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This page provides a more detailed discussion of the components and function of MEAPsoft. For a quick illustration of how to get going, see the MEAPsoft Quick Start Walkthrough.
The segmenter analyzes the input sound file and outputs a list of segments representing events or beats present in the sound.
Feature extractors analyze the segments in a .seg file and output a features file containing one or more values representing the features found. Some feature extractors, like ChunkPower, simply put out one number representing the total power in each segment. Others, like AvgChroma, put out an array of values for each segment. For a short description of each feature extractor, hover above the feature extractor's name and a tooltip will pop up.
You can select as many feature extractors as you like, although best results are usually obtained by selecting features extractors that work well with the composers you'll feed the .feat file to. The number box beside each feature extractor is for entering weights that allow you to specify the relative importance of each feature in the analysis.
"Meta feature extractors" are a special class of FEs that do higher level analysis on the outputs of previously run "normal" feature extractors. In order to use a meta feature extractor, you need to select at least one normal feature extractor in addition to the meta feature extractor. If "clear non-meta features" is selected, the output features file will only contain the selected meta features.
The "Display extracted features" button is enabled after processing a segments file. It pops up a window with a simple viewer that allows you to inspect the values of the extracted features. This is useful if you need to set value ranges in a Composer.
Available feature extractors:
A composer takes a feature file as an input, analyzes/sorts/modifys the segments in that file, and then creates an Edit Decision List (EDL) representing the order in which the segments from the original source sound file (as well as others) should be arranged by the Synthesizer. Composers can be very simple or very complex. For example, "simple sort" simply sorts a features file by the first feature in each chunk. You could use this with AvgPitchSimple to generate a glissando where all of the pitches in the input sound are arranged from low to high. More complex Composers, like "MashUp" and "head bang" perform more sophisticated operations.
Each composer is described by a short text that appears when you select it. The controls for that composer (if any) will appear below the text.
Controls: Each composer's controls (if any) are different, and should be described in that composer's explanatory text. The following Universal Chunk Operations apply to all composers.
The "Display composed features" button is like the "Display extracted features" button above, but it works on the newly composed EDL file. This is convenient for inspecting the results of the composer. For instance, if you run the "simple sort" composer and display the EDL file you will see that the jumpy colors in the .feat file have been turned into a smooth fade in the sorted EDL.
The Synthesizer uses the EDL from a composer to construct a new audio file. The output sound file name is automatically set to the input sound file name + MEAPED.wav. You can change this if you like. Once the new audio file has been created the "Listen" button will be active. Clicking on the button will launch your preferred .wav playback application.
System wide preferences are set here.
The Visualizer presents data from .feat and .edl files in a variety of graphical formats. Mouse over a chunk to inspect its data in the "chunk data" frame on the left side of the screen. Click on chunks to select/deselect. Click and drag to select regions. Shift + click to add to selection.
The available visualizers are: