@remotion/media-parser
Version:
A pure JavaScript library for parsing video files
75 lines (74 loc) • 3.41 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.handleAacPacket = void 0;
const aac_codecprivate_1 = require("../../aac-codecprivate");
const convert_audio_or_video_sample_1 = require("../../convert-audio-or-video-sample");
const register_track_1 = require("../../register-track");
const webcodecs_timescale_1 = require("../../webcodecs-timescale");
const adts_header_1 = require("./adts-header");
const handle_avc_packet_1 = require("./handle-avc-packet");
const handleAacPacket = async ({ streamBuffer, programId, offset, sampleCallbacks, logLevel, onAudioTrack, transportStream, makeSamplesStartAtZero, }) => {
var _a, _b;
const adtsHeader = (0, adts_header_1.readAdtsHeader)(streamBuffer.getBuffer());
if (!adtsHeader) {
throw new Error('Invalid ADTS header - too short');
}
const { channelConfiguration, codecPrivate, sampleRate, audioObjectType } = adtsHeader;
const isTrackRegistered = sampleCallbacks.tracks.getTracks().find((t) => {
return t.trackId === programId;
});
if (!isTrackRegistered) {
const startOffset = makeSamplesStartAtZero
? Math.min(streamBuffer.pesHeader.pts, (_a = streamBuffer.pesHeader.dts) !== null && _a !== void 0 ? _a : Infinity)
: 0;
transportStream.startOffset.setOffset({
trackId: programId,
newOffset: startOffset,
});
const track = {
type: 'audio',
codecData: { type: 'aac-config', data: codecPrivate },
trackId: programId,
originalTimescale: handle_avc_packet_1.MPEG_TIMESCALE,
codecEnum: 'aac',
codec: (0, aac_codecprivate_1.mapAudioObjectTypeToCodecString)(audioObjectType),
// https://www.w3.org/TR/webcodecs-aac-codec-registration/
// WebCodecs spec says that description should be given for AAC format
// ChatGPT says that Transport Streams are always AAC, not ADTS
description: codecPrivate,
numberOfChannels: channelConfiguration,
sampleRate,
startInSeconds: 0,
timescale: webcodecs_timescale_1.WEBCODECS_TIMESCALE,
trackMediaTimeOffsetInTrackTimescale: 0,
};
await (0, register_track_1.registerAudioTrack)({
track,
container: 'transport-stream',
registerAudioSampleCallback: sampleCallbacks.registerAudioSampleCallback,
tracks: sampleCallbacks.tracks,
logLevel,
onAudioTrack,
});
}
const sample = {
decodingTimestamp: ((_b = streamBuffer.pesHeader.dts) !== null && _b !== void 0 ? _b : streamBuffer.pesHeader.pts) -
transportStream.startOffset.getOffset(programId),
timestamp: streamBuffer.pesHeader.pts -
transportStream.startOffset.getOffset(programId),
duration: undefined,
data: streamBuffer.getBuffer(),
type: 'key',
offset,
};
const audioSample = (0, convert_audio_or_video_sample_1.convertAudioOrVideoSampleToWebCodecsTimestamps)({
sample,
timescale: handle_avc_packet_1.MPEG_TIMESCALE,
});
await sampleCallbacks.onAudioSample({
audioSample,
trackId: programId,
});
transportStream.lastEmittedSample.setLastEmittedSample(sample);
};
exports.handleAacPacket = handleAacPacket;