From 001f152eeca7e53a3d1069f01bab6e6114bd118c Mon Sep 17 00:00:00 2001
From: infrost <hx.zeng@hotmail.com>
Date: Wed, 8 Jul 2026 02:37:13 +0100
Subject: [PATCH] =?UTF-8?q?Parallel=20QR=20=E9=BB=98=E8=AE=A4=E6=94=B9?=
 =?UTF-8?q?=E6=88=90=204=EF=BC=8C=E9=80=89=E9=A1=B9=E6=89=A9=E5=88=B0=201/?=
 =?UTF-8?q?2/4/6/8=EF=BC=8Clive=20=E5=92=8C=20GIF=20=E5=B8=83=E5=B1=80?=
 =?UTF-8?q?=E9=83=BD=E6=94=AF=E6=8C=81=206=20=3D=203x2=E3=80=818=20=3D=204?=
 =?UTF-8?q?x2=E3=80=82=20Sender=20=E9=87=8C=20QR=20encoder=E3=80=81FEC=20c?=
 =?UTF-8?q?odec=E3=80=81RaptorQ=20repair=20=E9=83=BD=E6=94=B6=E8=BF=9B?=
 =?UTF-8?q?=E4=BA=86=20Advanced=20settings=E3=80=82=20RaptorQ=20repair=20?=
 =?UTF-8?q?=E9=BB=98=E8=AE=A4=E4=BB=8E=2020%=20=E6=94=B9=E6=88=90=2010%?=
 =?UTF-8?q?=E3=80=82=20Receiver=20=E7=9A=84=20Max=20symbols=20=E7=8E=B0?=
 =?UTF-8?q?=E5=9C=A8=E6=98=BE=E7=A4=BA=E4=B8=BA=20Auto=20(4)=EF=BC=8C?=
 =?UTF-8?q?=E5=B9=B6=E4=B8=94=E6=89=8B=E5=8A=A8=E6=94=AF=E6=8C=81=206/8?=
 =?UTF-8?q?=E3=80=82=20Sender=20=E9=80=89=206/8=20=E6=97=B6=E4=BC=9A?=
 =?UTF-8?q?=E6=8F=90=E7=A4=BA=EF=BC=9AReceiver=20=E7=9A=84=20Auto=20(4)=20?=
 =?UTF-8?q?=E5=8F=AA=E6=89=AB=204=20=E4=B8=AA=EF=BC=8C=E9=9C=80=E8=A6=81?=
 =?UTF-8?q?=E6=89=8B=E5=8A=A8=E6=8A=8A=20Max=20symbols=20=E8=AE=BE?=
 =?UTF-8?q?=E6=88=90=E5=AF=B9=E5=BA=94=E7=9A=84=206/8=E3=80=82=20=E4=BF=AE?=
 =?UTF-8?q?=E4=BA=86=20fast=5Fqr=20=E5=AE=B9=E9=87=8F=EF=BC=9A=E5=8F=AA?=
 =?UTF-8?q?=E6=9C=89=20ZXing=20WASM=20=E7=BB=A7=E7=BB=AD=E6=89=A3=E9=82=A3?=
 =?UTF-8?q?=202=20bytes=EF=BC=8Cfast=5Fqr=20WASM=20=E5=92=8C=20JS=20QR=20?=
 =?UTF-8?q?=E9=83=BD=E4=BD=BF=E7=94=A8=E5=AE=8C=E6=95=B4=20QR=20byte=20cap?=
 =?UTF-8?q?acity=E3=80=82=20=E9=A1=BA=E6=89=8B=E4=BF=AE=E4=BA=86=20normali?=
 =?UTF-8?q?zeFecCodec('js-rlnc')=20=E4=BC=9A=E8=A2=AB=E5=BD=92=E5=9B=9E=20?=
 =?UTF-8?q?wasm=20=E9=BB=98=E8=AE=A4=E7=9A=84=E9=97=AE=E9=A2=98=EF=BC=8C?=
 =?UTF-8?q?=E4=B8=8D=E7=84=B6=E9=AB=98=E7=BA=A7=E8=AE=BE=E7=BD=AE=E9=87=8C?=
 =?UTF-8?q?=E7=9A=84=20JS=20compatible=20=E4=BC=9A=E9=80=89=E4=B8=8D?=
 =?UTF-8?q?=E4=BD=8F=E3=80=82?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/app/routes/receiver.tsx          |   6 +-
 src/app/routes/sender.tsx            | 138 ++++++++++++++++-----------
 src/core/fec/codec.ts                |   7 +-
 src/core/protocol/profiles.ts        |  10 +-
 src/core/qr/decode_settings.ts       |   4 +-
 src/core/qr/qr_decode.ts             |   3 +-
 src/core/sender/parallel_striping.ts |   2 +-
 src/tests/test_qr_modules.test.ts    |  52 +++++++++-
 src/workers/gif.worker.ts            |   6 +-
 9 files changed, 150 insertions(+), 78 deletions(-)

