
|
| 324 |
+
"""
|
| 325 |
+
def __init__(self, dim: int, num_modulations: int = 6):
|
| 326 |
+
super().__init__()
|
| 327 |
+
self.silu = nn.SiLU()
|
| 328 |
+
self.linear = nn.Linear(dim, num_modulations * dim)
|
| 329 |
+
self.num_modulations = num_modulations
|
| 330 |
+
nn.init.zeros_(self.linear.weight)
|
| 331 |
+
nn.init.zeros_(self.linear.bias)
|
| 332 |
+
|
| 333 |
+
def forward(self, c: torch.Tensor) -> Tuple[torch.Tensor, ...]:
|
| 334 |
+
"""c: [B, D] condition vector → tuple of num_modulations tensors [B, D]."""
|
| 335 |
+
params = self.linear(self.silu(c))
|
| 336 |
+
return params.chunk(self.num_modulations, dim=-1)
|
| 337 |
+
|
| 338 |
+
|
| 339 |
+
# ============================================================================
|
| 340 |
+
# GRFM: Gated Recurrent Fourier Mixer (Novel Contribution)
|
| 341 |
+
# ============================================================================
|
| 342 |
+
|
| 343 |
+
class FourierMixingPathway(nn.Module):
|
| 344 |
+
"""Pathway 1: Adaptive Fourier Neural Operator-style global mixing.
|
| 345 |
+
O(N log N) complexity via FFT. Block-diagonal MLP in frequency domain.
|
| 346 |
+
"""
|
| 347 |
+
def __init__(self, dim: int, num_blocks: int = 8, sparsity_threshold: float = 0.01):
|
| 348 |
+
super().__init__()
|
| 349 |
+
self.dim = dim
|
| 350 |
+
self.num_blocks = num_blocks
|
| 351 |
+
self.block_size = dim // num_blocks
|
| 352 |
+
self.sparsity_threshold = sparsity_threshold
|
| 353 |
+
|
| 354 |
+
# Block-diagonal complex-valued MLP in Fourier domain
|
| 355 |
+
# Each block: R^{block_size} → R^{block_size}
|
| 356 |
+
# Using real-valued params for complex ops (split real/imag)
|
| 357 |
+
self.w1_real = nn.Parameter(torch.randn(num_blocks, self.block_size, self.block_size) * 0.02)
|
| 358 |
+
self.w1_imag = nn.Parameter(torch.randn(num_blocks, self.block_size, self.block_size) * 0.02)
|
| 359 |
+
self.w2_real = nn.Parameter(torch.randn(num_blocks, self.block_size, self.block_size) * 0.02)
|
| 360 |
+
self.w2_imag = nn.Parameter(torch.randn(num_blocks, self.block_size, self.block_size) * 0.02)
|
| 361 |
+
self.b1 = nn.Parameter(torch.zeros(num_blocks, self.block_size))
|
| 362 |
+
self.b2 = nn.Parameter(torch.zeros(num_blocks, self.block_size))
|
| 363 |
+
|
| 364 |
+
def complex_matmul(self, x: torch.Tensor, w_real: torch.Tensor, w_imag: torch.Tensor) -> torch.Tensor:
|
| 365 |
+
"""Complex matrix multiplication: (a+bi)(c+di) = (ac-bd) + (ad+bc)i
|
| 366 |
+
x: [..., num_blocks, block_size] (complex)
|
| 367 |
+
w: [num_blocks, block_size, block_size] (real)
|
| 368 |
+
"""
|
| 369 |
+
# Use einsum for proper block-diagonal matmul
|
| 370 |
+
# x: [B, Hf, Wf, K, bs], w: [K, bs, bs] → out: [B, Hf, Wf, K, bs]
|
| 371 |
+
out_real = torch.einsum('...ki,kij->...kj', x.real, w_real) - torch.einsum('...ki,kij->...kj', x.imag, w_imag)
|
| 372 |
+
out_imag = torch.einsum('...ki,kij->...kj', x.real, w_imag) + torch.einsum('...ki,kij->...kj', x.imag, w_real)
|
| 373 |
+
return torch.complex(out_real, out_imag)
|
| 374 |
+
|
| 375 |
+
def forward(self, x: torch.Tensor, H: int, W: int) -> torch.Tensor:
|
| 376 |
+
B, N, D = x.shape
|
| 377 |
+
x_2d = x.reshape(B, H, W, D)
|
| 378 |
+
|
| 379 |
+
# 2D Real FFT on spatial dimensions
|
| 380 |
+
x_freq = torch.fft.rfft2(x_2d, dim=(1, 2), norm='ortho') # [B, H, W//2+1, D]
|
| 381 |
+
|
| 382 |
+
# Reshape channel dim for block-diagonal MLP: D → (num_blocks, block_size)
|
| 383 |
+
Hf, Wf = x_freq.shape[1], x_freq.shape[2]
|
| 384 |
+
x_freq = x_freq.reshape(B, Hf, Wf, self.num_blocks, self.block_size)
|
| 385 |
+
|
| 386 |
+
# Block MLP Layer 1: operates on last dim (block_size)
|
| 387 |
+
# x_freq: [B, Hf, Wf, num_blocks, block_size]
|
| 388 |
+
# w1: [num_blocks, block_size, block_size]
|
| 389 |
+
x_freq = self.complex_matmul(x_freq, self.w1_real, self.w1_imag)
|
| 390 |
+
x_freq = x_freq + self.b1 # Broadcast bias (real only)
|
| 391 |
+
x_freq = torch.complex(F.relu(x_freq.real), F.relu(x_freq.imag))
|
| 392 |
+
|
| 393 |
+
# Block MLP Layer 2
|
| 394 |
+
x_freq = self.complex_matmul(x_freq, self.w2_real, self.w2_imag)
|
| 395 |
+
x_freq = x_freq + self.b2
|
| 396 |
+
|
| 397 |
+
# Reshape back to [B, Hf, Wf, D]
|
| 398 |
+
x_freq = x_freq.reshape(B, Hf, Wf, D)
|
| 399 |
+
|
| 400 |
+
# Soft-shrinkage (sparsity in Fourier domain)
|
| 401 |
+
magnitude = x_freq.abs()
|
| 402 |
+
shrunk_mag = F.relu(magnitude - self.sparsity_threshold)
|
| 403 |
+
# Preserve phase, shrink magnitude
|
| 404 |
+
x_freq = x_freq * (shrunk_mag / (magnitude + 1e-8))
|
| 405 |
+
|
| 406 |
+
# Inverse FFT
|
| 407 |
+
x_out = torch.fft.irfft2(x_freq, s=(H, W), dim=(1, 2), norm='ortho')
|
| 408 |
+
return x_out.reshape(B, N, D)
|
| 409 |
+
|
| 410 |
+
|
| 411 |
+
class GatedLinearRecurrence(nn.Module):
|
| 412 |
+
"""Pathway 2: Bidirectional Gated Linear Recurrence (RG-LRU inspired).
|
| 413 |
+
O(N) complexity with O(1) state per position.
