diff --git a/reproduction_effort/functions/bandpass.py b/reproduction_effort/functions/bandpass.py
new file mode 100644
index 0000000..171baf5
--- /dev/null
+++ b/reproduction_effort/functions/bandpass.py
@@ -0,0 +1,85 @@
+import torchaudio as ta  # type: ignore
+import torch
+
+
+@torch.no_grad()
+def filtfilt(
+    input: torch.Tensor,
+    butter_a: torch.Tensor,
+    butter_b: torch.Tensor,
+) -> torch.Tensor:
+    assert butter_a.ndim == 1
+    assert butter_b.ndim == 1
+    assert butter_a.shape[0] == butter_b.shape[0]
+
+    process_data: torch.Tensor = input.detach().clone()
+
+    padding_length = 12 * int(butter_a.shape[0])
+    left_padding = 2 * process_data[..., 0].unsqueeze(-1) - process_data[
+        ..., 1 : padding_length + 1
+    ].flip(-1)
+    right_padding = 2 * process_data[..., -1].unsqueeze(-1) - process_data[
+        ..., -(padding_length + 1) : -1
+    ].flip(-1)
+    process_data_padded = torch.cat((left_padding, process_data, right_padding), dim=-1)
+
+    output = ta.functional.filtfilt(
+        process_data_padded.unsqueeze(0), butter_a, butter_b, clamp=False
+    ).squeeze(0)
+
+    output = output[..., padding_length:-padding_length]
+    return output
+
+
+@torch.no_grad()
+def butter_bandpass(
+    device: torch.device,
+    low_frequency: float = 0.1,
+    high_frequency: float = 1.0,
+    fs: float = 30.0,
+) -> tuple[torch.Tensor, torch.Tensor]:
+    import scipy  # type: ignore
+
+    butter_b_np, butter_a_np = scipy.signal.butter(
+        4, [low_frequency, high_frequency], btype="bandpass", output="ba", fs=fs
+    )
+    butter_a = torch.tensor(butter_a_np, device=device, dtype=torch.float32)
+    butter_b = torch.tensor(butter_b_np, device=device, dtype=torch.float32)
+    return butter_a, butter_b
+
+
+@torch.no_grad()
+def chunk_iterator(array: torch.Tensor, chunk_size: int):
+    for i in range(0, array.shape[0], chunk_size):
+        yield array[i : i + chunk_size]
+
+
+@torch.no_grad()
+def bandpass(
+    data: torch.Tensor,
+    device: torch.device,
+    low_frequency: float = 0.1,
+    high_frequency: float = 1.0,
+    fs=30.0,
+    filtfilt_chuck_size: int = 10,
+) -> torch.Tensor:
+    butter_a, butter_b = butter_bandpass(
+        device=device,
+        low_frequency=low_frequency,
+        high_frequency=high_frequency,
+        fs=fs,
+    )
+
+    index_full_dataset: torch.Tensor = torch.arange(
+        0, data.shape[1], device=device, dtype=torch.int64
+    )
+
+    for chunk in chunk_iterator(index_full_dataset, filtfilt_chuck_size):
+        temp_filtfilt = filtfilt(
+            data[:, chunk, :],
+            butter_a=butter_a,
+            butter_b=butter_b,
+        )
+        data[:, chunk, :] = temp_filtfilt
+
+    return data
diff --git a/reproduction_effort/functions/convert_camera_sequenc_to_list.py b/reproduction_effort/functions/convert_camera_sequenc_to_list.py
new file mode 100644
index 0000000..8aa2058
--- /dev/null
+++ b/reproduction_effort/functions/convert_camera_sequenc_to_list.py
@@ -0,0 +1,13 @@
+import torch
+
+
+@torch.no_grad()
+def convert_camera_sequenc_to_list(
+    data: torch.Tensor, required_order: list[str], cameras: list[str]
+) -> list[torch.Tensor]:
+    camera_sequence: list[torch.Tensor] = []
+
+    for cam in required_order:
+        camera_sequence.append(data[:, :, :, cameras.index(cam)].clone())
+
+    return camera_sequence