diff --git a/src/app/routes/receiver.tsx b/src/app/routes/receiver.tsx
index 47f50d7..a322ab2 100644
--- a/src/app/routes/receiver.tsx
+++ b/src/app/routes/receiver.tsx
@@ -1133,11 +1133,13 @@ function formatDecodePreset(value: DecodePresetId): string {
 function parseMaxSymbolsMode(value: string): MaxSymbolsMode {
   if (value === 'auto') return 'auto';
   const parsed = Number(value);
-  return parsed === 1 || parsed === 2 || parsed === 4 ? parsed : DEFAULT_DECODE_SETTINGS.maxSymbols;
+  return parsed === 1 || parsed === 2 || parsed === 4 || parsed === 6 || parsed === 8
+    ? parsed
+    : DEFAULT_DECODE_SETTINGS.maxSymbols;
 }
 
 function formatMaxSymbols(value: MaxSymbolsMode): string {
-  return value === 'auto' ? 'Auto' : String(value);
+  return value === 'auto' ? 'Auto (4)' : String(value);
 }
 
 function normalizeBinarizer(value: string): QrBinarizer {
diff --git a/src/app/routes/sender.tsx b/src/app/routes/sender.tsx
index f9c41d3..9e2bf7d 100644
--- a/src/app/routes/sender.tsx
+++ b/src/app/routes/sender.tsx
@@ -85,8 +85,8 @@ type CSSProps = Record<string, string | number>;
 const MIN_FRAME_RATE_FPS = 2;
 const MAX_FRAME_RATE_FPS = 60;
 const DEFAULT_FRAME_RATE_FPS = 30;
-const DEFAULT_PARALLEL_QR_COUNT: ParallelQRCount = 1;
-const PARALLEL_QR_COUNTS: ParallelQRCount[] = [1, 2, 4];
+const DEFAULT_PARALLEL_QR_COUNT: ParallelQRCount = 4;
+const PARALLEL_QR_COUNTS: ParallelQRCount[] = [1, 2, 4, 6, 8];
 const FEC_CODEC_OPTIONS: FecCodec[] = ['wasm-raptorq', 'js-rlnc'];
 const LIVE_TARGET_PX = 360;
 const QR_QUIET_ZONE_MODULES = 4;
@@ -258,6 +258,7 @@ export function SenderPage() {
   const [qrEncoder, setQrEncoder] = useState<QREncoder>(DEFAULT_QR_ENCODER);
   const [fecCodec, setFecCodec] = useState<FecCodec>(DEFAULT_FEC_CODEC);
   const [raptorqRepairPercent, setRaptorqRepairPercent] = useState(DEFAULT_RAPTORQ_REPAIR_PERCENT);
+  const [advancedGenerateOpen, setAdvancedGenerateOpen] = useState(false);
   const [frameRateFps, setFrameRateFps] = useState(DEFAULT_FRAME_RATE_FPS);
   const [actualLiveFps, setActualLiveFps] = useState(0);
   const [renderReadyPackets, setRenderReadyPackets] = useState(0);
@@ -1023,63 +1024,76 @@ export function SenderPage() {
           </select>
         </div>
         <div style={{ marginBottom: 16 }}>
-          <div style={{ ...S.row, justifyContent: 'space-between', alignItems: 'baseline' }}>
-            <span style={S.label}>QR encoder</span>
-            <span style={S.infoValue}>{formatQREncoder(qrEncoder)}</span>
-          </div>
-          <select
-            value={qrEncoder}
-            style={S.select}
-            disabled={encodingLive}
-            onChange={(e) => handleQREncoderChange((e.target as HTMLSelectElement).value)}
+          <button
+            type="button"
+            style={S.btnSecondary}
+            onClick={() => setAdvancedGenerateOpen((open) => !open)}
           >
-            {QR_ENCODERS.map((encoder) => (
-              <option key={encoder} value={encoder}>
-                {formatQREncoder(encoder)}
-              </option>
-            ))}
-          </select>
-        </div>
-        <div style={{ marginBottom: 16 }}>
-          <div style={{ ...S.row, justifyContent: 'space-between', alignItems: 'baseline' }}>
-            <span style={S.label}>FEC codec</span>
-            <span style={S.infoValue}>{formatFecCodec(fecCodec)}</span>
-          </div>
-          <select
-            value={fecCodec}
-            style={S.select}
-            disabled={encodingLive}
-            onChange={(e) => handleFecCodecChange((e.target as HTMLSelectElement).value)}
-          >
-            {FEC_CODEC_OPTIONS.map((codec) => (
-              <option key={codec} value={codec}>
-                {formatFecCodec(codec)}
-              </option>
-            ))}
-          </select>
-        </div>
-        {fecCodec === 'wasm-raptorq' && (
-          <div style={{ marginBottom: 16 }}>
-            <div style={{ ...S.row, justifyContent: 'space-between', alignItems: 'baseline' }}>
-              <span style={S.label}>RaptorQ repair</span>
-              <span style={S.infoValue}>{raptorqRepairPercent}%</span>
+            {advancedGenerateOpen ? 'Hide advanced settings' : 'Advanced settings'}
+          </button>
+          {advancedGenerateOpen && (
+            <div style={{ marginTop: 14, display: 'grid', gap: 16 }}>
+              <label>