|
| 414 |
+
|
| 415 |
+
h_t = a_t * h_{t-1} + sqrt(1 - a_t^2) * (i_t * x_t)
|
| 416 |
+
where a_t = sigmoid(Λ)^(c * sigmoid(W_a * x_t))
|
| 417 |
+
"""
|
| 418 |
+
def __init__(self, dim: int, recurrence_dim: int):
|
| 419 |
+
super().__init__()
|
| 420 |
+
self.dim = dim
|
| 421 |
+
self.rec_dim = recurrence_dim
|
| 422 |
+
|
| 423 |
+
# Project to recurrence space
|
| 424 |
+
self.proj_in = nn.Linear(dim, recurrence_dim * 2) # Forward + backward
|
| 425 |
+
|
| 426 |
+
# Gating parameters
|
| 427 |
+
self.W_a = nn.Linear(recurrence_dim, recurrence_dim, bias=False)
|
| 428 |
+
self.W_x = nn.Linear(recurrence_dim, recurrence_dim, bias=False)
|
| 429 |
+
self.Lambda = nn.Parameter(torch.randn(recurrence_dim) * 0.5 + 2.0) # Init for decay ~0.88-0.95
|
| 430 |
+
self.c = 8.0 # Decay scaling constant (from Griffin)
|
| 431 |
+
|
| 432 |
+
# Output projection
|
| 433 |
+
self.proj_out = nn.Linear(recurrence_dim * 2, dim)
|
| 434 |
+
|
| 435 |
+
def _scan(self, x: torch.Tensor) -> torch.Tensor:
|
| 436 |
+
"""Sequential scan for a single direction. x: [B, N, rec_dim]"""
|
| 437 |
+
B, N, D = x.shape
|
| 438 |
+
|
| 439 |
+
# Compute gates (can be parallelized)
|
| 440 |
+
a_base = torch.sigmoid(self.Lambda) # [D]
|
| 441 |
+
r = torch.sigmoid(self.W_a(x)) # [B, N, D] - recurrence gate
|
| 442 |
+
i = torch.sigmoid(self.W_x(x)) # [B, N, D] - input gate
|
| 443 |
+
|
| 444 |
+
# a_t = a_base^(c * r_t) — data-dependent decay
|
| 445 |
+
a = a_base.pow(self.c * r) # [B, N, D]
|
| 446 |
+
|
| 447 |
+
# Normalized input: sqrt(1 - a^2) for variance preservation
|
| 448 |
+
input_scale = torch.sqrt(1.0 - a * a + 1e-8)
|
| 449 |
+
scaled_input = input_scale * (i * x) # [B, N, D]
|
| 450 |
+
|
| 451 |
+
# Sequential recurrence (use parallel scan in production)
|
| 452 |
+
outputs = []
|
| 453 |
+
h = torch.zeros(B, D, device=x.device, dtype=x.dtype)
|
| 454 |
+
for t in range(N):
|
| 455 |
+
h = a[:, t] * h + scaled_input[:, t]
|
| 456 |
+
outputs.append(h)
|
| 457 |
+
|
| 458 |
+
return torch.stack(outputs, dim=1) # [B, N, D]
|
| 459 |
+
|
| 460 |
+
def forward(self, x: torch.Tensor) -> torch.Tensor:
|
| 461 |
+
B, N, D = x.shape
|
| 462 |
+
|
| 463 |
+
# Project to recurrence space and split for bidirectional
|
| 464 |
+
x_proj = self.proj_in(x) # [B, N, 2*rec_dim]
|
| 465 |
+
x_fwd, x_bwd = x_proj.chunk(2, dim=-1)
|
| 466 |
+
|
| 467 |
+
# Forward and backward scans
|
| 468 |
+
h_fwd = self._scan(x_fwd)
|
| 469 |
+
h_bwd = self._scan(x_bwd.flip(1)).flip(1)
|
| 470 |
+
|
| 471 |
+
# Merge bidirectional
|
| 472 |
+
h = torch.cat([h_fwd, h_bwd], dim=-1)
|
| 473 |
+
return self.proj_out(h)
|
| 474 |
+
|
| 475 |
+
|
| 476 |
+
class ManhattanSpatialGate(nn.Module):
|
| 477 |
+
"""Pathway 3: Manhattan distance spatial decay gating.
|
| 478 |
+
Provides learned 2D spatial inductive bias with per-head multi-scale receptive fields.
|
| 479 |
+
Uses windowed computation for efficiency.
|
| 480 |
+
"""
|
| 481 |
+
def __init__(self, dim: int, num_heads: int, window: int = 16):
|
| 482 |
+
super().__init__()
|
| 483 |
+
self.dim = dim
|
| 484 |
+
self.num_heads = num_heads
|
| 485 |
+
self.head_dim = dim // num_heads
|
| 486 |
+
self.window = window
|
| 487 |
+
|
| 488 |
+
# Per-head learnable decay rate
|
| 489 |
+
# Initialize so gamma ∈ [0.7, 0.95] — multi-scale
|
| 490 |
+
self.gamma_logit = nn.Parameter(torch.linspace(0.85, 2.94, num_heads)) # sigmoid → [0.7, 0.95]
|
| 491 |
+
|
| 492 |
+
# Value and gate projections
|
| 493 |
+
self.v_proj = nn.Linear(dim, dim)
|
| 494 |
+
self.g_proj = nn.Linear(dim, dim)
|
| 495 |
+
self.o_proj = nn.Linear(dim, dim)
|
| 496 |
+
|
| 497 |
+
def _get_manhattan_mask(self, H: int, W: int, device: torch.device) -> torch.Tensor:
|
| 498 |
+
"""Compute Manhattan distance matrix between all 2D positions."""
|
| 499 |
+
coords = torch.stack(torch.meshgrid(
|
| 500 |
+
torch.arange(H, device=device),
|
| 501 |
+
torch.arange(W, device=device),
|
| 502 |
+
indexing='ij'
|
| 503 |
+
), dim=-1).reshape(-1, 2).float() # [N, 2]
|
| 504 |
+
|
| 505 |
+
# Manhattan distance: |x1-x2| + |y1-y2|
|
| 506 |
+
dist = torch.cdist(coords, coords, p=1) # [N, N]
|
| 507 |
+
return dist
|
| 508 |
+
|
| 509 |
+
def forward(self, x: torch.Tensor, H: int, W: int) -> torch.Tensor:
|
| 510 |
+
B, N, D = x.shape
|
| 511 |
+
|
| 512 |
+
# Compute spatial decay
|
| 513 |
+
gamma = torch.sigmoid(self.gamma_logit) # [num_heads]
|
| 514 |
+
manhattan_dist = self._get_manhattan_mask(H, W, x.device) # [N, N]
|
| 515 |
+
|
| 516 |
+
# Window the distance matrix for efficiency
|
| 517 |
+
# Only compute decay for positions within window distance
|
| 518 |
+
decay_mask = (manhattan_dist <= self.window).float()
|
| 519 |
+
|
| 520 |
+
# Per-head decay: gamma_h^dist
|
| 521 |
+
decay = gamma[:, None, None].pow(manhattan_dist[None, :, :]) # [heads, N, N]
|
| 522 |
+
decay = decay * decay_mask[None, :, :]
|
| 523 |
+
|
| 524 |
+
# Value and gate
|
| 525 |
+
v = self.v_proj(x).reshape(B, N, self.num_heads, self.head_dim)
|
| 526 |
+
g = torch.sigmoid(self.g_proj(x))
|
| 527 |
+
|
| 528 |
+
# Apply spatial decay to values
|
| 529 |
+
# [B, heads, N, head_dim] = [heads, N, N] @ [B, heads, N, head_dim]
|
| 530 |
+
v = v.permute(0, 2, 1, 3) # [B, heads, N, head_dim]
|
| 531 |
+
out = torch.matmul(decay.unsqueeze(0), v) # [B, heads, N, head_dim]
|
| 532 |
+
|
| 533 |
+
# Normalize by decay sum
|
| 534 |
+
decay_sum = decay.sum(dim=-1, keepdim=True).unsqueeze(0) + 1e-8 # [1, heads, N, 1]
|
| 535 |
+
out = out / decay_sum
|
| 536 |
+
|
| 537 |
+
out = out.permute(0, 2, 1, 3).reshape(B, N, D) # [B, N, D]
|
| 538 |
+
out = out * g # Gating
|
| 539 |
+
return self.o_proj(out)
|
| 540 |
+
|
| 541 |
+
|
| 542 |
+
class GRFM(nn.Module):
|
| 543 |
+
"""Gated Recurrent Fourier Mixer — the core innovation of IRIS.