diff --git a/reproduction_effort/functions/gauss_smear.py b/reproduction_effort/functions/gauss_smear.py
new file mode 100644
index 0000000..15abfed
--- /dev/null
+++ b/reproduction_effort/functions/gauss_smear.py
@@ -0,0 +1,41 @@
+import torch
+from functions.gauss_smear_individual import gauss_smear_individual
+
+
+@torch.no_grad()
+def gauss_smear(
+    input_cameras: list[torch.Tensor],
+    input_mask: torch.Tensor,
+    spatial_width: float,
+    temporal_width: float,
+    use_matlab_mask: bool = True,
+    epsilon: float = float(torch.finfo(torch.float64).eps),
+) -> list[torch.Tensor]:
+    assert len(input_cameras) == 4
+
+    filtered_mask: torch.Tensor
+    filtered_mask, _ = gauss_smear_individual(
+        input=input_mask,
+        spatial_width=spatial_width,
+        temporal_width=temporal_width,
+        use_matlab_mask=use_matlab_mask,
+        epsilon=epsilon,
+    )
+
+    overwrite_fft_gauss: None | torch.Tensor = None
+    for id in range(0, len(input_cameras)):
+
+        input_cameras[id] *= input_mask.unsqueeze(-1)
+        input_cameras[id], overwrite_fft_gauss = gauss_smear_individual(
+            input=input_cameras[id],
+            spatial_width=spatial_width,
+            temporal_width=temporal_width,
+            overwrite_fft_gauss=overwrite_fft_gauss,
+            use_matlab_mask=use_matlab_mask,
+            epsilon=epsilon,
+        )
+
+        input_cameras[id] /= filtered_mask + 1e-20
+        input_cameras[id] += 1.0 - input_mask.unsqueeze(-1)
+
+    return input_cameras
diff --git a/reproduction_effort/functions/gauss_smear_individual.py b/reproduction_effort/functions/gauss_smear_individual.py
new file mode 100644
index 0000000..36700e7
--- /dev/null
+++ b/reproduction_effort/functions/gauss_smear_individual.py
@@ -0,0 +1,127 @@
+import torch
+import math
+
+
+@torch.no_grad()
+def gauss_smear_individual(
+    input: torch.Tensor,
+    spatial_width: float,
+    temporal_width: float,
+    overwrite_fft_gauss: None | torch.Tensor = None,
+    use_matlab_mask: bool = True,
+    epsilon: float = float(torch.finfo(torch.float64).eps),
+) -> tuple[torch.Tensor, torch.Tensor]:
+
+    dim_x: int = int(2 * math.ceil(2 * spatial_width) + 1)
+    dim_y: int = int(2 * math.ceil(2 * spatial_width) + 1)
+    dim_t: int = int(2 * math.ceil(2 * temporal_width) + 1)
+    dims_xyt: torch.Tensor = torch.tensor(
+        [dim_x, dim_y, dim_t], dtype=torch.int64, device=input.device
+    )
+
+    if input.ndim == 2:
+        input = input.unsqueeze(-1)
+
+    input_padded = torch.nn.functional.pad(
+        input.unsqueeze(0),
+        pad=(
+            dim_t,
+            dim_t,
+            dim_y,
+            dim_y,
+            dim_x,
+            dim_x,
+        ),
+        mode="replicate",
+    ).squeeze(0)
+
+    if overwrite_fft_gauss is None:
+        center_x: int = int(math.ceil(input_padded.shape[0] / 2))
+        center_y: int = int(math.ceil(input_padded.shape[1] / 2))
+        center_z: int = int(math.ceil(input_padded.shape[2] / 2))
+        grid_x: torch.Tensor = (
+            torch.arange(0, input_padded.shape[0], device=input.device) - center_x + 1
+        )
+        grid_y: torch.Tensor = (
+            torch.arange(0, input_padded.shape[1], device=input.device) - center_y + 1
+        )
+        grid_z: torch.Tensor = (
+            torch.arange(0, input_padded.shape[2], device=input.device) - center_z + 1
+        )
+
+        grid_x = grid_x.unsqueeze(-1).unsqueeze(-1) ** 2
