jennyxue commited on
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b3a0426
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bf16 build of BiRefNet

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Files changed (3) hide show
  1. bf16/config.json +6 -0
  2. bf16/mlx_model.py +462 -0
  3. bf16/model.safetensors +3 -0
bf16/config.json ADDED
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+ {
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+ "model_type": "birefnet",
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+ "backbone": "swin_v1_l",
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+ "input_size": 1024,
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+ "precision": "bf16"
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+ }
bf16/mlx_model.py ADDED
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1
+ """BiRefNet (ZhengPeng7/BiRefNet, BiRefNet_lite; MIT) in MLX: a port of the Hub repo's `birefnet.py` for the
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+ released configuration (Swin v1 backbone run at full and half resolution and concatenated, 3 context features,
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+ ASPPDeformable decoder blocks, image-patch inputs, gradient attention).
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+
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+ import mlx_model
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+ model = mlx_model.load("bf16") # a folder with config.json + model.safetensors
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+ alpha = mlx_model.matte(model, rgb) # rgb: HxWx3 uint8 -> HxW uint8 alpha (255 = foreground)
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+
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+ Runs on its own next to its weights (mlx and numpy). NHWC throughout. Each BatchNorm is folded into the conv before
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+ it at conversion; torchvision's deform_conv2d (DCNv2, with modulation) is written out as bilinear gathers.
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+ Quantized builds (8bit / 6bit / 4bit) quantize the Swin backbone's linears whose input size is a multiple of 64;
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+ the convolutions stay bf16.
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+ """
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+
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+ from __future__ import annotations
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+
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+ import json
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+ from pathlib import Path
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+
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+ import mlx.core as mx
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+ import mlx.nn as nn
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+ import numpy as np
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+
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+ SWIN = {"swin_v1_t": dict(embed_dim=96, depths=[2, 2, 6, 2], num_heads=[3, 6, 12, 24], window_size=7),
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+ "swin_v1_l": dict(embed_dim=192, depths=[2, 2, 18, 2], num_heads=[6, 12, 24, 48], window_size=12)}
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+ CONFIG = {"model_type": "birefnet", "backbone": "swin_v1_t", "input_size": 1024}
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+ PRECISIONS = ["bf16", "fp16", "8bit", "6bit", "4bit"]
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+ MEAN, STD = np.array([0.485, 0.456, 0.406], np.float32), np.array([0.229, 0.224, 0.225], np.float32)
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+ GROUP = 64
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+
31
+
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+ def quantizable(path: str, module) -> bool:
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+ return isinstance(module, nn.Linear) and module.weight.shape[-1] % GROUP == 0
34
+
35
+
36
+ # ------------------------------------------------------------------------------------------------ ops
37
+
38
+ def resize(x, size, align_corners: bool):
39
+ """torch F.interpolate(mode="bilinear") for NHWC (no antialiasing)."""
40
+ b, h, w, c = x.shape
41
+ oh, ow = int(size[0]), int(size[1])
42
+ if (oh, ow) == (h, w):
43
+ return x
44
+
45
+ def axis(n_in, n_out):
46
+ if align_corners:
47
+ s = np.arange(n_out, dtype=np.float64) * ((n_in - 1) / (n_out - 1) if n_out > 1 else 0.0)
48
+ else:
49
+ s = np.clip((np.arange(n_out, dtype=np.float64) + 0.5) * (n_in / n_out) - 0.5, 0, None)
50
+ i0 = np.minimum(np.floor(s).astype(np.int32), n_in - 1)
51
+ i1 = np.minimum(i0 + 1, n_in - 1)
52
+ return mx.array(i0), mx.array(i1), mx.array((s - i0).astype(np.float32))
53
+
54
+ y0, y1, fy = axis(h, oh)
55
+ x0, x1, fx = axis(w, ow)
56
+ fy = fy.astype(x.dtype)[None, :, None, None]
57
+ fx = fx.astype(x.dtype)[None, None, :, None]
58
+ top, bot = x[:, y0], x[:, y1]
59
+ top = top[:, :, x0] * (1 - fx) + top[:, :, x1] * fx
60
+ bot = bot[:, :, x0] * (1 - fx) + bot[:, :, x1] * fx
61
+ return top * (1 - fy) + bot * fy
62
+
63
+
64
+ def to_patches(x, ref_hw):
65
+ """einops 'b c (hg h) (wg w) -> b (c hg wg) h w' in NHWC."""
66
+ b, H, W, c = x.shape
67
+ h, w = ref_hw
68
+ hg, wg = H // h, W // w
69
+ x = x.reshape(b, hg, h, wg, w, c).transpose(0, 2, 4, 5, 1, 3)
70
+ return x.reshape(b, h, w, c * hg * wg)
71
+
72
+
73
+ def deform_conv(x, offset, mask, weight, bias, k: int):
74
+ """torchvision.ops.deform_conv2d (stride 1, padding k // 2, dilation 1, one offset group) with a modulation mask.
75
+ x (1, H, W, C), offset (1, H, W, 2 k k) as (dy, dx) per kernel position, mask (1, H, W, k k), weight (O, k, k, C)."""
76
+ b, h, w, c = x.shape
77
+ assert b == 1, "batch 1"
78
+ pad = k // 2
79
+ flat = x.reshape(h * w, c)
80
+ gy = mx.arange(h, dtype=mx.float32)[:, None]
81
+ gx = mx.arange(w, dtype=mx.float32)[None, :]
82
+ off = offset[0].astype(mx.float32)
83
+ out = None
84
+ for i in range(k * k):
85
+ ky, kx = divmod(i, k)
86
+ py = gy + (ky - pad) + off[:, :, 2 * i]
87
+ px = gx + (kx - pad) + off[:, :, 2 * i + 1]
88
+ y0, x0 = mx.floor(py), mx.floor(px)
89
+ ly, lx = py - y0, px - x0
90
+ acc = None
91
+ for yy, xx, wt in ((y0, x0, (1 - ly) * (1 - lx)), (y0, x0 + 1, (1 - ly) * lx),
92
+ (y0 + 1, x0, ly * (1 - lx)), (y0 + 1, x0 + 1, ly * lx)):
93
+ ok = (yy >= 0) & (yy <= h - 1) & (xx >= 0) & (xx <= w - 1)
94
+ idx = (mx.clip(yy, 0, h - 1) * w + mx.clip(xx, 0, w - 1)).astype(mx.int32).reshape(-1)
95
+ v = mx.take(flat, idx, axis=0) * mx.where(ok, wt, 0.0).reshape(-1, 1).astype(x.dtype)
96
+ acc = v if acc is None else acc + v
97
+ acc = acc * mask[0, :, :, i].reshape(-1, 1)
98
+ y = acc @ weight[:, ky, kx, :].T
99
+ out = y if out is None else out + y
100
+ return (out + bias).reshape(1, h, w, -1)
101
+
102
+
103
+ # ------------------------------------------------------------------------------------------------ Swin v1
104
+
105
+ def window_partition(x, ws):
106
+ b, h, w, c = x.shape
107
+ x = x.reshape(b, h // ws, ws, w // ws, ws, c).transpose(0, 1, 3, 2, 4, 5)
108
+ return x.reshape(-1, ws * ws, c)
109
+
110
+
111
+ def window_reverse(win, ws, h, w):
112
+ c = win.shape[-1]
113
+ b = win.shape[0] // ((h // ws) * (w // ws))
114
+ x = win.reshape(b, h // ws, w // ws, ws, ws, c).transpose(0, 1, 3, 2, 4, 5)
115
+ return x.reshape(b, h, w, c)
116
+
117
+
118
+ def relative_index(ws: int) -> np.ndarray:
119
+ coords = np.stack(np.meshgrid(np.arange(ws), np.arange(ws), indexing="ij")).reshape(2, -1)
120
+ rel = (coords[:, :, None] - coords[:, None, :]).transpose(1, 2, 0) + (ws - 1)
121
+ return rel[:, :, 0] * (2 * ws - 1) + rel[:, :, 1]
122
+
123
+
124
+ def shift_mask(hp: int, wp: int, ws: int, shift: int) -> np.ndarray:
125
+ img = np.zeros((1, hp, wp, 1), np.float32)
126
+ cnt = 0
127
+ for hs in (slice(0, -ws), slice(-ws, -shift), slice(-shift, None)):
128
+ for wsl in (slice(0, -ws), slice(-ws, -shift), slice(-shift, None)):
129
+ img[:, hs, wsl, :] = cnt
130
+ cnt += 1
131
+ m = img.reshape(1, hp // ws, ws, wp // ws, ws, 1).transpose(0, 1, 3, 2, 4, 5).reshape(-1, ws * ws)
132
+ m = m[:, None, :] - m[:, :, None]
133
+ return np.where(m != 0, -100.0, 0.0).astype(np.float32)