|
| 544 |
+
|
| 545 |
+
Fuses three complementary pathways:
|
| 546 |
+
1. Fourier Global Mixing (O(N log N)) — captures textures, patterns
|
| 547 |
+
2. Gated Linear Recurrence (O(N)) — captures sequential/local dependencies
|
| 548 |
+
3. Manhattan Spatial Gate — provides 2D inductive bias
|
| 549 |
+
|
| 550 |
+
Pathways are combined via learned adaptive gating.
|
| 551 |
+
"""
|
| 552 |
+
def __init__(self, config: IRISConfig):
|
| 553 |
+
super().__init__()
|
| 554 |
+
D = config.hidden_dim
|
| 555 |
+
|
| 556 |
+
self.fourier = FourierMixingPathway(D, config.fourier_num_blocks, config.sparsity_threshold)
|
| 557 |
+
self.recurrence = GatedLinearRecurrence(D, config.recurrence_dim)
|
| 558 |
+
self.spatial = ManhattanSpatialGate(D, config.num_heads, config.manhattan_window)
|
| 559 |
+
|
| 560 |
+
# Adaptive gate: learns to blend Fourier vs Recurrence based on content
|
| 561 |
+
self.blend_gate = nn.Sequential(
|
| 562 |
+
nn.Linear(D, D),
|
| 563 |
+
nn.SiLU(),
|
| 564 |
+
nn.Linear(D, D),
|
| 565 |
+
nn.Sigmoid(),
|
| 566 |
+
)
|
| 567 |
+
|
| 568 |
+
# Spatial pathway weight (smaller contribution, additive)
|
| 569 |
+
self.spatial_scale = nn.Parameter(torch.tensor(0.1))
|
| 570 |
+
|
| 571 |
+
def forward(self, x: torch.Tensor, H: int, W: int) -> torch.Tensor:
|
| 572 |
+
# Three pathways
|
| 573 |
+
x_fourier = self.fourier(x, H, W)
|
| 574 |
+
x_recurrent = self.recurrence(x)
|
| 575 |
+
x_spatial = self.spatial(x, H, W)
|
| 576 |
+
|
| 577 |
+
# Adaptive blending
|
| 578 |
+
gate = self.blend_gate(x) # [B, N, D] values in [0, 1]
|
| 579 |
+
|
| 580 |
+
# Fourier for global structure, recurrence for local detail
|
| 581 |
+
output = gate * x_fourier + (1 - gate) * x_recurrent
|
| 582 |
+
|
| 583 |
+
# Add spatial bias (small contribution)
|
| 584 |
+
output = output + self.spatial_scale * x_spatial
|
| 585 |
+
|
| 586 |
+
return output
|
| 587 |
+
|
| 588 |
+
|
| 589 |
+
# ============================================================================
|
| 590 |
+
# Cross-Attention (for text conditioning)
|
| 591 |
+
# ============================================================================
|
| 592 |
+
|
| 593 |
+
class CrossAttention(nn.Module):
|
| 594 |
+
"""Efficient cross-attention for text conditioning.
|
| 595 |
+
Only 77 text tokens → O(N × 77 × d) per layer, very cheap.
|
| 596 |
+
"""
|
| 597 |
+
def __init__(self, dim: int, text_dim: int, num_heads: int, head_dim: int):
|
| 598 |
+
super().__init__()
|
| 599 |
+
self.num_heads = num_heads
|
| 600 |
+
self.head_dim = head_dim
|
| 601 |
+
self.scale = head_dim ** -0.5
|
| 602 |
+
|
| 603 |
+
self.q_proj = nn.Linear(dim, num_heads * head_dim, bias=False)
|
| 604 |
+
self.k_proj = nn.Linear(text_dim, num_heads * head_dim, bias=False)
|
| 605 |
+
self.v_proj = nn.Linear(text_dim, num_heads * head_dim, bias=False)
|
| 606 |
+
self.o_proj = nn.Linear(num_heads * head_dim, dim)
|
| 607 |
+
|
| 608 |
+
# QK normalization for stability (from SANA-Sprint)
|
| 609 |
+
self.q_norm = nn.RMSNorm(head_dim)
|
| 610 |
+
self.k_norm = nn.RMSNorm(head_dim)
|
| 611 |
+
|
| 612 |
+
def forward(self, x: torch.Tensor, context: torch.Tensor) -> torch.Tensor:
|
| 613 |
+
B, N, _ = x.shape
|
| 614 |
+
_, S, _ = context.shape
|
| 615 |
+
|
| 616 |
+
q = self.q_proj(x).reshape(B, N, self.num_heads, self.head_dim).transpose(1, 2)
|
| 617 |
+
k = self.k_proj(context).reshape(B, S, self.num_heads, self.head_dim).transpose(1, 2)
|
| 618 |
+
v = self.v_proj(context).reshape(B, S, self.num_heads, self.head_dim).transpose(1, 2)
|
| 619 |
+
|
| 620 |
+
# QK normalization
|
| 621 |
+
q = self.q_norm(q)
|
| 622 |
+
k = self.k_norm(k)
|
| 623 |
+
|
| 624 |
+
# Scaled dot-product attention
|
| 625 |
+
attn = torch.matmul(q, k.transpose(-2, -1)) * self.scale
|
| 626 |
+
attn = F.softmax(attn, dim=-1)
|
| 627 |
+
out = torch.matmul(attn, v)
|
| 628 |
+
|
| 629 |
+
out = out.transpose(1, 2).reshape(B, N, -1)
|
| 630 |
+
return self.o_proj(out)
|
| 631 |
+
|
| 632 |
+
|
| 633 |
+
# ============================================================================
|
| 634 |
+
# Feed-Forward Network (SwiGLU)
|
| 635 |
+
# ============================================================================
|
| 636 |
+
|
| 637 |
+
class SwiGLUFFN(nn.Module):
|
| 638 |
+
"""SwiGLU Feed-Forward Network — better than GELU for transformers."""
