colour of magic

COLOUR OF MAGIC — a multi-colorspace video PROCESSOR. One video IN runs through FIVE parallel colorspace blocks — RGB, YDbDr (the SECAM luma+chroma broadcast space), HSV-or-HSL, YIQ (the NTSC composite space, its orange↔cyan flesh-tone I axis + green↔magenta Q axis), and YCbCr BT.601 STUDIO-SWING (the broadcast-legal 16–235 / 16–240 window whose ~1.16× decode expansion CRUSHES super-black/white like a proc-amp) — each block encoding the picture into that space, adjusting each component, then decoding back to RGB. Every block has, per channel: a BIAS knob (additive offset, identity at 0) that also sums CV patched into its cv input; a MONO OVERRIDE input that REPLACES that channel with an incoming grayscale/video stream (bias still adds on top, so a patched key can still be offset); and an OVER/CLAMP toggle — CLAMP clips out-of-range to 0..1 (a legal clip) while OVER wraps it around via fract() (the LZX chroma-wrap look where over-driven values fold back through the spectrum). Bipolar chroma rides a 0.5 pedestal (YDbDr Db/Dr, YIQ I/Q) or the authentic 128/255 = 0.502 pedestal (studio-swing Cb/Cr); HUE always wraps regardless of its toggle (which is advisory). The third block switches HSV↔HSL. TWENTY-TWO outputs run in parallel: pass (the untouched source); rgb / ydbdr / hsvhsl / yiq / ycc (each block colorized); and per-block grayscale channel taps — r / g / b / luma (RGB), ydb_y/db/dr (YDbDr), hsv_h/s/v (HSV·HSL), yiq_y/i/q (YIQ, its mono I tap a ready-made warmth/skin key), ycc_y/cb/cr (studio-swing). The RGB block also has a palette REPLACE mode: three colour-picker swatches remap the adjusted R/G/B channels to chosen output colours (a duotone/tritone recolour) before the rgb out — picking a swatch auto-enables REPLACE and the swatches default to a non-identity teal/orange/violet so it recolours immediately. Only the outputs you PATCH downstream (plus the one you PREVIEW) are rendered each frame, so the many taps stay cheap. With nothing patched all outputs are opaque black. All colorspace math is a 1:1 mirror of the pure, unit-tested $lib/video/colourofmagic-colorspace core. The card has a live preview (with a 22-way output selector), the five block columns of knobs + OVER/CLAMP pills, the HSV/HSL toggle, and the palette REPLACE swatches; all CV + mono-override jacks + the 22 outputs live in the sectioned yellow drill-down PATCH PANEL (IN / RGB / YDbDr / HSV-HSL / YIQ / YCbCr / OUT, no raw side jacks).

COLOUR OF MAGIC is a multi-colorspace video processor. It takes ONE video input and runs it through FIVE parallel colorspace blocks at once — RGB, YDbDr (the SECAM broadcast luma+chroma space), HSV-or-HSL, YIQ (the NTSC composite space), and YCbCr BT.601 STUDIO-SWING (the broadcast-legal 16–235 / 16–240 quantization) — each block encoding the picture into that space, adjusting each component, then decoding back to RGB. Every block has, per channel: a BIAS knob (additive offset, identity at 0) that also sums any CV patched into its cv input; a MONO OVERRIDE input that REPLACES that channel's value with an incoming grayscale/video stream (bias still adds on top, so a patched key can still be offset); and an OVER/CLAMP toggle that decides what happens out of range — CLAMP clips to 0..1 (a legal, safe clip) while OVER wraps it around (fract(), the LZX chroma-wrap look where over-driven values fold back through the spectrum). Chroma components ride on a 0.5 pedestal (YDbDr Db/Dr, YIQ I/Q) or the authentic 128/255 = 0.502 pedestal (studio-swing Cb/Cr) so a bias pushes the colour-difference axes symmetrically; HUE always wraps regardless of the toggle. The third block switches between HSV and HSL with the HSL toggle. YIQ rotates the colour-difference plane onto the orange↔cyan flesh-tone (I) and green↔magenta (Q) axes — one I bias is a whole teal-&-orange grade. Studio-swing compresses into the legal window and decode expands it ~1.16×, so a bias CRUSHES super-black/white the way a proc-amp / legalizer does. TWENTY-TWO outputs run in parallel: pass (the untouched source); rgb / ydbdr / hsvhsl / yiq / ycc (each block's colorized picture); and per-block grayscale channel taps — r / g / b / luma (RGB), ydb_y/db/dr (YDbDr), hsv_h/s/v (HSV·HSL), yiq_y/i/q (YIQ), ycc_y/cb/cr (studio-swing). The mono taps emit the adjusted packed channel as grayscale — a mono I tap is a ready-made skin/warmth key; a hue tap has a hard black↔white seam at hue 0≡1 (the correct grayscale image of a circular quantity). The RGB block additionally has a palette REPLACE mode: three colour swatches remap the adjusted R/G/B channels to chosen output colours (a duotone/tritone recolour) before the rgb output; picking a swatch auto-enables REPLACE and the swatches default to a non-identity teal/orange/violet so the recolour is immediately visible. With no input patched all outputs are opaque black. Only the outputs you PATCH downstream (plus the one you PREVIEW on the card) are actually rendered each frame, so the many taps stay cheap. Patch a source into IN, choose which output to preview on the card, and use the block knobs / channel overrides / palette to recolour, split, or key the picture.

the faceplate

inputs

outputs

params

controls

source

colourofmagic.ts on GitHub.