+        grid_y = grid_y.unsqueeze(0).unsqueeze(-1) ** 2
+        grid_z = grid_z.unsqueeze(0).unsqueeze(0) ** 2
+
+        gauss_kernel: torch.Tensor = (
+            (grid_x / (spatial_width**2))
+            + (grid_y / (spatial_width**2))
+            + (grid_z / (temporal_width**2))
+        )
+
+        if use_matlab_mask:
+            filter_radius: torch.Tensor = (dims_xyt - 1) // 2
+
+            border_lower: list[int] = [
+                center_x - int(filter_radius[0]) - 1,
+                center_y - int(filter_radius[1]) - 1,
+                center_z - int(filter_radius[2]) - 1,
+            ]
+
+            border_upper: list[int] = [
+                center_x + int(filter_radius[0]),
+                center_y + int(filter_radius[1]),
+                center_z + int(filter_radius[2]),
+            ]
+
+            matlab_mask: torch.Tensor = torch.zeros_like(gauss_kernel)
+            matlab_mask[
+                border_lower[0] : border_upper[0],
+                border_lower[1] : border_upper[1],
+                border_lower[2] : border_upper[2],
+            ] = 1.0
+
+        gauss_kernel = torch.exp(-gauss_kernel / 2.0)
+        if use_matlab_mask:
+            gauss_kernel = gauss_kernel * matlab_mask
+
+        gauss_kernel[gauss_kernel < (epsilon * gauss_kernel.max())] = 0
+
+        sum_gauss_kernel: float = float(gauss_kernel.sum())
+
+        if sum_gauss_kernel != 0.0:
+            gauss_kernel = gauss_kernel / sum_gauss_kernel
+
+        # FFT Shift
+        gauss_kernel = torch.cat(
+            (gauss_kernel[center_x - 1 :, :, :], gauss_kernel[: center_x - 1, :, :]),
+            dim=0,
+        )
+        gauss_kernel = torch.cat(
+            (gauss_kernel[:, center_y - 1 :, :], gauss_kernel[:, : center_y - 1, :]),
+            dim=1,
+        )
+        gauss_kernel = torch.cat(
+            (gauss_kernel[:, :, center_z - 1 :], gauss_kernel[:, :, : center_z - 1]),
+            dim=2,
+        )
+        overwrite_fft_gauss = torch.fft.fftn(gauss_kernel)
+        input_padded_gauss_filtered: torch.Tensor = torch.real(
+            torch.fft.ifftn(torch.fft.fftn(input_padded) * overwrite_fft_gauss)
+        )
+    else:
+        input_padded_gauss_filtered = torch.real(
+            torch.fft.ifftn(torch.fft.fftn(input_padded) * overwrite_fft_gauss)
+        )
+
+    start = dims_xyt
+    stop = (
+        torch.tensor(input_padded.shape, device=dims_xyt.device, dtype=dims_xyt.dtype)
+        - dims_xyt
+    )
+
+    output = input_padded_gauss_filtered[
+        start[0] : stop[0], start[1] : stop[1], start[2] : stop[2]
+    ]
+
+    return (output, overwrite_fft_gauss)
diff --git a/reproduction_effort/functions/interpolate_along_time.py b/reproduction_effort/functions/interpolate_along_time.py
new file mode 100644
index 0000000..d747cb9
--- /dev/null
+++ b/reproduction_effort/functions/interpolate_along_time.py
@@ -0,0 +1,11 @@
+import torch
+
+
+def interpolate_along_time(camera_sequence: list[torch.Tensor]) -> None:
+    camera_sequence[2][:, :, 1:] = (
+        camera_sequence[2][:, :, 1:] + camera_sequence[2][:, :, :-1]
+    ) / 2.0
+
+    camera_sequence[3][:, :, 1:] = (
+        camera_sequence[3][:, :, 1:] + camera_sequence[3][:, :, :-1]
+    ) / 2.0
diff --git a/reproduction_effort/functions/make_mask.py b/reproduction_effort/functions/make_mask.py
new file mode 100644
index 0000000..0e6bdf4
--- /dev/null