+                <div style={{ ...S.row, justifyContent: 'space-between', alignItems: 'baseline' }}>
+                  <span style={S.label}>QR encoder</span>
+                  <span style={S.infoValue}>{formatQREncoder(qrEncoder)}</span>
+                </div>
+                <select
+                  value={qrEncoder}
+                  style={S.select}
+                  disabled={encodingLive}
+                  onChange={(e) => handleQREncoderChange((e.target as HTMLSelectElement).value)}
+                >
+                  {QR_ENCODERS.map((encoder) => (
+                    <option key={encoder} value={encoder}>
+                      {formatQREncoder(encoder)}
+                    </option>
+                  ))}
+                </select>
+              </label>
+              <label>
+                <div style={{ ...S.row, justifyContent: 'space-between', alignItems: 'baseline' }}>
+                  <span style={S.label}>FEC codec</span>
+                  <span style={S.infoValue}>{formatFecCodec(fecCodec)}</span>
+                </div>
+                <select
+                  value={fecCodec}
+                  style={S.select}
+                  disabled={encodingLive}
+                  onChange={(e) => handleFecCodecChange((e.target as HTMLSelectElement).value)}
+                >
+                  {FEC_CODEC_OPTIONS.map((codec) => (
+                    <option key={codec} value={codec}>
+                      {formatFecCodec(codec)}
+                    </option>
+                  ))}
+                </select>
+              </label>
+              {fecCodec === 'wasm-raptorq' && (
+                <label>
+                  <div style={{ ...S.row, justifyContent: 'space-between', alignItems: 'baseline' }}>
+                    <span style={S.label}>RaptorQ repair</span>
+                    <span style={S.infoValue}>{raptorqRepairPercent}%</span>
+                  </div>
+                  <input
+                    type="range"
+                    min={MIN_RAPTORQ_REPAIR_PERCENT}
+                    max={MAX_RAPTORQ_REPAIR_PERCENT}
+                    step={1}
+                    value={raptorqRepairPercent}
+                    style={S.slider}
+                    disabled={encodingLive}
+                    onInput={(e) => handleRaptorQRepairPercentChange((e.target as HTMLInputElement).value)}
+                  />
+                  <div style={S.sliderLabels}>
+                    <span>Less QR</span>
+                    <span>More repair</span>
+                  </div>
+                </label>
+              )}
             </div>
-            <input
-              type="range"
-              min={MIN_RAPTORQ_REPAIR_PERCENT}
-              max={MAX_RAPTORQ_REPAIR_PERCENT}
-              step={1}
-              value={raptorqRepairPercent}
-              style={S.slider}
-              disabled={encodingLive}
-              onInput={(e) => handleRaptorQRepairPercentChange((e.target as HTMLInputElement).value)}
-            />
-            <div style={S.sliderLabels}>
-              <span>Less QR</span>
-              <span>More repair</span>
-            </div>
-          </div>
-        )}
+          )}
+        </div>
         <div style={{ marginBottom: 16 }}>
           <div style={{ ...S.row, justifyContent: 'space-between', alignItems: 'baseline' }}>
             <span style={S.label}>QR speed</span>
@@ -1116,6 +1130,12 @@ export function SenderPage() {
               </option>
             ))}
           </select>
+          {parallelQRCount > 4 && (
+            <div style={S.warn}>
+              Receiver Auto (4) scans up to 4 QR codes per frame. For {parallelQRCount} parallel QR,
+              set Receiver advanced settings - Max symbols to {parallelQRCount}.
+            </div>
+          )}
         </div>
         <div style={S.row}>
           <button
@@ -1502,7 +1522,9 @@ function normalizeFrameIndex(frameIndex: number, frameCount: number): number {
 function getParallelLayout(parallelCount: ParallelQRCount): { columns: number; rows: number } {
   if (parallelCount === 1) return { columns: 1, rows: 1 };
   if (parallelCount === 2) return { columns: 2, rows: 1 };
-  return { columns: 2, rows: 2 };
+  if (parallelCount === 4) return { columns: 2, rows: 2 };
+  if (parallelCount === 6) return { columns: 3, rows: 2 };
+  return { columns: 4, rows: 2 };
 }
 
