diff --git a/dist/decoder/decodeData/index.d.ts b/dist/decoder/decodeData/index.d.ts
index 732b0f9b..2cb2879f 100644
--- a/dist/decoder/decodeData/index.d.ts
+++ b/dist/decoder/decodeData/index.d.ts
@@ -10,7 +10,13 @@ export interface ECIChunk {
     type: Mode.ECI;
     assignmentNumber: number;
 }
-export declare type Chunks = Array<Chunk | ByteChunk | ECIChunk>;
+export interface StructuredAppend {
+    type: Mode.StructuredAppend;
+    currentSequence: number;
+    totalSequence: number;
+    parity: number;
+}
+export declare type Chunks = Array<Chunk | ByteChunk | ECIChunk | StructuredAppend>;
 export interface DecodedQR {
     text: string;
     bytes: number[];
@@ -22,5 +28,6 @@ export declare enum Mode {
     Byte = "byte",
     Kanji = "kanji",
     ECI = "eci",
+    StructuredAppend = "structuredappend"
 }
 export declare function decode(data: Uint8ClampedArray, version: number): DecodedQR;
diff --git a/dist/jsQR.js b/dist/jsQR.js
index 429afeac..869b9f8b 100644
--- a/dist/jsQR.js
+++ b/dist/jsQR.js
@@ -228,6 +228,7 @@ var GenericGFPoly = /** @class */ (function () {
         return this.coefficients[this.coefficients.length - 1 - degree];
     };
     GenericGFPoly.prototype.addOrSubtract = function (other) {
+        var _a;
         if (this.isZero()) {
             return other;
         }
@@ -248,7 +249,6 @@ var GenericGFPoly = /** @class */ (function () {
             sumDiff[i] = GenericGF_1.addOrSubtractGF(smallerCoefficients[i - lengthDiff], largerCoefficients[i]);
         }
         return new GenericGFPoly(this.field, sumDiff);
-        var _a;
     };
     GenericGFPoly.prototype.multiply = function (scalar) {
         if (scalar === 0) {
@@ -580,7 +580,7 @@ function readCodewords(matrix, version, formatInfo) {
     // Read columns in pairs, from right to left
     var readingUp = true;
     for (var columnIndex = dimension - 1; columnIndex > 0; columnIndex -= 2) {
-        if (columnIndex === 6) {
+        if (columnIndex === 6) { // Skip whole column with vertical alignment pattern;
             columnIndex--;
         }
         for (var i = 0; i < dimension; i++) {
@@ -594,7 +594,7 @@ function readCodewords(matrix, version, formatInfo) {
                         bit = !bit;
                     }
                     currentByte = pushBit(bit, currentByte);
-                    if (bitsRead === 8) {
+                    if (bitsRead === 8) { // Whole bytes
                         codewords.push(currentByte);
                         bitsRead = 0;
                         currentByte = 0;
@@ -609,7 +609,7 @@ function readCodewords(matrix, version, formatInfo) {
 function readVersion(matrix) {
     var dimension = matrix.height;
     var provisionalVersion = Math.floor((dimension - 17) / 4);
-    if (provisionalVersion <= 6) {
+    if (provisionalVersion <= 6) { // 6 and under dont have version info in the QR code
         return version_1.VERSIONS[provisionalVersion - 1];
     }
     var topRightVersionBits = 0;
@@ -651,21 +651,21 @@ function readVersion(matrix) {
 function readFormatInformation(matrix) {
     var topLeftFormatInfoBits = 0;
     for (var x = 0; x <= 8; x++) {
-        if (x !== 6) {
+        if (x !== 6) { // Skip timing pattern bit
             topLeftFormatInfoBits = pushBit(matrix.get(x, 8), topLeftFormatInfoBits);
         }
     }
     for (var y = 7; y >= 0; y--) {
-        if (y !== 6) {
+        if (y !== 6) { // Skip timing pattern bit
             topLeftFormatInfoBits = pushBit(matrix.get(8, y), topLeftFormatInfoBits);
