diff --git a/.github/workflows/sta-publish.yml b/.github/workflows/sta-publish.yml
index e7f76cecb..f442e3efd 100644
--- a/.github/workflows/sta-publish.yml
+++ b/.github/workflows/sta-publish.yml
@@ -5,7 +5,7 @@ on:
     branches:
       - main
     paths:
-      - "csrc/sliding_tile_attention/setup.py"
+      - "csrc/attn/setup_sta.py"
   workflow_dispatch:
 
 jobs:
@@ -23,13 +23,13 @@ jobs:
       - name: Check if version changed
         id: check-version
         run: |
-          cd csrc/sliding_tile_attention
+          cd csrc/attn
           # Get current commit's version
-          NEW_VERSION=$(grep -oP 'VERSION\s*=\s*"\K[^"]+' setup.py)
+          NEW_VERSION=$(grep -oP 'VERSION\s*=\s*"\K[^"]+' setup_sta.py)
           echo "New version: $NEW_VERSION"
           
           # Get previous version from git history
-          OLD_VERSION=$(git show HEAD~1:./setup.py | grep -oP 'VERSION\s*=\s*"\K[^"]+' || echo "0.0.0")
+          OLD_VERSION=$(git show HEAD~1:./setup_sta.py | grep -oP 'VERSION\s*=\s*"\K[^"]+' || echo "0.0.0")
           echo "Old version: $OLD_VERSION"
           
           if [ "$NEW_VERSION" != "$OLD_VERSION" ]; then
@@ -136,19 +136,21 @@ jobs:
 
       - name: Build wheel
         run: |
+          export PYTHONPATH=$GITHUB_WORKSPACE:$PYTHONPATH
+          
           # We want setuptools >= 49.6.0 otherwise we can't compile the extension if system CUDA version is 11.7 and pytorch cuda version is 11.6
           # https://github.com/pytorch/pytorch/blob/664058fa83f1d8eede5d66418abff6e20bd76ca8/torch/utils/cpp_extension.py#L810
           # However this still fails so I'm using a newer version of setuptools
           pip install setuptools
           pip install ninja packaging wheel
 
-          cd csrc/sliding_tile_attention  # Move into the correct folder
-          git submodule update --init --recursive tk # Ensure ThunderKittens submodule is initialized
-          python setup.py bdist_wheel --dist-dir=dist
+          cd csrc/attn  # Move into the correct folder
+          git submodule update --init --recursive # Ensure ThunderKittens submodule is initialized
+          python setup_sta.py bdist_wheel --dist-dir=dist
 
       - name: Rename wheel file
         run: |
-          cd csrc/sliding_tile_attention
+          cd csrc/attn
 
           CUDA_SHORT_VERSION=$(echo ${{ matrix.cuda-version }} | cut -d. -f1,2 | sed 's/\.//g')
           TORCH_SHORT_VERSION=$(echo ${{ matrix.torch-version }} | cut -d. -f1,2)
@@ -163,7 +165,7 @@ jobs:
         uses: actions/upload-artifact@v4
         with:
           name: ${{ env.wheel_name }}
-          path: csrc/sliding_tile_attention/dist/*.whl
+          path: csrc/attn/dist/*.whl
           retention-days: 90
 
   publish_package:
@@ -229,17 +231,19 @@ jobs:
 
       - name: Build source distribution
         run: |
+          export PYTHONPATH=$GITHUB_WORKSPACE:$PYTHONPATH
+          
           # We want setuptools >= 49.6.0 otherwise we can't compile the extension if system CUDA version is 11.7 and pytorch cuda version is 11.6
           # https://github.com/pytorch/pytorch/blob/664058fa83f1d8eede5d66418abff6e20bd76ca8/torch/utils/cpp_extension.py#L810
           # However this still fails so I'm using a newer version of setuptools
           pip install setuptools
           pip install ninja packaging wheel
 
-          cd csrc/sliding_tile_attention  # Move into the correct folder
-          git submodule update --init --recursive tk # Ensure ThunderKittens submodule is initialized
-          python setup.py sdist --dist-dir=dist
+          cd csrc/attn  # Move into the correct folder
+          git submodule update --init --recursive # Ensure ThunderKittens submodule is initialized
+          python setup_sta.py sdist --dist-dir=dist
 
       - name: Publish release distributions to PyPI
         uses: pypa/gh-action-pypi-publish@release/v1
         with:
-          packages-dir: csrc/sliding_tile_attention/dist/
+          packages-dir: csrc/attn/dist/
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index a8b3ddf9a..9030e3f39 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -28,4 +28,4 @@ jobs:
 
