node-av / lib / avMulQ

Function: avMulQ()

avMulQ(a, b): IRational

Defined in: src/lib/utilities.ts:922

Multiply two rational numbers.

Multiplies two rational numbers using FFmpeg's av_mul_q() which normalizes the result. This is more accurate than manual multiplication as it reduces the fraction.

Direct mapping to av_mul_q().

Parameters

a

IRational

First rational number

b

IRational

Second rational number

Returns

IRational

Product of a and b as a normalized rational

Example

// Multiply framerate by 2
const framerate = { num: 25, den: 1 };
const doubled = avMulQ(framerate, { num: 2, den: 1 });
// Returns { num: 50, den: 1 }

// Calculate field rate for interlaced video
const fieldRate = avMulQ(framerate, { num: 2, den: 1 });

See

av_mul_q - FFmpeg Doxygen