Function generateAv1CodecString

src/codec_data.ts:1479–1513

(codecInfo: Av1CodecInfo)

const AV1_DEFAULT_SUFFIX = '.0.110.01.01.01.0';

export const generateAv1CodecString = (codecInfo: Av1CodecInfo) => {
	// https://aomediacodec.github.io/av1-isobmff/#codecsparam
	const profile = codecInfo.profile; // Single digit
	const level = codecInfo.level.toString().padStart(2, '0');
	const tier = codecInfo.tier ? 'H' : 'M';
	const bitDepth = codecInfo.bitDepth.toString().padStart(2, '0');
	const monochrome = codecInfo.monochrome ? '1' : '0';
	const chromaSubsampling = 100 * codecInfo.chromaSubsamplingX
		+ 10 * codecInfo.chromaSubsamplingY
		+ 1 * (
			codecInfo.chromaSubsamplingX && codecInfo.chromaSubsamplingY
				? codecInfo.chromaSamplePosition
				: 0
		);

	// The defaults are 1 (ITU-R BT.709)
	const colorPrimaries = 1;
	const transferCharacteristics = 1;
	const matrixCoefficients = 1;

	const videoFullRangeFlag = 0;

	let string = `av01.${profile}.${level}${tier}.${bitDepth}`;
	string += `.${monochrome}.${chromaSubsampling.toString().padStart(3, '0')}`;
	string += `.${colorPrimaries.toString().padStart(2, '0')}`;
	string += `.${transferCharacteristics.toString().padStart(2, '0')}`;
	string += `.${matrixCoefficients.toString().padStart(2, '0')}`;
	string += `.${videoFullRangeFlag}`;

	if (string.endsWith(AV1_DEFAULT_SUFFIX)) {
		string = string.slice(0, -AV1_DEFAULT_SUFFIX.length);
	}

	return string;
};

export type AacAudioSpecificConfig = {
	objectType: number;