         }
     }
     var dimension = matrix.height;
     var topRightBottomRightFormatInfoBits = 0;
-    for (var y = dimension - 1; y >= dimension - 7; y--) {
+    for (var y = dimension - 1; y >= dimension - 7; y--) { // bottom left
         topRightBottomRightFormatInfoBits = pushBit(matrix.get(8, y), topRightBottomRightFormatInfoBits);
     }
-    for (var x = dimension - 8; x < dimension; x++) {
+    for (var x = dimension - 8; x < dimension; x++) { // top right
         topRightBottomRightFormatInfoBits = pushBit(matrix.get(x, 8), topRightBottomRightFormatInfoBits);
     }
     var bestDifference = Infinity;
@@ -680,7 +680,7 @@ function readFormatInformation(matrix) {
             bestFormatInfo = formatInfo;
             bestDifference = difference;
         }
-        if (topLeftFormatInfoBits !== topRightBottomRightFormatInfoBits) {
+        if (topLeftFormatInfoBits !== topRightBottomRightFormatInfoBits) { // also try the other option
             difference = numBitsDiffering(topRightBottomRightFormatInfoBits, bits);
             if (difference < bestDifference) {
                 bestFormatInfo = formatInfo;
@@ -810,6 +810,7 @@ var Mode;
     Mode["Byte"] = "byte";
     Mode["Kanji"] = "kanji";
     Mode["ECI"] = "eci";
+    Mode["StructuredAppend"] = "structuredappend";
 })(Mode = exports.Mode || (exports.Mode = {}));
 var ModeByte;
 (function (ModeByte) {
@@ -819,7 +820,7 @@ var ModeByte;
     ModeByte[ModeByte["Byte"] = 4] = "Byte";
     ModeByte[ModeByte["Kanji"] = 8] = "Kanji";
     ModeByte[ModeByte["ECI"] = 7] = "ECI";
-    // StructuredAppend = 0x3,
+    ModeByte[ModeByte["StructuredAppend"] = 3] = "StructuredAppend";
     // FNC1FirstPosition = 0x5,
     // FNC1SecondPosition = 0x9,
 })(ModeByte || (ModeByte = {}));
@@ -926,6 +927,7 @@ function decodeKanji(stream, size) {
     return { bytes: bytes, text: text };
 }
 function decode(data, version) {
+    var _a, _b, _c, _d;
     var stream = new BitStream_1.BitStream(data);
     // There are 3 'sizes' based on the version. 1-9 is small (0), 10-26 is medium (1) and 27-40 is large (2).
     var size = version <= 9 ? 0 : version <= 26 ? 1 : 2;
@@ -1004,8 +1006,15 @@ function decode(data, version) {
                 text: kanjiResult.text,
             });
         }
+        else if (mode === ModeByte.StructuredAppend) {
+            result.chunks.push({
+                type: Mode.StructuredAppend,
+                currentSequence: stream.readBits(4),
+                totalSequence: stream.readBits(4),
+                parity: stream.readBits(8),
+            });
+        }
     }
-    var _a, _b, _c, _d;
 }
 exports.decode = decode;
 
@@ -8126,6 +8135,7 @@ Object.defineProperty(exports, "__esModule", { value: true });
 var GenericGF_1 = __webpack_require__(1);
 var GenericGFPoly_1 = __webpack_require__(2);
 function runEuclideanAlgorithm(field, a, b, R) {
+    var _a;
     // Assume a's degree is >= b's
     if (a.degree() < b.degree()) {
         _a = [b, a], a = _a[0], b = _a[1];
@@ -8166,7 +8176,6 @@ function runEuclideanAlgorithm(field, a, b, R) {
     }
     var inverse = field.inverse(sigmaTildeAtZero);
     return [t.multiply(inverse), r.multiply(inverse)];
-    var _a;
 }
 function findErrorLocations(field, errorLocator) {
     // This is a direct application of Chien's search
@@ -9571,7 +9580,7 @@ var BitMatrix_1 = __webpack_require__(0);
 function squareToQuadrilateral(p1, p2, p3, p4) {
     var dx3 = p1.x - p2.x + p3.x - p4.x;