+++ b/reproduction_effort/functions/make_mask.py
@@ -0,0 +1,26 @@
+import scipy.io as sio  # type: ignore
+
+import torch
+
+
+@torch.no_grad()
+def make_mask(
+    filename_mask: str, data: torch.Tensor, device: torch.device, dtype: torch.dtype
+) -> torch.Tensor:
+    mask: torch.Tensor = torch.tensor(
+        sio.loadmat(filename_mask)["maskInfo"]["maskIdx2D"][0][0],
+        device=device,
+        dtype=torch.bool,
+    )
+    mask = mask > 0.5
+
+    limit: torch.Tensor = torch.tensor(
+        2**16 - 1,
+        device=device,
+        dtype=dtype,
+    )
+
+    if torch.any(data.flatten() >= limit):
+        mask = mask & ~(torch.any(torch.any(data >= limit, dim=-1), dim=-1))
+
+    return mask
diff --git a/reproduction_effort/functions/preprocess_camera_sequence.py b/reproduction_effort/functions/preprocess_camera_sequence.py
new file mode 100644
index 0000000..d6d2555
--- /dev/null
+++ b/reproduction_effort/functions/preprocess_camera_sequence.py
@@ -0,0 +1,36 @@
+import torch
+
+
+@torch.no_grad()
+def preprocess_camera_sequence(
+    camera_sequence: torch.Tensor,
+    mask: torch.Tensor,
+    first_none_ramp_frame: int,
+    device: torch.device,
+    dtype: torch.dtype,
+) -> tuple[torch.Tensor, torch.Tensor]:
+
+    limit: torch.Tensor = torch.tensor(
+        2**16 - 1,
+        device=device,
+        dtype=dtype,
+    )
+
+    camera_sequence = camera_sequence / camera_sequence[
+        :, :, first_none_ramp_frame:
+    ].mean(
+        dim=2,
+        keepdim=True,
+    )
+
+    camera_sequence = camera_sequence.nan_to_num(nan=0.0)
+
+    camera_sequence_zero_idx = torch.any(camera_sequence == 0, dim=-1, keepdim=True)
+    mask &= (~camera_sequence_zero_idx.squeeze(-1)).type(dtype=torch.bool)
+    camera_sequence_zero_idx = torch.tile(
+        camera_sequence_zero_idx, (1, 1, camera_sequence.shape[-1])
+    )
+    camera_sequence_zero_idx[:, :, :first_none_ramp_frame] = False
+    camera_sequence[camera_sequence_zero_idx] = limit
+
+    return camera_sequence, mask
diff --git a/reproduction_effort/functions/preprocessing.py b/reproduction_effort/functions/preprocessing.py
new file mode 100644
index 0000000..2fd12b4
--- /dev/null
+++ b/reproduction_effort/functions/preprocessing.py
@@ -0,0 +1,93 @@
+import scipy.io as sio  # type: ignore
+import torch
+import numpy as np
+import json
+
+from functions.make_mask import make_mask
+from functions.convert_camera_sequenc_to_list import convert_camera_sequenc_to_list
+from functions.preprocess_camera_sequence import preprocess_camera_sequence
+from functions.interpolate_along_time import interpolate_along_time
+from functions.gauss_smear import gauss_smear
+from functions.regression import regression
+
+
+@torch.no_grad()
+def preprocessing(
+    filename_metadata: str,
+    filename_data: str,
+    filename_mask: str,
+    device: torch.device,
+    first_none_ramp_frame: int,
+    spatial_width: float,
+    temporal_width: float,
+    target_camera: list[str],
+    regressor_cameras: list[str],
+    dtype: torch.dtype = torch.float32,
+) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
+
+    data: torch.Tensor = torch.tensor(
+        sio.loadmat(filename_data)["data"].astype(np.float32),
+        device=device,
+        dtype=dtype,
+    )
+
+    with open(filename_metadata, "r") as file_handle:
+        metadata: dict = json.load(file_handle)
+    cameras: list[str] = metadata["channelKey"]
+
