import { VideoTranscodingFPS } from './video-transcoding-fps.model'
-export enum VideoResolution {
+export const enum VideoResolution {
H_NOVIDEO = 0,
H_240P = 240,
H_360P = 360,
H_480P = 480,
H_720P = 720,
H_1080P = 1080,
+ H_1440P = 1440,
H_4K = 2160
}
* Google Live Encoder: https://support.google.com/youtube/answer/2853702?hl=en
* YouTube Video Info: youtube-dl --list-formats, with sample videos
*/
-function getBaseBitrate (resolution: VideoResolution) {
- switch (resolution) {
- case VideoResolution.H_NOVIDEO:
- // audio-only
- return 64 * 1000
+function getBaseBitrate (resolution: number) {
+ if (resolution === VideoResolution.H_NOVIDEO) {
+ // audio-only
+ return 64 * 1000
+ }
- case VideoResolution.H_240P:
- // quality according to Google Live Encoder: 300 - 700 Kbps
- // Quality according to YouTube Video Info: 285 Kbps
- return 320 * 1000
+ if (resolution <= VideoResolution.H_240P) {
+ // quality according to Google Live Encoder: 300 - 700 Kbps
+ // Quality according to YouTube Video Info: 285 Kbps
+ return 320 * 1000
+ }
- case VideoResolution.H_360P:
- // quality according to Google Live Encoder: 400 - 1,000 Kbps
- // Quality according to YouTube Video Info: 700 Kbps
- return 780 * 1000
+ if (resolution <= VideoResolution.H_360P) {
+ // quality according to Google Live Encoder: 400 - 1,000 Kbps
+ // Quality according to YouTube Video Info: 700 Kbps
+ return 780 * 1000
+ }
- case VideoResolution.H_480P:
- // quality according to Google Live Encoder: 500 - 2,000 Kbps
- // Quality according to YouTube Video Info: 1300 Kbps
- return 1500 * 1000
+ if (resolution <= VideoResolution.H_480P) {
+ // quality according to Google Live Encoder: 500 - 2,000 Kbps
+ // Quality according to YouTube Video Info: 1300 Kbps
+ return 1500 * 1000
+ }
- case VideoResolution.H_720P:
- // quality according to Google Live Encoder: 1,500 - 4,000 Kbps
- // Quality according to YouTube Video Info: 2680 Kbps
- return 2800 * 1000
+ if (resolution <= VideoResolution.H_720P) {
+ // quality according to Google Live Encoder: 1,500 - 4,000 Kbps
+ // Quality according to YouTube Video Info: 2680 Kbps
+ return 2800 * 1000
+ }
- case VideoResolution.H_1080P:
- // quality according to Google Live Encoder: 3000 - 6000 Kbps
- // Quality according to YouTube Video Info: 5081 Kbps
- return 5200 * 1000
+ if (resolution <= VideoResolution.H_1080P) {
+ // quality according to Google Live Encoder: 3000 - 6000 Kbps
+ // Quality according to YouTube Video Info: 5081 Kbps
+ return 5200 * 1000
+ }
- case VideoResolution.H_4K: // fallthrough
- default:
- // quality according to Google Live Encoder: 13000 - 34000 Kbps
- return 22000 * 1000
+ if (resolution <= VideoResolution.H_1440P) {
+ // quality according to Google Live Encoder: 6000 - 13000 Kbps
+ // Quality according to YouTube Video Info: 8600 (av01) - 17000 (vp9.2) Kbps
+ return 10_000 * 1000
}
+
+ // 4K
+ // quality according to Google Live Encoder: 13000 - 34000 Kbps
+ return 22_000 * 1000
}
/**
* getBaseBitrate() * 1.4. All other values are calculated linearly
* between these two points.
*/
-export function getTargetBitrate (resolution: VideoResolution, fps: number, fpsTranscodingConstants: VideoTranscodingFPS) {
+export function getTargetBitrate (resolution: number, fps: number, fpsTranscodingConstants: VideoTranscodingFPS) {
const baseBitrate = getBaseBitrate(resolution)
// The maximum bitrate, used when fps === VideoTranscodingFPS.MAX
// Based on numbers from Youtube, 60 fps bitrate divided by 30 fps bitrate:
// Example outputs:
// 1080p10: 2420 kbps, 1080p30: 3300 kbps, 1080p60: 4620 kbps
// 720p10: 1283 kbps, 720p30: 1750 kbps, 720p60: 2450 kbps
- return baseBitrate + (fps - fpsTranscodingConstants.AVERAGE) * (maxBitrateDifference / maxFpsDifference)
+ return Math.floor(baseBitrate + (fps - fpsTranscodingConstants.AVERAGE) * (maxBitrateDifference / maxFpsDifference))
}
/**