remotion-dev/remotion · error · Error

Invalid sync byte

Error message

Invalid sync byte

What it means

Thrown by parsePacket() when the first byte of a 188-byte MPEG-TS packet is not 0x47 (the MPEG-TS sync byte). Every TS packet must start with 0x47; any other value means the data is not aligned to a TS packet boundary or is not MPEG-TS at all.

Source

Thrown at packages/media-parser/src/containers/transport-stream/parse-packet.ts:23

import {parsePat, parseSdt} from './parse-pat';
import {parsePes} from './parse-pes';
import {parsePmt} from './parse-pmt';
import {parseStream} from './parse-stream-packet';
import {getProgramForId, getStreamForId} from './traversal';

export const parsePacket = ({
	iterator,
	structure,
	transportStream,
}: {
	iterator: BufferIterator;
	structure: TransportStreamStructure;
	transportStream: TransportStreamState;
}): TransportStreamBox | null => {
	const offset = iterator.counter.getOffset();
	const syncByte = iterator.getUint8();
	if (syncByte !== 0x47) {
		throw new Error('Invalid sync byte');
	}

	iterator.startReadingBits();
	iterator.getBits(1); // transport error indicator
	const payloadUnitStartIndicator = iterator.getBits(1);
	iterator.getBits(1); // transport priority
	const programId = iterator.getBits(13);
	iterator.getBits(2); // transport scrambling control
	const adaptationFieldControl1 = iterator.getBits(1); // adaptation field control 1
	iterator.getBits(1); // adaptation field control 2
	iterator.getBits(4); // continuity counter
	iterator.stopReadingBits();
	if (adaptationFieldControl1 === 1) {
		iterator.startReadingBits();
		const adaptationFieldLength = iterator.getBits(8);
		const headerOffset = iterator.counter.getOffset();
		if (adaptationFieldLength > 0) {
			iterator.getBits(1); // discontinuity indicator

View on GitHub (pinned to 78fe4bb3fd)

Solutions

1. Resync by scanning forward for the next 0x47 at a 188-byte stride before parsing.
2. Verify the file is MPEG-TS (ffprobe -show_format).
3. Re-mux the TS to repair alignment: ffmpeg -i in.ts -c copy out.ts.

Example fix

// before
const syncByte = iterator.getUint8();
if (syncByte !== 0x47) throw new Error('Invalid sync byte');

// after: resync to next 0x47
while (iterator.bytesRemaining() > 0 && iterator.getUint8() !== 0x47) { /* advance */ }

// Verify the 0x47 sync byte at each 188-byte boundary before parsing.
function isTsSyncByte(b: number): boolean {
  return b === 0x47;
}
if (!isTsSyncByte(iterator.getUint8())) {
  // resync: scan forward for 0x47 at 188-byte stride
}

function isTsSyncByte(b: number): boolean {
  return b === 0x47;
}

try {
  parsePacket({iterator, structure, transportStream});
} catch (err) {
  if (err instanceof Error && err.message === 'Invalid sync byte') {
    // resync to next 0x47 and continue
  } else throw err;
}

When it happens

Trigger: Misaligned TS data (the reader is not at a packet boundary), corrupt TS, or non-TS data routed to the TS parser. Common after a dropped/corrupt packet throws alignment off by N bytes.

Common situations: See trigger scenarios.

Related errors

• Unknown packet identifier
• Invalid ADTS header
• Only supporting MPEG-4 for .ts
• Only supporting layer 0 for .ts
• Invalid ADTS header - too short

AI-assisted analysis of remotion-dev/remotion@78fe4bb3fd (2026-08-12). Data as JSON: /api/errors/09f02749b78565a5. Report an issue: GitHub.