     var dy3 = p1.y - p2.y + p3.y - p4.y;
-    if (dx3 === 0 && dy3 === 0) {
+    if (dx3 === 0 && dy3 === 0) { // Affine
         return {
             a11: p2.x - p1.x,
             a12: p2.y - p1.y,
@@ -9677,6 +9686,7 @@ function sum(values) {
 }
 // Takes three finder patterns and organizes them into topLeft, topRight, etc
 function reorderFinderPatterns(pattern1, pattern2, pattern3) {
+    var _a, _b, _c, _d;
     // Find distances between pattern centers
     var oneTwoDistance = distance(pattern1, pattern2);
     var twoThreeDistance = distance(pattern2, pattern3);
@@ -9701,7 +9711,6 @@ function reorderFinderPatterns(pattern1, pattern2, pattern3) {
         _d = [topRight, bottomLeft], bottomLeft = _d[0], topRight = _d[1];
     }
     return { bottomLeft: bottomLeft, topLeft: topLeft, topRight: topRight };
-    var _a, _b, _c, _d;
 }
 // Computes the dimension (number of modules on a side) of the QR Code based on the position of the finder patterns
 function computeDimension(topLeft, topRight, bottomLeft, matrix) {
@@ -9791,13 +9800,13 @@ function countBlackWhiteRunTowardsPoint(origin, end, matrix, length) {
 // along the line that intersects with the end point. Returns an array of elements, representing the pixel sizes
 // of the black white run. Takes a length which represents the number of switches from black to white to look for.
 function countBlackWhiteRun(origin, end, matrix, length) {
+    var _a;
     var rise = end.y - origin.y;
     var run = end.x - origin.x;
     var towardsEnd = countBlackWhiteRunTowardsPoint(origin, end, matrix, Math.ceil(length / 2));
     var awayFromEnd = countBlackWhiteRunTowardsPoint(origin, { x: origin.x - run, y: origin.y - rise }, matrix, Math.ceil(length / 2));
     var middleValue = towardsEnd.shift() + awayFromEnd.shift() - 1; // Substract one so we don't double count a pixel
     return (_a = awayFromEnd.concat(middleValue)).concat.apply(_a, towardsEnd);
-    var _a;
 }
 // Takes in a black white run and an array of expected ratios. Returns the average size of the run as well as the "error" -
 // that is the amount the run diverges from the expected ratio
@@ -9846,6 +9855,7 @@ function scorePattern(point, ratios, matrix) {
     }
 }
 function locate(matrix) {
+    var _a;
     var finderPatternQuads = [];
     var activeFinderPatternQuads = [];
     var alignmentPatternQuads = [];
@@ -9947,6 +9957,7 @@ function locate(matrix) {
     })
         .filter(function (q) { return !!q; }) // Filter out any rejected quads from above
         .sort(function (a, b) { return a.score - b.score; })
+        // Now take the top finder pattern options and try to find 2 other options with a similar size.
         .map(function (point, i, finderPatterns) {
         if (i > MAX_FINDERPATTERNS_TO_SEARCH) {
             return null;
@@ -9966,13 +9977,13 @@ function locate(matrix) {
     if (finderPatternGroups.length === 0) {
         return null;
     }
-    var _a = reorderFinderPatterns(finderPatternGroups[0].points[0], finderPatternGroups[0].points[1], finderPatternGroups[0].points[2]), topRight = _a.topRight, topLeft = _a.topLeft, bottomLeft = _a.bottomLeft;
+    var _b = reorderFinderPatterns(finderPatternGroups[0].points[0], finderPatternGroups[0].points[1], finderPatternGroups[0].points[2]), topRight = _b.topRight, topLeft = _b.topLeft, bottomLeft = _b.bottomLeft;
     // Now that we've found the three finder patterns we can determine the blockSize and the size of the QR code.
