diff --git a/configs/gaitssb/pretrain.yaml b/configs/gaitssb/pretrain.yaml
new file mode 100644
index 0000000..b948749
--- /dev/null
+++ b/configs/gaitssb/pretrain.yaml
@@ -0,0 +1,93 @@
+data_cfg:
+  dataset_name: GaitLU-1M
+  dataset_root: /your/path/to/GaitLU-1M
+  dataset_partition: ./datasets/GaitLU-1M/GaitLU-1M.json
+  num_workers: 1
+  remove_no_gallery: false # Remove probe if no gallery for it
+
+evaluator_cfg:
+  enable_float16: true
+  restore_ckpt_strict: true
+  restore_hint: 150000
+  save_name: GaitSSB_Pretrain
+  sampler:
+    batch_shuffle: false
+    batch_size: 16
+    sample_type: all_ordered # all indicates whole sequence used to test, while ordered means input sequence by its natural order; Other options:   fixed_unordered
+    frames_all_limit: 720 # limit the number of sampled frames to prevent out of memory
+  metric: euc # cos
+  transform:
+    - type: BaseSilTransform
+
+loss_cfg:
+  - loss_term_weight: 1.0
+    scale: 16
+    type: CrossEntropyLoss
+    log_prefix: softmax1
+    log_accuracy: true
+  - loss_term_weight: 1.0
+    scale: 16
+    type: CrossEntropyLoss
+    log_prefix: softmax2
+    log_accuracy: true
+
+model_cfg:
+  model: GaitSSB_Pretrain
+  backbone_cfg:
+    type: ResNet9
+    block: BasicBlock
+    channels: # Layers configuration for automatically model construction
+      - 64
+      - 128
+      - 256
+      - 512
+    layers:
+      - 1
+      - 1
+      - 1
+      - 1
+    strides:
+      - 1
+      - 2
+      - 2
+      - 1
+    maxpool: false
+  parts_num: 31
+
+optimizer_cfg:
+  lr: 0.05
+  momentum: 0.9
+  solver: SGD
+  weight_decay: 0.0005
+  # weight_decay: 0.
+
+scheduler_cfg:
+  gamma: 0.1
+  milestones: # Learning Rate Reduction at each milestones
+    - 80000
+    - 120000
+  scheduler: MultiStepLR
+
+trainer_cfg:
+  enable_float16: true # half_percesion float for memory reduction and speedup
+  fix_BN: false
+  with_test: false
+  log_iter: 100
+  restore_ckpt_strict: true
+  restore_hint: 0
+  save_iter: 10000
+  save_name: GaitSSB_Pretrain
+  sync_BN: true
+  total_iter: 150000
+  sampler:
+    batch_shuffle: true
+    batch_size:
+      - 8  # TripletSampler, batch_size[0] indicates Number of Identity
+      - 64 # batch_size[1] indicates Samples sequqnce for each Identity
+    frames_num_fixed: 16 # fixed frames number for training
+    sample_type: fixed_ordered # fixed control input frames number, unordered for controlling order of input tensor; Other options: unfixed_ordered or all_ordered
+    frames_skip_num: 4
+    type: BilateralSampler
+  transform:
+    - type: DA4GaitSSB
+      cutting: 10
diff --git a/datasets/GaitLU-1M/GaitLU-1M.json b/datasets/GaitLU-1M/GaitLU-1M.json
new file mode 100644
index 0000000..1e089c6
--- /dev/null
+++ b/datasets/GaitLU-1M/GaitLU-1M.json
@@ -0,0 +1,105 @@
+{
+    "TRAIN_SET": [
+        "000",
+        "001",
+        "002",
+        "003",
+        "004",
+        "005",
+        "006",
+        "007",
+        "008",
+        "009",
+        "010",
+        "011",
+        "012",
+        "013",
+        "014",
+        "015",
+        "016",
+        "017",
+        "018",
+        "019",
+        "020",
+        "021",
+        "022",
+        "023",
+        "024",
+        "025",
+        "026",
+        "027",
+        "028",
+        "029",
+        "030",
+        "031",
+        "032",
+        "033",
+        "034",
+        "035",
+        "036",
+        "037",
+        "038",
+        "039",
+        "040",
+        "041",
+        "042",
+        "043",
+        "044",
+        "045",
+        "046",
+        "047",
+        "048",
+        "049",
+        "050",
+        "051",
+        "052",
+        "053",
+        "054",
+        "055",
+        "056",
+        "057",
+        "058",
+        "059",
+        "060",
+        "061",
+        "062",
+        "063",
+        "064",
+        "065",
+        "066",
+        "067",
+        "068",
+        "069",
+        "070",
+        "071",
+        "072",