|
| 639 |
+
def __init__(self, dim: int, ratio: float = 2.667, dropout: float = 0.0):
|
| 640 |
+
super().__init__()
|
| 641 |
+
hidden = int(dim * ratio)
|
| 642 |
+
# Ensure hidden is multiple of 64 for hardware efficiency
|
| 643 |
+
hidden = ((hidden + 63) // 64) * 64
|
| 644 |
+
|
| 645 |
+
self.w1 = nn.Linear(dim, hidden, bias=False)
|
| 646 |
+
self.w2 = nn.Linear(dim, hidden, bias=False) # Gate
|
| 647 |
+
self.w3 = nn.Linear(hidden, dim, bias=False)
|
| 648 |
+
self.dropout = nn.Dropout(dropout)
|
| 649 |
+
|
| 650 |
+
def forward(self, x: torch.Tensor) -> torch.Tensor:
|
| 651 |
+
return self.w3(self.dropout(F.silu(self.w1(x)) * self.w2(x)))
|
| 652 |
+
|
| 653 |
+
|
| 654 |
+
# ============================================================================
|
| 655 |
+
# Prelude Block (unique weights, conv-based)
|
| 656 |
+
# ============================================================================
|
| 657 |
+
|
| 658 |
+
class PreludeBlock(nn.Module):
|
| 659 |
+
"""Lightweight conv-based block for initial feature extraction."""
|
| 660 |
+
def __init__(self, dim: int):
|
| 661 |
+
super().__init__()
|
| 662 |
+
self.norm1 = nn.LayerNorm(dim)
|
| 663 |
+
self.dwconv = nn.Conv1d(dim, dim, kernel_size=5, padding=2, groups=dim)
|
| 664 |
+
self.pointwise = nn.Linear(dim, dim)
|
| 665 |
+
self.norm2 = nn.LayerNorm(dim)
|
| 666 |
+
self.ffn = SwiGLUFFN(dim)
|
| 667 |
+
|
| 668 |
+
def forward(self, x: torch.Tensor) -> torch.Tensor:
|
| 669 |
+
# Depthwise conv path
|
| 670 |
+
h = self.norm1(x)
|
| 671 |
+
h = h.transpose(1, 2) # [B, D, N]
|
| 672 |
+
h = self.dwconv(h).transpose(1, 2) # [B, N, D]
|
| 673 |
+
h = F.silu(h)
|
| 674 |
+
h = self.pointwise(h)
|
| 675 |
+
x = x + h
|
| 676 |
+
|
| 677 |
+
# FFN
|
| 678 |
+
x = x + self.ffn(self.norm2(x))
|
| 679 |
+
return x
|
| 680 |
+
|
| 681 |
+
|
| 682 |
+
# ============================================================================
|
| 683 |
+
# Core Block (shared weights, the heart of IRIS)
|
| 684 |
+
# ============================================================================
|
| 685 |
+
|
| 686 |
+
class CoreLayer(nn.Module):
|
| 687 |
+
"""Single layer within the core block.
|
| 688 |
+
Contains: GRFM + Cross-Attention + FFN, all with adaLN-Zero conditioning.
|
| 689 |
+
"""
|
| 690 |
+
def __init__(self, config: IRISConfig):
|
| 691 |
+
super().__init__()
|
| 692 |
+
D = config.hidden_dim
|
| 693 |
+
|
| 694 |
+
# Sub-layer 1: GRFM
|
| 695 |
+
self.norm1 = nn.LayerNorm(D, elementwise_affine=False)
|
| 696 |
+
self.grfm = GRFM(config)
|
| 697 |
+
|
| 698 |
+
# Sub-layer 2: Cross-Attention
|
| 699 |
+
self.norm2 = nn.LayerNorm(D, elementwise_affine=False)
|
| 700 |
+
self.cross_attn = CrossAttention(D, config.text_dim, config.num_heads, config.head_dim)
|
| 701 |
+
|
| 702 |
+
# Sub-layer 3: FFN
|
| 703 |
+
self.norm3 = nn.LayerNorm(D, elementwise_affine=False)
|
| 704 |
+
self.ffn = SwiGLUFFN(D, config.ffn_ratio, config.dropout)
|
| 705 |
+
|
| 706 |
+
# adaLN-Zero: 9 modulations (scale1, shift1, gate1, scale2, shift2, gate2, scale3, shift3, gate3)
|
| 707 |
+
self.adaln = AdaLNSingle(D, num_modulations=9)
|
| 708 |
+
|
| 709 |
+
def _modulate(self, x: torch.Tensor, scale: torch.Tensor, shift: torch.Tensor) -> torch.Tensor:
|
| 710 |
+
return x * (1 + scale.unsqueeze(1)) + shift.unsqueeze(1)
|
| 711 |
+
|
| 712 |
+
def forward(self, x: torch.Tensor, c: torch.Tensor, text_tokens: torch.Tensor,
|
| 713 |
+
H: int, W: int) -> torch.Tensor:
|
| 714 |
+
"""
|
| 715 |
+
x: [B, N, D] — token sequence
|
| 716 |
+
c: [B, D] — conditioning vector (timestep + iteration)
|
| 717 |
+
text_tokens: [B, S, text_dim] — CLIP text tokens
|
| 718 |
+
H, W: spatial dimensions of token grid
|
| 719 |
+
"""
|
| 720 |
+
s1, sh1, g1, s2, sh2, g2, s3, sh3, g3 = self.adaln(c)
|
| 721 |
+
|
| 722 |
+
# GRFM with adaLN-Zero
|
| 723 |
+
h = self._modulate(self.norm1(x), s1, sh1)
|
| 724 |
+
h = self.grfm(h, H, W)
|
| 725 |
+
x = x + g1.unsqueeze(1) * h
|
| 726 |
+
|
| 727 |
+
# Cross-attention with adaLN-Zero
|
| 728 |
+
h = self._modulate(self.norm2(x), s2, sh2)
|
| 729 |
+
h = self.cross_attn(h, text_tokens)
|
| 730 |
+
x = x + g2.unsqueeze(1) * h
|
| 731 |
+
|
| 732 |
+
# FFN with adaLN-Zero
|
| 733 |
+
h = self._modulate(self.norm3(x), s3, sh3)
|
| 734 |
+
h = self.ffn(h)
|
| 735 |
+
x = x + g3.unsqueeze(1) * h
|
| 736 |
+
|
| 737 |
+
return x
|
| 738 |
+
|
| 739 |
+
|
| 740 |
+
class CoreBlock(nn.Module):
|
| 741 |
+
"""The shared-weight core block, iterated r times.
|
| 742 |
+
Contains multiple CoreLayers to give sufficient per-iteration capacity.
|
| 743 |
+
"""
|
| 744 |
+
def __init__(self, config: IRISConfig):
|
| 745 |
+
super().__init__()
|
| 746 |
+
self.layers = nn.ModuleList([
|
| 747 |
+
CoreLayer(config) for _ in range(config.num_core_layers)
|
| 748 |
+
])
|
| 749 |
+
|
| 750 |
+
def forward(self, x: torch.Tensor, c: torch.Tensor, text_tokens: torch.Tensor,
|
| 751 |
+
H: int, W: int) -> torch.Tensor:
|
| 752 |
+
for layer in self.layers:
|
| 753 |
+
x = layer(x, c, text_tokens, H, W)
|
| 754 |
+
return x
|
| 755 |
+
|
| 756 |
+
|
| 757 |
+
# ============================================================================
|
| 758 |
+
# Coda Block (unique weights, final refinement)
|
| 759 |
+
# ============================================================================
|
| 760 |
+
|
| 761 |
+
class LocalWindowAttention(nn.Module):
|
| 762 |
+
"""Window-based local attention for final refinement.