       - name: Run Pytest
         run: |
-          pytest --ignore csrc/sliding_tile_attention/test
+          pytest --ignore csrc/attn/test
diff --git a/.gitignore b/.gitignore
index 240f2ae8f..0037a7803 100644
--- a/.gitignore
+++ b/.gitignore
@@ -27,7 +27,6 @@ env
 **/build/
 **.pyc
 **.txt
-csrc/attn/tk/
 
 # Distribution / packaging
 build/
diff --git a/.gitmodules b/.gitmodules
index d284208d0..e8b448235 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,3 @@
-[submodule "csrc/sliding_tile_attention/tk"]
-	path = csrc/sliding_tile_attention/tk
+[submodule "csrc/attn/tk"]
+	path = csrc/attn/tk
 	url = https://github.com/HazyResearch/ThunderKittens.git
diff --git a/csrc/attn/README.md b/csrc/attn/README.md
index 0f32d9e49..baf526c1f 100644
--- a/csrc/attn/README.md
+++ b/csrc/attn/README.md
@@ -7,26 +7,26 @@
 We test our code on Pytorch 2.5.0 and CUDA>=12.4. Currently we only have implementation on H100.
 First, install C++20 for ThunderKittens:
 
-```bash
-sudo apt update
-sudo apt install gcc-11 g++-11
-
-sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
-
-sudo apt update
-sudo apt install clang-11
-```
-Install STA:
+## Environment Setup
+First, set up your CUDA environment:
 ```bash
 export CUDA_HOME=/usr/local/cuda-12.4
 export PATH=${CUDA_HOME}/bin:${PATH} 
 export LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
 git submodule update --init --recursive
-python setup.py install
+```
+
+## Install Sliding Tile Attention (STA)
+```bash
+python setup_sta.py install
+```
+
+## Install Video Sparse Attention (VSA)
+```bash
+python setup_vsa.py install
 ```
 
