Hi there, Does anyone have Steve Harris' new email address? st...@plugin.org.uk fails with "550 5.1.2 Bad destination system address".
Anyway, some of you who package or copied code from meterbridge may be
interested in this as well.
-=-=-=-=-
Hi Steve,
Haven't seen you around much on LAD. I hope this email finds you well.
Are you still maintaining meterbridge? I've stumbled over a bug in 0.9.2
The IEC scale is not continuous. Attached patch resolves the issue.
I don't have access to the IEC-268-18 specs, so I can't tell if the
patch is correct, but it does fix the discontinuity between -60db and
-50db. To make it obvious, here's the annotated iec_scale(float db):
if (db < -70.0f) {
def = 0.0f;
} else if (db < -60.0f) {
def = (db + 70.0f) * 0.25f; // 0.0 .. 2.5
} else if (db < -50.0f) {
// def = (db + 60.0f) * 0.5f + 5.0f; // 5.0 .. 10.0 // bug? v0.9.2
def = (db + 60.0f) * 0.5f + 2.5f; // 2.5 .. 7.5 // fix!
} else if (db < -40.0f) {
def = (db + 50.0f) * 0.75f + 7.5; // 7.5 .. 15.0
} else if (db < -30.0f) {
def = (db + 40.0f) * 1.5f + 15.0f; // 15.0 .. 30.0
} else if (db < -20.0f) {
def = (db + 30.0f) * 2.0f + 30.0f; // 30.0 .. 50.0
} else if (db < 0.0f) {
def = (db + 20.0f) * 2.5f + 50.0f; // 50.0 .. 100.0
} else {
def = 100.0f;
}
Furthermore, the DPM image has a couple of problems:
The markers at -10, -19, -20, -25, -30, -35, -55 are off by one pixel
(they need to be moved 1px down), the -45db marker is correct.
The marks for -40, and -50 are missing and it's easy to mistake the
-45db and -55db marks to correspond to the -40db, -50db annotations.
Last but not least, the minus-signs of all annotation does not align
with the marks and the font used for the annotation text is somewhat
blurry..
All fixed in attached image.
Cheers!
robin
diff --git a/src/dpm_meters.c b/src/dpm_meters.c
index 34738c2..b1ea69c 100644
--- a/src/dpm_meters.c
+++ b/src/dpm_meters.c
@@ -33,7 +33,7 @@ int iec_scale(float db) {
} else if (db < -60.0f) {
def = (db + 70.0f) * 0.25f;
} else if (db < -50.0f) {
- def = (db + 60.0f) * 0.5f + 5.0f;
+ def = (db + 60.0f) * 0.5f + 2.5f;
} else if (db < -40.0f) {
def = (db + 50.0f) * 0.75f + 7.5;
} else if (db < -30.0f) {
<<attachment: iec268-scale.png>>
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