|
| 763 |
+
Small window (8×8) for efficient local detail refinement.
|
| 764 |
+
"""
|
| 765 |
+
def __init__(self, dim: int, num_heads: int, head_dim: int, window_size: int = 8):
|
| 766 |
+
super().__init__()
|
| 767 |
+
self.num_heads = num_heads
|
| 768 |
+
self.head_dim = head_dim
|
| 769 |
+
self.window_size = window_size
|
| 770 |
+
self.scale = head_dim ** -0.5
|
| 771 |
+
|
| 772 |
+
self.qkv = nn.Linear(dim, 3 * num_heads * head_dim, bias=False)
|
| 773 |
+
self.o_proj = nn.Linear(num_heads * head_dim, dim)
|
| 774 |
+
|
| 775 |
+
def forward(self, x: torch.Tensor, H: int, W: int) -> torch.Tensor:
|
| 776 |
+
B, N, D = x.shape
|
| 777 |
+
ws = self.window_size
|
| 778 |
+
|
| 779 |
+
# Reshape to 2D and partition into windows
|
| 780 |
+
x_2d = x.reshape(B, H, W, D)
|
| 781 |
+
|
| 782 |
+
# Pad if necessary
|
| 783 |
+
pad_h = (ws - H % ws) % ws
|
| 784 |
+
pad_w = (ws - W % ws) % ws
|
| 785 |
+
if pad_h > 0 or pad_w > 0:
|
| 786 |
+
x_2d = F.pad(x_2d, (0, 0, 0, pad_w, 0, pad_h))
|
| 787 |
+
|
| 788 |
+
Hp, Wp = x_2d.shape[1], x_2d.shape[2]
|
| 789 |
+
nH, nW = Hp // ws, Wp // ws
|
| 790 |
+
|
| 791 |
+
# [B, nH, ws, nW, ws, D] → [B*nH*nW, ws*ws, D]
|
| 792 |
+
x_win = x_2d.reshape(B, nH, ws, nW, ws, D)
|
| 793 |
+
x_win = x_win.permute(0, 1, 3, 2, 4, 5).reshape(-1, ws * ws, D)
|
| 794 |
+
|
| 795 |
+
# QKV and attention within windows
|
| 796 |
+
qkv = self.qkv(x_win).reshape(-1, ws * ws, 3, self.num_heads, self.head_dim)
|
| 797 |
+
q, k, v = qkv.unbind(2)
|
| 798 |
+
q = q.transpose(1, 2)
|
| 799 |
+
k = k.transpose(1, 2)
|
| 800 |
+
v = v.transpose(1, 2)
|
| 801 |
+
|
| 802 |
+
attn = torch.matmul(q, k.transpose(-2, -1)) * self.scale
|
| 803 |
+
attn = F.softmax(attn, dim=-1)
|
| 804 |
+
out = torch.matmul(attn, v)
|
| 805 |
+
|
| 806 |
+
out = out.transpose(1, 2).reshape(-1, ws * ws, self.num_heads * self.head_dim)
|
| 807 |
+
out = self.o_proj(out)
|
| 808 |
+
|
| 809 |
+
# Unpartition
|
| 810 |
+
out = out.reshape(B, nH, nW, ws, ws, D)
|
| 811 |
+
out = out.permute(0, 1, 3, 2, 4, 5).reshape(B, Hp, Wp, D)
|
| 812 |
+
|
| 813 |
+
# Remove padding
|
| 814 |
+
out = out[:, :H, :W, :].reshape(B, N, D)
|
| 815 |
+
return out
|
| 816 |
+
|
| 817 |
+
|
| 818 |
+
class CodaBlock(nn.Module):
|
| 819 |
+
"""Final refinement block with local window attention."""
|
| 820 |
+
def __init__(self, config: IRISConfig):
|
| 821 |
+
super().__init__()
|
| 822 |
+
D = config.hidden_dim
|
| 823 |
+
self.norm1 = nn.LayerNorm(D)
|
| 824 |
+
self.attn = LocalWindowAttention(D, config.num_heads, config.head_dim, window_size=8)
|
| 825 |
+
self.norm2 = nn.LayerNorm(D)
|
| 826 |
+
self.ffn = SwiGLUFFN(D, config.ffn_ratio)
|
| 827 |
+
|
| 828 |
+
def forward(self, x: torch.Tensor, H: int, W: int) -> torch.Tensor:
|
| 829 |
+
x = x + self.attn(self.norm1(x), H, W)
|
| 830 |
+
x = x + self.ffn(self.norm2(x))
|
| 831 |
+
return x
|
| 832 |
+
|
| 833 |
+
|
| 834 |
+
# ============================================================================
|
| 835 |
+
# IRIS Generator (Main Model)
|
| 836 |
+
# ============================================================================
|
| 837 |
+
|
| 838 |
+
class IRISGenerator(nn.Module):
|
| 839 |
+
"""
|
| 840 |
+
IRIS: Iterative Recurrent Image Synthesis
|
| 841 |
+
|
| 842 |
+
The main denoising network with Prelude-Core-Coda structure.
|
| 843 |
+
Predicts velocity field v for rectified flow training.
|
| 844 |
+
"""
|
| 845 |
+
def __init__(self, config: IRISConfig):
|
| 846 |
+
super().__init__()
|
| 847 |
+
self.config = config
|
| 848 |
+
D = config.hidden_dim
|
| 849 |
+
|
| 850 |
+
# Patch embedding: latent patches → tokens
|
| 851 |
+
self.patch_embed = nn.Linear(config.patch_dim, D)
|
| 852 |
+
|
| 853 |
+
# Positional embedding (learned)
|
| 854 |
+
self.pos_embed = nn.Parameter(torch.randn(1, config.num_patches, D) * 0.02)
|
| 855 |
+
|
| 856 |
+
# Conditioning
|
| 857 |
+
self.time_embed = TimestepEmbedding(D)
|
| 858 |
+
self.iter_embed = IterationEmbedding(config.max_iterations, D)
|
| 859 |
+
self.text_proj = nn.Linear(config.text_dim, D) # Project CLIP text to model dim
|
| 860 |
+
|
| 861 |
+
# Global text pooling for conditioning
|
| 862 |
+
self.text_pool_proj = nn.Sequential(
|
| 863 |
+
nn.Linear(config.text_dim, D),
|
| 864 |
+
nn.SiLU(),
|
| 865 |
+
nn.Linear(D, D),
|
| 866 |
+
)
|
| 867 |
+
|
| 868 |
+
# Prelude (unique weights)
|
| 869 |
+
self.prelude = nn.ModuleList([PreludeBlock(D) for _ in range(config.num_prelude_blocks)])
|
| 870 |
+
|
| 871 |
+
# Core (shared weights, iterated)
|
| 872 |
+
self.core = CoreBlock(config)
|
| 873 |
+
|
| 874 |
+
# Long skip connection (from Diffusion-RWKV: linear(cat(shallow, deep)))
|
| 875 |
+
self.skip_proj = nn.Linear(2 * D, D)
|
| 876 |
+
|
| 877 |
+
# Coda (unique weights)
|
| 878 |
+
self.coda = nn.ModuleList([CodaBlock(config) for _ in range(config.num_coda_blocks)])
|
| 879 |
+
|
| 880 |
+
# Output projection: tokens → latent patches
|
| 881 |
+
self.final_norm = nn.LayerNorm(D)
|
| 882 |
+
self.output_proj = nn.Linear(D, config.patch_dim)
|
| 883 |
+
|
| 884 |
+
# Zero-init output for stable training start
|
| 885 |
+
nn.init.zeros_(self.output_proj.weight)
|
| 886 |
+
nn.init.zeros_(self.output_proj.bias)
|
| 887 |
+
|
| 888 |
+
# Precompute patch spatial dimensions
|
| 889 |
+
self.patch_h = config.latent_spatial // config.patch_size
|
| 890 |
+
self.patch_w = config.latent_spatial // config.patch_size
|
| 891 |
+
|
| 892 |
+
def patchify(self, z: torch.Tensor) -> torch.Tensor:
|
| 893 |
+
"""Convert latent z [B, C, H, W] → patches [B, N, patch_dim]."""