 ## Usage
-
 ```python
 from st_attn import sliding_tile_attention
 # assuming video size (T, H, W) = (30, 48, 80), text tokens = 256 with padding. 
diff --git a/csrc/attn/test/test_block_sparse.py b/csrc/attn/test/test_block_sparse.py
index f8b7da8dc..42555b6fb 100644
--- a/csrc/attn/test/test_block_sparse.py
+++ b/csrc/attn/test/test_block_sparse.py
@@ -2,8 +2,8 @@ import torch
 import argparse
 from flash_attn.utils.benchmark import benchmark_forward
 from flash_attn import flash_attn_func
-from st_attn import block_sparse_attention_fwd, block_sparse_attention_backward, BlockSparseAttentionFunction
-from st_attn import BLOCK_M, BLOCK_N
+from vsa import block_sparse_attention_fwd, block_sparse_attention_backward, BlockSparseAttentionFunction
+from vsa import BLOCK_M, BLOCK_N
 
 import numpy as np
 import random
diff --git a/csrc/attn/test/test_sta.py b/csrc/attn/test/test_sta.py
index b7c3b134b..2daf99859 100644
--- a/csrc/attn/test/test_sta.py
+++ b/csrc/attn/test/test_sta.py
@@ -9,14 +9,14 @@ flex_attention = torch.compile(flex_attention, dynamic=False)
 
 
 def flex_test(Q, K, V, kernel_size):
-    mask = get_sliding_tile_attention_mask(kernel_size, (6, 8, 8), (36, 48, 48), 39, 'cuda', 0)
+    mask = get_sliding_tile_attention_mask(kernel_size, (6, 8, 8), (18, 48, 80), 0, 'cuda', 0)
     output = flex_attention(Q, K, V, block_mask=mask)
 
     return output
 
 
 def h100_fwd_kernel_test(Q, K, V, kernel_size):
-    o = sliding_tile_attention(Q, K, V, [kernel_size] * 24, 39, False)
+    o = sliding_tile_attention(Q, K, V, [kernel_size] * 24, 0, False, '18x48x80')
     return o
 
 
@@ -37,7 +37,7 @@ def check_correctness(b, h, n, d, causal, mean, std, num_iterations=50, error_mo
             'max_diff': 0
         },
     }
-    kernel_size_ls = [(6, 1, 6), (6, 6, 1)]
+    kernel_size_ls = [(3, 3, 5), (3, 1, 10)]
     from tqdm import tqdm
     for kernel_size in tqdm(kernel_size_ls):
         for _ in range(num_iterations):
@@ -74,7 +74,7 @@ def check_correctness(b, h, n, d, causal, mean, std, num_iterations=50, error_mo
 
 # Example usage
 b, h, d = 2, 24, 128
-n = 82944  # Sequence length
+n = 69120  # Sequence length
 causal = False
 mean = 1e-1
 std = 10
diff --git a/csrc/attn/tk b/csrc/attn/tk
new file mode 160000
index 000000000..1719fb726
--- /dev/null
+++ b/csrc/attn/tk
@@ -0,0 +1 @@
+Subproject commit 1719fb72641b965d26155a0515d413b007f9dc72
diff --git a/csrc/attn/vsa/__init__.py b/csrc/attn/vsa/__init__.py
index 328f7268c..0e1ccb155 100644
--- a/csrc/attn/vsa/__init__.py
+++ b/csrc/attn/vsa/__init__.py
@@ -2,7 +2,7 @@ import math
 
 import torch
 from torch.utils.checkpoint import detach_variable
-
+from typing import Tuple
 try:
     from vsa_cuda import block_sparse_fwd, block_sparse_bwd
 except ImportError:
@@ -12,33 +12,116 @@ except ImportError:
 
 BLOCK_M = 64
 BLOCK_N = 64
-def block_sparse_attention_fwd(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num):
+
+def video_sparse_attn(q, k, v, topk, block_size, compress_attn_weight=None):
     """
-    block_sparse_mask: [bs, h, num_q_blocks, num_kv_blocks]. 
-        [*, *, i, j] = 1 means the i-th q block should attend to the j-th kv block.
+    q: [batch_size, num_heads, seq_len, head_dim]
+    k: [batch_size, num_heads, seq_len, head_dim]
+    v: [batch_size, num_heads, seq_len, head_dim]
+    topk: int
+    block_size: int or tuple of 3 ints
+    video_shape: tuple of (T, H, W)
+    compress_attn_weight: [batch_size, num_heads, seq_len, head_dim]
+    select_attn_weight: [batch_size, num_heads, seq_len, head_dim]
+    
+    V1 of sparse attention. Include compress attn and sparse attn branch, use average pooling to compress. 
+    Assume q, k, v is flattened in this way: [batch_size, num_heads, T//block_size[0], H//block_size[1], W//block_size[2], block_size[0], block_size[1], block_size[2]]
     """
-    # assert all elements in q2k_block_sparse_num can be devisible by 2
-    o, lse = block_sparse_fwd(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num)
-    return o, lse
 
-def block_sparse_attention_backward(q, k, v, o, l_vec, grad_output, k2q_block_sparse_index, k2q_block_sparse_num):
-    grad_q, grad_k, grad_v = block_sparse_bwd(q, k, v, o, l_vec, grad_output, k2q_block_sparse_index, k2q_block_sparse_num)
-    return grad_q, grad_k, grad_v
+    if isinstance(block_size, int):
+        block_size = (block_size, block_size, block_size)
 
-class BlockSparseAttentionFunction(torch.autograd.Function):
-    @staticmethod
-    def forward(ctx, q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num):
-        o, lse = block_sparse_attention_fwd(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num)
-        ctx.save_for_backward(q, k, v, o, lse, k2q_block_sparse_index, k2q_block_sparse_num)
-        return o
+    block_elements = block_size[0] * block_size[1] * block_size[2]
