Files
StarPilot/tinygrad_repo/extra/models/vit.py
T
firestar5683 22a8575199 Vendor dependencies and resources for standalone builds
Keep official openpilot ancestry and dependency licenses. Store resources directly in Git, remove LFS setup requirements, and leave the downloadable big model outside the source tree.
2026-10-03 21:01:18 +00:00

74 lines
4.1 KiB
Python

import numpy as np
from tinygrad.tensor import Tensor
from tinygrad.helpers import fetch
from extra.models.transformer import TransformerBlock
class ViT:
def __init__(self, layers=12, embed_dim=192, num_heads=3):
self.embedding = (Tensor.uniform(embed_dim, 3, 16, 16), Tensor.zeros(embed_dim))
self.embed_dim = embed_dim
self.cls = Tensor.ones(1, 1, embed_dim)
self.pos_embedding = Tensor.ones(1, 197, embed_dim)
self.tbs = [
TransformerBlock(embed_dim=embed_dim, num_heads=num_heads, ff_dim=embed_dim*4,
prenorm=True, act=lambda x: x.gelu())
for i in range(layers)]
self.encoder_norm = (Tensor.uniform(embed_dim), Tensor.zeros(embed_dim))
self.head = (Tensor.uniform(embed_dim, 1000), Tensor.zeros(1000))
def patch_embed(self, x):
x = x.conv2d(*self.embedding, stride=16)
x = x.reshape(shape=(x.shape[0], x.shape[1], -1)).permute(order=(0,2,1))
return x
def forward(self, x):
ce = self.cls.add(Tensor.zeros(x.shape[0],1,1))
pe = self.patch_embed(x)
x = ce.cat(pe, dim=1)
x = x.add(self.pos_embedding).sequential(self.tbs)
x = x.layernorm().linear(*self.encoder_norm)
return x[:, 0].linear(*self.head)
def load_from_pretrained(m):
# https://github.com/rwightman/pytorch-image-models/blob/master/timm/models/vision_transformer.py
if m.embed_dim == 192:
url = "https://storage.googleapis.com/vit_models/augreg/Ti_16-i21k-300ep-lr_0.001-aug_none-wd_0.03-do_0.0-sd_0.0--imagenet2012-steps_20k-lr_0.03-res_224.npz"
elif m.embed_dim == 768:
url = "https://storage.googleapis.com/vit_models/augreg/B_16-i21k-300ep-lr_0.001-aug_medium1-wd_0.1-do_0.0-sd_0.0--imagenet2012-steps_20k-lr_0.01-res_224.npz"
else:
raise Exception("no pretrained weights for configuration")
dat = np.load(fetch(url))
#for x in dat.keys():
# print(x, dat[x].shape, dat[x].dtype)
m.embedding[0].assign(np.transpose(dat['embedding/kernel'], (3,2,0,1)))
m.embedding[1].assign(dat['embedding/bias'])
m.cls.assign(dat['cls'])
m.head[0].assign(dat['head/kernel'])
m.head[1].assign(dat['head/bias'])
m.pos_embedding.assign(dat['Transformer/posembed_input/pos_embedding'])
m.encoder_norm[0].assign(dat['Transformer/encoder_norm/scale'])
m.encoder_norm[1].assign(dat['Transformer/encoder_norm/bias'])
for i in range(12):
m.tbs[i].query[0].assign(dat[f'Transformer/encoderblock_{i}/MultiHeadDotProductAttention_1/query/kernel'].reshape(m.embed_dim, m.embed_dim))
m.tbs[i].query[1].assign(dat[f'Transformer/encoderblock_{i}/MultiHeadDotProductAttention_1/query/bias'].reshape(m.embed_dim))
m.tbs[i].key[0].assign(dat[f'Transformer/encoderblock_{i}/MultiHeadDotProductAttention_1/key/kernel'].reshape(m.embed_dim, m.embed_dim))
m.tbs[i].key[1].assign(dat[f'Transformer/encoderblock_{i}/MultiHeadDotProductAttention_1/key/bias'].reshape(m.embed_dim))
m.tbs[i].value[0].assign(dat[f'Transformer/encoderblock_{i}/MultiHeadDotProductAttention_1/value/kernel'].reshape(m.embed_dim, m.embed_dim))
m.tbs[i].value[1].assign(dat[f'Transformer/encoderblock_{i}/MultiHeadDotProductAttention_1/value/bias'].reshape(m.embed_dim))
m.tbs[i].out[0].assign(dat[f'Transformer/encoderblock_{i}/MultiHeadDotProductAttention_1/out/kernel'].reshape(m.embed_dim, m.embed_dim))
m.tbs[i].out[1].assign(dat[f'Transformer/encoderblock_{i}/MultiHeadDotProductAttention_1/out/bias'].reshape(m.embed_dim))
m.tbs[i].ff1[0].assign(dat[f'Transformer/encoderblock_{i}/MlpBlock_3/Dense_0/kernel'])
m.tbs[i].ff1[1].assign(dat[f'Transformer/encoderblock_{i}/MlpBlock_3/Dense_0/bias'])
m.tbs[i].ff2[0].assign(dat[f'Transformer/encoderblock_{i}/MlpBlock_3/Dense_1/kernel'])
m.tbs[i].ff2[1].assign(dat[f'Transformer/encoderblock_{i}/MlpBlock_3/Dense_1/bias'])
m.tbs[i].ln1[0].assign(dat[f'Transformer/encoderblock_{i}/LayerNorm_0/scale'])
m.tbs[i].ln1[1].assign(dat[f'Transformer/encoderblock_{i}/LayerNorm_0/bias'])
m.tbs[i].ln2[0].assign(dat[f'Transformer/encoderblock_{i}/LayerNorm_2/scale'])
m.tbs[i].ln2[1].assign(dat[f'Transformer/encoderblock_{i}/LayerNorm_2/bias'])