jimu-decompiled/sources/com/google/zxing/common/reedsolomon/ReedSolomonDecoder.java
2025-05-13 19:24:51 +02:00

119 lines
4.4 KiB
Java

package com.google.zxing.common.reedsolomon;
/* loaded from: classes.dex */
public final class ReedSolomonDecoder {
private final GenericGF a;
public ReedSolomonDecoder(GenericGF genericGF) {
this.a = genericGF;
}
public void a(int[] iArr, int i) throws ReedSolomonException {
GenericGFPoly genericGFPoly = new GenericGFPoly(this.a, iArr);
int[] iArr2 = new int[i];
boolean z = true;
for (int i2 = 0; i2 < i; i2++) {
GenericGF genericGF = this.a;
int a = genericGFPoly.a(genericGF.a(genericGF.a() + i2));
iArr2[(i - 1) - i2] = a;
if (a != 0) {
z = false;
}
}
if (z) {
return;
}
GenericGFPoly[] a2 = a(this.a.a(i, 1), new GenericGFPoly(this.a, iArr2), i);
GenericGFPoly genericGFPoly2 = a2[0];
GenericGFPoly genericGFPoly3 = a2[1];
int[] a3 = a(genericGFPoly2);
int[] a4 = a(genericGFPoly3, a3);
for (int i3 = 0; i3 < a3.length; i3++) {
int length = (iArr.length - 1) - this.a.c(a3[i3]);
if (length < 0) {
throw new ReedSolomonException("Bad error location");
}
iArr[length] = GenericGF.c(iArr[length], a4[i3]);
}
}
private GenericGFPoly[] a(GenericGFPoly genericGFPoly, GenericGFPoly genericGFPoly2, int i) throws ReedSolomonException {
if (genericGFPoly.b() < genericGFPoly2.b()) {
genericGFPoly2 = genericGFPoly;
genericGFPoly = genericGFPoly2;
}
GenericGFPoly d = this.a.d();
GenericGFPoly b = this.a.b();
do {
GenericGFPoly genericGFPoly3 = genericGFPoly2;
genericGFPoly2 = genericGFPoly;
genericGFPoly = genericGFPoly3;
GenericGFPoly genericGFPoly4 = b;
GenericGFPoly genericGFPoly5 = d;
d = genericGFPoly4;
if (genericGFPoly.b() >= i / 2) {
if (!genericGFPoly.c()) {
GenericGFPoly d2 = this.a.d();
int b2 = this.a.b(genericGFPoly.b(genericGFPoly.b()));
while (genericGFPoly2.b() >= genericGFPoly.b() && !genericGFPoly2.c()) {
int b3 = genericGFPoly2.b() - genericGFPoly.b();
int b4 = this.a.b(genericGFPoly2.b(genericGFPoly2.b()), b2);
d2 = d2.a(this.a.a(b3, b4));
genericGFPoly2 = genericGFPoly2.a(genericGFPoly.a(b3, b4));
}
b = d2.c(d).a(genericGFPoly5);
} else {
throw new ReedSolomonException("r_{i-1} was zero");
}
} else {
int b5 = d.b(0);
if (b5 != 0) {
int b6 = this.a.b(b5);
return new GenericGFPoly[]{d.c(b6), genericGFPoly.c(b6)};
}
throw new ReedSolomonException("sigmaTilde(0) was zero");
}
} while (genericGFPoly2.b() < genericGFPoly.b());
throw new IllegalStateException("Division algorithm failed to reduce polynomial?");
}
private int[] a(GenericGFPoly genericGFPoly) throws ReedSolomonException {
int b = genericGFPoly.b();
int i = 0;
if (b == 1) {
return new int[]{genericGFPoly.b(1)};
}
int[] iArr = new int[b];
for (int i2 = 1; i2 < this.a.c() && i < b; i2++) {
if (genericGFPoly.a(i2) == 0) {
iArr[i] = this.a.b(i2);
i++;
}
}
if (i == b) {
return iArr;
}
throw new ReedSolomonException("Error locator degree does not match number of roots");
}
private int[] a(GenericGFPoly genericGFPoly, int[] iArr) {
int length = iArr.length;
int[] iArr2 = new int[length];
for (int i = 0; i < length; i++) {
int b = this.a.b(iArr[i]);
int i2 = 1;
for (int i3 = 0; i3 < length; i3++) {
if (i != i3) {
int b2 = this.a.b(iArr[i3], b);
i2 = this.a.b(i2, (b2 & 1) == 0 ? b2 | 1 : b2 & (-2));
}
}
iArr2[i] = this.a.b(genericGFPoly.a(b), this.a.b(i2));
if (this.a.a() != 0) {
iArr2[i] = this.a.b(iArr2[i], b);
}
}
return iArr2;
}
}