+    assert block_elements % 64 == 0 and block_elements >= 64
+    assert q.shape[2] % block_elements == 0
+    batch_size, num_heads, seq_len, head_dim = q.shape
+    # compress attn
+    q_compress = q.view(batch_size, num_heads, seq_len // block_elements,
+                        block_elements, head_dim).mean(dim=3)
+    k_compress = k.view(batch_size, num_heads, seq_len // block_elements,
+                        block_elements, head_dim).mean(dim=3)
+    v_compress = v.view(batch_size, num_heads, seq_len // block_elements,
+                        block_elements, head_dim).mean(dim=3)
 
-    @staticmethod
-    def backward(ctx, grad_output):
-        q, k, v, o, lse, k2q_block_sparse_index, k2q_block_sparse_num = ctx.saved_tensors
-        grad_q, grad_k, grad_v = block_sparse_attention_backward(
-            q, k, v, o, lse, grad_output, k2q_block_sparse_index, k2q_block_sparse_num
-        )
-        return grad_q, grad_k, grad_v, None, None, None, None
+    output_compress, block_attn_score = torch_attention(q_compress, k_compress,
+                                                        v_compress)
+
+    output_compress = output_compress.view(batch_size, num_heads,
+                                           seq_len // block_elements, 1,
+                                           head_dim)
+    output_compress = output_compress.repeat(1, 1, 1, block_elements,
+                                             1).view(batch_size, num_heads,
+                                                     seq_len, head_dim)
+
+    q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num = generate_topk_block_sparse_pattern(
+        block_attn_score, topk)
+
+    output_select = block_sparse_attn(q, k, v, q2k_block_sparse_index,
+                                      q2k_block_sparse_num,
+                                      k2q_block_sparse_index,
+                                      k2q_block_sparse_num)
+
+    if compress_attn_weight is not None:
+        final_output = output_compress * compress_attn_weight + output_select
+    else:
+        final_output = output_compress + output_select
+    return final_output
+
+def torch_attention(q, k, v) -> Tuple[torch.Tensor, torch.Tensor]:
+    QK = torch.matmul(q, k.transpose(-2, -1))
+    QK /= (q.size(-1)**0.5)
+
+    # Causal mask removed since causal is always false
+
+    QK = torch.nn.functional.softmax(QK, dim=-1)
+    output = torch.matmul(QK, v)
+    return output, QK
+
+def generate_topk_block_sparse_pattern(block_attn_score: torch.Tensor,
+                                       topk: int):
+    """
+    Generate a block sparse pattern where each q block attends to exactly topk kv blocks,
+    based on the provided attention scores.
+    
+    Args:
+        block_attn_score: [bs, h, num_q_blocks, num_kv_blocks]
+            Attention scores between query and key blocks
+        topk: int
+            Number of kv blocks each q block attends to
+        
+    Returns:
+        q2k_block_sparse_index: [bs, h, num_q_blocks, topk]
+            Contains the indices of kv blocks that each q block attends to.
+        q2k_block_sparse_num: [bs, h, num_q_blocks]
+            Contains the number of kv blocks that each q block attends to (all equal to topk).
+        k2q_block_sparse_index: [bs, h, num_kv_blocks, max_q_per_kv]
+            Contains the indices of q blocks that attend to each kv block.
+        k2q_block_sparse_num: [bs, h, num_kv_blocks]
+            Contains the number of q blocks that attend to each kv block.
+    """
+    device = block_attn_score.device
+    # Extract dimensions from block_attn_score
+    bs, h, num_q_blocks, num_kv_blocks = block_attn_score.shape
+
+    sorted_result = torch.sort(block_attn_score, dim=-1, descending=True)
+
+    sorted_indice = sorted_result.indices
+
+    q2k_block_sparse_index, _ = torch.sort(sorted_indice[:, :, :, :topk],
+                                           dim=-1)
+    q2k_block_sparse_index = q2k_block_sparse_index.to(dtype=torch.int32)
+    q2k_block_sparse_num = torch.full((bs, h, num_q_blocks),
+                                      topk,
+                                      device=device,
+                                      dtype=torch.int32)
+
+    block_map = topk_index_to_map(q2k_block_sparse_index,
+                                  num_kv_blocks,
+                                  transpose_map=True)
+    k2q_block_sparse_index, k2q_block_sparse_num = map_to_index(
+        block_map.transpose(2, 3))
+
+    return q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num
 
 @torch._dynamo.disable
 def block_sparse_attn(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num):
@@ -61,6 +144,19 @@ def block_sparse_attn(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q
         q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num
     )
 