+    required_order: list[str] = ["acceptor", "donor", "oxygenation", "volume"]
+
+    mask: torch.Tensor = make_mask(
+        filename_mask=filename_mask, data=data, device=device, dtype=dtype
+    )
+
+    camera_sequence: list[torch.Tensor] = convert_camera_sequenc_to_list(
+        data=data, required_order=required_order, cameras=cameras
+    )
+
+    for num_cams in range(len(camera_sequence)):
+        camera_sequence[num_cams], mask = preprocess_camera_sequence(
+            camera_sequence=camera_sequence[num_cams],
+            mask=mask,
+            first_none_ramp_frame=first_none_ramp_frame,
+            device=device,
+            dtype=dtype,
+        )
+
+    # Interpolate in-between images
+    interpolate_along_time(camera_sequence)
+
+    camera_sequence_filtered: list[torch.Tensor] = []
+    for id in range(0, len(camera_sequence)):
+        camera_sequence_filtered.append(camera_sequence[id].clone())
+
+    camera_sequence_filtered = gauss_smear(
+        camera_sequence_filtered,
+        mask.type(dtype=dtype),
+        spatial_width=spatial_width,
+        temporal_width=temporal_width,
+    )
+
+    regressor_camera_ids: list[int] = []
+
+    for cam in regressor_cameras:
+        regressor_camera_ids.append(cameras.index(cam))
+
+    results: list[torch.Tensor] = []
+
+    for channel_position in range(0, len(target_camera)):
+        print(f"channel position: {channel_position}")
+        target_camera_selected = target_camera[channel_position]
+        target_camera_id: int = cameras.index(target_camera_selected)
+
+        output = regression(
+            target_camera_id=target_camera_id,
+            regressor_camera_ids=regressor_camera_ids,
+            mask=mask,
+            camera_sequence=camera_sequence,
+            camera_sequence_filtered=camera_sequence_filtered,
+            first_none_ramp_frame=first_none_ramp_frame,
+        )
+        results.append(output)
+
+    return results[0], results[1], mask
diff --git a/reproduction_effort/functions/regression.py b/reproduction_effort/functions/regression.py
new file mode 100644
index 0000000..c273d0a
--- /dev/null
+++ b/reproduction_effort/functions/regression.py
@@ -0,0 +1,118 @@
+import torch
+from functions.regression_internal import regression_internal
+
+
+@torch.no_grad()
+def regression(
+    target_camera_id: int,
+    regressor_camera_ids: list[int],
+    mask: torch.Tensor,
+    camera_sequence: list[torch.Tensor],
+    camera_sequence_filtered: list[torch.Tensor],
+    first_none_ramp_frame: int,
+) -> torch.Tensor:
+
+    assert len(regressor_camera_ids) > 0
+
+    # ------- Prepare the target signals ----------
+    target_signals_train: torch.Tensor = (
+        camera_sequence_filtered[target_camera_id][..., first_none_ramp_frame:].clone()
+        - 1.0
+    )
+    target_signals_train[target_signals_train < -1] = 0.0
+
+    target_signals_perform: torch.Tensor = (
+        camera_sequence[target_camera_id].clone() - 1.0
+    )
+
+    # Check if everything is happy
+    assert target_signals_train.ndim == 3
+    assert target_signals_train.ndim == target_signals_perform.ndim
+    assert target_signals_train.shape[0] == target_signals_perform.shape[0]
+    assert target_signals_train.shape[1] == target_signals_perform.shape[1]
+    assert (
+        target_signals_train.shape[2] + first_none_ramp_frame
+    ) == target_signals_perform.shape[2]
+    # --==DONE==-
+
+    # ------- Prepare the regressor signals ----------