+        "073",
+        "074",
+        "075",
+        "076",
+        "077",
+        "078",
+        "079",
+        "080",
+        "081",
+        "082",
+        "083",
+        "084",
+        "085",
+        "086",
+        "087",
+        "088",
+        "089",
+        "090",
+        "091",
+        "092",
+        "093",
+        "094",
+        "095",
+        "096",
+        "097",
+        "098",
+        "099"
+    ],
+    "TEST_SET": []
+}
diff --git a/opengait/data/sampler.py b/opengait/data/sampler.py
index 605e0f9..ec58073 100644
--- a/opengait/data/sampler.py
+++ b/opengait/data/sampler.py
@@ -134,3 +134,41 @@ class CommonSampler(tordata.sampler.Sampler):
 
     def __len__(self):
         return len(self.dataset)
+
+# **************** For GaitSSB ****************
+# Fan, et al: Learning Gait Representation from Massive Unlabelled Walking Videos: A Benchmark, T-PAMI2023
+import random
+class BilateralSampler(tordata.sampler.Sampler):
+    def __init__(self, dataset, batch_size, batch_shuffle=False):
+        self.dataset = dataset
+        self.batch_size = batch_size
+        self.batch_shuffle = batch_shuffle
+
+        self.world_size = dist.get_world_size()
+        self.rank = dist.get_rank()
+
+        self.dataset_length = len(self.dataset)
+        self.total_indices = list(range(self.dataset_length))
+
+    def __iter__(self):
+        random.shuffle(self.total_indices)
+        count = 0
+        batch_size = self.batch_size[0] * self.batch_size[1]
+        while True:
+            if (count + 1) * batch_size >= self.dataset_length:
+                count = 0
+                random.shuffle(self.total_indices)
+
+            sampled_indices = self.total_indices[count*batch_size:(count+1)*batch_size]
+            sampled_indices = sync_random_sample_list(sampled_indices, len(sampled_indices))
+
+            total_size = int(math.ceil(batch_size / self.world_size)) * self.world_size
+            sampled_indices += sampled_indices[:(batch_size - len(sampled_indices))]
+
+            sampled_indices = sampled_indices[self.rank:total_size:self.world_size]
+            count += 1
+
+            yield sampled_indices * 2
+
+    def __len__(self):
+        return len(self.dataset)
\ No newline at end of file
diff --git a/opengait/data/transform.py b/opengait/data/transform.py
index 73f92d8..3c8162a 100644
--- a/opengait/data/transform.py
+++ b/opengait/data/transform.py
@@ -35,7 +35,8 @@ class BaseParsingCuttingTransform():
             cutting = self.cutting
         else:
             cutting = int(x.shape[-1] // 64) * 10
-        x = x[..., cutting:-cutting]
+        if cutting != 0: 
+            x = x[..., cutting:-cutting]
         if x.max() == 255 or x.max() == 255.:
             return x / self.divsor
         else:
@@ -52,7 +53,8 @@ class BaseSilCuttingTransform():
             cutting = self.cutting
         else:
             cutting = int(x.shape[-1] // 64) * 10
-        x = x[..., cutting:-cutting]
+        if cutting != 0: 
+            x = x[..., cutting:-cutting]
         return x / self.divsor
 
 
@@ -214,8 +216,115 @@ def get_transform(trf_cfg=None):
         return transform
     raise "Error type for -Transform-Cfg-"
 
+# **************** For GaitSSB ****************
+# Fan, et al: Learning Gait Representation from Massive Unlabelled Walking Videos: A Benchmark, T-PAMI2023
 
-# **************** For pose ****************
+class RandomPartDilate():
+    def __init__(self, prob=0.5, top_range=(12, 16), bot_range=(36, 40)):
+        self.prob = prob
+        self.top_range = top_range
+        self.bot_range = bot_range
+        self.modes_and_kernels = {
+            'RECT': [[5, 3], [5, 5], [3, 5]],
+            'CROSS': [[3, 3], [3, 5], [5, 3]],
+            'ELLIPSE': [[3, 3], [3, 5], [5, 3]]}
+        self.modes = list(self.modes_and_kernels.keys())
+
+    def __call__(self, seq):
+        '''
+            Using the image dialte and affine transformation to simulate the clorhing change cases.