+def block_sparse_attention_fwd(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num):
+    """
+    block_sparse_mask: [bs, h, num_q_blocks, num_kv_blocks]. 
+        [*, *, i, j] = 1 means the i-th q block should attend to the j-th kv block.
+    """
+    # assert all elements in q2k_block_sparse_num can be devisible by 2
+    o, lse = block_sparse_fwd(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num)
+    return o, lse
+
+def block_sparse_attention_backward(q, k, v, o, l_vec, grad_output, k2q_block_sparse_index, k2q_block_sparse_num):
+    grad_q, grad_k, grad_v = block_sparse_bwd(q, k, v, o, l_vec, grad_output, k2q_block_sparse_index, k2q_block_sparse_num)
+    return grad_q, grad_k, grad_v
+
 ## pytorch sdpa version of block sparse ##
 import triton
 import triton.language as tl
@@ -128,6 +224,169 @@ def index_to_mask(q2k_block_sparse_index, q2k_block_sparse_num, BLOCK_Q, BLOCK_K
 
     return mask
 
+@triton.jit
+def topk_index_to_map_kernel(
+    map_ptr,
+    index_ptr,
+    map_bs_stride,
+    map_h_stride,
+    map_q_stride,
+    map_kv_stride,
+    index_bs_stride,
+    index_h_stride,
+    index_q_stride,
+    index_kv_stride,
+    topk: tl.constexpr,
+):
+    b, h, q = tl.program_id(0), tl.program_id(1), tl.program_id(2)
+    index_ptr_base = index_ptr + b * index_bs_stride + h * index_h_stride + q * index_q_stride
+    map_ptr_base = map_ptr + b * map_bs_stride + h * map_h_stride + q * map_q_stride
+
+    for i in tl.static_range(topk):
+        index = tl.load(index_ptr_base + i * index_kv_stride)
+        tl.store(map_ptr_base + index * map_kv_stride, 1.0)
+
+@triton.jit
+def map_to_index_kernel(
+    map_ptr,
+    index_ptr,
+    index_num_ptr,
+    map_bs_stride,
+    map_h_stride,
+    map_q_stride,
+    map_kv_stride,
+    index_bs_stride,
+    index_h_stride,
+    index_q_stride,
+    index_kv_stride,
+    index_num_bs_stride,
+    index_num_h_stride,
+    index_num_q_stride,
+    num_kv_blocks: tl.constexpr,
+):
+    b, h, q = tl.program_id(0), tl.program_id(1), tl.program_id(2)
+    index_ptr_base = index_ptr + b * index_bs_stride + h * index_h_stride + q * index_q_stride
+    map_ptr_base = map_ptr + b * map_bs_stride + h * map_h_stride + q * map_q_stride
+
+    num = 0
+    for i in tl.static_range(num_kv_blocks):
+        map_entry = tl.load(map_ptr_base + i * map_kv_stride)
+        if map_entry:
+            tl.store(index_ptr_base + num * index_kv_stride, i)
+            num += 1
+
+    tl.store(
+        index_num_ptr + b * index_num_bs_stride + h * index_num_h_stride +
+        q * index_num_q_stride, num)
+
+def topk_index_to_map(index: torch.Tensor,
+                      num_kv_blocks: int,
+                      transpose_map: bool = False):
+    """
+    Convert topk indices to a map.
+    
+    Args:
+        index: [bs, h, num_q_blocks, topk]
+            The topk indices tensor.
+        num_kv_blocks: int
+            The number of key-value blocks in the block_map returned
+        transpose_map: bool
+            If True, the block_map will be transposed on the final two dimensions.
+    
+    Returns:
+        block_map: [bs, h, num_q_blocks, num_kv_blocks]
+            A binary map where 1 indicates that the q block attends to the kv block.
+    """
+    bs, h, num_q_blocks, topk = index.shape
+
+    if transpose_map is False:
+        block_map = torch.zeros((bs, h, num_q_blocks, num_kv_blocks),
+                                dtype=torch.bool,
+                                device=index.device)
+    else:
+        block_map = torch.zeros((bs, h, num_kv_blocks, num_q_blocks),
+                                dtype=torch.bool,
+                                device=index.device)
+        block_map = block_map.transpose(2, 3)
+
+    grid = (bs, h, num_q_blocks)
+    topk_index_to_map_kernel[grid](
+        block_map,
+        index,
+        block_map.stride(0),
+        block_map.stride(1),
+        block_map.stride(2),
+        block_map.stride(3),
+        index.stride(0),
+        index.stride(1),
+        index.stride(2),
+        index.stride(3),
+        topk=topk,
+    )
+
+    return block_map
+
+def map_to_index(block_map: torch.Tensor):
+    """
+    Convert a block map to indices and counts.
+    
+    Args:
+        block_map: [bs, h, num_q_blocks, num_kv_blocks]
+            The block map tensor.
+    
+    Returns:
+        index: [bs, h, num_q_blocks, num_kv_blocks]
+            The indices of the blocks.
+        index_num: [bs, h, num_q_blocks]
+            The number of blocks for each q block.
+    """
+    bs, h, num_q_blocks, num_kv_blocks = block_map.shape
+
+    index = torch.full((block_map.shape),
+                       -1,
+                       dtype=torch.int32,
+                       device=block_map.device)
+    index_num = torch.empty((bs, h, num_q_blocks),
+                            dtype=torch.int32,
