Key based on distance from a luminance value The jit.lumakey object measures the chromatic distance of each of the left input's cells (pixels) with a reference luminance calulated by the formula lum = (ascale * alpha_value) + (rscale * r_value) + (gscale * g_value) + (bscale * b_value). Cycling '74 Jitter Jitter Compositing in TEXT_HERE in2 TEXT_HERE out TEXT_HERE dumpout TEXT_HERE char long float32 float64 char long float32 float64 Alpha scaling factor The alpha scaling factor (default = 0.) Blue scaling factor The blue scaling factor (default = 0.114) Amount of fade Amount of fade (default = 0.) Green scaling factor (default = 0.587) The green scaling factor (default = 0.587) Reference luminance (default = all 0.) The reference luminance (default = all 0.) Maximum keying value The maximum keying (maxkey) value (default = 1.) Minimum keying value The minimum keying (minkey) value (default = 0.) Output mode Output mode (default = 0 (output keyed matrix))
0 = perform keying and output matrix
1 = output the key map for use elsewhere
2 = alpha contains key map, other planes are from left input TEXT_HERE TEXT_HERE TEXT_HERE TEXT_HERE TEXT_HERE TEXT_HERE Red scaling factor The red scaling factor (default = 0.299) Tolerated distance The tolerated distance (tol) -- the range of variance from which an input cell's absolute value can diverge when calculating keying (default = 0.)

If the distance is less than or equal to a tolerated distance (tol) value, the right input cell is multiplied by a maximum keying (maxkey) value.

If the distance is greater than the tolerated distance but less than the sum of the tolerated value and a set fade value (fade) an interpolated value between the some value between minkey and maxkey values is applied.

For values whose distance is greater than the sum of the tolerated and fade values, the right input cell is multiplied by the minkey value.

The left input is always multiplied by the additive inverse of the left input's multiplicand.

The jit.lumakey object has two modes of output; the first keys between the two input sources, and the second mode will output the keying values (i.e., the left input multiplicands) rather than applying the keying -- the left input is ignored. This is useful for outputting keying information for use with other Jitter objects. Keying can be inverted by swapping the minkey and maxkey values.