Truncating the last 7 bits of the weights in a saved Keras model

truncate.py

import argparse
import h5py
import numpy as np

parser = argparse.ArgumentParser()
parser.add_argument('input')
parser.add_argument('output')
args = parser.parse_args()

with h5py.File(args.output, 'w') as out:
    def visit(name, obj):
        if hasattr(obj, 'dtype'):
            assert obj.dtype == np.float32
            # round the 7 last bits
            uint32 = np.fromstring(obj.value.tostring(), dtype=np.uint32)
            uint32 += 0x00000040
            uint32 &= 0xffffff80
            truncated = np.fromstring(uint32.tostring(), dtype=np.float32).reshape(obj.value.shape)
            print('truncated', name, ', shape =', truncated.shape)
            dataset = out.create_dataset(name, data=truncated)
            for key, value in obj.attrs.items():
                print('copying attribute', key, '=>', value, 'of dataset', name)
                dataset.attrs[key] = value
        else:
            group = out.create_group(name)
            for key, value in obj.attrs.items():
                print('copying attribute', key, '=>', value, 'of group', name)
                group.attrs[key] = value

    with h5py.File(args.input) as f:
        for key, value in f.attrs.items():
            print('copying global attribute', key, '=>', value)
            out.attrs[key] = value
        f.visititems(visit)