+                            device=block_map.device)
+
+    grid = (bs, h, num_q_blocks)
+    map_to_index_kernel[grid](
+        block_map,
+        index,
+        index_num,
+        block_map.stride(0),
+        block_map.stride(1),
+        block_map.stride(2),
+        block_map.stride(3),
+        index.stride(0),
+        index.stride(1),
+        index.stride(2),
+        index.stride(3),
+        index_num.stride(0),
+        index_num.stride(1),
+        index_num.stride(2),
+        num_kv_blocks=num_kv_blocks,
+    )
+
+    return index, index_num
+
+class BlockSparseAttentionFunction(torch.autograd.Function):
+    @staticmethod
+    def forward(ctx, q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num):
+        o, lse = block_sparse_attention_fwd(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num)
+        ctx.save_for_backward(q, k, v, o, lse, k2q_block_sparse_index, k2q_block_sparse_num)
+        return o
+
+    @staticmethod
+    def backward(ctx, grad_output):
+        q, k, v, o, lse, k2q_block_sparse_index, k2q_block_sparse_num = ctx.saved_tensors
+        grad_q, grad_k, grad_v = block_sparse_attention_backward(
+            q, k, v, o, lse, grad_output, k2q_block_sparse_index, k2q_block_sparse_num
+        )
+        return grad_q, grad_k, grad_v, None, None, None, None
+
+
 class DummyOperator(torch.autograd.Function):
     @staticmethod
     def forward(ctx, x):
@@ -207,4 +466,4 @@ class BlockSparseAttnTorch:
 
         o = DummyOperator.apply(output)
         o.register_hook(self.recompute)
-        return o
\ No newline at end of file
+        return o
diff --git a/fastvideo/v1/attention/backends/sliding_tile_attn.py b/fastvideo/v1/attention/backends/sliding_tile_attn.py
index c2cdac139..43ee65ca9 100644
--- a/fastvideo/v1/attention/backends/sliding_tile_attn.py
+++ b/fastvideo/v1/attention/backends/sliding_tile_attn.py
@@ -287,16 +287,10 @@ class SlidingTileAttentionImpl(AttentionImpl):
                     forward_batch.mask_search_final_result_pos[timestep].append(
                         layer_loss_save)
         else:
-            # windows = [
-            #     self.mask_strategy[timestep][layer_idx][head_idx + start_head]
-            #     for head_idx in range(head_num)
-            # ]
             windows = [
                 STA_param[head_idx + start_head] for head_idx in range(head_num)
             ]
-            # if has_text is False:
-            #     from IPython import embed
-            #     embed()
+
             hidden_states = sliding_tile_attention(
                 query, key, value, windows, text_length, has_text,
                 self.dit_seq_shape_str).transpose(1, 2)
diff --git a/fastvideo/v1/attention/backends/video_sparse_attn.py b/fastvideo/v1/attention/backends/video_sparse_attn.py
index cf9ccfd25..40000416e 100644
--- a/fastvideo/v1/attention/backends/video_sparse_attn.py
+++ b/fastvideo/v1/attention/backends/video_sparse_attn.py
@@ -1,18 +1,11 @@
 # SPDX-License-Identifier: Apache-2.0
 import math
 from dataclasses import dataclass
-from typing import Any, List, Optional, Type, cast
+from typing import List, Optional, Type
 
 import torch
-import triton
-import triton.language as tl
 from einops import rearrange
-
-try:
-    from vsa import block_sparse_attn
-except ImportError:  # noqa: E722
-    block_sparse_attn = None
-from typing import Tuple
+from vsa import video_sparse_attn
 
 from fastvideo.v1.attention.backends.abstract import (AttentionBackend,
                                                       AttentionImpl,
@@ -181,8 +174,7 @@ class VideoSparseAttentionImpl(AttentionImpl):
             (1 - attn_metadata.VSA_sparsity) *
             (self.img_seq_length / math.prod(self.VSA_base_tile_size)))
 
-        # Cast to Any to bypass type checking for untyped function
-        hidden_states = cast(Any, sparse_attn_c_s_p)(
+        hidden_states = video_sparse_attn(
             query,
             key,
             value,
@@ -191,267 +183,3 @@ class VideoSparseAttentionImpl(AttentionImpl):
             compress_attn_weight=gate_compress).transpose(1, 2)
 
         return hidden_states
-
-
-def torch_attention(q, k, v) -> Tuple[torch.Tensor, torch.Tensor]:
-    QK = torch.matmul(q, k.transpose(-2, -1))
-    QK /= (q.size(-1)**0.5)
-
-    # Causal mask removed since causal is always false
-
-    QK = torch.nn.functional.softmax(QK, dim=-1)
-    output = torch.matmul(QK, v)
-    return output, QK
-
-
-def sparse_attn_c_s_p(q, k, v, topk, block_size, compress_attn_weight=None):
-    """
-    q: [batch_size, num_heads, seq_len, head_dim]
-    k: [batch_size, num_heads, seq_len, head_dim]
-    v: [batch_size, num_heads, seq_len, head_dim]
-    topk: int
-    block_size: int or tuple of 3 ints
-    video_shape: tuple of (T, H, W)
-    compress_attn_weight: [batch_size, num_heads, seq_len, head_dim]