 function getPacketIndexForDisplayFrame(
diff --git a/src/core/fec/codec.ts b/src/core/fec/codec.ts
index 34a409a..2857580 100644
--- a/src/core/fec/codec.ts
+++ b/src/core/fec/codec.ts
@@ -3,12 +3,15 @@ export type ReceiverFecCodec = 'auto' | FecCodec;
 
 export const DEFAULT_FEC_CODEC: FecCodec = 'wasm-raptorq';
 export const DEFAULT_RECEIVER_FEC_CODEC: ReceiverFecCodec = 'auto';
-export const DEFAULT_RAPTORQ_REPAIR_PERCENT = 20;
+export const DEFAULT_RAPTORQ_REPAIR_PERCENT = 10;
 export const MIN_RAPTORQ_REPAIR_PERCENT = 0;
 export const MAX_RAPTORQ_REPAIR_PERCENT = 100;
 
 export function normalizeFecCodec(value: unknown): FecCodec {
-  return value === 'wasm-raptorq' ? 'wasm-raptorq' : DEFAULT_FEC_CODEC;
+  if (value === 'js-rlnc' || value === 'wasm-raptorq') {
+    return value;
+  }
+  return DEFAULT_FEC_CODEC;
 }
 
 export function normalizeReceiverFecCodec(value: unknown): ReceiverFecCodec {
diff --git a/src/core/protocol/profiles.ts b/src/core/protocol/profiles.ts
index 4524d71..538b08b 100644
--- a/src/core/protocol/profiles.ts
+++ b/src/core/protocol/profiles.ts
@@ -12,7 +12,7 @@ import {
   getMaxZXingWriterByteCapacity,
   type EccLevel,
 } from '@/core/qr/qr_encode';
-import type { QREncoder } from '@/core/qr/qr_encoder';
+import { DEFAULT_QR_ENCODER, type QREncoder } from '@/core/qr/qr_encoder';
 
 export interface QRTransferProfile {
   id: string;
@@ -49,13 +49,13 @@ export const QR_TRANSFER_PROFILES: QRTransferProfile[] = PROFILE_SPECS.map((spec
 export function createQRTransferProfile(
   version: number,
   eccLevel: EccLevel,
-  qrEncoder: QREncoder = 'zxing-wasm',
+  qrEncoder: QREncoder = DEFAULT_QR_ENCODER,
 ): QRTransferProfile {
   const normalizedVersion = normalizeQRVersion(version);
   const normalizedEccLevel = normalizeEccLevel(eccLevel);
-  const maxPacketSize = qrEncoder === 'js-qrcode'
-    ? getMaxByteCapacity(normalizedVersion, normalizedEccLevel)
-    : getMaxZXingWriterByteCapacity(normalizedVersion, normalizedEccLevel);
+  const maxPacketSize = qrEncoder === 'zxing-wasm'
+    ? getMaxZXingWriterByteCapacity(normalizedVersion, normalizedEccLevel)
+    : getMaxByteCapacity(normalizedVersion, normalizedEccLevel);
   const maxPayloadSize = maxPacketSize - HEADER_SIZE - CRC32C_SIZE;
   return {
     id: profileId(normalizedVersion, normalizedEccLevel),
diff --git a/src/core/qr/decode_settings.ts b/src/core/qr/decode_settings.ts
index a6643c0..6b5808d 100644
--- a/src/core/qr/decode_settings.ts
+++ b/src/core/qr/decode_settings.ts
@@ -1,7 +1,7 @@
 import type { Binarizer } from 'zxing-wasm/reader';
 
 export type DecodePresetId = 'fast' | 'balance' | 'robust' | 'custom';
-export type MaxSymbolsMode = 'auto' | 1 | 2 | 4;
+export type MaxSymbolsMode = 'auto' | 1 | 2 | 4 | 6 | 8;
 export type DownscaleFactor = 2 | 3 | 4;
 export type QrBinarizer = Binarizer;
 