+        Input:
+            seq: a sequence of silhouette frames, [s, h, w]
+        Output:
+            seq: a sequence of agumented frames, [s, h, w]
+        '''
+        if random.uniform(0, 1) >= self.prob:
+                return seq
+        else:
+            mode = random.choice(self.modes)
+            kernel_size = random.choice(self.modes_and_kernels[mode])
+            top = random.randint(self.top_range[0], self.top_range[1])
+            bot = random.randint(self.bot_range[0], self.bot_range[1])
+
+            seq = seq.transpose(1, 2, 0) # [s, h, w] -> [h, w, s]
+            _seq_ = seq.copy()
+            _seq_ = _seq_[top:bot, ...]
+            _seq_ = self.dilate(_seq_, kernel_size=kernel_size, mode=mode)
+            seq[top:bot, ...] = _seq_
+            seq = seq.transpose(2, 0, 1) # [h, w, s] -> [s, h, w]
+            return seq
+
+    def dilate(self, img, kernel_size=[3, 3], mode='RECT'):
+        '''
+            MORPH_RECT, MORPH_CROSS, ELLIPSE
+        Input:
+            img: [h, w]
+        Output:
+            img: [h, w]
+        '''
+        assert mode in ['RECT', 'CROSS', 'ELLIPSE']
+        kernel = cv2.getStructuringElement(getattr(cv2, 'MORPH_'+mode), kernel_size)
+        dst = cv2.dilate(img, kernel)
+        return dst
+
+class RandomPartBlur():
+    def __init__(self, prob=0.5, top_range=(9, 20), bot_range=(29, 40), per_frame=False):
+        self.prob = prob
+        self.top_range = top_range
+        self.bot_range = bot_range
+        self.per_frame = per_frame
+
+    def __call__(self, seq):
+        '''
+        Input:
+            seq: a sequence of silhouette frames, [s, h, w]
+        Output:
+            seq: a sequence of agumented frames, [s, h, w]
+        '''
+        if not self.per_frame:
+            if random.uniform(0, 1) >= self.prob:
+                return seq
+            else:
+                top = random.randint(self.top_range[0], self.top_range[1])
+                bot = random.randint(self.bot_range[0], self.bot_range[1])
+
+                seq = seq.transpose(1, 2, 0) # [s, h, w] -> [h, w, s]
+                _seq_ = seq.copy()
+                _seq_ = _seq_[top:bot, ...]
