vendor: add depends
chai2010
parent
643ab53ae7
commit
7f6d1f1371
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@ -0,0 +1,28 @@
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// Copyright 2015 <chaishushan{AT}gmail.com>. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// +build ingore
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package main
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import (
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"fmt"
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"io/ioutil"
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"log"
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qr "github.com/chai2010/image/qrencoder"
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)
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func main() {
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c, err := qr.Encode("hello, world", qr.L)
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if err != nil {
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log.Fatal(err)
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}
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err = ioutil.WriteFile("zz_qrout.png", c.PNG(), 0666)
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if err != nil {
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log.Fatal(err)
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}
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fmt.Print("output: zz_qrout.png\n")
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}
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149
vendor/github.com/chai2010/image/qrencoder/internal/coding/gen.go
generated
vendored
Normal file
149
vendor/github.com/chai2010/image/qrencoder/internal/coding/gen.go
generated
vendored
Normal file
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@ -0,0 +1,149 @@
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// +build ignore
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package main
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import "fmt"
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// tables from qrencode-3.1.1/qrspec.c
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var capacity = [41]struct {
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width int
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words int
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remainder int
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ec [4]int
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}{
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{0, 0, 0, [4]int{0, 0, 0, 0}},
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{21, 26, 0, [4]int{7, 10, 13, 17}}, // 1
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{25, 44, 7, [4]int{10, 16, 22, 28}},
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{29, 70, 7, [4]int{15, 26, 36, 44}},
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{33, 100, 7, [4]int{20, 36, 52, 64}},
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{37, 134, 7, [4]int{26, 48, 72, 88}}, // 5
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{41, 172, 7, [4]int{36, 64, 96, 112}},
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{45, 196, 0, [4]int{40, 72, 108, 130}},
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{49, 242, 0, [4]int{48, 88, 132, 156}},
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{53, 292, 0, [4]int{60, 110, 160, 192}},
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{57, 346, 0, [4]int{72, 130, 192, 224}}, //10
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{61, 404, 0, [4]int{80, 150, 224, 264}},
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{65, 466, 0, [4]int{96, 176, 260, 308}},
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{69, 532, 0, [4]int{104, 198, 288, 352}},
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{73, 581, 3, [4]int{120, 216, 320, 384}},
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{77, 655, 3, [4]int{132, 240, 360, 432}}, //15
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{81, 733, 3, [4]int{144, 280, 408, 480}},
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{85, 815, 3, [4]int{168, 308, 448, 532}},
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{89, 901, 3, [4]int{180, 338, 504, 588}},
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{93, 991, 3, [4]int{196, 364, 546, 650}},
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{97, 1085, 3, [4]int{224, 416, 600, 700}}, //20
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{101, 1156, 4, [4]int{224, 442, 644, 750}},
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{105, 1258, 4, [4]int{252, 476, 690, 816}},
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{109, 1364, 4, [4]int{270, 504, 750, 900}},
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{113, 1474, 4, [4]int{300, 560, 810, 960}},
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{117, 1588, 4, [4]int{312, 588, 870, 1050}}, //25
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{121, 1706, 4, [4]int{336, 644, 952, 1110}},
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{125, 1828, 4, [4]int{360, 700, 1020, 1200}},
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{129, 1921, 3, [4]int{390, 728, 1050, 1260}},
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{133, 2051, 3, [4]int{420, 784, 1140, 1350}},
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{137, 2185, 3, [4]int{450, 812, 1200, 1440}}, //30
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{141, 2323, 3, [4]int{480, 868, 1290, 1530}},
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{145, 2465, 3, [4]int{510, 924, 1350, 1620}},
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{149, 2611, 3, [4]int{540, 980, 1440, 1710}},
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{153, 2761, 3, [4]int{570, 1036, 1530, 1800}},
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{157, 2876, 0, [4]int{570, 1064, 1590, 1890}}, //35
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{161, 3034, 0, [4]int{600, 1120, 1680, 1980}},
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{165, 3196, 0, [4]int{630, 1204, 1770, 2100}},
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{169, 3362, 0, [4]int{660, 1260, 1860, 2220}},
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{173, 3532, 0, [4]int{720, 1316, 1950, 2310}},
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{177, 3706, 0, [4]int{750, 1372, 2040, 2430}}, //40
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}
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var eccTable = [41][4][2]int{
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{{0, 0}, {0, 0}, {0, 0}, {0, 0}},
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{{1, 0}, {1, 0}, {1, 0}, {1, 0}}, // 1
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{{1, 0}, {1, 0}, {1, 0}, {1, 0}},
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{{1, 0}, {1, 0}, {2, 0}, {2, 0}},
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{{1, 0}, {2, 0}, {2, 0}, {4, 0}},
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{{1, 0}, {2, 0}, {2, 2}, {2, 2}}, // 5
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{{2, 0}, {4, 0}, {4, 0}, {4, 0}},
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{{2, 0}, {4, 0}, {2, 4}, {4, 1}},
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{{2, 0}, {2, 2}, {4, 2}, {4, 2}},
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{{2, 0}, {3, 2}, {4, 4}, {4, 4}},
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{{2, 2}, {4, 1}, {6, 2}, {6, 2}}, //10
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{{4, 0}, {1, 4}, {4, 4}, {3, 8}},
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{{2, 2}, {6, 2}, {4, 6}, {7, 4}},
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{{4, 0}, {8, 1}, {8, 4}, {12, 4}},
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{{3, 1}, {4, 5}, {11, 5}, {11, 5}},
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{{5, 1}, {5, 5}, {5, 7}, {11, 7}}, //15
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{{5, 1}, {7, 3}, {15, 2}, {3, 13}},
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{{1, 5}, {10, 1}, {1, 15}, {2, 17}},
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{{5, 1}, {9, 4}, {17, 1}, {2, 19}},
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{{3, 4}, {3, 11}, {17, 4}, {9, 16}},
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{{3, 5}, {3, 13}, {15, 5}, {15, 10}}, //20
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{{4, 4}, {17, 0}, {17, 6}, {19, 6}},
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{{2, 7}, {17, 0}, {7, 16}, {34, 0}},
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{{4, 5}, {4, 14}, {11, 14}, {16, 14}},
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{{6, 4}, {6, 14}, {11, 16}, {30, 2}},
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{{8, 4}, {8, 13}, {7, 22}, {22, 13}}, //25
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{{10, 2}, {19, 4}, {28, 6}, {33, 4}},
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{{8, 4}, {22, 3}, {8, 26}, {12, 28}},
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{{3, 10}, {3, 23}, {4, 31}, {11, 31}},
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{{7, 7}, {21, 7}, {1, 37}, {19, 26}},
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{{5, 10}, {19, 10}, {15, 25}, {23, 25}}, //30
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{{13, 3}, {2, 29}, {42, 1}, {23, 28}},
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{{17, 0}, {10, 23}, {10, 35}, {19, 35}},
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{{17, 1}, {14, 21}, {29, 19}, {11, 46}},
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{{13, 6}, {14, 23}, {44, 7}, {59, 1}},
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{{12, 7}, {12, 26}, {39, 14}, {22, 41}}, //35
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{{6, 14}, {6, 34}, {46, 10}, {2, 64}},
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{{17, 4}, {29, 14}, {49, 10}, {24, 46}},
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{{4, 18}, {13, 32}, {48, 14}, {42, 32}},
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{{20, 4}, {40, 7}, {43, 22}, {10, 67}},
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{{19, 6}, {18, 31}, {34, 34}, {20, 61}}, //40
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}
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var align = [41][2]int{
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{0, 0},
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{0, 0}, {18, 0}, {22, 0}, {26, 0}, {30, 0}, // 1- 5
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{34, 0}, {22, 38}, {24, 42}, {26, 46}, {28, 50}, // 6-10
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{30, 54}, {32, 58}, {34, 62}, {26, 46}, {26, 48}, //11-15
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{26, 50}, {30, 54}, {30, 56}, {30, 58}, {34, 62}, //16-20
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{28, 50}, {26, 50}, {30, 54}, {28, 54}, {32, 58}, //21-25
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{30, 58}, {34, 62}, {26, 50}, {30, 54}, {26, 52}, //26-30
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{30, 56}, {34, 60}, {30, 58}, {34, 62}, {30, 54}, //31-35
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{24, 50}, {28, 54}, {32, 58}, {26, 54}, {30, 58}, //35-40
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}
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var versionPattern = [41]int{
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0,
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0, 0, 0, 0, 0, 0,
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0x07c94, 0x085bc, 0x09a99, 0x0a4d3, 0x0bbf6, 0x0c762, 0x0d847, 0x0e60d,
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0x0f928, 0x10b78, 0x1145d, 0x12a17, 0x13532, 0x149a6, 0x15683, 0x168c9,
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0x177ec, 0x18ec4, 0x191e1, 0x1afab, 0x1b08e, 0x1cc1a, 0x1d33f, 0x1ed75,
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0x1f250, 0x209d5, 0x216f0, 0x228ba, 0x2379f, 0x24b0b, 0x2542e, 0x26a64,
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0x27541, 0x28c69,
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}
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func main() {
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fmt.Printf("\t{},\n")
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for i := 1; i <= 40; i++ {
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apos := align[i][0] - 2
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if apos < 0 {
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apos = 100
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}
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astride := align[i][1] - align[i][0]
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if astride < 1 {
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astride = 100
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}
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fmt.Printf("\t{%v, %v, %v, %#x, [4]level{{%v, %v}, {%v, %v}, {%v, %v}, {%v, %v}}}, // %v\n",
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apos, astride, capacity[i].words,
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versionPattern[i],
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eccTable[i][0][0]+eccTable[i][0][1],
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float64(capacity[i].ec[0])/float64(eccTable[i][0][0]+eccTable[i][0][1]),
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eccTable[i][1][0]+eccTable[i][1][1],
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float64(capacity[i].ec[1])/float64(eccTable[i][1][0]+eccTable[i][1][1]),
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eccTable[i][2][0]+eccTable[i][2][1],
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float64(capacity[i].ec[2])/float64(eccTable[i][2][0]+eccTable[i][2][1]),
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eccTable[i][3][0]+eccTable[i][3][1],
