Granular Control Over Pixel Values: Mapping a Histogram
ActionScript provides elemental control over pixels, including discreet control over color Channels within Pixels (Red, Green, Blue, and Alpha/Transparency Values). A Histogram is a statistical device for visualizing the distribution of data.
In Photoshop, advanced practitioners make many of their decisions based upon an image's Histogram. An image's appearance on the monitor-which is subject to wicked variablilities such as ambient lighting and the practitioner's visual acuity- can be unreliable.
In order to determine which controls-and the manner of their application-should be employed within Flash, Photoshop, After Effects, or Premiere Pro, it is prudent to both understand and consult an image's Histogram (or RGB Parade)
Flash (ActionScript) is capable of building Histograms using the flash.display.BitmapData.histogram() Method, which returns a Vector (a type of Array with homologous elements) Object. Specifically, the product Vector of the bitmapData.histogram() Method is a multidimensional Array of Arrays of Numbers. Numbers are desirable because ActionScript 3 has a very robust Top-Level Math Class with which to investigate the statistical character of the report and to manipulate it.
Select an image and adjust its "Brightness": the Histogram will respond.
Within ActionScript we have the ability to access Pixel Channels and to map them (in this case, to a Histogram). This is by no means any sort of limit on the manipulations that can be effected on a Channel by Channel or Pixel by Pixel basis. Blending Modes (such as the Complex Mode "Hard Light") use discreet Channel values throughout Adobe's Creative Suite. ActionScript also affords various Properties and Methods in a variety of Classes with which control Pixels.
These capabilities are not simply "artistic controls" of aesthetic value only: they can be used to make photographs and various graphics more communicative-to carry a greater cognitive impact. Often, the ability to quantify and animate these manipulations makes for forensically defensible persuasive artifacts with significant communicative advantages.
The entire matter really distills that these functionalities are controllable not only via the Sliders I have provided, but as explained in previous posts (1, 2, 3):
They can be controlled by a wide variety of parameters including:
- Mouse position;
- Mouse movement direction;
- Mouse movement speed;
- Mouse button clicks;
- Keyboard input;
- Time of day;
- Touch screen input;
- Voice commands and other audio artifacts;
- Latitude and/or longitude;
- Device orientation (many have accelerometers...);
- Device movement;
- Interactive devices such as buttons or selections.
The point is that interactive visualization is engaging and makes visual artifacts more communicative: interactivity devoted to support a specific cognitive impact is engaging and persuasive. Interactivity that is rapid to produce and economical-particularly within Commercial Real Estate, Litigation Exhibits, Public Relations, Construction, Engineering, and Education industries-is highly desirable.
L
July 13th, 2011 - 16:00
Very Cool!