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Red Stripe 2 and the all new Sim Daltonism 2

Last year I released Red Stripe, a tool to help people with a red-green color blindness tell apart certain colors. It got plenty of media attention, but my impression is that it wasn’t as good as it should has been. Adding stripes everywhere the red component is higher than the green one is nice in theory, but the reality is that it can easily become misleading for intermediary colors, such as yellow.

So I took a fresh look at it in the past two months and changed the approach. There’s still stripes on red, but no longer on yellows, and there is a new kind of dashed stripes on greens. The filter has also been reworked to better handle low light situations. And it’s available today with many more improvements on iOS.

Red Stripe 2 is a free update to all users who purchased version 1.

On a Mac far away, a long 10 years ago, I made a first version of Sim Daltonism. Since then, the color blindness simulator app hasn’t changed much. I maintained it so it continued to work, making an Intel version when Macs switched to Intel processors, making it available on the Mac App Store. But if you weren’t paying attention to the version history you probably couldn’t tell what the small changes were.

That was until today. There’s an all new Sim Daltonism rebuilt on top of the Red Stripe code base. It’s unbelievably faster than the previous version and it has a new “transparent” mode where you can see through the filter window and click through it to affect windows under it. (This new mode is the default now.) In follow-the-mouse mode, the filter window will also never show up inside itself and infinitely repeat like in earlier versions, a much welcome improvement.

Moving to this new code base also brings you Sim Daltonism for iOS. Now you can look at the world through eyes having different color blindnesses. You might just find the colors a bit more boring than usual. But you could also discover things that stands out more than usual because all the other colors are fade.

Even the icon is prettier and all new.

Sim Daltonism 2 is, as always, a free app. But now with version 2 it’s even more free than that: it’s open source. Feel free to peek at the code and make some improvements of your own.

Welcome to Xcode

There’s a small unimportant thing has been nagging me since the first betas of Xcode 6 when they removed the title bar of the Welcome to Xcode window. I recognized it as nitpicky, so I didn’t complain. But it’s been long enough now that I decided I should.

Summary:
The Welcome to Xcode window can be dragged around by clicking in the
window content. But clicking on the big icon above the Welcome to
Xcode message, or anywhere inside of the icon's rectangle, will do
nothing.

Steps to Reproduce:
1. Open Xcode.
2. If the Welcome to Xcode window is not visible, choose
   Window > Welcome to Xcode.
3. Try dragging the window by clicking the icon, or in a white area
   around the icon but still inside of the icon's rect.

Expected Results:
The window should move.

Actual Results:
The window does not move; nothing happens.

Version:
Xcode 7.0 beta 5 (7A176x)
OS X 10.10.4

Notes:
Suggestion: use a subclass of NSImageView with this overridden
method:

- (BOOL)mouseDownCanMoveWindow {
    return YES;
}

That is now bug 22259311. Now I wait.

Introducing Red Stripe

As with many great ideas, this seems obvious in retrospect, but it never occurred to do it me until recently. I spent a few weeks before WWDC turning that idea into a product. And that idea got much farther than I initially expected. I’m quite pleased today to introduce you to Red Stripe for Mac and iOS.

Red Stripe is a tool to help people with a red-green color blindness distinguish colors they usually have difficulty telling apart. It works by emphasizing the red color component with a stripe pattern proportionally to its intensity relative to the blue and green component of the color. Colors such as orange, red, and purple will have a stripe overlay, while greens and blues will not.

Red Stripe for iOS is an augmented reality tool that feeds from your iPhone or iPad camera to display a world with the stripe pattern added.

It can be downloaded from the App Store for $4.99 USD.

Red Stripe for Mac displays a filtered view of the area underneath the Red Stripe window. It lets you click through the window to interact with the content underneath it.

Download it here for a free trial, and purchase it on the michelf.ca Store or the Mac App Store for $8.99 USD.

Color Blindness is a vision deficiency that affects a significant percentage of the population. It is the result of a reduced number of red, green, or blue cones on the retina, and is caused generally by defective genes on the X chromosome. You can learn more about it on Wikipedia.

For the non-color blind who want get a feel of what things look like with a color blindness, take a look at Sim Daltonism.

Gamma Control 5

Today is the release date for the fifth major version of Gamma Control. This version’s major feature is a new algorithm for tweaking the gamma curve relative to the default color profile of the screen. It’s so good that it’s now the default. More on that below.

Other added goodies include a hotkey to make the panel appear anywhere, sliders that can be manipulated by scrolling gestures, and you can now save gamma settings for multiple screens in a single file.

Gamma Control 5 will be priced at $18.99 USD, but until March 28 you can get it for $14.99. If you own an older version of Gamma Control, you’ll need to purchase a new license¹ to use version 5. Available on the michelf.ca Store or the Mac App Store.

How the Relative-to-Profile Curve Adjustment Works

Typically, gamma correction took the form of a power function where the exponent is called gamma. This created curves that looked like this:

This worked well in the days of cathode-ray tubes since the amount of light emitted by a pixel also followed a power curve depending on the input voltage applied on the electron gun. Depending on the gamma value, the curve would stretch more or less from a straight line.

But we’re all using liquid crystal displays now, and for many LCDs out there using a power function doesn’t work well. Here is how an hypothetical gamma correction curve could be like for some LCD screen:

Older versions of Gamma Control would simply wipe out this curve and replace it with a pure power-law curve as shown in the first graph. Unfortunately, there was no way to properly calibrate a screen that needs a curve like the second graph that way.

So in Gamma Control 5 there is now a “Relative to profile” mode — which is the default because it’s so nice — where instead of replacing the profile curve with one of its own, Gamma Control will calculate its curve and pass it through the profile’s curve before applying it to the screen.

The result is that if you drew the resulting curve, you’d find out that lowering the white point is equivalent to stretching the profile curve horizontally:

And if you were to make the grays darker, it’d be equivalent to compressing the curve in the higher levels and dilating it in the lower ones following a power curve:

To achieve this, Gamma Control reads the profile curve at launch, collecting samples for each level. It can then interpolate a new curve from those samples to reflect where you set your sliders. But unlike with the previous versions, if you leave all the sliders at their default position, the gamma curve will not be affected at all.