Reader: Reading Data

Reader interfaces load raw LEEM data and expose image and metadata access.

Reader defines the reader API. UViewReader parses UView .dat files. read_files() reads a list of files and returns a list of readers.

For large data stacks, it is recommended to parse the data in groups to obtain the time interval metadata (“TimeInterval” key). This is calculated based on the order of the timestamps in the metadata. Additional metadata can be added to the reader. Reader also allows quick access to the raw image data.

Example

from pyleem.reader import UViewReader, read_files

readers = read_files(
    ["data_0.dat", "data_1.dat", "data_2.dat"],
    reader_cls=UViewReader,
    metadata_list=[
        {"Voltage": (4, "V")},
        {"Voltage": (4.5, "V")},
        {"Voltage": (5, "V")},
    ],
)

# Access parsed metadata
print(readers[0].metadata["Voltage"])  # (4, 'V')
print(readers[0].metadata["TimeInterval"])  # (0.0, 's')

# Load the raw image
# ndarray, shape (height, width), uint16
image = readers[0].image

# Extract a line profile using a LineROI
from pyleem.roi import LineROI

roi = LineROI(src=(256, 0), dst=(256, 511), linewidth=10)
profile = roi.measure(image).profile

API and Reference

• Reader API: For custom reader implementations.

• reader: For full module details.