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float64(capacity[i].ec[3])/float64(eccTable[i][3][0]+eccTable[i][3][1]),
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i,
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)
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}
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}
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@ -0,0 +1,815 @@
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// Copyright 2011 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package coding implements low-level QR coding details.
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package coding
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import (
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"fmt"
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"strconv"
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"strings"
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"github.com/chai2010/image/qrencoder/internal/gf256"
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)
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// Field is the field for QR error correction.
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var Field = gf256.NewField(0x11d, 2)
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// A Version represents a QR version.
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// The version specifies the size of the QR code:
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// a QR code with version v has 4v+17 pixels on a side.
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// Versions number from 1 to 40: the larger the version,
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// the more information the code can store.
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type Version int
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const MinVersion = 1
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const MaxVersion = 40
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func (v Version) String() string {
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return strconv.Itoa(int(v))
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}
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func (v Version) sizeClass() int {
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if v <= 9 {
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return 0
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}
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if v <= 26 {
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return 1
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}
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return 2
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}
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// DataBytes returns the number of data bytes that can be
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// stored in a QR code with the given version and level.
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func (v Version) DataBytes(l Level) int {
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vt := &vtab[v]
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lev := &vt.level[l]
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return vt.bytes - lev.nblock*lev.check
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}
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// Encoding implements a QR data encoding scheme.
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// The implementations--Numeric, Alphanumeric, and String--specify
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// the character set and the mapping from UTF-8 to code bits.
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// The more restrictive the mode, the fewer code bits are needed.
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type Encoding interface {
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Check() error
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Bits(v Version) int
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Encode(b *Bits, v Version)
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}
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type Bits struct {
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b []byte
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nbit int
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}
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func (b *Bits) Reset() {
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b.b = b.b[:0]
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b.nbit = 0
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}
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func (b *Bits) Bits() int {
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return b.nbit
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}
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func (b *Bits) Bytes() []byte {
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if b.nbit%8 != 0 {
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panic("fractional byte")
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}
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return b.b
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}
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func (b *Bits) Append(p []byte) {
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if b.nbit%8 != 0 {
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panic("fractional byte")
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}
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b.b = append(b.b, p...)
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b.nbit += 8 * len(p)
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}
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func (b *Bits) Write(v uint, nbit int) {
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for nbit > 0 {
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n := nbit
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if n > 8 {
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n = 8
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}
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if b.nbit%8 == 0 {
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b.b = append(b.b, 0)
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} else {
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m := -b.nbit & 7
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if n > m {
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n = m
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}
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}
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b.nbit += n
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sh := uint(nbit - n)
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b.b[len(b.b)-1] |= uint8(v >> sh << uint(-b.nbit&7))
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v -= v >> sh << sh
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nbit -= n
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}
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}
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// Num is the encoding for numeric data.
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// The only valid characters are the decimal digits 0 through 9.
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type Num string
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func (s Num) String() string {
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return fmt.Sprintf("Num(%#q)", string(s))
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}
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func (s Num) Check() error {
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for _, c := range s {
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if c < '0' || '9' < c {
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return fmt.Errorf("non-numeric string %#q", string(s))
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}
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}
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return nil
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}
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var numLen = [3]int{10, 12, 14}
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func (s Num) Bits(v Version) int {
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return 4 + numLen[v.sizeClass()] + (10*len(s)+2)/3
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}
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func (s Num) Encode(b *Bits, v Version) {
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b.Write(1, 4)
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b.Write(uint(len(s)), numLen[v.sizeClass()])
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var i int
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for i = 0; i+3 <= len(s); i += 3 {
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w := uint(s[i]-'0')*100 + uint(s[i+1]-'0')*10 + uint(s[i+2]-'0')
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b.Write(w, 10)
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}
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switch len(s) - i {
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case 1:
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w := uint(s[i] - '0')
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b.Write(w, 4)
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case 2:
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w := uint(s[i]-'0')*10 + uint(s[i+1]-'0')
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b.Write(w, 7)
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}
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}
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// Alpha is the encoding for alphanumeric data.
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// The valid characters are 0-9A-Z$%*+-./: and space.
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type Alpha string
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const alphabet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:"
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func (s Alpha) String() string {
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return fmt.Sprintf("Alpha(%#q)", string(s))
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}
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func (s Alpha) Check() error {
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for _, c := range s {
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if strings.IndexRune(alphabet, c) < 0 {
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return fmt.Errorf("non-alphanumeric string %#q", string(s))
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}
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}
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return nil
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}
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var alphaLen = [3]int{9, 11, 13}
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func (s Alpha) Bits(v Version) int {
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return 4 + alphaLen[v.sizeClass()] + (11*len(s)+1)/2
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}
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func (s Alpha) Encode(b *Bits, v Version) {
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b.Write(2, 4)
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b.Write(uint(len(s)), alphaLen[v.sizeClass()])
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var i int
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for i = 0; i+2 <= len(s); i += 2 {
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w := uint(strings.IndexRune(alphabet, rune(s[i])))*45 +
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uint(strings.IndexRune(alphabet, rune(s[i+1])))
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b.Write(w, 11)
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}
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if i < len(s) {
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w := uint(strings.IndexRune(alphabet, rune(s[i])))
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b.Write(w, 6)
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}
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}
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// String is the encoding for 8-bit data. All bytes are valid.
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type String string
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func (s String) String() string {
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return fmt.Sprintf("String(%#q)", string(s))
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}
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func (s String) Check() error {
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return nil
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}
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var stringLen = [3]int{8, 16, 16}
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func (s String) Bits(v Version) int {
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return 4 + stringLen[v.sizeClass()] + 8*len(s)
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}
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func (s String) Encode(b *Bits, v Version) {
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b.Write(4, 4)
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b.Write(uint(len(s)), stringLen[v.sizeClass()])
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for i := 0; i < len(s); i++ {
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b.Write(uint(s[i]), 8)
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}
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}
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// A Pixel describes a single pixel in a QR code.