     // We'll use these to help find the alignment pattern but also later when we do the extraction.
     var dimension;
     var moduleSize;
     try {
-        (_b = computeDimension(topLeft, topRight, bottomLeft, matrix), dimension = _b.dimension, moduleSize = _b.moduleSize);
+        (_a = computeDimension(topLeft, topRight, bottomLeft, matrix), dimension = _a.dimension, moduleSize = _a.moduleSize);
     }
     catch (e) {
         return null;
@@ -10013,7 +10024,6 @@ function locate(matrix) {
         topLeft: { x: topLeft.x, y: topLeft.y },
         topRight: { x: topRight.x, y: topRight.y },
     };
-    var _b;
 }
 exports.locate = locate;
 
diff --git a/docs/jsQR.js b/docs/jsQR.js
index 429afeac..869b9f8b 100644
--- a/docs/jsQR.js
+++ b/docs/jsQR.js
@@ -228,6 +228,7 @@ var GenericGFPoly = /** @class */ (function () {
         return this.coefficients[this.coefficients.length - 1 - degree];
     };
     GenericGFPoly.prototype.addOrSubtract = function (other) {
+        var _a;
         if (this.isZero()) {
             return other;
         }
@@ -248,7 +249,6 @@ var GenericGFPoly = /** @class */ (function () {
             sumDiff[i] = GenericGF_1.addOrSubtractGF(smallerCoefficients[i - lengthDiff], largerCoefficients[i]);
         }
         return new GenericGFPoly(this.field, sumDiff);
-        var _a;
     };
     GenericGFPoly.prototype.multiply = function (scalar) {
         if (scalar === 0) {
@@ -580,7 +580,7 @@ function readCodewords(matrix, version, formatInfo) {
     // Read columns in pairs, from right to left
     var readingUp = true;
     for (var columnIndex = dimension - 1; columnIndex > 0; columnIndex -= 2) {
-        if (columnIndex === 6) {
+        if (columnIndex === 6) { // Skip whole column with vertical alignment pattern;
             columnIndex--;
         }
         for (var i = 0; i < dimension; i++) {
@@ -594,7 +594,7 @@ function readCodewords(matrix, version, formatInfo) {
                         bit = !bit;
                     }
                     currentByte = pushBit(bit, currentByte);
-                    if (bitsRead === 8) {
+                    if (bitsRead === 8) { // Whole bytes
                         codewords.push(currentByte);
                         bitsRead = 0;
                         currentByte = 0;
@@ -609,7 +609,7 @@ function readCodewords(matrix, version, formatInfo) {
 function readVersion(matrix) {
     var dimension = matrix.height;
     var provisionalVersion = Math.floor((dimension - 17) / 4);
-    if (provisionalVersion <= 6) {
+    if (provisionalVersion <= 6) { // 6 and under dont have version info in the QR code
         return version_1.VERSIONS[provisionalVersion - 1];
     }
     var topRightVersionBits = 0;
@@ -651,21 +651,21 @@ function readVersion(matrix) {
 function readFormatInformation(matrix) {
     var topLeftFormatInfoBits = 0;
     for (var x = 0; x <= 8; x++) {
-        if (x !== 6) {
+        if (x !== 6) { // Skip timing pattern bit
             topLeftFormatInfoBits = pushBit(matrix.get(x, 8), topLeftFormatInfoBits);
         }
     }
     for (var y = 7; y >= 0; y--) {
-        if (y !== 6) {
+        if (y !== 6) { // Skip timing pattern bit
             topLeftFormatInfoBits = pushBit(matrix.get(8, y), topLeftFormatInfoBits);
         }
     }
     var dimension = matrix.height;
     var topRightBottomRightFormatInfoBits = 0;