134
+
135
+
136
+ class WindowAttention(nn.Module):
137
+ def __init__(self, dim, ws, heads):
138
+ super().__init__()
139
+ self.heads, self.scale = heads, (dim // heads) ** -0.5
140
+ self.relative_position_bias_table = mx.zeros(((2 * ws - 1) ** 2, heads))
141
+ self._index = mx.array(relative_index(ws).reshape(-1))
142
+ self.qkv = nn.Linear(dim, dim * 3)
143
+ self.proj = nn.Linear(dim, dim)
144
+
145
+ def __call__(self, x, mask=None):
146
+ b, n, c = x.shape
147
+ qkv = self.qkv(x).reshape(b, n, 3, self.heads, c // self.heads).transpose(2, 0, 3, 1, 4)
148
+ q, k, v = qkv[0] * self.scale, qkv[1], qkv[2]
149
+ bias = self.relative_position_bias_table[self._index].reshape(n, n, -1).transpose(2, 0, 1)
150
+ attn = (q @ k.transpose(0, 1, 3, 2)) + bias[None].astype(q.dtype)
151
+ if mask is not None:
152
+ nw = mask.shape[0]
153
+ attn = attn.reshape(b // nw, nw, self.heads, n, n) + mask[None, :, None].astype(q.dtype)
154
+ attn = attn.reshape(b, self.heads, n, n)
155
+ attn = mx.softmax(attn, axis=-1, precise=True)
156
+ return self.proj((attn @ v).transpose(0, 2, 1, 3).reshape(b, n, c))
157
+
158
+
159
+ class Mlp(nn.Module):
160
+ def __init__(self, dim):
161
+ super().__init__()
162
+ self.fc1, self.fc2 = nn.Linear(dim, dim * 4), nn.Linear(dim * 4, dim)
163
+
164
+ def __call__(self, x):
165
+ return self.fc2(nn.gelu(self.fc1(x)))
166
+
167
+
168
+ class SwinBlock(nn.Module):
169
+ def __init__(self, dim, heads, ws, shift):
170
+ super().__init__()
171
+ self.ws, self.shift = ws, shift
172
+ self.norm1, self.norm2 = nn.LayerNorm(dim), nn.LayerNorm(dim)
173
+ self.attn = WindowAttention(dim, ws, heads)
174
+ self.mlp = Mlp(dim)
175
+
176
+ def __call__(self, x, h, w, mask):
177
+ b, L, c = x.shape
178
+ ws, s = self.ws, self.shift
179
+ y = self.norm1(x).reshape(b, h, w, c)
180
+ pr, pb = (ws - w % ws) % ws, (ws - h % ws) % ws
181
+ if pr or pb:
182
+ y = mx.pad(y, [(0, 0), (0, pb), (0, pr), (0, 0)])
183
+ hp, wp = h + pb, w + pr
184
+ if s:
185
+ y = mx.roll(y, (-s, -s), axis=(1, 2))
186
+ y = window_reverse(self.attn(window_partition(y, ws), mask if s else None), ws, hp, wp)
187
+ if s:
188
+ y = mx.roll(y, (s, s), axis=(1, 2))
189
+ y = y[:, :h, :w].reshape(b, h * w, c)
190
+ x = x + y
191
+ return x + self.mlp(self.norm2(x))
192
+
193
+
194
+ class PatchMerging(nn.Module):
195
+ def __init__(self, dim):
196
+ super().__init__()
197
+ self.norm = nn.LayerNorm(4 * dim)
198
+ self.reduction = nn.Linear(4 * dim, 2 * dim, bias=False)
199
+
200
+ def __call__(self, x, h, w):
201
+ b, L, c = x.shape
202
+ x = x.reshape(b, h, w, c)
203
+ if h % 2 or w % 2:
204
+ x = mx.pad(x, [(0, 0), (0, h % 2), (0, w % 2), (0, 0)])
205
+ x = mx.concatenate([x[:, 0::2, 0::2], x[:, 1::2, 0::2], x[:, 0::2, 1::2], x[:, 1::2, 1::2]], -1)
206
+ return self.reduction(self.norm(x.reshape(b, -1, 4 * c)))
207
+
208
+
209
+ class SwinLayer(nn.Module):
210
+ def __init__(self, dim, depth, heads, ws, down):
211
+ super().__init__()
212
+ self.ws = ws
213