|
| 894 |
+
B, C, H, W = z.shape
|
| 895 |
+
p = self.config.patch_size
|
| 896 |
+
z = z.reshape(B, C, H // p, p, W // p, p)
|
| 897 |
+
z = z.permute(0, 2, 4, 1, 3, 5).reshape(B, -1, C * p * p)
|
| 898 |
+
return z
|
| 899 |
+
|
| 900 |
+
def unpatchify(self, x: torch.Tensor) -> torch.Tensor:
|
| 901 |
+
"""Convert patches [B, N, patch_dim] → latent [B, C, H, W]."""
|
| 902 |
+
B, N, _ = x.shape
|
| 903 |
+
p = self.config.patch_size
|
| 904 |
+
C = self.config.latent_channels
|
| 905 |
+
H = self.patch_h
|
| 906 |
+
W = self.patch_w
|
| 907 |
+
x = x.reshape(B, H, W, C, p, p)
|
| 908 |
+
x = x.permute(0, 3, 1, 4, 2, 5).reshape(B, C, H * p, W * p)
|
| 909 |
+
return x
|
| 910 |
+
|
| 911 |
+
def forward(
|
| 912 |
+
self,
|
| 913 |
+
z_t: torch.Tensor, # Noisy latent [B, C, H, W]
|
| 914 |
+
t: torch.Tensor, # Timestep [B] in [0, 1]
|
| 915 |
+
text_tokens: torch.Tensor, # CLIP text embeddings [B, S, text_dim]
|
| 916 |
+
num_iterations: Optional[int] = None, # Override iteration count
|
| 917 |
+
) -> torch.Tensor:
|
| 918 |
+
"""Predict velocity field v(z_t, t, c) for rectified flow."""
|
| 919 |
+
B = z_t.shape[0]
|
| 920 |
+
r = num_iterations or self.config.default_iterations
|
| 921 |
+
H, W = self.patch_h, self.patch_w
|
| 922 |
+
|
| 923 |
+
# Patchify and embed
|
| 924 |
+
x = self.patch_embed(self.patchify(z_t)) + self.pos_embed
|
| 925 |
+
|
| 926 |
+
# Timestep conditioning
|
| 927 |
+
t_emb = self.time_embed(t * self.config.num_timesteps) # [B, D]
|
| 928 |
+
|
| 929 |
+
# Text conditioning (project to model dim for cross-attention)
|
| 930 |
+
text_projected = self.text_proj(text_tokens) # [B, S, D]
|
| 931 |
+
|
| 932 |
+
# Global text pool for adaLN conditioning
|
| 933 |
+
text_global = self.text_pool_proj(text_tokens.mean(dim=1)) # [B, D]
|
| 934 |
+
|
| 935 |
+
# ============ PRELUDE ============
|
| 936 |
+
for block in self.prelude:
|
| 937 |
+
x = block(x)
|
| 938 |
+
|
| 939 |
+
# Save for long skip connection
|
| 940 |
+
x_shallow = x
|
| 941 |
+
|
| 942 |
+
# ============ CORE (iterated r times) ============
|
| 943 |
+
for i in range(r):
|
| 944 |
+
# Iteration-aware conditioning
|
| 945 |
+
iter_idx = torch.full((B,), i, device=z_t.device, dtype=torch.long)
|
| 946 |
+
i_emb = self.iter_embed(iter_idx) # [B, D]
|
| 947 |
+
|
| 948 |
+
# Combined conditioning: timestep + iteration + text global
|
| 949 |
+
c = t_emb + i_emb + text_global # [B, D]
|
| 950 |
+
|
| 951 |
+
# Apply shared core block (pass original text_tokens for cross-attention)
|
| 952 |
+
x = self.core(x, c, text_tokens, H, W)
|
| 953 |
+
|
| 954 |
+
# Long skip connection (from Diffusion-RWKV paper)
|
| 955 |
+
x = self.skip_proj(torch.cat([x_shallow, x], dim=-1))
|
| 956 |
+
|
| 957 |
+
# ============ CODA ============
|
| 958 |
+
for block in self.coda:
|
| 959 |
+
x = block(x, H, W)
|
| 960 |
+
|
| 961 |
+
# Output projection
|
| 962 |
+
x = self.final_norm(x)
|
| 963 |
+
x = self.output_proj(x)
|
| 964 |
+
|
| 965 |
+
# Unpatchify to latent shape
|
| 966 |
+
v_pred = self.unpatchify(x)
|
| 967 |
+
return v_pred
|
| 968 |
+
|
| 969 |
+
|
| 970 |
+
# ============================================================================
|
| 971 |
+
# Full IRIS System
|
| 972 |
+
# ============================================================================
|
| 973 |
+
|
| 974 |
+
class IRIS(nn.Module):
|
| 975 |
+
"""Complete IRIS system: VAE + Generator.
|
| 976 |
+
|
| 977 |
+
For training: use train_step() which handles noise scheduling.
|
| 978 |
+
For inference: use generate() which runs the full pipeline.
|
| 979 |
+
"""
|
| 980 |
+
def __init__(self, config: IRISConfig):
|
| 981 |
+
super().__init__()
|
| 982 |
+
self.config = config
|
| 983 |
+
self.vae = WaveletVAE(config)
|
| 984 |
+
self.generator = IRISGenerator(config)
|
| 985 |
+
|
| 986 |
+
def encode(self, images: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
|
| 987 |
+
"""Encode images to latent space."""
|
| 988 |
+
return self.vae.encode(images)
|
| 989 |
+
|
| 990 |
+
def decode(self, z: torch.Tensor) -> torch.Tensor:
|
| 991 |
+
"""Decode latent to images."""
|
| 992 |
+
return self.vae.decode(z)
|
| 993 |
+
|
| 994 |
+
def get_velocity_target(self, z_0: torch.Tensor, noise: torch.Tensor) -> torch.Tensor:
|
| 995 |
+
"""Rectified flow velocity target: v = noise - z_0."""