-    for (var y = dimension - 1; y >= dimension - 7; y--) {
+    for (var y = dimension - 1; y >= dimension - 7; y--) { // bottom left
         topRightBottomRightFormatInfoBits = pushBit(matrix.get(8, y), topRightBottomRightFormatInfoBits);
     }
-    for (var x = dimension - 8; x < dimension; x++) {
+    for (var x = dimension - 8; x < dimension; x++) { // top right
         topRightBottomRightFormatInfoBits = pushBit(matrix.get(x, 8), topRightBottomRightFormatInfoBits);
     }
     var bestDifference = Infinity;
@@ -680,7 +680,7 @@ function readFormatInformation(matrix) {
             bestFormatInfo = formatInfo;
             bestDifference = difference;
         }
-        if (topLeftFormatInfoBits !== topRightBottomRightFormatInfoBits) {
+        if (topLeftFormatInfoBits !== topRightBottomRightFormatInfoBits) { // also try the other option
             difference = numBitsDiffering(topRightBottomRightFormatInfoBits, bits);
             if (difference < bestDifference) {
                 bestFormatInfo = formatInfo;
@@ -810,6 +810,7 @@ var Mode;
     Mode["Byte"] = "byte";
     Mode["Kanji"] = "kanji";
     Mode["ECI"] = "eci";
+    Mode["StructuredAppend"] = "structuredappend";
 })(Mode = exports.Mode || (exports.Mode = {}));
 var ModeByte;
 (function (ModeByte) {
@@ -819,7 +820,7 @@ var ModeByte;
     ModeByte[ModeByte["Byte"] = 4] = "Byte";
     ModeByte[ModeByte["Kanji"] = 8] = "Kanji";
     ModeByte[ModeByte["ECI"] = 7] = "ECI";
-    // StructuredAppend = 0x3,
+    ModeByte[ModeByte["StructuredAppend"] = 3] = "StructuredAppend";
     // FNC1FirstPosition = 0x5,
     // FNC1SecondPosition = 0x9,
 })(ModeByte || (ModeByte = {}));
@@ -926,6 +927,7 @@ function decodeKanji(stream, size) {
     return { bytes: bytes, text: text };
 }
 function decode(data, version) {
+    var _a, _b, _c, _d;
     var stream = new BitStream_1.BitStream(data);
     // There are 3 'sizes' based on the version. 1-9 is small (0), 10-26 is medium (1) and 27-40 is large (2).
     var size = version <= 9 ? 0 : version <= 26 ? 1 : 2;
@@ -1004,8 +1006,15 @@ function decode(data, version) {
                 text: kanjiResult.text,
             });
         }
+        else if (mode === ModeByte.StructuredAppend) {
+            result.chunks.push({
+                type: Mode.StructuredAppend,
+                currentSequence: stream.readBits(4),
+                totalSequence: stream.readBits(4),
+                parity: stream.readBits(8),
+            });
+        }
     }
-    var _a, _b, _c, _d;
 }
 exports.decode = decode;
 
@@ -8126,6 +8135,7 @@ Object.defineProperty(exports, "__esModule", { value: true });
 var GenericGF_1 = __webpack_require__(1);
 var GenericGFPoly_1 = __webpack_require__(2);
 function runEuclideanAlgorithm(field, a, b, R) {
+    var _a;
     // Assume a's degree is >= b's
     if (a.degree() < b.degree()) {
         _a = [b, a], a = _a[0], b = _a[1];
@@ -8166,7 +8176,6 @@ function runEuclideanAlgorithm(field, a, b, R) {
     }
     var inverse = field.inverse(sigmaTildeAtZero);
     return [t.multiply(inverse), r.multiply(inverse)];
-    var _a;
 }
 function findErrorLocations(field, errorLocator) {
     // This is a direct application of Chien's search
@@ -9571,7 +9580,7 @@ var BitMatrix_1 = __webpack_require__(0);
 function squareToQuadrilateral(p1, p2, p3, p4) {
     var dx3 = p1.x - p2.x + p3.x - p4.x;
     var dy3 = p1.y - p2.y + p3.y - p4.y;
-    if (dx3 === 0 && dy3 === 0) {
