Hello,

Introduction:
I'm currently working on retrieving altitude values from a a
file(srtm). This file contains a array of byte values and depending of
the position i want to know, i have to read to byte's to know what the
altitude is.
This works fine, till i want to convert the bytes to a integer value,
representing the height on that specific place on theworld.
I've asked this question before on this list, but i got a pointer to a
library but this doesnt solve the problem i have.

The problem:
I have 2 bytes, which represents a signed integer (this means thevalue
can also be negative), so i want a function with the following
definition.

public static int getSignedIntegerFromBigEndian2Bytes(byte[] word) {
    ...
    ...
    ...
}
I looked at the BitConverter.GetInt16(), but this does not work for
the bytes i want to convert. In an earlier post Jon Skeet suggested to
use his MiscUtil project (which can be found on http://pobox.com/~skeet/csharp/miscutil),
especially the class MiscUtil.Conversion.BigEndianBitConverter and i
expect the function FromBytes only this doesnt return bytes or an
signed value.

I really expect that this problem could be solved within like 4 lines,
but i dont know where to start, so this is the reason why i turned to
this list. I am in the impression that the information i give is clear
enough, and otherwise feel free to ask for more information

Sample data:
byte[0] byte[1] 0-in bits       1-in bits       word in
bits            expected value
255     236     11111111        11101100
1111111111101100        -20
255     246     11111111        11110110
1111111111110110        -10
255     255     11111111        11111111
1111111111111111        -1
0       0       00000000        00000000
0000000000000000        0
0       1       00000000        00000001
0000000000000001        1
0       10      00000000        00001010
0000000000001010        10
0       20      00000000        00010100
0000000000010100        20

Eduard Witteveen