@@ -48,7 +48,7 @@ export const BINARIZER_OPTIONS: QrBinarizer[] = [
   'BoolCast',
 ];
 
-export const MAX_SYMBOL_OPTIONS: MaxSymbolsMode[] = ['auto', 1, 2, 4];
+export const MAX_SYMBOL_OPTIONS: MaxSymbolsMode[] = ['auto', 1, 2, 4, 6, 8];
 export const DOWNSCALE_FACTOR_OPTIONS: DownscaleFactor[] = [2, 3, 4];
 
 export const DEFAULT_DECODE_PRESET: DecodePresetId = 'balance';
diff --git a/src/core/qr/qr_decode.ts b/src/core/qr/qr_decode.ts
index def8cb1..6c0d753 100644
--- a/src/core/qr/qr_decode.ts
+++ b/src/core/qr/qr_decode.ts
@@ -39,6 +39,7 @@ const READER_OPTIONS: ReaderOptions = {
 };
 
 const DEFAULT_MAX_QR_SYMBOLS = 4;
+const MAX_QR_SYMBOLS = 8;
 const SINGLE_QR_DECODE_OPTIONS: Required<QrDecodeOptions> = {
   ...DEFAULT_DECODE_SETTINGS,
   ...DECODE_PRESETS.robust,
@@ -170,7 +171,7 @@ function parseQRVersion(version: string, extra: string): number {
 
 function clampMaxSymbols(value: number): number {
   if (!Number.isFinite(value)) return DEFAULT_MAX_QR_SYMBOLS;
-  return Math.min(DEFAULT_MAX_QR_SYMBOLS, Math.max(1, Math.round(value)));
+  return Math.min(MAX_QR_SYMBOLS, Math.max(1, Math.round(value)));
 }
 
 function normalizeDecodeOptions(options: number | QrDecodeOptions): Required<QrDecodeOptions> {
diff --git a/src/core/sender/parallel_striping.ts b/src/core/sender/parallel_striping.ts
index 9384d68..08a91db 100644
--- a/src/core/sender/parallel_striping.ts
+++ b/src/core/sender/parallel_striping.ts
@@ -1,4 +1,4 @@
-export type ParallelQRCount = 1 | 2 | 4;
+export type ParallelQRCount = 1 | 2 | 4 | 6 | 8;
 
 export function stripedFrameCount(packetCount: number, parallelCount: ParallelQRCount): number {
   if (!Number.isInteger(packetCount) || packetCount < 0) {
diff --git a/src/tests/test_qr_modules.test.ts b/src/tests/test_qr_modules.test.ts
index 1d85b23..b15eebb 100644
--- a/src/tests/test_qr_modules.test.ts
+++ b/src/tests/test_qr_modules.test.ts
@@ -29,15 +29,19 @@ describe('QR encode', () => {
     expect(getMaxByteCapacity(40, 'M')).toBeGreaterThan(2000);
   });
 
-  it('should account for ZXing writer binary ECI overhead in transfer profiles', async () => {
+  it('should only apply ZXing writer binary ECI overhead to ZXing transfer profiles', async () => {
     const { createQRTransferProfile, getQRTransferProfile } = await import('@/core/protocol/profiles');
 
     expect(getMaxByteCapacity(20, 'L')).toBe(858);
     expect(getMaxZXingWriterByteCapacity(20, 'L')).toBe(856);
-    expect(getQRTransferProfile('v20-l').maxPacketSize).toBe(856);
-    expect(getQRTransferProfile('v20-l').maxPayloadSize).toBe(844);
+    expect(getQRTransferProfile('v20-l').maxPacketSize).toBe(858);
+    expect(getQRTransferProfile('v20-l').maxPayloadSize).toBe(846);
     expect(createQRTransferProfile(20, 'L', 'js-qrcode').maxPacketSize).toBe(858);
     expect(createQRTransferProfile(20, 'L', 'js-qrcode').maxPayloadSize).toBe(846);
+    expect(createQRTransferProfile(20, 'L', 'fast-qr-wasm').maxPacketSize).toBe(858);
+    expect(createQRTransferProfile(20, 'L', 'fast-qr-wasm').maxPayloadSize).toBe(846);
+    expect(createQRTransferProfile(20, 'L', 'zxing-wasm').maxPacketSize).toBe(856);
+    expect(createQRTransferProfile(20, 'L', 'zxing-wasm').maxPayloadSize).toBe(844);
   });
 