+
+    # --- Train ---
+
+    regressor_signals_train: torch.Tensor = torch.zeros(
+        (
+            camera_sequence_filtered[0].shape[0],
+            camera_sequence_filtered[0].shape[1],
+            camera_sequence_filtered[0].shape[2],
+            len(regressor_camera_ids) + 1,
+        ),
+        device=camera_sequence_filtered[0].device,
+        dtype=camera_sequence_filtered[0].dtype,
+    )
+
+    # Copy the regressor signals -1
+    for matrix_id, id in enumerate(regressor_camera_ids):
+        regressor_signals_train[..., matrix_id] = camera_sequence_filtered[id] - 1.0
+
+    regressor_signals_train[regressor_signals_train < -1] = 0.0
+
+    # Linear regressor
+    trend = torch.arange(
+        0, regressor_signals_train.shape[-2], device=camera_sequence_filtered[0].device
+    ) / float(regressor_signals_train.shape[-2] - 1)
+    trend -= trend.mean()
+    trend = trend.unsqueeze(0).unsqueeze(0)
+    trend = trend.tile(
+        (regressor_signals_train.shape[0], regressor_signals_train.shape[1], 1)
+    )
+    regressor_signals_train[..., -1] = trend
+
+    regressor_signals_train = regressor_signals_train[:, :, first_none_ramp_frame:, :]
+
+    # --- Perform ---
+
+    regressor_signals_perform: torch.Tensor = torch.zeros(
+        (
+            camera_sequence[0].shape[0],
+            camera_sequence[0].shape[1],
+            camera_sequence[0].shape[2],
+            len(regressor_camera_ids) + 1,
+        ),
+        device=camera_sequence[0].device,
+        dtype=camera_sequence[0].dtype,
+    )
+
+    # Copy the regressor signals -1
+    for matrix_id, id in enumerate(regressor_camera_ids):
+        regressor_signals_perform[..., matrix_id] = camera_sequence[id] - 1.0
+
+    # Linear regressor
+    trend = torch.arange(
+        0, regressor_signals_perform.shape[-2], device=camera_sequence[0].device
+    ) / float(regressor_signals_perform.shape[-2] - 1)
+    trend -= trend.mean()
+    trend = trend.unsqueeze(0).unsqueeze(0)
+    trend = trend.tile(
+        (regressor_signals_perform.shape[0], regressor_signals_perform.shape[1], 1)
+    )
+    regressor_signals_perform[..., -1] = trend
+
+    # --==DONE==-
+
+    coefficients, intercept = regression_internal(
+        input_regressor=regressor_signals_train, input_target=target_signals_train
+    )
+
+    target_signals_perform -= (
+        regressor_signals_perform * coefficients.unsqueeze(-2)
+    ).sum(dim=-1)
+
+    target_signals_perform -= intercept.unsqueeze(-1)
+
+    target_signals_perform[
+        ~mask.unsqueeze(-1).tile((1, 1, target_signals_perform.shape[-1]))
+    ] = 0.0
+
+    target_signals_perform += 1.0
+
+    return target_signals_perform
diff --git a/reproduction_effort/functions/regression_internal.py b/reproduction_effort/functions/regression_internal.py
new file mode 100644
index 0000000..352d7ba
--- /dev/null
+++ b/reproduction_effort/functions/regression_internal.py
@@ -0,0 +1,20 @@
+import torch
+
+
+def regression_internal(
+    input_regressor: torch.Tensor, input_target: torch.Tensor
+) -> tuple[torch.Tensor, torch.Tensor]:
+
+    regressor_offset = input_regressor.mean(keepdim=True, dim=-2)
+    target_offset = input_target.mean(keepdim=True, dim=-1)
+
+    regressor = input_regressor - regressor_offset
+    target = input_target - target_offset
+
+    coefficients, _, _, _ = torch.linalg.lstsq(regressor, target, rcond=None)  # None ?
