NodeAV

node-av / lib / avInvQ

Function: avInvQ() ​

avInvQ(q): IRational

Defined in: src/lib/utilities.ts:981

Invert a rational number.

Returns the reciprocal of a rational number using FFmpeg's av_inv_q(). Swaps numerator and denominator: (a/b) becomes (b/a).

Direct mapping to av_inv_q().

Parameters ​

q ​

IRational

Rational number to invert

Returns ​

IRational

Inverted rational (reciprocal)

Example ​

typescript
// Convert framerate to frame duration
const framerate = { num: 25, den: 1 };  // 25 fps
const frameDuration = avInvQ(framerate); // 1/25 seconds
// Returns { num: 1, den: 25 }

// Get timebase from framerate
const timebase = avInvQ({ num: 30000, den: 1001 }); // NTSC
// Returns { num: 1001, den: 30000 }

See ​

av_inv_q - FFmpeg Doxygen