+ self.blocks = [SwinBlock(dim, heads, ws, 0 if i % 2 == 0 else ws // 2) for i in range(depth)]
214
+ if down:
215
+ self.downsample = PatchMerging(dim)
216
+ self._masks = {}
217
+
218
+ def __call__(self, x, h, w):
219
+ ws = self.ws
220
+ hp, wp = -(-h // ws) * ws, -(-w // ws) * ws
221
+ if (hp, wp) not in self._masks:
222
+ self._masks[(hp, wp)] = mx.array(shift_mask(hp, wp, ws, ws // 2))
223
+ mask = self._masks[(hp, wp)]
224
+ for blk in self.blocks:
225
+ x = blk(x, h, w, mask)
226
+ if "downsample" in self:
227
+ return x, self.downsample(x, h, w), (h + 1) // 2, (w + 1) // 2
228
+ return x, x, h, w
229
+
230
+
231
+ class PatchEmbed(nn.Module):
232
+ def __init__(self, dim):
233
+ super().__init__()
234
+ self.proj = nn.Conv2d(3, dim, 4, stride=4)
235
+ self.norm = nn.LayerNorm(dim)
236
+
237
+ def __call__(self, x):
238
+ b, h, w, _ = x.shape
239
+ if w % 4 or h % 4:
240
+ x = mx.pad(x, [(0, 0), (0, (4 - h % 4) % 4), (0, (4 - w % 4) % 4), (0, 0)])
241
+ return self.norm(self.proj(x))
242
+
243
+
244
+ class Swin(nn.Module):
245
+ def __init__(self, embed_dim, depths, num_heads, window_size):
246
+ super().__init__()
247
+ self.patch_embed = PatchEmbed(embed_dim)
248
+ self.dims = [embed_dim * 2 ** i for i in range(4)]
249
+ self.layers = [SwinLayer(self.dims[i], depths[i], num_heads[i], window_size, i < 3) for i in range(4)]
250
+ for i, d in enumerate(self.dims):
251
+ setattr(self, f"norm{i}", nn.LayerNorm(d))
252
+
253
+ def __call__(self, x):
254
+ x = self.patch_embed(x)
255
+ b, h, w, c = x.shape
256
+ x = x.reshape(b, h * w, c)
257
+ outs = []
258
+ for i, layer in enumerate(self.layers):
259
+ xo, x, nh, nw = layer(x, h, w)
260
+ outs.append(getattr(self, f"norm{i}")(xo).reshape(b, h, w, self.dims[i]))
261
+ h, w = nh, nw
262
+ return outs
263
+
264
+
265
+ # ------------------------------------------------------------------------------------------------ decoder
266
+
267
+ class DeformConv(nn.Module):
268
+ def __init__(self, cin, cout, k):
269
+ super().__init__()
270
+ self.k = k
271
+ self.offset_conv = nn.Conv2d(cin, 2 * k * k, k, padding=k // 2)
272
+ self.modulator_conv = nn.Conv2d(cin, k * k, k, padding=k // 2)
273
+ self.regular_conv = nn.Conv2d(cin, cout, k, padding=k // 2) # its weight (BatchNorm folded in)
274
+
275
+ def __call__(self, x):
276
+ off = self.offset_conv(x)
277
+ mask = 2 * mx.sigmoid(self.modulator_conv(x))
278
+ return deform_conv(x, off, mask, self.regular_conv.weight, self.regular_conv.bias, self.k)
279
+
280
+
281
+ class ASPPDeformable(nn.Module):
282
+ def __init__(self, cin, mid=256, sizes=(1, 3, 7)):
283
+ super().__init__()
284
+ self.aspp1 = DeformConv(cin, mid, 1)
285
+ self.aspp_deforms = [DeformConv(cin, mid, k) for k in sizes]
286
+ self.gap_conv = nn.Conv2d(cin, mid, 1)
287
+ self.conv1 = nn.Conv2d(mid * (2 + len(sizes)), cin, 1)
288
+
289
+ def __call__(self, x):
290
+ b, h, w, _ = x.shape
291
+ parts = [nn.relu(self.aspp1(x))] + [nn.relu(d(x)) for d in self.aspp_deforms]
292
