----------------------------------------------------------------------------- name: hamming() desc: make window -----------------------------------------------------------------------------
| 41 | // desc: make window |
| 42 | //----------------------------------------------------------------------------- |
| 43 | void hamming(float * window, unsigned long length) |
| 44 | { |
| 45 | unsigned long i; |
| 46 | double pi, phase = 0, delta; |
| 47 | |
| 48 | pi = 4.*atan(1.0); |
| 49 | delta = 2 * pi / (double)length; |
| 50 | |
| 51 | for (i = 0; i < length; i++) |
| 52 | { |
| 53 | window[i] = (float)(0.54 - .46*cos(phase)); |
| 54 | phase += delta; |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | |
| 59 |