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type Pixel uint32
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const (
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Black Pixel = 1 << iota
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Invert
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)
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func (p Pixel) Offset() uint {
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return uint(p >> 6)
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}
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func OffsetPixel(o uint) Pixel {
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return Pixel(o << 6)
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}
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|
||||
func (r PixelRole) Pixel() Pixel {
|
||||
return Pixel(r << 2)
|
||||
}
|
||||
|
||||
func (p Pixel) Role() PixelRole {
|
||||
return PixelRole(p>>2) & 15
|
||||
}
|
||||
|
||||
func (p Pixel) String() string {
|
||||
s := p.Role().String()
|
||||
if p&Black != 0 {
|
||||
s += "+black"
|
||||
}
|
||||
if p&Invert != 0 {
|
||||
s += "+invert"
|
||||
}
|
||||
s += "+" + strconv.FormatUint(uint64(p.Offset()), 10)
|
||||
return s
|
||||
}
|
||||
|
||||
// A PixelRole describes the role of a QR pixel.
|
||||
type PixelRole uint32
|
||||
|
||||
const (
|
||||
_ PixelRole = iota
|
||||
Position // position squares (large)
|
||||
Alignment // alignment squares (small)
|
||||
Timing // timing strip between position squares
|
||||
Format // format metadata
|
||||
PVersion // version pattern
|
||||
Unused // unused pixel
|
||||
Data // data bit
|
||||
Check // error correction check bit
|
||||
Extra
|
||||
)
|
||||
|
||||
var roles = []string{
|
||||
"",
|
||||
"position",
|
||||
"alignment",
|
||||
"timing",
|
||||
"format",
|
||||
"pversion",
|
||||
"unused",
|
||||
"data",
|
||||
"check",
|
||||
"extra",
|
||||
}
|
||||
|
||||
func (r PixelRole) String() string {
|
||||
if Position <= r && r <= Check {
|
||||
return roles[r]
|
||||
}
|
||||
return strconv.Itoa(int(r))
|
||||
}
|
||||
|
||||
// A Level represents a QR error correction level.
|
||||
// From least to most tolerant of errors, they are L, M, Q, H.
|
||||
type Level int
|
||||
|
||||
const (
|
||||
L Level = iota
|
||||
M
|
||||
Q
|
||||
H
|
||||
)
|
||||
|
||||
func (l Level) String() string {
|
||||
if L <= l && l <= H {
|
||||
return "LMQH"[l : l+1]
|
||||
}
|
||||
return strconv.Itoa(int(l))
|
||||
}
|
||||
|
||||
// A Code is a square pixel grid.
|
||||
type Code struct {
|
||||
Bitmap []byte // 1 is black, 0 is white
|
||||
Size int // number of pixels on a side
|
||||
Stride int // number of bytes per row
|
||||
}
|
||||
|
||||
func (c *Code) Black(x, y int) bool {
|
||||
return 0 <= x && x < c.Size && 0 <= y && y < c.Size &&
|
||||
c.Bitmap[y*c.Stride+x/8]&(1<<uint(7-x&7)) != 0
|
||||
}
|
||||
|
||||
// A Mask describes a mask that is applied to the QR
|
||||
// code to avoid QR artifacts being interpreted as
|
||||
// alignment and timing patterns (such as the squares
|
||||
// in the corners). Valid masks are integers from 0 to 7.
|
||||
type Mask int
|
||||
|
||||
// http://www.swetake.com/qr/qr5_en.html
|
||||
var mfunc = []func(int, int) bool{
|
||||
func(i, j int) bool { return (i+j)%2 == 0 },
|
||||
func(i, j int) bool { return i%2 == 0 },
|
||||
func(i, j int) bool { return j%3 == 0 },
|
||||
func(i, j int) bool { return (i+j)%3 == 0 },
|
||||
func(i, j int) bool { return (i/2+j/3)%2 == 0 },
|
||||
func(i, j int) bool { return i*j%2+i*j%3 == 0 },
|
||||
func(i, j int) bool { return (i*j%2+i*j%3)%2 == 0 },
|
||||
func(i, j int) bool { return (i*j%3+(i+j)%2)%2 == 0 },
|
||||
}
|
||||
|
||||
func (m Mask) Invert(y, x int) bool {
|
||||
if m < 0 {
|
||||
return false
|
||||
}
|
||||
return mfunc[m](y, x)
|
||||
}
|
||||
|
||||
// A Plan describes how to construct a QR code
|
||||
// with a specific version, level, and mask.
|
||||
type Plan struct {
|
||||
Version Version
|
||||
Level Level
|
||||
Mask Mask
|
||||
|
||||
DataBytes int // number of data bytes
|
||||
CheckBytes int // number of error correcting (checksum) bytes
|
||||
Blocks int // number of data blocks
|
||||
|
||||
Pixel [][]Pixel // pixel map
|
||||
}
|
||||
|
||||
// NewPlan returns a Plan for a QR code with the given
|
||||
// version, level, and mask.
|
||||
func NewPlan(version Version, level Level, mask Mask) (*Plan, error) {
|
||||
p, err := vplan(version)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if err := fplan(level, mask, p); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if err := lplan(version, level, p); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if err := mplan(mask, p); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return p, nil
|
||||
}
|
||||
|
||||
func (b *Bits) Pad(n int) {
|
||||
if n < 0 {
|
||||
panic("qr: invalid pad size")
|
||||
}
|
||||
if n <= 4 {
|
||||
b.Write(0, n)
|
||||
} else {
|
||||
b.Write(0, 4)
|
||||
n -= 4
|
||||
n -= -b.Bits() & 7
|
||||
b.Write(0, -b.Bits()&7)
|
||||
pad := n / 8
|
||||
for i := 0; i < pad; i += 2 {
|
||||
b.Write(0xec, 8)
|
||||
if i+1 >= pad {
|
||||
break
|
||||
}
|
||||
b.Write(0x11, 8)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (b *Bits) AddCheckBytes(v Version, l Level) {
|
||||
nd := v.DataBytes(l)
|
||||
if b.nbit < nd*8 {
|
||||
b.Pad(nd*8 - b.nbit)
|
||||
}
|
||||
if b.nbit != nd*8 {
|
||||
panic("qr: too much data")
|
||||
}
|
||||
|
||||
dat := b.Bytes()
|
||||
vt := &vtab[v]
|
||||
lev := &vt.level[l]
|
||||
db := nd / lev.nblock
|
||||
extra := nd % lev.nblock
|
||||
chk := make([]byte, lev.check)
|
||||
rs := gf256.NewRSEncoder(Field, lev.check)
|
||||
for i := 0; i < lev.nblock; i++ {
|
||||
if i == lev.nblock-extra {
|
||||
db++
|
||||
}
|
||||
rs.ECC(dat[:db], chk)
|
||||
b.Append(chk)
|
||||
dat = dat[db:]
|
||||
}
|
||||
|
||||
if len(b.Bytes()) != vt.bytes {
|
||||
panic("qr: internal error")
|
||||
}
|
||||
}
|
||||
|
||||
func (p *Plan) Encode(text ...Encoding) (*Code, error) {
|
||||
var b Bits
|
||||
for _, t := range text {
|
||||
if err := t.Check(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
t.Encode(&b, p.Version)
|
||||
}
|
||||
if b.Bits() > p.DataBytes*8 {
|
||||
return nil, fmt.Errorf("cannot encode %d bits into %d-bit code", b.Bits(), p.DataBytes*8)
|
||||
}
|
||||
b.AddCheckBytes(p.Version, p.Level)
|
||||
bytes := b.Bytes()
|
||||
|
||||
// Now we have the checksum bytes and the data bytes.
|
||||
// Construct the actual code.