+
+    intercept = target_offset.squeeze(-1) - (
+        coefficients * regressor_offset.squeeze(-2)
+    ).sum(dim=-1)
+
+    return coefficients, intercept
diff --git a/reproduction_effort/heartbeatanalyse.py b/reproduction_effort/heartbeatanalyse.py
new file mode 100644
index 0000000..8a26474
--- /dev/null
+++ b/reproduction_effort/heartbeatanalyse.py
@@ -0,0 +1,122 @@
+import torch
+import matplotlib.pyplot as plt
+
+
+from functions.preprocessing import preprocessing
+from functions.bandpass import bandpass
+
+
+if __name__ == "__main__":
+
+    if torch.cuda.is_available():
+        device_name: str = "cuda:0"
+    else:
+        device_name = "cpu"
+    print(f"Using device: {device_name}")
+    device: torch.device = torch.device(device_name)
+
+    filename_metadata: str = "raw/Exp001_Trial001_Part001_meta.txt"
+    filename_data: str = "Exp001_Trial001_Part001.mat"
+    filename_mask: str = "2020-12-08maskPixelraw2.mat"
+
+    first_none_ramp_frame: int = 100
+    spatial_width: float = 2
+    temporal_width: float = 0.1
+
+    lower_freqency_bandpass: float = 5.0
+    upper_freqency_bandpass: float = 14.0
+
+    target_camera: list[str] = ["acceptor", "donor"]
+    regressor_cameras: list[str] = ["oxygenation", "volume"]
+
+    ratio_sequence_a, ratio_sequence_b, mask = preprocessing(
+        filename_metadata=filename_metadata,
+        filename_data=filename_data,
+        filename_mask=filename_mask,
+        device=device,
+        first_none_ramp_frame=first_none_ramp_frame,
+        spatial_width=spatial_width,
+        temporal_width=temporal_width,
+        target_camera=target_camera,
+        regressor_cameras=regressor_cameras,
+    )
+
+    ratio_sequence_a = bandpass(
+        data=ratio_sequence_a,
+        device=ratio_sequence_a.device,
+        low_frequency=lower_freqency_bandpass,
+        high_frequency=upper_freqency_bandpass,
+        fs=100.0,
+        filtfilt_chuck_size=10,
+    )
+
+    ratio_sequence_b = bandpass(
+        data=ratio_sequence_b,
+        device=ratio_sequence_b.device,
+        low_frequency=lower_freqency_bandpass,
+        high_frequency=upper_freqency_bandpass,
+        fs=100.0,
+        filtfilt_chuck_size=10,
+    )
+
+    original_shape = ratio_sequence_a.shape
+
+    ratio_sequence_a = ratio_sequence_a.flatten(start_dim=0, end_dim=-2)
+    ratio_sequence_b = ratio_sequence_b.flatten(start_dim=0, end_dim=-2)
+
+    mask = mask.flatten(start_dim=0, end_dim=-1)
+    ratio_sequence_a = ratio_sequence_a[mask, :]
+    ratio_sequence_b = ratio_sequence_b[mask, :]
+
+    ratio_sequence_a = ratio_sequence_a.movedim(0, -1)
+    ratio_sequence_b = ratio_sequence_b.movedim(0, -1)
+
+    ratio_sequence_a -= ratio_sequence_a.mean(dim=0, keepdim=True)
+    ratio_sequence_b -= ratio_sequence_b.mean(dim=0, keepdim=True)
+
+    u_a, s_a, Vh_a = torch.linalg.svd(ratio_sequence_a, full_matrices=False)
+    u_a = u_a[:, 0]
+    s_a = s_a[0]
+    Vh_a = Vh_a[0, :]
+
+    heartbeatactivitmap_a = torch.zeros(
+        (original_shape[0], original_shape[1]), device=Vh_a.device, dtype=Vh_a.dtype
+    ).flatten(start_dim=0, end_dim=-1)
+
+    heartbeatactivitmap_a *= torch.nan
+    heartbeatactivitmap_a[mask] = s_a * Vh_a
+    heartbeatactivitmap_a = heartbeatactivitmap_a.reshape(