-    select_attn_weight: [batch_size, num_heads, seq_len, head_dim]
-    
-    V1 of sparse attention. Include compress attn and sparse attn branch, use average pooling to compress. 
-    Assume q, k, v is flattened in this way: [batch_size, num_heads, T//block_size[0], H//block_size[1], W//block_size[2], block_size[0], block_size[1], block_size[2]]
-    """
-
-    if isinstance(block_size, int):
-        block_size = (block_size, block_size, block_size)
-
-    block_elements = block_size[0] * block_size[1] * block_size[2]
-    assert block_elements % 64 == 0 and block_elements >= 64
-    assert q.shape[2] % block_elements == 0
-    batch_size, num_heads, seq_len, head_dim = q.shape
-    # compress attn
-    q_compress = q.view(batch_size, num_heads, seq_len // block_elements,
-                        block_elements, head_dim).mean(dim=3)
-    k_compress = k.view(batch_size, num_heads, seq_len // block_elements,
-                        block_elements, head_dim).mean(dim=3)
-    v_compress = v.view(batch_size, num_heads, seq_len // block_elements,
-                        block_elements, head_dim).mean(dim=3)
-
-    output_compress, block_attn_score = torch_attention(q_compress, k_compress,
-                                                        v_compress)
-
-    output_compress = output_compress.view(batch_size, num_heads,
-                                           seq_len // block_elements, 1,
-                                           head_dim)
-    output_compress = output_compress.repeat(1, 1, 1, block_elements,
-                                             1).view(batch_size, num_heads,
-                                                     seq_len, head_dim)
-
-    q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num = generate_topk_block_sparse_pattern(
-        block_attn_score, topk)
-
-    output_select = block_sparse_attn(q, k, v, q2k_block_sparse_index,
-                                      q2k_block_sparse_num,
-                                      k2q_block_sparse_index,
-                                      k2q_block_sparse_num)
-
-    if compress_attn_weight is not None:
-        final_output = output_compress * compress_attn_weight + output_select
-    else:
-        final_output = output_compress + output_select
-    return final_output
-
-
-@triton.jit
-def topk_index_to_map_kernel(
-    map_ptr,
-    index_ptr,
-    map_bs_stride,
-    map_h_stride,
-    map_q_stride,
-    map_kv_stride,
-    index_bs_stride,
-    index_h_stride,
-    index_q_stride,
-    index_kv_stride,
-    topk: tl.constexpr,
-):
-    b, h, q = tl.program_id(0), tl.program_id(1), tl.program_id(2)
-    index_ptr_base = index_ptr + b * index_bs_stride + h * index_h_stride + q * index_q_stride
-    map_ptr_base = map_ptr + b * map_bs_stride + h * map_h_stride + q * map_q_stride
-
-    for i in tl.static_range(topk):
-        index = tl.load(index_ptr_base + i * index_kv_stride)
-        tl.store(map_ptr_base + index * map_kv_stride, 1.0)
-
-
-@triton.jit
-def map_to_index_kernel(
-    map_ptr,
-    index_ptr,
-    index_num_ptr,
-    map_bs_stride,
-    map_h_stride,
-    map_q_stride,
-    map_kv_stride,
-    index_bs_stride,
-    index_h_stride,
-    index_q_stride,
-    index_kv_stride,
-    index_num_bs_stride,
-    index_num_h_stride,
-    index_num_q_stride,
-    num_kv_blocks: tl.constexpr,
-):
-    b, h, q = tl.program_id(0), tl.program_id(1), tl.program_id(2)
-    index_ptr_base = index_ptr + b * index_bs_stride + h * index_h_stride + q * index_q_stride
-    map_ptr_base = map_ptr + b * map_bs_stride + h * map_h_stride + q * map_q_stride
-
-    num = 0
-    for i in tl.static_range(num_kv_blocks):
-        map_entry = tl.load(map_ptr_base + i * map_kv_stride)
-        if map_entry:
-            tl.store(index_ptr_base + num * index_kv_stride, i)
-            num += 1
-
-    tl.store(
-        index_num_ptr + b * index_num_bs_stride + h * index_num_h_stride +
-        q * index_num_q_stride, num)
-
-
-def topk_index_to_map(index: torch.Tensor,
-                      num_kv_blocks: int,
-                      transpose_map: bool = False):
-    """
-    Convert topk indices to a map.
-    
-    Args:
-        index: [bs, h, num_q_blocks, topk]
-            The topk indices tensor.
-        num_kv_blocks: int
-            The number of key-value blocks in the block_map returned
-        transpose_map: bool
-            If True, the block_map will be transposed on the final two dimensions.
-    
-    Returns:
-        block_map: [bs, h, num_q_blocks, num_kv_blocks]
-            A binary map where 1 indicates that the q block attends to the kv block.
-    """
-    bs, h, num_q_blocks, topk = index.shape
-
-    if transpose_map is False:
-        block_map = torch.zeros((bs, h, num_q_blocks, num_kv_blocks),
-                                dtype=torch.bool,