+    if (dx3 === 0 && dy3 === 0) { // Affine
         return {
             a11: p2.x - p1.x,
             a12: p2.y - p1.y,
@@ -9677,6 +9686,7 @@ function sum(values) {
 }
 // Takes three finder patterns and organizes them into topLeft, topRight, etc
 function reorderFinderPatterns(pattern1, pattern2, pattern3) {
+    var _a, _b, _c, _d;
     // Find distances between pattern centers
     var oneTwoDistance = distance(pattern1, pattern2);
     var twoThreeDistance = distance(pattern2, pattern3);
@@ -9701,7 +9711,6 @@ function reorderFinderPatterns(pattern1, pattern2, pattern3) {
         _d = [topRight, bottomLeft], bottomLeft = _d[0], topRight = _d[1];
     }
     return { bottomLeft: bottomLeft, topLeft: topLeft, topRight: topRight };
-    var _a, _b, _c, _d;
 }
 // Computes the dimension (number of modules on a side) of the QR Code based on the position of the finder patterns
 function computeDimension(topLeft, topRight, bottomLeft, matrix) {
@@ -9791,13 +9800,13 @@ function countBlackWhiteRunTowardsPoint(origin, end, matrix, length) {
 // along the line that intersects with the end point. Returns an array of elements, representing the pixel sizes
 // of the black white run. Takes a length which represents the number of switches from black to white to look for.
 function countBlackWhiteRun(origin, end, matrix, length) {
+    var _a;
     var rise = end.y - origin.y;
     var run = end.x - origin.x;
     var towardsEnd = countBlackWhiteRunTowardsPoint(origin, end, matrix, Math.ceil(length / 2));
     var awayFromEnd = countBlackWhiteRunTowardsPoint(origin, { x: origin.x - run, y: origin.y - rise }, matrix, Math.ceil(length / 2));
     var middleValue = towardsEnd.shift() + awayFromEnd.shift() - 1; // Substract one so we don't double count a pixel
     return (_a = awayFromEnd.concat(middleValue)).concat.apply(_a, towardsEnd);
-    var _a;
 }
 // Takes in a black white run and an array of expected ratios. Returns the average size of the run as well as the "error" -
 // that is the amount the run diverges from the expected ratio
@@ -9846,6 +9855,7 @@ function scorePattern(point, ratios, matrix) {
     }
 }
 function locate(matrix) {
+    var _a;
     var finderPatternQuads = [];
     var activeFinderPatternQuads = [];
     var alignmentPatternQuads = [];
@@ -9947,6 +9957,7 @@ function locate(matrix) {
     })
         .filter(function (q) { return !!q; }) // Filter out any rejected quads from above
         .sort(function (a, b) { return a.score - b.score; })
+        // Now take the top finder pattern options and try to find 2 other options with a similar size.
         .map(function (point, i, finderPatterns) {
         if (i > MAX_FINDERPATTERNS_TO_SEARCH) {
             return null;
@@ -9966,13 +9977,13 @@ function locate(matrix) {
     if (finderPatternGroups.length === 0) {
         return null;
     }
-    var _a = reorderFinderPatterns(finderPatternGroups[0].points[0], finderPatternGroups[0].points[1], finderPatternGroups[0].points[2]), topRight = _a.topRight, topLeft = _a.topLeft, bottomLeft = _a.bottomLeft;
+    var _b = reorderFinderPatterns(finderPatternGroups[0].points[0], finderPatternGroups[0].points[1], finderPatternGroups[0].points[2]), topRight = _b.topRight, topLeft = _b.topLeft, bottomLeft = _b.bottomLeft;
     // Now that we've found the three finder patterns we can determine the blockSize and the size of the QR code.