|
||||
c := &Code{Size: len(p.Pixel), Stride: (len(p.Pixel) + 7) &^ 7}
|
||||
c.Bitmap = make([]byte, c.Stride*c.Size)
|
||||
crow := c.Bitmap
|
||||
for _, row := range p.Pixel {
|
||||
for x, pix := range row {
|
||||
switch pix.Role() {
|
||||
case Data, Check:
|
||||
o := pix.Offset()
|
||||
if bytes[o/8]&(1<<uint(7-o&7)) != 0 {
|
||||
pix ^= Black
|
||||
}
|
||||
}
|
||||
if pix&Black != 0 {
|
||||
crow[x/8] |= 1 << uint(7-x&7)
|
||||
}
|
||||
}
|
||||
crow = crow[c.Stride:]
|
||||
}
|
||||
return c, nil
|
||||
}
|
||||
|
||||
// A version describes metadata associated with a version.
|
||||
type version struct {
|
||||
apos int
|
||||
astride int
|
||||
bytes int
|
||||
pattern int
|
||||
level [4]level
|
||||
}
|
||||
|
||||
type level struct {
|
||||
nblock int
|
||||
check int
|
||||
}
|
||||
|
||||
var vtab = []version{
|
||||
{},
|
||||
{100, 100, 26, 0x0, [4]level{{1, 7}, {1, 10}, {1, 13}, {1, 17}}}, // 1
|
||||
{16, 100, 44, 0x0, [4]level{{1, 10}, {1, 16}, {1, 22}, {1, 28}}}, // 2
|
||||
{20, 100, 70, 0x0, [4]level{{1, 15}, {1, 26}, {2, 18}, {2, 22}}}, // 3
|
||||
{24, 100, 100, 0x0, [4]level{{1, 20}, {2, 18}, {2, 26}, {4, 16}}}, // 4
|
||||
{28, 100, 134, 0x0, [4]level{{1, 26}, {2, 24}, {4, 18}, {4, 22}}}, // 5
|
||||
{32, 100, 172, 0x0, [4]level{{2, 18}, {4, 16}, {4, 24}, {4, 28}}}, // 6
|
||||
{20, 16, 196, 0x7c94, [4]level{{2, 20}, {4, 18}, {6, 18}, {5, 26}}}, // 7
|
||||
{22, 18, 242, 0x85bc, [4]level{{2, 24}, {4, 22}, {6, 22}, {6, 26}}}, // 8
|
||||
{24, 20, 292, 0x9a99, [4]level{{2, 30}, {5, 22}, {8, 20}, {8, 24}}}, // 9
|
||||
{26, 22, 346, 0xa4d3, [4]level{{4, 18}, {5, 26}, {8, 24}, {8, 28}}}, // 10
|
||||
{28, 24, 404, 0xbbf6, [4]level{{4, 20}, {5, 30}, {8, 28}, {11, 24}}}, // 11
|
||||
{30, 26, 466, 0xc762, [4]level{{4, 24}, {8, 22}, {10, 26}, {11, 28}}}, // 12
|
||||
{32, 28, 532, 0xd847, [4]level{{4, 26}, {9, 22}, {12, 24}, {16, 22}}}, // 13
|
||||
{24, 20, 581, 0xe60d, [4]level{{4, 30}, {9, 24}, {16, 20}, {16, 24}}}, // 14
|
||||
{24, 22, 655, 0xf928, [4]level{{6, 22}, {10, 24}, {12, 30}, {18, 24}}}, // 15
|
||||
{24, 24, 733, 0x10b78, [4]level{{6, 24}, {10, 28}, {17, 24}, {16, 30}}}, // 16
|
||||
{28, 24, 815, 0x1145d, [4]level{{6, 28}, {11, 28}, {16, 28}, {19, 28}}}, // 17
|
||||
{28, 26, 901, 0x12a17, [4]level{{6, 30}, {13, 26}, {18, 28}, {21, 28}}}, // 18
|
||||
{28, 28, 991, 0x13532, [4]level{{7, 28}, {14, 26}, {21, 26}, {25, 26}}}, // 19
|
||||
{32, 28, 1085, 0x149a6, [4]level{{8, 28}, {16, 26}, {20, 30}, {25, 28}}}, // 20
|
||||
{26, 22, 1156, 0x15683, [4]level{{8, 28}, {17, 26}, {23, 28}, {25, 30}}}, // 21
|
||||
{24, 24, 1258, 0x168c9, [4]level{{9, 28}, {17, 28}, {23, 30}, {34, 24}}}, // 22
|
||||
{28, 24, 1364, 0x177ec, [4]level{{9, 30}, {18, 28}, {25, 30}, {30, 30}}}, // 23
|
||||
{26, 26, 1474, 0x18ec4, [4]level{{10, 30}, {20, 28}, {27, 30}, {32, 30}}}, // 24
|
||||
{30, 26, 1588, 0x191e1, [4]level{{12, 26}, {21, 28}, {29, 30}, {35, 30}}}, // 25
|
||||
{28, 28, 1706, 0x1afab, [4]level{{12, 28}, {23, 28}, {34, 28}, {37, 30}}}, // 26
|
||||
{32, 28, 1828, 0x1b08e, [4]level{{12, 30}, {25, 28}, {34, 30}, {40, 30}}}, // 27
|
||||
{24, 24, 1921, 0x1cc1a, [4]level{{13, 30}, {26, 28}, {35, 30}, {42, 30}}}, // 28
|
||||
{28, 24, 2051, 0x1d33f, [4]level{{14, 30}, {28, 28}, {38, 30}, {45, 30}}}, // 29
|
||||
{24, 26, 2185, 0x1ed75, [4]level{{15, 30}, {29, 28}, {40, 30}, {48, 30}}}, // 30
|
||||
{28, 26, 2323, 0x1f250, [4]level{{16, 30}, {31, 28}, {43, 30}, {51, 30}}}, // 31
|
||||
{32, 26, 2465, 0x209d5, [4]level{{17, 30}, {33, 28}, {45, 30}, {54, 30}}}, // 32
|
||||
{28, 28, 2611, 0x216f0, [4]level{{18, 30}, {35, 28}, {48, 30}, {57, 30}}}, // 33
|
||||
{32, 28, 2761, 0x228ba, [4]level{{19, 30}, {37, 28}, {51, 30}, {60, 30}}}, // 34
|
||||
{28, 24, 2876, 0x2379f, [4]level{{19, 30}, {38, 28}, {53, 30}, {63, 30}}}, // 35
|
||||
{22, 26, 3034, 0x24b0b, [4]level{{20, 30}, {40, 28}, {56, 30}, {66, 30}}}, // 36
|
||||
{26, 26, 3196, 0x2542e, [4]level{{21, 30}, {43, 28}, {59, 30}, {70, 30}}}, // 37
|
||||
{30, 26, 3362, 0x26a64, [4]level{{22, 30}, {45, 28}, {62, 30}, {74, 30}}}, // 38
|
||||
{24, 28, 3532, 0x27541, [4]level{{24, 30}, {47, 28}, {65, 30}, {77, 30}}}, // 39
|
||||
{28, 28, 3706, 0x28c69, [4]level{{25, 30}, {49, 28}, {68, 30}, {81, 30}}}, // 40
|
||||
}
|
||||
|
||||
func grid(siz int) [][]Pixel {
|
||||
m := make([][]Pixel, siz)
|
||||
pix := make([]Pixel, siz*siz)
|
||||
for i := range m {
|
||||
m[i], pix = pix[:siz], pix[siz:]
|
||||
}
|
||||
return m
|
||||
}
|
||||
|
||||
// vplan creates a Plan for the given version.
|
||||
func vplan(v Version) (*Plan, error) {
|
||||
p := &Plan{Version: v}
|
||||
if v < 1 || v > 40 {
|
||||
return nil, fmt.Errorf("invalid QR version %d", int(v))
|
||||
}
|
||||
siz := 17 + int(v)*4
|
||||
m := grid(siz)
|
||||
p.Pixel = m
|
||||
|
||||
// Timing markers (overwritten by boxes).
|
||||
const ti = 6 // timing is in row/column 6 (counting from 0)
|
||||
for i := range m {
|
||||
p := Timing.Pixel()
|
||||
if i&1 == 0 {
|
||||
p |= Black
|
||||
}
|
||||
m[i][ti] = p
|
||||
m[ti][i] = p
|
||||
}
|
||||
|
||||
// Position boxes.
