From 4d127a038bf768eded68aae3cfa5c1b12241bdac Mon Sep 17 00:00:00 2001 From: Maze Winther Date: Fri, 27 Mar 2026 00:55:15 +0100 Subject: chore: normalize line endings --- apps/web/src/lib/retime/audio-stretch.ts | 364 +++++++++++++++---------------- 1 file changed, 182 insertions(+), 182 deletions(-) (limited to 'apps/web/src/lib/retime/audio-stretch.ts') diff --git a/apps/web/src/lib/retime/audio-stretch.ts b/apps/web/src/lib/retime/audio-stretch.ts index 51ef38d0..f8dd297c 100644 --- a/apps/web/src/lib/retime/audio-stretch.ts +++ b/apps/web/src/lib/retime/audio-stretch.ts @@ -1,182 +1,182 @@ -import { PitchShifter } from "soundtouchjs"; -import { clampRetimeRate, shouldMaintainPitch } from "@/constants/retime-constants"; -import type { RetimeConfig } from "@/lib/timeline"; -import { getSourceTimeAtClipTime } from "./resolve"; - -const RATE_EPSILON = 1e-6; - -function sampleLinear({ - channelData, - position, -}: { - channelData: Float32Array; - position: number; -}): number { - if (position <= 0) { - return channelData[0] ?? 0; - } - const lower = Math.floor(position); - const upper = Math.min(channelData.length - 1, lower + 1); - if (lower >= channelData.length) { - return 0; - } - const fraction = position - lower; - return channelData[lower] * (1 - fraction) + channelData[upper] * fraction; -} - -function buildResampledBuffer({ - audioContext, - sourceBuffer, - trimStart, - clipDuration, - targetSampleRate, - retime, -}: { - audioContext: BaseAudioContext; - sourceBuffer: AudioBuffer; - trimStart: number; - clipDuration: number; - targetSampleRate: number; - retime?: RetimeConfig; -}): AudioBuffer { - const outputLength = Math.max(1, Math.ceil(clipDuration * targetSampleRate)); - const numChannels = Math.max(1, Math.min(2, sourceBuffer.numberOfChannels)); - const outputBuffer = audioContext.createBuffer( - numChannels, - outputLength, - targetSampleRate, - ); - - for (let channel = 0; channel < numChannels; channel++) { - const sourceData = sourceBuffer.getChannelData( - Math.min(channel, sourceBuffer.numberOfChannels - 1), - ); - const outputData = outputBuffer.getChannelData(channel); - - for (let i = 0; i < outputLength; i++) { - const clipTime = i / targetSampleRate; - const sourceTime = - trimStart + getSourceTimeAtClipTime({ clipTime, retime }); - outputData[i] = sampleLinear({ - channelData: sourceData, - position: sourceTime * sourceBuffer.sampleRate, - }); - } - } - - return outputBuffer; -} - -async function buildPitchPreservedBuffer({ - sourceBuffer, - trimStart, - clipDuration, - rate, - targetSampleRate, -}: { - sourceBuffer: AudioBuffer; - trimStart: number; - clipDuration: number; - rate: number; - targetSampleRate: number; -}): Promise { - const nativeSampleRate = sourceBuffer.sampleRate; - const sourceDuration = clipDuration * rate; - const startSample = Math.max(0, Math.floor(trimStart * nativeSampleRate)); - const numSourceSamples = Math.max( - 1, - Math.ceil(sourceDuration * nativeSampleRate), - ); - const available = Math.max(0, sourceBuffer.length - startSample); - const actualSamples = Math.max(1, Math.min(numSourceSamples, available)); - const numChannels = Math.max(1, Math.min(2, sourceBuffer.numberOfChannels)); - - // Resample to targetSampleRate first — soundtouchjs reads raw channel data - // and does not respect the source buffer's native sample rate. - const resampledLength = Math.max( - 1, - Math.ceil(sourceDuration * targetSampleRate), - ); - const resampleCtx = new OfflineAudioContext( - numChannels, - resampledLength, - targetSampleRate, - ); - const nativeBuffer = resampleCtx.createBuffer( - numChannels, - actualSamples, - nativeSampleRate, - ); - - for (let ch = 0; ch < numChannels; ch++) { - const src = sourceBuffer.getChannelData( - Math.min(ch, sourceBuffer.numberOfChannels - 1), - ); - nativeBuffer.copyToChannel( - src.subarray(startSample, startSample + actualSamples), - ch, - ); - } - - const resampleSourceNode = resampleCtx.createBufferSource(); - resampleSourceNode.buffer = nativeBuffer; - resampleSourceNode.connect(resampleCtx.destination); - resampleSourceNode.start(0); - const resampledBuffer = await resampleCtx.startRendering(); - - const outputSamples = Math.max( - 1, - Math.ceil(clipDuration * targetSampleRate), - ); - const stretchCtx = new OfflineAudioContext( - numChannels, - outputSamples, - targetSampleRate, - ); - const shifter = new PitchShifter(stretchCtx, resampledBuffer, 4096); - shifter.tempo = rate; - shifter.pitch = 1; - shifter.connect(stretchCtx.destination); - return stretchCtx.startRendering(); -} - -export async function renderRetimedBuffer({ - audioContext, - sourceBuffer, - trimStart, - clipDuration, - retime, - maintainPitch = false, -}: { - audioContext: BaseAudioContext; - sourceBuffer: AudioBuffer; - trimStart: number; - clipDuration: number; - retime?: RetimeConfig; - maintainPitch?: boolean; -}): Promise { - const targetSampleRate = audioContext.sampleRate; - const rate = clampRetimeRate({ rate: retime?.rate ?? 