read.py

import sys
import numpy as np

def read_gvr_groundtruth(path):
    with open(path, "rb") as fid:
        version = np.fromfile(fid, count=1, dtype=np.uint8)
        assert version == 1

        is_big_endian = np.fromfile(fid, count=1, dtype=np.uint8)
        assert (is_big_endian == 1 and sys.byteorder == "big") or \
               (is_big_endian == 0 and sys.byteorder == "little")

        uint_size = np.fromfile(fid, count=1, dtype=np.uint8)
        assert uint_size == 4

        elem_size = np.fromfile(fid, count=1, dtype=np.uint32)
        if elem_size == 4:
            dtype = np.float32
        elif elem_size == 8:
            dtype = np.float64
        else:
            raise ValueError("Unsupported data type")

        num_labels = np.fromfile(fid, count=1, dtype=np.uint32)[0]
        height = np.fromfile(fid, count=1, dtype=np.uint32)[0]
        width = np.fromfile(fid, count=1, dtype=np.uint32)[0]
        depth = np.fromfile(fid, count=1, dtype=np.uint32)[0]

        num_elems = width * height * depth * num_labels
        assert num_elems > 0

        grid = np.fromfile(fid, count=num_elems, dtype=dtype)
        grid =  grid.reshape(num_labels, height, width, depth)

        grid = grid.transpose(1, 2, 3, 0)

        return grid



def read_gvr_datacost(path, num_labels):
    with open(path, "rb") as fid:
        version = np.fromfile(fid, count=1, dtype=np.uint8)
        assert version == 1

        is_big_endian = np.fromfile(fid, count=1, dtype=np.uint8)
        assert (is_big_endian == 1 and sys.byteorder == "big") or \
               (is_big_endian == 0 and sys.byteorder == "little")

        uint_size = np.fromfile(fid, count=1, dtype=np.uint8)
        assert uint_size == 4

        elem_size = np.fromfile(fid, count=1, dtype=np.uint32)
        if elem_size == 4:
            dtype = np.float32
        elif elem_size == 8:
            dtype = np.float64
        else:
            raise ValueError("Unsupported data type")

        height = np.fromfile(fid, count=1, dtype=np.uint32)[0]
        width = np.fromfile(fid, count=1, dtype=np.uint32)[0]
        depth = np.fromfile(fid, count=1, dtype=np.uint32)[0]
        assert (height % num_labels) == 0


        height //= num_labels

        num_elems = width * height * depth * num_labels
        assert num_elems > 0

        grid = np.fromfile(fid, count=num_elems, dtype=dtype)
        grid =  grid.reshape(num_labels, height, width, depth)

        grid = grid.transpose(1, 2, 3, 0)

        return grid