|
||||
posBox(m, 0, 0)
|
||||
posBox(m, siz-7, 0)
|
||||
posBox(m, 0, siz-7)
|
||||
|
||||
// Alignment boxes.
|
||||
info := &vtab[v]
|
||||
for x := 4; x+5 < siz; {
|
||||
for y := 4; y+5 < siz; {
|
||||
// don't overwrite timing markers
|
||||
if (x < 7 && y < 7) || (x < 7 && y+5 >= siz-7) || (x+5 >= siz-7 && y < 7) {
|
||||
} else {
|
||||
alignBox(m, x, y)
|
||||
}
|
||||
if y == 4 {
|
||||
y = info.apos
|
||||
} else {
|
||||
y += info.astride
|
||||
}
|
||||
}
|
||||
if x == 4 {
|
||||
x = info.apos
|
||||
} else {
|
||||
x += info.astride
|
||||
}
|
||||
}
|
||||
|
||||
// Version pattern.
|
||||
pat := vtab[v].pattern
|
||||
if pat != 0 {
|
||||
v := pat
|
||||
for x := 0; x < 6; x++ {
|
||||
for y := 0; y < 3; y++ {
|
||||
p := PVersion.Pixel()
|
||||
if v&1 != 0 {
|
||||
p |= Black
|
||||
}
|
||||
m[siz-11+y][x] = p
|
||||
m[x][siz-11+y] = p
|
||||
v >>= 1
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// One lonely black pixel
|
||||
m[siz-8][8] = Unused.Pixel() | Black
|
||||
|
||||
return p, nil
|
||||
}
|
||||
|
||||
// fplan adds the format pixels
|
||||
func fplan(l Level, m Mask, p *Plan) error {
|
||||
// Format pixels.
|
||||
fb := uint32(l^1) << 13 // level: L=01, M=00, Q=11, H=10
|
||||
fb |= uint32(m) << 10 // mask
|
||||
const formatPoly = 0x537
|
||||
rem := fb
|
||||
for i := 14; i >= 10; i-- {
|
||||
if rem&(1<<uint(i)) != 0 {
|
||||
rem ^= formatPoly << uint(i-10)
|
||||
}
|
||||
}
|
||||
fb |= rem
|
||||
invert := uint32(0x5412)
|
||||
siz := len(p.Pixel)
|
||||
for i := uint(0); i < 15; i++ {
|
||||
pix := Format.Pixel() + OffsetPixel(i)
|
||||
if (fb>>i)&1 == 1 {
|
||||
pix |= Black
|
||||
}
|
||||
if (invert>>i)&1 == 1 {
|
||||
pix ^= Invert | Black
|
||||
}
|
||||
// top left
|
||||
switch {
|
||||
case i < 6:
|
||||
p.Pixel[i][8] = pix
|
||||
case i < 8:
|
||||
p.Pixel[i+1][8] = pix
|
||||
case i < 9:
|
||||
p.Pixel[8][7] = pix
|
||||
default:
|
||||
p.Pixel[8][14-i] = pix
|
||||
}
|
||||
// bottom right
|
||||
switch {
|
||||
case i < 8:
|
||||
p.Pixel[8][siz-1-int(i)] = pix
|
||||
default:
|
||||
p.Pixel[siz-1-int(14-i)][8] = pix
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// lplan edits a version-only Plan to add information
|
||||
// about the error correction levels.
|
||||
func lplan(v Version, l Level, p *Plan) error {
|
||||
p.Level = l
|
||||
|
||||
nblock := vtab[v].level[l].nblock
|
||||
ne := vtab[v].level[l].check
|
||||
nde := (vtab[v].bytes - ne*nblock) / nblock
|
||||
extra := (vtab[v].bytes - ne*nblock) % nblock
|
||||
dataBits := (nde*nblock + extra) * 8
|
||||
checkBits := ne * nblock * 8
|
||||
|
||||
p.DataBytes = vtab[v].bytes - ne*nblock
|
||||
p.CheckBytes = ne * nblock
|
||||
p.Blocks = nblock
|
||||
|
||||
// Make data + checksum pixels.
|
||||
data := make([]Pixel, dataBits)
|
||||
for i := range data {
|
||||
data[i] = Data.Pixel() | OffsetPixel(uint(i))
|
||||
}
|
||||
check := make([]Pixel, checkBits)
|
||||
for i := range check {
|
||||
check[i] = Check.Pixel() | OffsetPixel(uint(i+dataBits))
|
||||
}
|
||||
|
||||
// Split into blocks.
|
||||
dataList := make([][]Pixel, nblock)
|
||||
checkList := make([][]Pixel, nblock)
|
||||
for i := 0; i < nblock; i++ {
|
||||
// The last few blocks have an extra data byte (8 pixels).
|
||||
nd := nde
|
||||
if i >= nblock-extra {
|
||||
nd++
|
||||
}
|
||||
dataList[i], data = data[0:nd*8], data[nd*8:]
|
||||
checkList[i], check = check[0:ne*8], check[ne*8:]
|
||||
}
|
||||
if len(data) != 0 || len(check) != 0 {
|
||||
panic("data/check math")
|
||||
}
|
||||
|
||||
// Build up bit sequence, taking first byte of each block,
|
||||
// then second byte, and so on. Then checksums.
|
||||
bits := make([]Pixel, dataBits+checkBits)
|
||||
dst := bits
|
||||
for i := 0; i < nde+1; i++ {
|
||||
for _, b := range dataList {
|
||||
if i*8 < len(b) {
|
||||
copy(dst, b[i*8:(i+1)*8])
|
||||
dst = dst[8:]
|
||||
}
|
||||
}
|
||||
}
|
||||
for i := 0; i < ne; i++ {
|
||||
for _, b := range checkList {
|
||||
if i*8 < len(b) {
|
||||
copy(dst, b[i*8:(i+1)*8])
|
||||
dst = dst[8:]
|
||||
}
|
||||
}
|
||||
}
|
||||
if len(dst) != 0 {
|
||||
panic("dst math")
|
||||
}
|
||||
|
||||
// Sweep up pair of columns,
|
||||
// then down, assigning to right then left pixel.
|
||||
// Repeat.
|
||||
// See Figure 2 of http://www.pclviewer.com/rs2/qrtopology.htm
|
||||
siz := len(p.Pixel)
|
||||
rem := make([]Pixel, 7)
|
||||
for i := range rem {
|
||||
rem[i] = Extra.Pixel()
|
||||
}
|
||||
src := append(bits, rem...)
|
||||
for x := siz; x > 0; {
|
||||
for y := siz - 1; y >= 0; y-- {
|
||||
if p.Pixel[y][x-1].Role() == 0 {
|
||||
p.Pixel[y][x-1], src = src[0], src[1:]
|
||||
}
|
||||
if p.Pixel[y][x-2].Role() == 0 {
|
||||
p.Pixel[y][x-2], src = src[0], src[1:]
|
||||
}
|
||||
}
|
||||
x -= 2
|
||||
if x == 7 { // vertical timing strip
|
||||
x--
|
||||
}
|
||||
for y := 0; y < siz; y++ {
|
||||
if p.Pixel[y][x-1].Role() == 0 {
|
||||
p.Pixel[y][x-1], src = src[0], src[1:]
|
||||
}
|
||||
if p.Pixel[y][x-2].Role() == 0 {
|
||||
p.Pixel[y][x-2], src = src[0], src[1:]
|
||||
}
|
||||
}
|
||||
x -= 2
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// mplan edits a version+level-only Plan to add the mask.
|
||||
func mplan(m Mask, p *Plan) error {
|
||||
p.Mask = m
|
||||
for y, row := range p.Pixel {
|
||||
for x, pix := range row {
|
||||
if r := pix.Role(); (r == Data || r == Check || r == Extra) && p.Mask.Invert(y, x) {
|
||||
row[x] ^= Black | Invert
|
||||
}
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// posBox draws a position (large) box at upper left x, y.