+ g = x.astype(mx.float32).mean(axis=(1, 2), keepdims=True).astype(x.dtype) # fp16 sums overflow
293
+ g = nn.relu(self.gap_conv(g))
294
+ parts.append(mx.broadcast_to(g, (b, h, w, g.shape[-1])))
295
+ return nn.relu(self.conv1(mx.concatenate(parts, -1)))
296
+
297
+
298
+ class DecBlk(nn.Module):
299
+ def __init__(self, cin, cout, inter=64):
300
+ super().__init__()
301
+ self.conv_in = nn.Conv2d(cin, inter, 3, padding=1)
302
+ self.dec_att = ASPPDeformable(inter)
303
+ self.conv_out = nn.Conv2d(inter, cout, 3, padding=1)
304
+
305
+ def __call__(self, x):
306
+ return self.conv_out(self.dec_att(nn.relu(self.conv_in(x))))
307
+
308
+
309
+ class SimpleConvs(nn.Module):
310
+ def __init__(self, cin, cout, inter=64):
311
+ super().__init__()
312
+ self.conv1 = nn.Conv2d(cin, inter, 3, padding=1)
313
+ self.conv_out = nn.Conv2d(inter, cout, 3, padding=1)
314
+
315
+ def __call__(self, x):
316
+ return self.conv_out(self.conv1(x))
317
+
318
+
319
+ class Decoder(nn.Module):
320
+ def __init__(self, ch):
321
+ super().__init__()
322
+ self.ipt_blk5 = SimpleConvs(2 ** 10 * 3, ch[0] // 8)
323
+ self.ipt_blk4 = SimpleConvs(2 ** 8 * 3, ch[0] // 8)
324
+ self.ipt_blk3 = SimpleConvs(2 ** 6 * 3, ch[1] // 8)
325
+ self.ipt_blk2 = SimpleConvs(2 ** 4 * 3, ch[2] // 8)
326
+ self.ipt_blk1 = SimpleConvs(3, ch[3] // 8)
327
+ self.decoder_block4 = DecBlk(ch[0] + ch[0] // 8, ch[1])
328
+ self.decoder_block3 = DecBlk(ch[1] + ch[0] // 8, ch[2])
329
+ self.decoder_block2 = DecBlk(ch[2] + ch[1] // 8, ch[3])
330
+ self.decoder_block1 = DecBlk(ch[3] + ch[2] // 8, ch[3] // 2)
331
+ self.conv_out1 = nn.Conv2d(ch[3] // 2 + ch[3] // 8, 1, 1)
332
+ self.lateral_block4 = nn.Conv2d(ch[1], ch[1], 1)
333
+ self.lateral_block3 = nn.Conv2d(ch[2], ch[2], 1)
334
+ self.lateral_block2 = nn.Conv2d(ch[3], ch[3], 1)
335
+ for i, c in ((4, ch[1]), (3, ch[2]), (2, ch[3])):
336
+ setattr(self, f"gdt_convs_{i}", nn.Conv2d(c, 16, 3, padding=1))
337
+ setattr(self, f"gdt_attn_{i}", nn.Conv2d(16, 1, 1))
338
+
339
+ def gdt(self, i, p):
340
+ return p * mx.sigmoid(getattr(self, f"gdt_attn_{i}")(nn.relu(getattr(self, f"gdt_convs_{i}")(p))))
341
+
342
+ def __call__(self, x, x1, x2, x3, x4):
343
+ up = lambda a, ref: resize(a, ref.shape[1:3], True)
344
+ x4 = mx.concatenate([x4, self.ipt_blk5(to_patches(x, x4.shape[1:3]))], -1)
345
+ p4 = self.gdt(4, self.decoder_block4(x4))
346
+ p3 = up(p4, x3) + self.lateral_block4(x3)
347
+ p3 = mx.concatenate([p3, self.ipt_blk4(to_patches(x, p3.shape[1:3]))], -1)
348
+ p3 = self.gdt(3, self.decoder_block3(p3))
349
+ p2 = up(p3, x2) + self.lateral_block3(x2)
350
+ p2 = mx.concatenate([p2, self.ipt_blk3(to_patches(x, p2.shape[1:3]))], -1)
351
+ p2 = self.gdt(2, self.decoder_block2(p2))
352
+ p1 = up(p2, x1) + self.lateral_block2(x1)
353
+ p1 = mx.concatenate([p1, self.ipt_blk2(to_patches(x, p1.shape[1:3]))], -1)
354
+ p1 = up(self.decoder_block1(p1), x)
355
+ p1 = mx.concatenate([p1, self.ipt_blk1(x)], -1)
356
+ return self.conv_out1(p1)
357
+
358
+
359
+ class Model(nn.Module):