+                _seq_ = cv2.GaussianBlur(_seq_, ksize=(3, 3), sigmaX=0)
+                _seq_ = (_seq_ > 0.2).astype(np.float)
+                seq[top:bot, ...] = _seq_
+                seq = seq.transpose(2, 0, 1) # [h, w, s] -> [s, h, w]
+
+            return seq
+        else:
+            self.per_frame = False
+            frame_num = seq.shape[0]
+            ret = [self.__call__(seq[k][np.newaxis, ...]) for k in range(frame_num)]
+            self.per_frame = True
+            return np.concatenate(ret, 0)
+
+def DA4GaitSSB(
+    cutting = None,
+    ra_prob = 0.2,
+    rp_prob = 0.2,
+    rhf_prob = 0.5,
+    rpd_prob = 0.2,
+    rpb_prob = 0.2,
+    top_range = (9, 20),
+    bot_range = (39, 50),
+):
+    transform = T.Compose([
+            RandomAffine(prob=ra_prob),
+            RandomPerspective(prob=rp_prob),
+            BaseSilCuttingTransform(cutting=cutting),
+            RandomHorizontalFlip(prob=rhf_prob),
+            RandomPartDilate(prob=rpd_prob, top_range=top_range, bot_range=bot_range),
+            RandomPartBlur(prob=rpb_prob, top_range=top_range, bot_range=bot_range),
+    ])
+    return transform
+
+# **************** For pose-based methods ****************
 class RandomSelectSequence(object):
     """
     Randomly select different subsequences
diff --git a/opengait/modeling/models/gaitssb.py b/opengait/modeling/models/gaitssb.py
new file mode 100644
index 0000000..dd0685a
--- /dev/null
+++ b/opengait/modeling/models/gaitssb.py
@@ -0,0 +1,142 @@
+import torch
+import numpy as np
+import torch.nn as nn
+import torch.optim as optim
+import torch.nn.functional as F
+
+from ..base_model import BaseModel
+from ..modules import PackSequenceWrapper, HorizontalPoolingPyramid, SetBlockWrapper, ParallelBN1d, SeparateFCs
+
+from utils import np2var, list2var, get_valid_args, ddp_all_gather
+from data.transform import get_transform
+from einops import rearrange
+
+# Modified from https://github.com/PatrickHua/SimSiam/blob/main/models/simsiam.py
+class GaitSSB_Pretrain(BaseModel):
+    def __init__(self, cfgs, training=True):
+        super(GaitSSB_Pretrain, self).__init__(cfgs, training=training)
+
+    def build_network(self, model_cfg):
+        self.p = model_cfg['parts_num']
+        self.Backbone = self.get_backbone(model_cfg['backbone_cfg'])
+        self.Backbone = SetBlockWrapper(self.Backbone)
+
+        self.TP = PackSequenceWrapper(torch.max)
+        self.HPP = HorizontalPoolingPyramid([16, 8, 4, 2, 1])
+
+        out_channels = model_cfg['backbone_cfg']['channels'][-1]
+        hidden_dim = out_channels
+        self.projector = nn.Sequential(SeparateFCs(self.p, out_channels, hidden_dim),
+                                ParallelBN1d(self.p, hidden_dim),
+                                nn.ReLU(inplace=True),
+                                SeparateFCs(self.p, hidden_dim, out_channels),
+                                ParallelBN1d(self.p, out_channels))
+        self.predictor = nn.Sequential(SeparateFCs(self.p, out_channels, hidden_dim),
+                                ParallelBN1d(self.p, hidden_dim),
+                                nn.ReLU(inplace=True),
+                                SeparateFCs(self.p, hidden_dim, out_channels))
+
+    def inputs_pretreament(self, inputs):
+        if self.training:
+            seqs_batch, labs_batch, typs_batch, vies_batch, seqL_batch = inputs
+            trf_cfgs = self.engine_cfg['transform']
+            seq_trfs = get_transform(trf_cfgs)
+
+            requires_grad = True if self.training else False
+            batch_size = int(len(seqs_batch[0]) / 2)
+            img_q = [np2var(np.asarray([trf(fra) for fra in seq[:batch_size]]), requires_grad=requires_grad).float()  for trf, seq in zip(seq_trfs, seqs_batch)]
+            img_k = [np2var(np.asarray([trf(fra) for fra in seq[batch_size:]]), requires_grad=requires_grad).float()  for trf, seq in zip(seq_trfs, seqs_batch)]
+            seqs = [img_q, img_k]
+
+            typs = typs_batch
+            vies = vies_batch
+
+            if self.training:
+                labs = list2var(labs_batch).long()
+            else:
+                labs = None
+
+            if seqL_batch is not None:
+                seqL_batch = np2var(seqL_batch).int()
+            seqL = seqL_batch
+
+            ipts = seqs
+            del seqs
+
+            return ipts, labs, typs, vies, (seqL, seqL)
+        else:
+            return super().inputs_pretreament(inputs)
+
+    def encoder(self, inputs):
+        sils, seqL = inputs
+        assert sils.size(-1) in [44, 88]
+        outs = self.Backbone(sils) # [n, c, s, h, w]
+        outs = self.TP(outs, seqL, options={"dim": 2})[0] # [n, c, h, w]
+        feat = self.HPP(outs) # [n, c, p], Horizontal Pooling, HP
+        return feat
+
+    def forward(self, inputs):
+        '''
+        Input: 
+            sils_q: a batch of query images, [n, s, h, w]
+            sils_k: a batch of key images, [n, s, h, w]
+        Output:
+            logits, targets
+        '''
+        if self.training:
+            (sils_q, sils_k), labs, typs, vies, (seqL_q, seqL_k) = inputs
+
+            sils_q, sils_k = sils_q[0].unsqueeze(1), sils_k[0].unsqueeze(1)
+
+            q_input = (sils_q, seqL_q)
+            q_feat = self.encoder(q_input) # [n, c, p]
+            z1 = self.projector(q_feat)
+            p1 = self.predictor(z1)
+
+            k_input = (sils_k, seqL_k)
+            k_feat = self.encoder(k_input) # [n, c, p]
+            z2 = self.projector(k_feat)
+            p2 = self.predictor(z2)
+
+            logits1, labels1 = self.D(p1, z2)
+            logits2, labels2 = self.D(p2, z1)
+
+            retval = {
+                    'training_feat': {'softmax1': {'logits': logits1, 'labels': labels1},
+                        'softmax2': {'logits': logits2, 'labels': labels2}
+                    },
+                    'visual_summary': {'image/encoder_q': rearrange(sils_q, 'n c s h w -> (n s) c h w'),
+                        'image/encoder_k': rearrange(sils_k, 'n c s h w -> (n s) c h w'),
+                    },
+                    'inference_feat': None
+            }
+            return retval
+        else:
+            sils, labs, typs, vies, seqL = inputs
+            sils = sils[0].unsqueeze(1)
+            feat = self.encoder((sils, seqL)) # [n, c, p]
+            feat = self.projector(feat) # [n, c, p]
+            feat = self.predictor(feat) # [n, c, p]
+            retval = {
+                'training_feat': None,
+                'visual_summary': None,
+                'inference_feat': {'embeddings': F.normalize(feat, dim=1)}
+            }
+            return retval
+
+    def D(self, p, z): # negative cosine similarity
+        """
+            p: [n, c, p]
+            z: [n, c, p]
+        """
+        z = z.detach() # stop gradient
+        n = p.size(0)
+
+        p = F.normalize(p, dim=1) # l2-normalize, [n, c, p]
+        z = F.normalize(z, dim=1) # l2-normalize, [n, c, p]
+        z = ddp_all_gather(z, dim=0, requires_grad=False) # [m, c, p],  m = n * the number of GPUs
+
+        logits = torch.einsum('ncp, mcp->nmp', [p, z]) # [n, m, p]
+        rank   = torch.distributed.get_rank()
+        labels = torch.arange(rank*n, (rank+1)*n, dtype=torch.long).cuda()
+        return logits, labels
\ No newline at end of file
diff --git a/opengait/modeling/modules.py b/opengait/modeling/modules.py
index 9e40631..1cc2309 100644
--- a/opengait/modeling/modules.py
+++ b/opengait/modeling/modules.py
@@ -690,4 +690,19 @@ class SpatialAttention(nn.Module):
         batch, Nh, dv, T, V = x.size()
         ret_shape = (batch, Nh * dv, T, V)
         return torch.reshape(x, ret_shape)
-    
\ No newline at end of file
+
+from einops import rearrange
+class ParallelBN1d(nn.Module):
+    def __init__(self, parts_num, in_channels, **kwargs):
+        super(ParallelBN1d, self).__init__()
+        self.parts_num = parts_num
+        self.bn1d = nn.BatchNorm1d(in_channels * parts_num, **kwargs)
+
+    def forward(self, x):
+        '''
+            x: [n, c, p]
+        '''
+        x = rearrange(x, 'n c p -> n (c p)')
+        x = self.bn1d(x)
+        x = rearrange(x, 'n (c p) -> n c p', p=self.parts_num)
+        return x
\ No newline at end of file