|
||||
func posBox(m [][]Pixel, x, y int) {
|
||||
pos := Position.Pixel()
|
||||
// box
|
||||
for dy := 0; dy < 7; dy++ {
|
||||
for dx := 0; dx < 7; dx++ {
|
||||
p := pos
|
||||
if dx == 0 || dx == 6 || dy == 0 || dy == 6 || 2 <= dx && dx <= 4 && 2 <= dy && dy <= 4 {
|
||||
p |= Black
|
||||
}
|
||||
m[y+dy][x+dx] = p
|
||||
}
|
||||
}
|
||||
// white border
|
||||
for dy := -1; dy < 8; dy++ {
|
||||
if 0 <= y+dy && y+dy < len(m) {
|
||||
if x > 0 {
|
||||
m[y+dy][x-1] = pos
|
||||
}
|
||||
if x+7 < len(m) {
|
||||
m[y+dy][x+7] = pos
|
||||
}
|
||||
}
|
||||
}
|
||||
for dx := -1; dx < 8; dx++ {
|
||||
if 0 <= x+dx && x+dx < len(m) {
|
||||
if y > 0 {
|
||||
m[y-1][x+dx] = pos
|
||||
}
|
||||
if y+7 < len(m) {
|
||||
m[y+7][x+dx] = pos
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// alignBox draw an alignment (small) box at upper left x, y.
|
||||
func alignBox(m [][]Pixel, x, y int) {
|
||||
// box
|
||||
align := Alignment.Pixel()
|
||||
for dy := 0; dy < 5; dy++ {
|
||||
for dx := 0; dx < 5; dx++ {
|
||||
p := align
|
||||
if dx == 0 || dx == 4 || dy == 0 || dy == 4 || dx == 2 && dy == 2 {
|
||||
p |= Black
|
||||
}
|
||||
m[y+dy][x+dx] = p
|
||||
}
|
||||
}
|
||||
}
|
||||
85
vendor/github.com/chai2010/image/qrencoder/internal/gf256/blog_test.go
generated
vendored
Normal file
85
vendor/github.com/chai2010/image/qrencoder/internal/gf256/blog_test.go
generated
vendored
Normal file
|
|
@ -0,0 +1,85 @@
|
|||
// Copyright 2012 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// This file contains a straightforward implementation of
|
||||
// Reed-Solomon encoding, along with a benchmark.
|
||||
// It goes with http://research.swtch.com/field.
|
||||
//
|
||||
// For an optimized implementation, see gf256.go.
|
||||
|
||||
package gf256
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"fmt"
|
||||
"testing"
|
||||
)
|
||||
|
||||
// BlogECC writes to check the error correcting code bytes
|
||||
// for data using the given Reed-Solomon parameters.
|
||||
func BlogECC(rs *RSEncoder, m []byte, check []byte) {
|
||||
if len(check) < rs.c {
|
||||
panic("gf256: invalid check byte length")
|
||||
}
|
||||
if rs.c == 0 {
|
||||
return
|
||||
}
|
||||
|
||||
// The check bytes are the remainder after dividing
|
||||
// data padded with c zeros by the generator polynomial.
|
||||
|
||||
// p = data padded with c zeros.
|
||||
var p []byte
|
||||
n := len(m) + rs.c
|
||||
if len(rs.p) >= n {
|
||||
p = rs.p
|
||||
} else {
|
||||
p = make([]byte, n)
|
||||
}
|
||||
copy(p, m)
|
||||
for i := len(m); i < len(p); i++ {
|
||||
p[i] = 0
|
||||
}
|
||||
|
||||
gen := rs.gen
|
||||
|
||||
// Divide p by gen, leaving the remainder in p[len(data):].
|
||||
// p[0] is the most significant term in p, and
|
||||
// gen[0] is the most significant term in the generator.
|
||||
for i := 0; i < len(m); i++ {
|
||||
k := f.Mul(p[i], f.Inv(gen[0])) // k = pi / g0
|
||||
// p -= k·g
|
||||
for j, g := range gen {
|
||||
p[i+j] = f.Add(p[i+j], f.Mul(k, g))
|
||||
}
|
||||
}
|
||||
|
||||
copy(check, p[len(m):])
|
||||
rs.p = p
|
||||
}
|
||||
|
||||
func BenchmarkBlogECC(b *testing.B) {
|
||||
data := []byte{0x10, 0x20, 0x0c, 0x56, 0x61, 0x80, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0x10, 0x20, 0x0c, 0x56, 0x61, 0x80, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11}
|
||||
check := []byte{0x29, 0x41, 0xb3, 0x93, 0x8, 0xe8, 0xa3, 0xe7, 0x63, 0x8f}
|
||||
out := make([]byte, len(check))
|
||||
rs := NewRSEncoder(f, len(check))
|
||||
for i := 0; i < b.N; i++ {
|
||||
BlogECC(rs, data, out)
|
||||
}
|
||||
b.SetBytes(int64(len(data)))
|
||||
if !bytes.Equal(out, check) {
|
||||
fmt.Printf("have %#v want %#v\n", out, check)
|
||||
}
|
||||
}
|
||||
|
||||
func TestBlogECC(t *testing.T) {
|
||||
data := []byte{0x10, 0x20, 0x0c, 0x56, 0x61, 0x80, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11}
|
||||
check := []byte{0xa5, 0x24, 0xd4, 0xc1, 0xed, 0x36, 0xc7, 0x87, 0x2c, 0x55}
|
||||
out := make([]byte, len(check))
|
||||
rs := NewRSEncoder(f, len(check))
|
||||
BlogECC(rs, data, out)
|
||||
if !bytes.Equal(out, check) {
|
||||
t.Errorf("have %x want %x", out, check)
|
||||
}
|
||||
}
|
||||
241
vendor/github.com/chai2010/image/qrencoder/internal/gf256/gf256.go
generated
vendored
Normal file
241
vendor/github.com/chai2010/image/qrencoder/internal/gf256/gf256.go
generated
vendored
Normal file
|
|
@ -0,0 +1,241 @@
|
|||
// Copyright 2010 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// Package gf256 implements arithmetic over the Galois Field GF(256).
|
||||
package gf256
|
||||
|
||||
import "strconv"
|
||||
|
||||
// A Field represents an instance of GF(256) defined by a specific polynomial.
|
||||
type Field struct {
|
||||
log [256]byte // log[0] is unused
|
||||
exp [510]byte
|
||||
}
|
||||
|
||||
// NewField returns a new field corresponding to the polynomial poly
|
||||
// and generator α. The Reed-Solomon encoding in QR codes uses
|
||||
// polynomial 0x11d with generator 2.
|
||||
//
|
||||
// The choice of generator α only affects the Exp and Log operations.
|
||||
func NewField(poly, α int) *Field {
|
||||
if poly < 0x100 || poly >= 0x200 || reducible(poly) {
|
||||
panic("gf256: invalid polynomial: " + strconv.Itoa(poly))
|
||||
}
|
||||
|
||||
var f Field
|
||||
x := 1
|
||||
for i := 0; i < 255; i++ {
|
||||
if x == 1 && i != 0 {
|
||||
panic("gf256: invalid generator " + strconv.Itoa(α) +
|
||||
" for polynomial " + strconv.Itoa(poly))
|
||||
}
|
||||
f.exp[i] = byte(x)
|
||||
f.exp[i+255] = byte(x)
|
||||
f.log[x] = byte(i)
|
||||
x = mul(x, α, poly)
|
||||
}
|
||||
f.log[0] = 255
|
||||
for i := 0; i < 255; i++ {
|
||||
if f.log[f.exp[i]] != byte(i) {
|
||||
panic("bad log")
|
||||
}
|
||||
if f.log[f.exp[i+255]] != byte(i) {
|
||||
panic("bad log")
|
||||
}
|
||||
}
|
||||
for i := 1; i < 256; i++ {
|
||||
if f.exp[f.log[i]] != byte(i) {
|
||||
panic("bad log")
|
||||
}
|
||||
}
|
||||
|
||||
return &f
|
||||
}
|
||||
|
||||
// nbit returns the number of significant in p.