   it('should expose low-ECC transfer profiles with more payload room', async () => {
@@ -196,9 +200,9 @@ describe('Frame raster', () => {
   });
 
   it('should write and read a full V20-L transfer packet with ZXing WASM', async () => {
-    const { getQRTransferProfile } = await import('@/core/protocol/profiles');
+    const { createQRTransferProfile } = await import('@/core/protocol/profiles');
 
-    const profile = getQRTransferProfile('v20-l');
+    const profile = createQRTransferProfile(20, 'L', 'zxing-wasm');
     const packet = new Uint8Array(profile.maxPacketSize);
     for (let i = 0; i < packet.length; i++) packet[i] = i & 0xff;
 
@@ -258,4 +262,42 @@ describe('Parallel striping', () => {
     expect(seen).toEqual([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
     expect(emptyTiles).toBe(2);
   });
+
+  it('should support 8-way striping without duplicating packets', async () => {
+    const { stripedFrameCount, stripedPacketIndex } = await import('@/core/sender/parallel_striping');
+
+    const packetCount = 17;
+    const parallelCount = 8;
+    const frameCount = stripedFrameCount(packetCount, parallelCount);
+    const seen: number[] = [];
+    let emptyTiles = 0;
+
+    for (let frameIndex = 0; frameIndex < frameCount; frameIndex++) {
+      for (let tileIndex = 0; tileIndex < parallelCount; tileIndex++) {
+        const packetIndex = stripedPacketIndex(packetCount, parallelCount, frameIndex, tileIndex);
+        if (packetIndex === null) {
+          emptyTiles++;
+        } else {
+          seen.push(packetIndex);
+        }
+      }
+    }
+
+    expect(frameCount).toBe(3);
+    expect(seen).toEqual(Array.from({ length: packetCount }, (_, index) => index));
+    expect(emptyTiles).toBe(7);
+  });
+});
+
+describe('Transfer defaults', () => {
+  it('should default RaptorQ repair to 10 percent and expose manual 6/8 decode symbols', async () => {
+    const { DEFAULT_RAPTORQ_REPAIR_PERCENT, normalizeFecCodec } = await import('@/core/fec/codec');
+    const { MAX_SYMBOL_OPTIONS, normalizeDecodeSettings } = await import('@/core/qr/decode_settings');
+
+    expect(DEFAULT_RAPTORQ_REPAIR_PERCENT).toBe(10);
+    expect(normalizeFecCodec('js-rlnc')).toBe('js-rlnc');
+    expect(normalizeFecCodec('wasm-raptorq')).toBe('wasm-raptorq');
+    expect(MAX_SYMBOL_OPTIONS).toEqual(['auto', 1, 2, 4, 6, 8]);
+    expect(normalizeDecodeSettings({ maxSymbols: 8 }).maxSymbols).toBe(8);
+  });
 });
diff --git a/src/workers/gif.worker.ts b/src/workers/gif.worker.ts
index 52882a3..1b1f709 100644
--- a/src/workers/gif.worker.ts
+++ b/src/workers/gif.worker.ts
@@ -136,13 +136,15 @@ function normalizeEccLevel(value: EccLevel | undefined): EccLevel {
 }
 
 function normalizeParallelQRCount(value: number | undefined): ParallelQRCount {
-  return value === 2 || value === 4 ? value : 1;
+  return value === 1 || value === 2 || value === 4 || value === 6 || value === 8 ? value : 4;
 }
 
 function getParallelLayout(parallelCount: ParallelQRCount): { columns: number; rows: number } {
   if (parallelCount === 1) return { columns: 1, rows: 1 };
   if (parallelCount === 2) return { columns: 2, rows: 1 };
-  return { columns: 2, rows: 2 };
+  if (parallelCount === 4) return { columns: 2, rows: 2 };
+  if (parallelCount === 6) return { columns: 3, rows: 2 };
+  return { columns: 4, rows: 2 };
 }
 
 function blitImageData(