diff options
Diffstat (limited to 'vendor/github.com/boombuler/barcode/utils/reedsolomon.go')
| -rw-r--r-- | vendor/github.com/boombuler/barcode/utils/reedsolomon.go | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/vendor/github.com/boombuler/barcode/utils/reedsolomon.go b/vendor/github.com/boombuler/barcode/utils/reedsolomon.go new file mode 100644 index 000000000..53af91ad4 --- /dev/null +++ b/vendor/github.com/boombuler/barcode/utils/reedsolomon.go @@ -0,0 +1,44 @@ +package utils + +import ( + "sync" +) + +type ReedSolomonEncoder struct { + gf *GaloisField + polynomes []*GFPoly + m *sync.Mutex +} + +func NewReedSolomonEncoder(gf *GaloisField) *ReedSolomonEncoder { + return &ReedSolomonEncoder{ + gf, []*GFPoly{NewGFPoly(gf, []int{1})}, new(sync.Mutex), + } +} + +func (rs *ReedSolomonEncoder) getPolynomial(degree int) *GFPoly { + rs.m.Lock() + defer rs.m.Unlock() + + if degree >= len(rs.polynomes) { + last := rs.polynomes[len(rs.polynomes)-1] + for d := len(rs.polynomes); d <= degree; d++ { + next := last.Multiply(NewGFPoly(rs.gf, []int{1, rs.gf.ALogTbl[d-1+rs.gf.Base]})) + rs.polynomes = append(rs.polynomes, next) + last = next + } + } + return rs.polynomes[degree] +} + +func (rs *ReedSolomonEncoder) Encode(data []int, eccCount int) []int { + generator := rs.getPolynomial(eccCount) + info := NewGFPoly(rs.gf, data) + info = info.MultByMonominal(eccCount, 1) + _, remainder := info.Divide(generator) + + result := make([]int, eccCount) + numZero := int(eccCount) - len(remainder.Coefficients) + copy(result[numZero:], remainder.Coefficients) + return result +} |