|
||||
func nbit(p int) uint {
|
||||
n := uint(0)
|
||||
for ; p > 0; p >>= 1 {
|
||||
n++
|
||||
}
|
||||
return n
|
||||
}
|
||||
|
||||
// polyDiv divides the polynomial p by q and returns the remainder.
|
||||
func polyDiv(p, q int) int {
|
||||
np := nbit(p)
|
||||
nq := nbit(q)
|
||||
for ; np >= nq; np-- {
|
||||
if p&(1<<(np-1)) != 0 {
|
||||
p ^= q << (np - nq)
|
||||
}
|
||||
}
|
||||
return p
|
||||
}
|
||||
|
||||
// mul returns the product x*y mod poly, a GF(256) multiplication.
|
||||
func mul(x, y, poly int) int {
|
||||
z := 0
|
||||
for x > 0 {
|
||||
if x&1 != 0 {
|
||||
z ^= y
|
||||
}
|
||||
x >>= 1
|
||||
y <<= 1
|
||||
if y&0x100 != 0 {
|
||||
y ^= poly
|
||||
}
|
||||
}
|
||||
return z
|
||||
}
|
||||
|
||||
// reducible reports whether p is reducible.
|
||||
func reducible(p int) bool {
|
||||
// Multiplying n-bit * n-bit produces (2n-1)-bit,
|
||||
// so if p is reducible, one of its factors must be
|
||||
// of np/2+1 bits or fewer.
|
||||
np := nbit(p)
|
||||
for q := 2; q < 1<<(np/2+1); q++ {
|
||||
if polyDiv(p, q) == 0 {
|
||||
return true
|
||||
}
|
||||
}
|
||||
return false
|
||||
}
|
||||
|
||||
// Add returns the sum of x and y in the field.
|
||||
func (f *Field) Add(x, y byte) byte {
|
||||
return x ^ y
|
||||
}
|
||||
|
||||
// Exp returns the base-α exponential of e in the field.
|
||||
// If e < 0, Exp returns 0.
|
||||
func (f *Field) Exp(e int) byte {
|
||||
if e < 0 {
|
||||
return 0
|
||||
}
|
||||
return f.exp[e%255]
|
||||
}
|
||||
|
||||
// Log returns the base-α logarithm of x in the field.
|
||||
// If x == 0, Log returns -1.
|
||||
func (f *Field) Log(x byte) int {
|
||||
if x == 0 {
|
||||
return -1
|
||||
}
|
||||
return int(f.log[x])
|
||||
}
|
||||
|
||||
// Inv returns the multiplicative inverse of x in the field.
|
||||
// If x == 0, Inv returns 0.
|
||||
func (f *Field) Inv(x byte) byte {
|
||||
if x == 0 {
|
||||
return 0
|
||||
}
|
||||
return f.exp[255-f.log[x]]
|
||||
}
|
||||
|
||||
// Mul returns the product of x and y in the field.
|
||||
func (f *Field) Mul(x, y byte) byte {
|
||||
if x == 0 || y == 0 {
|
||||
return 0
|
||||
}
|
||||
return f.exp[int(f.log[x])+int(f.log[y])]
|
||||
}
|
||||
|
||||
// An RSEncoder implements Reed-Solomon encoding
|
||||
// over a given field using a given number of error correction bytes.
|
||||
type RSEncoder struct {
|
||||
f *Field
|
||||
c int
|
||||
gen []byte
|
||||
lgen []byte
|
||||
p []byte
|
||||
}
|
||||
|
||||
func (f *Field) gen(e int) (gen, lgen []byte) {
|
||||
// p = 1
|
||||
p := make([]byte, e+1)
|
||||
p[e] = 1
|
||||
|
||||
for i := 0; i < e; i++ {
|
||||
// p *= (x + Exp(i))
|
||||
// p[j] = p[j]*Exp(i) + p[j+1].
|
||||
c := f.Exp(i)
|
||||
for j := 0; j < e; j++ {
|
||||
p[j] = f.Mul(p[j], c) ^ p[j+1]
|
||||
}
|
||||
p[e] = f.Mul(p[e], c)
|
||||
}
|
||||
|
||||
// lp = log p.
|
||||
lp := make([]byte, e+1)
|
||||
for i, c := range p {
|
||||
if c == 0 {
|
||||
lp[i] = 255
|
||||
} else {
|
||||
lp[i] = byte(f.Log(c))
|
||||
}
|
||||
}
|
||||
|
||||
return p, lp
|
||||
}
|
||||
|
||||
// NewRSEncoder returns a new Reed-Solomon encoder
|
||||
// over the given field and number of error correction bytes.
|
||||
func NewRSEncoder(f *Field, c int) *RSEncoder {
|
||||
gen, lgen := f.gen(c)
|
||||
return &RSEncoder{f: f, c: c, gen: gen, lgen: lgen}
|
||||
}
|
||||
|
||||
// ECC writes to check the error correcting code bytes
|
||||
// for data using the given Reed-Solomon parameters.
|
||||
func (rs *RSEncoder) ECC(data []byte, check []byte) {
|
||||
if len(check) < rs.c {
|
||||
panic("gf256: invalid check byte length")
|
||||
}
|
||||
if rs.c == 0 {
|
||||
return
|
||||
}
|
||||
|
||||
// The check bytes are the remainder after dividing
|
||||
// data padded with c zeros by the generator polynomial.
|
||||
|
||||
// p = data padded with c zeros.
|
||||
var p []byte
|
||||
n := len(data) + rs.c
|
||||
if len(rs.p) >= n {
|
||||
p = rs.p
|
||||
} else {
|
||||
p = make([]byte, n)
|
||||
}
|
||||
copy(p, data)
|
||||
for i := len(data); i < len(p); i++ {
|
||||
p[i] = 0
|
||||
}
|
||||
|
||||
// Divide p by gen, leaving the remainder in p[len(data):].
|
||||
// p[0] is the most significant term in p, and
|
||||
// gen[0] is the most significant term in the generator,
|
||||
// which is always 1.
|
||||
// To avoid repeated work, we store various values as
|
||||
// lv, not v, where lv = log[v].
