diff options
| author | Thomas White <taw@physics.org> | 2009-11-25 18:11:33 +0100 |
|---|---|---|
| committer | Thomas White <taw@physics.org> | 2009-11-25 18:11:33 +0100 |
| commit | 0a3ed7206e2bc009ba86a8072530a3f18196cf8f (patch) | |
| tree | 6262d3e7c5ea609d9d6565638434f3e29591cc2f /src/utils.c | |
| parent | 2f3f6011e2b90a54909d5f20412c179a0cb6b37e (diff) | |
Add Poisson noise to image
Diffstat (limited to 'src/utils.c')
| -rw-r--r-- | src/utils.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/utils.c b/src/utils.c index d5e1b874..faf78502 100644 --- a/src/utils.c +++ b/src/utils.c @@ -71,3 +71,25 @@ void progress_bar(int val, int total) fflush(stdout); } + + +double poisson_noise(double expected) +{ + double L; + int k; + double p = 1.0; + + L = exp(-expected); + + do { + + double r; + + k++; + r = (double)random()/RAND_MAX; + p *= r; + + } while ( p > L ); + + return k - 1; +} |