360
+ def __init__(self, config: dict = CONFIG):
361
+ super().__init__()
362
+ sw = SWIN[config["backbone"]]
363
+ self.size = config["input_size"]
364
+ self.bb = Swin(**sw)
365
+ ch = [d * 2 for d in self.bb.dims[::-1]] # mul_scl_ipt = "cat"
366
+ cxt = ch[1:][::-1]
367
+ self.squeeze_module = DecBlk(ch[0] + sum(cxt), ch[0])
368
+ self.decoder = Decoder(ch)
369
+
370
+ def __call__(self, x):
371
+ """x: (1, S, S, 3) ImageNet-normalized -> (1, S, S, 1) logits."""
372
+ b, h, w, _ = x.shape
373
+ f = self.bb(x)
374
+ g = self.bb(resize(x, (h // 2, w // 2), True))
375
+ f = [mx.concatenate([a, resize(c, a.shape[1:3], True)], -1) for a, c in zip(f, g)]
376
+ x1, x2, x3, x4 = f
377
+ x4 = mx.concatenate([resize(x1, x4.shape[1:3], True), resize(x2, x4.shape[1:3], True),
378
+ resize(x3, x4.shape[1:3], True), x4], -1)
379
+ x4 = self.squeeze_module(x4)
380
+ return self.decoder(x, x1, x2, x3, x4)
381
+
382
+
383
+ def load(folder) -> Model:
384
+ folder = Path(folder)
385
+ config = json.loads((folder / "config.json").read_text())
386
+ model = Model(config)
387
+ q = config.get("quantization")
388
+ if q:
389
+ nn.quantize(model, group_size=q["group_size"], bits=q["bits"], class_predicate=quantizable)
390
+ model.load_weights(str(folder / "model.safetensors"), strict=True)
391
+ mx.eval(model.parameters())
392
+ return model
393
+
394
+
395
+ def dtype(model: Model):
396
+ return model.decoder.conv_out1.weight.dtype
397
+
398
+
399
+ def predict(model: Model, rgb: np.ndarray) -> np.ndarray:
400
+ """HxWx3 uint8 -> HxW float32 foreground probability: resized to the model size (bilinear, as PIL in the
401
+ original handler) and back."""
402
+ from PIL import Image
403
+ h, w, _ = rgb.shape
404
+ s = model.size
405
+ x = np.asarray(Image.fromarray(rgb).resize((s, s), Image.BILINEAR), np.float32) / 255.0
406
+ x = mx.array(((x - MEAN) / STD)[None]).astype(dtype(model))
407
+ y = mx.sigmoid(model(x).astype(mx.float32))
408
+ return np.array(resize(y, (h, w), True))[0, :, :, 0]
409
+
410
+
411
+ def matte(model: Model, rgb: np.ndarray) -> np.ndarray:
412
+ return (np.clip(predict(model, rgb), 0, 1) * 255).round().astype(np.uint8)
413
+
414
+
415
+ # ------------------------------------------------------------------------------------------------ conversion
416
+
417
+ def _fold(sd, conv, bn):
418
+ w = sd[conv + ".weight"].astype(np.float64)
419
+ b = sd.get(conv + ".bias", np.zeros(w.shape[0])).astype(np.float64)
420
+ if bn is not None:
421
+ g = sd[bn + ".weight"] / np.sqrt(sd[bn + ".running_var"].astype(np.float64) + 1e-5)
422
+ w = w * g[:, None, None, None]
423
+ b = (b - sd[bn + ".running_mean"]) * g + sd[bn + ".bias"]
424
+ return w.astype(np.float32).transpose(0, 2, 3, 1), b.astype(np.float32)
425
+
426
+
427
+ def convert(source: Path) -> dict:
428
+ """runs/source/model.safetensors -> MLX names: BatchNorms folded, Sequential indices renamed, buffers and the
429
+ training-only heads (conv_ms_spvn_*, gdt_convs_pred_*) dropped."""
