如果以字符形式读取文件，则可以使用strtoi

hex_to_int = function(x) {
  i = 256^(0:(length(x)-1)) * strtoi(x, base = 16L)
  sum(i)
}

x  = c("92", "02", "00", "00")
hex_to_int(x)
# [1] 658

如果你有一个原始向量，你可以使用readBin转换成整数。

x <- as.raw(c(146, 2, 0, 0))
x
# [1] 92 02 00 00
readBin(x, integer(), n=1, size=4, endian = "little")
# [1] 658

其中一种方法是手动操作：

get_32bit_unsigned <- function(raw_32bit) {
  if(!( inherits(raw_32bit, 'raw') & length(raw_32bit) == 4)) {
    rlang::abort('raw_32bit must be a 32-bit raw vector')
  }
  width_in_bits = rawToBits(raw_32bit)
  v = 0
  for(i in 1:length(width_in_bits)) {
    v = v + 2^(i-1)*as.integer(width_in_bits[i])
  }
  return(v)
}

get_32bit_unsigned(readBin(img_path, "raw", 20)[17:20])
> 658