1 }); - const usePitchPreservation = - shouldMaintainPitch({ rate, maintainPitch }) && - Math.abs(rate - 1) > RATE_EPSILON; - - if (usePitchPreservation) { - return buildPitchPreservedBuffer({ - sourceBuffer, - trimStart, - clipDuration, - rate, - targetSampleRate, - }); - } - - return buildResampledBuffer({ - audioContext, - sourceBuffer, - trimStart, - clipDuration, - targetSampleRate, - retime, - }); -} +import { PitchShifter } from "soundtouchjs"; +import { clampRetimeRate, shouldMaintainPitch } from "@/constants/retime-constants"; +import type { RetimeConfig } from "@/lib/timeline"; +import { getSourceTimeAtClipTime } from "./resolve"; + +const RATE_EPSILON = 1e-6; + +function sampleLinear({ + channelData, + position, +}: { + channelData: Float32Array; + position: number; +}): number { + if (position <= 0) { + return channelData[0] ?? 0; + } + const lower = Math.floor(position); + const upper = Math.min(channelData.length - 1, lower + 1); + if (lower >= channelData.length) { + return 0; + } + const fraction = position - lower; + return channelData[lower] * (1 - fraction) + channelData[upper] * fraction; +} + +function buildResampledBuffer({ + audioContext, + sourceBuffer, + trimStart, + clipDuration, + targetSampleRate, + retime, +}: { + audioContext: BaseAudioContext; + sourceBuffer: AudioBuffer; + trimStart: number; + clipDuration: number; + targetSampleRate: number; + retime?: RetimeConfig; +}): AudioBuffer { + const outputLength = Math.max(1, Math.ceil(clipDuration * targetSampleRate)); + const numChannels = Math.max(1, Math.min(2, sourceBuffer.numberOfChannels)); + const outputBuffer = audioContext.createBuffer( + numChannels, + outputLength, + targetSampleRate, + ); + + for (let channel = 0; channel < numChannels; channel++) { + const sourceData = sourceBuffer.getChannelData( + Math.min(channel, sourceBuffer.numberOfChannels - 1), + ); + const outputData = outputBuffer.getChannelData(channel); + + for (let i = 0; i < outputLength; i++) { + const clipTime = i / targetSampleRate; + const sourceTime = + trimStart + getSourceTimeAtClipTime({ clipTime, retime }); + outputData[i] = sampleLinear({ + channelData: sourceData, + position: sourceTime * sourceBuffer.sampleRate, + }); + } + } + + return outputBuffer; +} + +async function buildPitchPreservedBuffer({ + sourceBuffer, + trimStart, + clipDuration, + rate, + targetSampleRate, +}: { + sourceBuffer: AudioBuffer; + trimStart: number; + clipDuration: number; + rate: number; + targetSampleRate: number; +}): Promise { + const nativeSampleRate = sourceBuffer.sampleRate; + const sourceDuration = clipDuration * rate; + const startSample = Math.max(0, Math.floor(trimStart * nativeSampleRate)); + const numSourceSamples = Math.max( + 1, + Math.ceil(sourceDuration * nativeSampleRate), + ); + const available = Math.max(0, sourceBuffer.length - startSample); + const actualSamples = Math.max(1, Math.min(numSourceSamples, available)); + const numChannels = Math.max(1, Math.min(2, sourceBuffer.numberOfChannels)); + + // Resample to targetSampleRate first — soundtouchjs reads raw channel data + // and does not respect the source buffer's native sample rate. + const resampledLength = Math.max( + 1, + Math.ceil(sourceDuration * targetSampleRate), + ); + const resampleCtx = new OfflineAudioContext( + numChannels, + resampledLength, + targetSampleRate, + ); + const nativeBuffer = resampleCtx.createBuffer( + numChannels, + actualSamples, + nativeSampleRate, + ); + + for (let ch = 0; ch < numChannels; ch++) { + const src = sourceBuffer.getChannelData( + Math.min(ch, sourceBuffer.numberOfChannels - 1), + ); + nativeBuffer.copyToChannel( + src.subarray(startSample, startSample + actualSamples), + ch, + ); + } + + const resampleSourceNode = resampleCtx.createBufferSource(); + resampleSourceNode.buffer = nativeBuffer; + resampleSourceNode.connect(resampleCtx.destination); + resampleSourceNode.start(0); + const resampledBuffer = await resampleCtx.startRendering(); + + const outputSamples = Math.max( + 1, + Math.ceil(clipDuration * targetSampleRate), + ); + const stretchCtx = new OfflineAudioContext( + numChannels, + outputSamples, + targetSampleRate, + ); + const shifter = new PitchShifter(stretchCtx, resampledBuffer, 4096); + shifter.tempo = rate; + shifter.pitch = 1; + shifter.connect(stretchCtx.destination); + return stretchCtx.startRendering(); +} + +export async function renderRetimedBuffer({ + audioContext, + sourceBuffer, + trimStart, + clipDuration, + retime, + maintainPitch = false, +}: { + audioContext: BaseAudioContext; + sourceBuffer: AudioBuffer; + trimStart: number; + clipDuration: number; + retime?: RetimeConfig; + maintainPitch?: boolean; +}): Promise { + const targetSampleRate = audioContext.sampleRate; + const rate = clampRetimeRate({ rate: retime?.rate ?? 1 }); + const usePitchPreservation = + shouldMaintainPitch({ rate, maintainPitch }) && + Math.abs(rate - 1) > RATE_EPSILON; + + if (usePitchPreservation) { + return buildPitchPreservedBuffer({ + sourceBuffer, + trimStart, + clipDuration, + rate, + targetSampleRate, + }); + } + + return buildResampledBuffer({ + audioContext, + sourceBuffer, + trimStart, + clipDuration, + targetSampleRate, + retime, + }); +} -- cgit v1.3.1