+        (original_shape[0], original_shape[1])
+    )
+
+    u_b, s_b, Vh_b = torch.linalg.svd(ratio_sequence_b, full_matrices=False)
+    u_b = u_b[:, 0]
+    s_b = s_b[0]
+    Vh_b = Vh_b[0, :]
+
+    heartbeatactivitmap_b = torch.zeros(
+        (original_shape[0], original_shape[1]), device=Vh_b.device, dtype=Vh_b.dtype
+    ).flatten(start_dim=0, end_dim=-1)
+
+    heartbeatactivitmap_b *= torch.nan
+    heartbeatactivitmap_b[mask] = s_b * Vh_b
+    heartbeatactivitmap_b = heartbeatactivitmap_b.reshape(
+        (original_shape[0], original_shape[1])
+    )
+
+    plt.subplot(2, 1, 1)
+    plt.plot(u_a.cpu(), label="aceptor")
+    plt.plot(u_b.cpu(), label="donor")
+    plt.legend()
+    plt.subplot(2, 1, 2)
+    plt.imshow(
+        torch.cat(
+            (
+                heartbeatactivitmap_a,
+                heartbeatactivitmap_b,
+            ),
+            dim=1,
+        ).cpu()
+    )
+    plt.colorbar()
+    plt.show()
diff --git a/reproduction_effort/preprocessing.py b/reproduction_effort/preprocessing.py
new file mode 100644
index 0000000..483a81e
--- /dev/null
+++ b/reproduction_effort/preprocessing.py
@@ -0,0 +1,68 @@
+import torch
+import numpy as np
+import matplotlib.pyplot as plt
+import h5py  # type: ignore
+
+from functions.preprocessing import preprocessing
+
+
+if __name__ == "__main__":
+
+    if torch.cuda.is_available():
+        device_name: str = "cuda:0"
+    else:
+        device_name = "cpu"
+    print(f"Using device: {device_name}")
+    device: torch.device = torch.device(device_name)
+
+    filename_metadata: str = "raw/Exp001_Trial001_Part001_meta.txt"
+    filename_data: str = "Exp001_Trial001_Part001.mat"
+    filename_mask: str = "2020-12-08maskPixelraw2.mat"
+
+    first_none_ramp_frame: int = 100
+    spatial_width: float = 2
+    temporal_width: float = 0.1
+
+    target_camera: list[str] = ["acceptor", "donor"]
+    regressor_cameras: list[str] = ["oxygenation", "volume"]
+
+    data_acceptor, data_donor, mask = preprocessing(
+        filename_metadata=filename_metadata,
+        filename_data=filename_data,
+        filename_mask=filename_mask,
+        device=device,
+        first_none_ramp_frame=first_none_ramp_frame,
+        spatial_width=spatial_width,
+        temporal_width=temporal_width,
+        target_camera=target_camera,
+        regressor_cameras=regressor_cameras,
+    )
+
+    ratio_sequence: torch.Tensor = data_acceptor / data_donor
+
+    new: np.ndarray = ratio_sequence.cpu().numpy()
+
+    file_handle = h5py.File("old.mat", "r")
+    old: np.ndarray = np.array(file_handle["ratioSequence"])
+    # HDF5 loads everything backwards...
+    old = np.moveaxis(old, 0, -1)
+    old = np.moveaxis(old, 0, -2)
+
+    pos_x = 25
+    pos_y = 75
+
+    plt.subplot(2, 1, 1)
+    new_select = new[pos_x, pos_y, :]
+    old_select = old[pos_x, pos_y, :]
+    plt.plot(new_select, label="New")
+    plt.plot(old_select, "--", label="Old")
+    plt.plot(old_select - new_select + 1.0, label="Old - New + 1")
+    plt.title(f"Position: {pos_x}, {pos_y}")
+    plt.legend()
+
+    plt.subplot(2, 1, 2)
+    differences = (np.abs(new - old)).max(axis=-1)
+    plt.imshow(differences)
+    plt.title("Max of abs(new-old) along time")
+    plt.colorbar()
+    plt.show()