|
| 996 |
+
return noise - z_0
|
| 997 |
+
|
| 998 |
+
def add_noise(self, z_0: torch.Tensor, noise: torch.Tensor, t: torch.Tensor) -> torch.Tensor:
|
| 999 |
+
"""Rectified flow forward process: z_t = (1-t)*z_0 + t*noise."""
|
| 1000 |
+
t_expand = t[:, None, None, None]
|
| 1001 |
+
return (1 - t_expand) * z_0 + t_expand * noise
|
| 1002 |
+
|
| 1003 |
+
def sample_timesteps(self, batch_size: int, device: torch.device) -> torch.Tensor:
|
| 1004 |
+
"""Sample timesteps from logit-normal distribution (from SD3/RF).
|
| 1005 |
+
Concentrates sampling on intermediate timesteps where learning is hardest.
|
| 1006 |
+
"""
|
| 1007 |
+
u = torch.randn(batch_size, device=device)
|
| 1008 |
+
t = torch.sigmoid(u) # Logit-normal with mean=0, std=1
|
| 1009 |
+
# Clamp to avoid t=0 and t=1
|
| 1010 |
+
t = t.clamp(1e-5, 1 - 1e-5)
|
| 1011 |
+
return t
|
| 1012 |
+
|
| 1013 |
+
def train_step(
|
| 1014 |
+
self,
|
| 1015 |
+
images: torch.Tensor,
|
| 1016 |
+
text_tokens: torch.Tensor,
|
| 1017 |
+
num_iterations: Optional[int] = None,
|
| 1018 |
+
) -> dict:
|
| 1019 |
+
"""Single training step for rectified flow.
|
| 1020 |
+
|
| 1021 |
+
Returns dict with loss and diagnostics.
|
| 1022 |
+
"""
|
| 1023 |
+
B = images.shape[0]
|
| 1024 |
+
device = images.device
|
| 1025 |
+
|
| 1026 |
+
# Encode to latent
|
| 1027 |
+
z_0, mean, logvar = self.encode(images)
|
| 1028 |
+
|
| 1029 |
+
# Sample noise and timesteps
|
| 1030 |
+
noise = torch.randn_like(z_0)
|
| 1031 |
+
t = self.sample_timesteps(B, device)
|
| 1032 |
+
|
| 1033 |
+
# Create noisy latent
|
| 1034 |
+
z_t = self.add_noise(z_0, noise, t)
|
| 1035 |
+
|
| 1036 |
+
# Predict velocity
|
| 1037 |
+
# Randomly sample iteration count for training robustness
|
| 1038 |
+
if num_iterations is None:
|
| 1039 |
+
r_choices = [4, 6, 8, 10, 12]
|
| 1040 |
+
r = r_choices[torch.randint(0, len(r_choices), (1,)).item()]
|
| 1041 |
+
else:
|
| 1042 |
+
r = num_iterations
|
| 1043 |
+
|
| 1044 |
+
v_pred = self.generator(z_t, t, text_tokens, num_iterations=r)
|
| 1045 |
+
v_target = self.get_velocity_target(z_0, noise)
|
| 1046 |
+
|
| 1047 |
+
# SNR-weighted loss (from Rectified Flow paper)
|
| 1048 |
+
# w(t) = t / (1 - t) — emphasizes high-noise timesteps
|
| 1049 |
+
w = t / (1 - t + 1e-8)
|
| 1050 |
+
w = w[:, None, None, None]
|
| 1051 |
+
|
| 1052 |
+
# Velocity matching loss
|
| 1053 |
+
velocity_loss = (w * (v_pred - v_target).pow(2)).mean()
|
| 1054 |
+
|
| 1055 |
+
# VAE KL loss
|
| 1056 |
+
kl_loss = -0.5 * (1 + logvar - mean.pow(2) - logvar.exp()).mean()
|
| 1057 |
+
|
| 1058 |
+
return {
|
| 1059 |
+
'loss': velocity_loss + 0.001 * kl_loss,
|
| 1060 |
+
'velocity_loss': velocity_loss.item(),
|
| 1061 |
+
'kl_loss': kl_loss.item(),
|
| 1062 |
+
'mean_t': t.mean().item(),
|
| 1063 |
+
}
|
| 1064 |
+
|
| 1065 |
+
@torch.no_grad()
|
| 1066 |
+
def generate(
|
| 1067 |
+
self,
|
| 1068 |
+
text_tokens: torch.Tensor,
|
| 1069 |
+
num_steps: int = 4,
|
| 1070 |
+
num_iterations: int = 8,
|
| 1071 |
+
cfg_scale: float = 4.0,
|
| 1072 |
+
seed: Optional[int] = None,
|
| 1073 |
+
) -> torch.Tensor:
|
| 1074 |
+
"""Generate images from text conditioning using Euler solver.
|
| 1075 |
+
|
| 1076 |
+
Args:
|
| 1077 |
+
text_tokens: [B, S, text_dim] CLIP text embeddings
|
| 1078 |
+
num_steps: Number of ODE solver steps (1-50)
|
| 1079 |
+
num_iterations: Core iterations per step (quality budget)
|
| 1080 |
+
cfg_scale: Classifier-free guidance scale
|
| 1081 |
+
seed: Random seed for reproducibility
|
| 1082 |
+
"""
|
| 1083 |
+
B, S, _ = text_tokens.shape
|
| 1084 |
+
device = text_tokens.device
|
| 1085 |
+
|
| 1086 |
+
if seed is not None:
|
| 1087 |
+
torch.manual_seed(seed)
|
| 1088 |
+
|
| 1089 |
+
# Start from pure noise
|
| 1090 |
+
z = torch.randn(B, self.config.latent_channels,
|
| 1091 |
+
self.config.latent_spatial, self.config.latent_spatial,
|
| 1092 |
+
device=device)
|
| 1093 |
+
|
| 1094 |
+
# Euler solver for rectified flow ODE: dz/dt = -v(z, t)
|
| 1095 |
+
# Integrate from t=1 (noise) to t=0 (data)
|
| 1096 |
+
dt = 1.0 / num_steps
|
| 1097 |
+
|
| 1098 |
+
for step in range(num_steps):
|
| 1099 |
+
t_val = 1.0 - step * dt
|
| 1100 |
+
t = torch.full((B,), t_val, device=device)
|
| 1101 |
+
|
| 1102 |
+
# Predict velocity
|
| 1103 |
+
v = self.generator(z, t, text_tokens, num_iterations=num_iterations)
|
| 1104 |
+
|
| 1105 |
+
# Classifier-free guidance (if cfg_scale > 1)
|
| 1106 |
+
if cfg_scale > 1.0:
|
| 1107 |
+
null_tokens = torch.zeros_like(text_tokens)
|
| 1108 |
+
v_uncond = self.generator(z, t, null_tokens, num_iterations=num_iterations)
|
| 1109 |
+
v = v_uncond + cfg_scale * (v - v_uncond)
|
| 1110 |
+
|
| 1111 |
+
# Euler step: z = z - dt * v
|
| 1112 |
+
z = z - dt * v
|
| 1113 |
+
|
| 1114 |
+
# Decode to image
|
| 1115 |
+
images = self.decode(z)
|
| 1116 |
+
images = images.clamp(-1, 1)
|
| 1117 |
+
return images
|
| 1118 |
+
|
| 1119 |
+
|
| 1120 |
+
# ============================================================================
|
| 1121 |
+
# Utility Functions
|
| 1122 |
+
# ============================================================================
|
| 1123 |
+
|
| 1124 |
+
def count_parameters(model: nn.Module) -> dict:
|
| 1125 |
+
"""Count parameters in each component."""