-                                device=index.device)
-    else:
-        block_map = torch.zeros((bs, h, num_kv_blocks, num_q_blocks),
-                                dtype=torch.bool,
-                                device=index.device)
-        block_map = block_map.transpose(2, 3)
-
-    grid = (bs, h, num_q_blocks)
-    topk_index_to_map_kernel[grid](
-        block_map,
-        index,
-        block_map.stride(0),
-        block_map.stride(1),
-        block_map.stride(2),
-        block_map.stride(3),
-        index.stride(0),
-        index.stride(1),
-        index.stride(2),
-        index.stride(3),
-        topk=topk,
-    )
-
-    return block_map
-
-
-def map_to_index(block_map: torch.Tensor):
-    """
-    Convert a block map to indices and counts.
-    
-    Args:
-        block_map: [bs, h, num_q_blocks, num_kv_blocks]
-            The block map tensor.
-    
-    Returns:
-        index: [bs, h, num_q_blocks, num_kv_blocks]
-            The indices of the blocks.
-        index_num: [bs, h, num_q_blocks]
-            The number of blocks for each q block.
-    """
-    bs, h, num_q_blocks, num_kv_blocks = block_map.shape
-
-    index = torch.full((block_map.shape),
-                       -1,
-                       dtype=torch.int32,
-                       device=block_map.device)
-    index_num = torch.empty((bs, h, num_q_blocks),
-                            dtype=torch.int32,
-                            device=block_map.device)
-
-    grid = (bs, h, num_q_blocks)
-    map_to_index_kernel[grid](
-        block_map,
-        index,
-        index_num,
-        block_map.stride(0),
-        block_map.stride(1),
-        block_map.stride(2),
-        block_map.stride(3),
-        index.stride(0),
-        index.stride(1),
-        index.stride(2),
-        index.stride(3),
-        index_num.stride(0),
-        index_num.stride(1),
-        index_num.stride(2),
-        num_kv_blocks=num_kv_blocks,
-    )
-
-    return index, index_num
-
-
-def generate_topk_block_sparse_pattern(block_attn_score: torch.Tensor,
-                                       topk: int):
-    """
-    Generate a block sparse pattern where each q block attends to exactly topk kv blocks,
-    based on the provided attention scores.
-    
-    Args:
-        block_attn_score: [bs, h, num_q_blocks, num_kv_blocks]
-            Attention scores between query and key blocks
-        topk: int
-            Number of kv blocks each q block attends to
-        
-    Returns:
-        q2k_block_sparse_index: [bs, h, num_q_blocks, topk]
-            Contains the indices of kv blocks that each q block attends to.
-        q2k_block_sparse_num: [bs, h, num_q_blocks]
-            Contains the number of kv blocks that each q block attends to (all equal to topk).
-        k2q_block_sparse_index: [bs, h, num_kv_blocks, max_q_per_kv]
-            Contains the indices of q blocks that attend to each kv block.
-        k2q_block_sparse_num: [bs, h, num_kv_blocks]
-            Contains the number of q blocks that attend to each kv block.
-    """
-    device = block_attn_score.device
-    # Extract dimensions from block_attn_score
-    bs, h, num_q_blocks, num_kv_blocks = block_attn_score.shape
-
-    sorted_result = torch.sort(block_attn_score, dim=-1, descending=True)
-
-    sorted_indice = sorted_result.indices
-
-    q2k_block_sparse_index, _ = torch.sort(sorted_indice[:, :, :, :topk],
-                                           dim=-1)
-    q2k_block_sparse_index = q2k_block_sparse_index.to(dtype=torch.int32)
-    q2k_block_sparse_num = torch.full((bs, h, num_q_blocks),
-                                      topk,
-                                      device=device,
-                                      dtype=torch.int32)
-
-    block_map = topk_index_to_map(q2k_block_sparse_index,
-                                  num_kv_blocks,
-                                  transpose_map=True)
-    k2q_block_sparse_index, k2q_block_sparse_num = map_to_index(
-        block_map.transpose(2, 3))
-
-    return q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num
diff --git a/fastvideo/v1/fastvideo_args.py b/fastvideo/v1/fastvideo_args.py
index e8fef4233..d9e0f9e04 100644
--- a/fastvideo/v1/fastvideo_args.py
+++ b/fastvideo/v1/fastvideo_args.py
@@ -607,9 +607,8 @@ class TrainingArgs(FastVideoArgs):
             # Use getattr with default value from the dataclass for potentially missing attributes
             else:
                 default_value = getattr(cls, attr, None)
-                value = getattr(args, attr, default_value)
-                if value is not None:
-                    kwargs[attr] = value
+                if getattr(args, attr, default_value) is not None:
+                    kwargs[attr] = getattr(args, attr, default_value)
 
         return cls(**kwargs)