430
+ from safetensors.numpy import load_file
431
+ sd = load_file(str(Path(source) / "model.safetensors"))
432
+ out = {}
433
+ for k, v in sd.items():
434
+ if k.startswith("bb."):
435
+ if k.endswith("relative_position_index"):
436
+ continue
437
+ out[k] = v.transpose(0, 2, 3, 1) if v.ndim == 4 else v
438
+ blocks = sorted({k.split(".dec_att.")[0] for k in sd if ".dec_att." in k})
439
+ for blk in blocks: # decoder.decoder_blockN, squeeze_module.0
440
+ dst = "squeeze_module" if blk == "squeeze_module.0" else blk
441
+ out[dst + ".conv_in.weight"], out[dst + ".conv_in.bias"] = _fold(sd, blk + ".conv_in", blk + ".bn_in")
442
+ out[dst + ".conv_out.weight"], out[dst + ".conv_out.bias"] = _fold(sd, blk + ".conv_out", blk + ".bn_out")
443
+ a = blk + ".dec_att"
444
+ for src_m, dst_m in [(a + ".aspp1", dst + ".dec_att.aspp1")] + [
445
+ (f"{a}.aspp_deforms.{i}", f"{dst}.dec_att.aspp_deforms.{i}") for i in range(3)]:
446
+ for c in ("offset_conv", "modulator_conv"):
447
+ out[f"{dst_m}.{c}.weight"], out[f"{dst_m}.{c}.bias"] = _fold(sd, f"{src_m}.atrous_conv.{c}", None)
448
+ out[f"{dst_m}.regular_conv.weight"], out[f"{dst_m}.regular_conv.bias"] = _fold(
449
+ sd, f"{src_m}.atrous_conv.regular_conv", f"{src_m}.bn")
450
+ out[dst + ".dec_att.gap_conv.weight"], out[dst + ".dec_att.gap_conv.bias"] = _fold(
451
+ sd, a + ".global_avg_pool.1", a + ".global_avg_pool.2")
452
+ out[dst + ".dec_att.conv1.weight"], out[dst + ".dec_att.conv1.bias"] = _fold(sd, a + ".conv1", a + ".bn1")
453
+ d = "decoder."
454
+ for i in range(1, 6):
455
+ for c in ("conv1", "conv_out"):
456
+ out[f"{d}ipt_blk{i}.{c}.weight"], out[f"{d}ipt_blk{i}.{c}.bias"] = _fold(sd, f"{d}ipt_blk{i}.{c}", None)
457
+ for i in (2, 3, 4):
458
+ out[f"{d}lateral_block{i}.weight"], out[f"{d}lateral_block{i}.bias"] = _fold(sd, f"{d}lateral_block{i}.conv", None)
459
+ out[f"{d}gdt_convs_{i}.weight"], out[f"{d}gdt_convs_{i}.bias"] = _fold(sd, f"{d}gdt_convs_{i}.0", f"{d}gdt_convs_{i}.1")
460
+ out[f"{d}gdt_attn_{i}.weight"], out[f"{d}gdt_attn_{i}.bias"] = _fold(sd, f"{d}gdt_convs_attn_{i}.0", None)
461
+ out[d + "conv_out1.weight"], out[d + "conv_out1.bias"] = _fold(sd, d + "conv_out1.0", None)
462
+ return out
bf16/model.safetensors ADDED
@@ -0,0 +1,3 @@
 
 
 
 
1
+ version https://git-lfs.github.com/spec/v1
2
+ oid sha256:f8732f5d43482fcba4f347bc192292fe8a5975582383ffe2bdf71627bf4f0e0f
3
+ size 440368909