|
| 1126 |
+
counts = {}
|
| 1127 |
+
total = 0
|
| 1128 |
+
for name, module in model.named_children():
|
| 1129 |
+
n = sum(p.numel() for p in module.parameters())
|
| 1130 |
+
counts[name] = n
|
| 1131 |
+
total += n
|
| 1132 |
+
counts['total'] = total
|
| 1133 |
+
|
| 1134 |
+
# Separate trainable vs frozen
|
| 1135 |
+
trainable = sum(p.numel() for p in model.parameters() if p.requires_grad)
|
| 1136 |
+
counts['trainable'] = trainable
|
| 1137 |
+
return counts
|
| 1138 |
+
|
| 1139 |
+
|
| 1140 |
+
def estimate_memory_mb(model: nn.Module, dtype=torch.float16) -> float:
|
| 1141 |
+
"""Estimate model memory in MB."""
|
| 1142 |
+
bytes_per_param = 2 if dtype == torch.float16 else 4
|
| 1143 |
+
total_params = sum(p.numel() for p in model.parameters())
|
| 1144 |
+
return total_params * bytes_per_param / (1024 * 1024)
|
| 1145 |
+
|
| 1146 |
+
|
| 1147 |
+
def create_iris_small(latent_spatial: int = 32) -> IRIS:
|
| 1148 |
+
"""Create IRIS-Small: ~75M generator params, suitable for mobile."""
|
| 1149 |
+
config = IRISConfig(
|
| 1150 |
+
latent_channels=16,
|
| 1151 |
+
latent_spatial=latent_spatial,
|
| 1152 |
+
hidden_dim=512,
|
| 1153 |
+
num_heads=8,
|
| 1154 |
+
head_dim=64,
|
| 1155 |
+
ffn_ratio=2.667,
|
| 1156 |
+
num_prelude_blocks=2,
|
| 1157 |
+
num_core_layers=4,
|
| 1158 |
+
num_coda_blocks=2,
|
| 1159 |
+
default_iterations=8,
|
| 1160 |
+
max_iterations=16,
|
| 1161 |
+
fourier_num_blocks=8,
|
| 1162 |
+
sparsity_threshold=0.01,
|
| 1163 |
+
recurrence_dim=256,
|
| 1164 |
+
manhattan_window=16,
|
| 1165 |
+
text_dim=768,
|
| 1166 |
+
max_text_tokens=77,
|
| 1167 |
+
patch_size=2,
|
| 1168 |
+
)
|
| 1169 |
+
return IRIS(config)
|
| 1170 |
+
|
| 1171 |
+
|
| 1172 |
+
def create_iris_tiny(latent_spatial: int = 32) -> IRIS:
|
| 1173 |
+
"""Create IRIS-Tiny: ~30M generator params, ultra-mobile."""
|
| 1174 |
+
config = IRISConfig(
|
| 1175 |
+
latent_channels=8,
|
| 1176 |
+
latent_spatial=latent_spatial,
|
| 1177 |
+
hidden_dim=384,
|
| 1178 |
+
num_heads=6,
|
| 1179 |
+
head_dim=64,
|
| 1180 |
+
ffn_ratio=2.667,
|
| 1181 |
+
num_prelude_blocks=1,
|
| 1182 |
+
num_core_layers=3,
|
| 1183 |
+
num_coda_blocks=1,
|
| 1184 |
+
default_iterations=8,
|
| 1185 |
+
max_iterations=16,
|
| 1186 |
+
fourier_num_blocks=6,
|
| 1187 |
+
sparsity_threshold=0.01,
|
| 1188 |
+
recurrence_dim=192,
|
| 1189 |
+
manhattan_window=12,
|
| 1190 |
+
text_dim=768,
|
| 1191 |
+
max_text_tokens=77,
|
| 1192 |
+
patch_size=2,
|
| 1193 |
+
)
|
| 1194 |
+
return IRIS(config)
|
| 1195 |
+
|
| 1196 |
+
|
| 1197 |
+
def create_iris_base(latent_spatial: int = 32) -> IRIS:
|
| 1198 |
+
"""Create IRIS-Base: ~150M generator params, quality-focused."""
|
| 1199 |
+
config = IRISConfig(
|
| 1200 |
+
latent_channels=16,
|
| 1201 |
+
latent_spatial=latent_spatial,
|
| 1202 |
+
hidden_dim=768,
|
| 1203 |
+
num_heads=12,
|
| 1204 |
+
head_dim=64,
|
| 1205 |
+
ffn_ratio=2.667,
|
| 1206 |
+
num_prelude_blocks=2,
|
| 1207 |
+
num_core_layers=6,
|
| 1208 |
+
num_coda_blocks=2,
|
| 1209 |
+
default_iterations=8,
|
| 1210 |
+
max_iterations=16,
|
| 1211 |
+
fourier_num_blocks=12,
|
| 1212 |
+
sparsity_threshold=0.01,
|
| 1213 |
+
recurrence_dim=384,
|
| 1214 |
+
manhattan_window=16,
|
| 1215 |
+
text_dim=768,
|
| 1216 |
+
max_text_tokens=77,
|
| 1217 |
+
patch_size=2,
|
| 1218 |
+
)
|
| 1219 |
+
return IRIS(config)
|
| 1220 |
+
|
| 1221 |
+
|
| 1222 |
+
if __name__ == "__main__":
|
| 1223 |
+
print("=" * 70)
|
| 1224 |
+
print("IRIS: Iterative Recurrent Image Synthesis")
|
| 1225 |
+
print("=" * 70)
|
| 1226 |
+
|
| 1227 |
+
# Create model variants
|
| 1228 |
+
for name, create_fn in [("IRIS-Tiny", create_iris_tiny),
|
| 1229 |
+
("IRIS-Small", create_iris_small),
|
| 1230 |
+
("IRIS-Base", create_iris_base)]:
|
| 1231 |
+
print(f"\n{'─' * 50}")
|
| 1232 |
+
print(f" {name}")
|
| 1233 |
+
print(f"{'─' * 50}")
|
| 1234 |
+
model = create_fn()
|
| 1235 |
+
counts = count_parameters(model)
|
| 1236 |
+
mem_fp16 = estimate_memory_mb(model, torch.float16)
|
| 1237 |
+
mem_fp32 = estimate_memory_mb(model, torch.float32)
|
| 1238 |
+
|
| 1239 |
+
print(f" Total params: {counts['total']:>12,}")
|
| 1240 |
+
print(f" Trainable params: {counts['trainable']:>12,}")
|
| 1241 |
+
print(f" Memory (fp16): {mem_fp16:>10.1f} MB")
|
| 1242 |
+
print(f" Memory (fp32): {mem_fp32:>10.1f} MB")
|
| 1243 |
+
print(f" Components:")
|
| 1244 |
+
for k, v in counts.items():
|
| 1245 |
+
if k not in ('total', 'trainable'):
|
| 1246 |
+
print(f" {k:20s}: {v:>10,} ({v/counts['total']*100:.1f}%)")
|