     // We'll use these to help find the alignment pattern but also later when we do the extraction.
     var dimension;
     var moduleSize;
     try {
-        (_b = computeDimension(topLeft, topRight, bottomLeft, matrix), dimension = _b.dimension, moduleSize = _b.moduleSize);
+        (_a = computeDimension(topLeft, topRight, bottomLeft, matrix), dimension = _a.dimension, moduleSize = _a.moduleSize);
     }
     catch (e) {
         return null;
@@ -10013,7 +10024,6 @@ function locate(matrix) {
         topLeft: { x: topLeft.x, y: topLeft.y },
         topRight: { x: topRight.x, y: topRight.y },
     };
-    var _b;
 }
 exports.locate = locate;
 
diff --git a/src/decoder/decodeData/index.ts b/src/decoder/decodeData/index.ts
index f84163f2..49d2f2a3 100644
--- a/src/decoder/decodeData/index.ts
+++ b/src/decoder/decodeData/index.ts
@@ -17,7 +17,14 @@ export interface ECIChunk {
   assignmentNumber: number;
 }
 
-export type Chunks = Array<Chunk | ByteChunk | ECIChunk>;
+export interface StructuredAppend {
+  type: Mode.StructuredAppend;
+  currentSequence: number;
+  totalSequence: number;
+  parity: number;
+}
+
+export type Chunks = Array<Chunk | ByteChunk | ECIChunk | StructuredAppend>;
 
 export interface DecodedQR {
   text: string;
@@ -31,6 +38,7 @@ export enum Mode {
   Byte = "byte",
   Kanji = "kanji",
   ECI = "eci",
+  StructuredAppend = "structuredappend",
 }
 
 enum ModeByte {
@@ -40,7 +48,7 @@ enum ModeByte {
   Byte = 0x4,
   Kanji = 0x8,
   ECI = 0x7,
-  // StructuredAppend = 0x3,
+  StructuredAppend = 0x3,
   // FNC1FirstPosition = 0x5,
   // FNC1SecondPosition = 0x9,
 }
@@ -241,6 +249,13 @@ export function decode(data: Uint8ClampedArray, version: number): DecodedQR {
         bytes: kanjiResult.bytes,
         text: kanjiResult.text,
       });
+    } else if (mode === ModeByte.StructuredAppend) {
+      result.chunks.push({
+        type: Mode.StructuredAppend,
+        currentSequence: stream.readBits(4),
+        totalSequence: stream.readBits(4),
+        parity: stream.readBits(8),
+      });
     }
   }
 }
diff --git a/src/decoder/test-data/structuredAppend.png b/src/decoder/test-data/structuredAppend.png
new file mode 100644
index 00000000..f47f0557
Binary files /dev/null and b/src/decoder/test-data/structuredAppend.png differ
diff --git a/src/decoder/test.ts b/src/decoder/test.ts
index dd3c4f96..3ab21fdd 100644
--- a/src/decoder/test.ts
+++ b/src/decoder/test.ts
@@ -100,4 +100,24 @@ describe("decode", () => {
       ],
     });
   });
+  it("Supports StructuredAppend chunks", async () => {
+    const data = await loadBinarized("./src/decoder/test-data/structuredAppend.png");
+    console.log(data);
+    expect(decode(data)).toEqual({
+      text: "Hello ",
+      bytes: [72, 101, 108, 108, 111, 32],
+      chunks: [
+        {
+          currentSequence: 0, 
+          parity: 32, 
+          totalSequence: 1, 
+          type: "structuredappend"
+        }, {
+          type: "byte",
+          bytes: [72, 101, 108, 108, 111, 32],
+          text: "Hello ",
+        },
+      ],
+    });
+  });
 });