|
||||
f := rs.f
|
||||
lgen := rs.lgen[1:]
|
||||
for i := 0; i < len(data); i++ {
|
||||
c := p[i]
|
||||
if c == 0 {
|
||||
continue
|
||||
}
|
||||
q := p[i+1:]
|
||||
exp := f.exp[f.log[c]:]
|
||||
for j, lg := range lgen {
|
||||
if lg != 255 { // lgen uses 255 for log 0
|
||||
q[j] ^= exp[lg]
|
||||
}
|
||||
}
|
||||
}
|
||||
copy(check, p[len(data):])
|
||||
rs.p = p
|
||||
}
|
||||
194
vendor/github.com/chai2010/image/qrencoder/internal/gf256/gf256_test.go
generated
vendored
Normal file
194
vendor/github.com/chai2010/image/qrencoder/internal/gf256/gf256_test.go
generated
vendored
Normal file
|
|
@ -0,0 +1,194 @@
|
|||
// Copyright 2010 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package gf256
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"fmt"
|
||||
"testing"
|
||||
)
|
||||
|
||||
var f = NewField(0x11d, 2) // x^8 + x^4 + x^3 + x^2 + 1
|
||||
|
||||
func TestBasic(t *testing.T) {
|
||||
if f.Exp(0) != 1 || f.Exp(1) != 2 || f.Exp(255) != 1 {
|
||||
panic("bad Exp")
|
||||
}
|
||||
}
|
||||
|
||||
func TestECC(t *testing.T) {
|
||||
data := []byte{0x10, 0x20, 0x0c, 0x56, 0x61, 0x80, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11}
|
||||
check := []byte{0xa5, 0x24, 0xd4, 0xc1, 0xed, 0x36, 0xc7, 0x87, 0x2c, 0x55}
|
||||
out := make([]byte, len(check))
|
||||
rs := NewRSEncoder(f, len(check))
|
||||
rs.ECC(data, out)
|
||||
if !bytes.Equal(out, check) {
|
||||
t.Errorf("have %x want %x", out, check)
|
||||
}
|
||||
}
|
||||
|
||||
func TestLinear(t *testing.T) {
|
||||
d1 := []byte{0x00, 0x00}
|
||||
c1 := []byte{0x00, 0x00}
|
||||
out := make([]byte, len(c1))
|
||||
rs := NewRSEncoder(f, len(c1))
|
||||
if rs.ECC(d1, out); !bytes.Equal(out, c1) {
|
||||
t.Errorf("ECBytes(%x, %d) = %x, want 0", d1, len(c1), out)
|
||||
}
|
||||
d2 := []byte{0x00, 0x01}
|
||||
c2 := make([]byte, 2)
|
||||
rs.ECC(d2, c2)
|
||||
d3 := []byte{0x00, 0x02}
|
||||
c3 := make([]byte, 2)
|
||||
rs.ECC(d3, c3)
|
||||
cx := make([]byte, 2)
|
||||
for i := range cx {
|
||||
cx[i] = c2[i] ^ c3[i]
|
||||
}
|
||||
d4 := []byte{0x00, 0x03}
|
||||
c4 := make([]byte, 2)
|
||||
rs.ECC(d4, c4)
|
||||
if !bytes.Equal(cx, c4) {
|
||||
t.Errorf("ECBytes(%x, 2) = %x\nECBytes(%x, 2) = %x\nxor = %x\nECBytes(%x, 2) = %x",
|
||||
d2, c2, d3, c3, cx, d4, c4)
|
||||
}
|
||||
}
|
||||
|
||||
func TestGaussJordan(t *testing.T) {
|
||||
rs := NewRSEncoder(f, 2)
|
||||
m := make([][]byte, 16)
|
||||
for i := range m {
|
||||
m[i] = make([]byte, 4)
|
||||
m[i][i/8] = 1 << uint(i%8)
|
||||
rs.ECC(m[i][:2], m[i][2:])
|
||||
}
|
||||
if false {
|
||||
fmt.Printf("---\n")
|
||||
for _, row := range m {
|
||||
fmt.Printf("%x\n", row)
|
||||
}
|
||||
}
|
||||
b := []uint{0, 1, 2, 3, 12, 13, 14, 15, 20, 21, 22, 23, 24, 25, 26, 27}
|
||||
for i := 0; i < 16; i++ {
|
||||
bi := b[i]
|
||||
if m[i][bi/8]&(1<<(7-bi%8)) == 0 {
|
||||
for j := i + 1; ; j++ {
|
||||
if j >= len(m) {
|
||||
t.Errorf("lost track for %d", bi)
|
||||
break
|
||||
}
|
||||
if m[j][bi/8]&(1<<(7-bi%8)) != 0 {
|
||||
m[i], m[j] = m[j], m[i]
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
for j := i + 1; j < len(m); j++ {
|
||||
if m[j][bi/8]&(1<<(7-bi%8)) != 0 {
|
||||
for k := range m[j] {
|
||||
m[j][k] ^= m[i][k]
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
if false {
|
||||
fmt.Printf("---\n")
|
||||
for _, row := range m {
|
||||
fmt.Printf("%x\n", row)
|
||||
}
|
||||
}
|
||||
for i := 15; i >= 0; i-- {
|
||||
bi := b[i]
|
||||
for j := i - 1; j >= 0; j-- {
|
||||
if m[j][bi/8]&(1<<(7-bi%8)) != 0 {
|
||||
for k := range m[j] {
|
||||
m[j][k] ^= m[i][k]
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
if false {
|
||||
fmt.Printf("---\n")
|
||||
for _, row := range m {
|
||||
fmt.Printf("%x", row)
|
||||
out := make([]byte, 2)
|
||||
if rs.ECC(row[:2], out); !bytes.Equal(out, row[2:]) {
|
||||
fmt.Printf(" - want %x", out)
|
||||
}
|
||||
fmt.Printf("\n")
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func BenchmarkECC(b *testing.B) {
|
||||
data := []byte{0x10, 0x20, 0x0c, 0x56, 0x61, 0x80, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0x10, 0x20, 0x0c, 0x56, 0x61, 0x80, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11, 0xec, 0x11}
|
||||
check := []byte{0x29, 0x41, 0xb3, 0x93, 0x8, 0xe8, 0xa3, 0xe7, 0x63, 0x8f}
|
||||
out := make([]byte, len(check))
|
||||
rs := NewRSEncoder(f, len(check))
|
||||
for i := 0; i < b.N; i++ {
|
||||
rs.ECC(data, out)
|
||||
}
|
||||
b.SetBytes(int64(len(data)))
|
||||
if !bytes.Equal(out, check) {
|
||||
fmt.Printf("have %#v want %#v\n", out, check)
|
||||
}
|
||||
}
|
||||
|
||||
func TestGen(t *testing.T) {
|
||||
for i := 0; i < 256; i++ {
|
||||
_, lg := f.gen(i)
|
||||
if lg[0] != 0 {
|
||||
t.Errorf("#%d: %x", i, lg)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestReducible(t *testing.T) {
|
||||
var count = []int{1, 2, 3, 6, 9, 18, 30, 56, 99, 186} // oeis.org/A1037
|
||||
for i, want := range count {
|
||||
n := 0
|
||||
for p := 1 << uint(i+2); p < 1<<uint(i+3); p++ {
|
||||
if !reducible(p) {
|
||||
n++
|
||||
}
|
||||
}
|
||||
if n != want {
|
||||
t.Errorf("#reducible(%d-bit) = %d, want %d", i+2, n, want)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestExhaustive(t *testing.T) {
|
||||
for poly := 0x100; poly < 0x200; poly++ {
|
||||
if reducible(poly) {
|
||||
continue
|
||||
}
|
||||
α := 2
|
||||
for !generates(α, poly) {
|
||||
α++
|
||||
}
|
||||
f := NewField(poly, α)
|
||||
for p := 0; p < 256; p++ {
|
||||
for q := 0; q < 256; q++ {
|
||||
fm := int(f.Mul(byte(p), byte(q)))
|
||||
pm := mul(p, q, poly)
|
||||
if fm != pm {
|
||||
t.Errorf("NewField(%#x).Mul(%#x, %#x) = %#x, want %#x", poly, p, q, fm, pm)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func generates(α, poly int) bool {
|
||||
x := α
|
||||
for i := 0; i < 254; i++ {
|
||||
if x == 1 {
|
||||
return false
|
||||
}
|
||||
x = mul(x, α, poly)
|
||||
}
|
||||
return true
|
||||
}
|
||||
|
|
@ -0,0 +1,400 @@
|
|||
// Copyright 2011 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package qrcode
|
||||
|
||||
// PNG writer for QR codes.
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"encoding/binary"
|
||||
"hash"
|
||||
"hash/crc32"
|
||||
)
|
||||
|
||||
// PNG returns a PNG image displaying the code.
|
||||
//
|
||||
// PNG uses a custom encoder tailored to QR codes.
|
||||
// Its compressed size is about 2x away from optimal,
|
||||
// but it runs about 20x faster than calling png.Encode
|
||||
// on c.Image().
|
||||
func (c *Code) PNG() []byte {
|
||||
var p pngWriter
|
||||
return p.encode(c)
|
||||
}
|
||||
|
||||
type pngWriter struct {
|
||||
tmp [16]byte
|
||||
wctmp [4]byte
|
||||
buf bytes.Buffer
|
||||
zlib bitWriter
|
||||
crc hash.Hash32
|
||||
}
|
||||
|
||||
var pngHeader = []byte("\x89PNG\r\n\x1a\n")
|
||||
|
||||
func (w *pngWriter) encode(c *Code) []byte {
|
||||
scale := c.Scale
|
||||
siz := c.Size
|
||||
|
||||
w.buf.Reset()
|
||||
|
||||
// Header
|
||||
w.buf.Write(pngHeader)
|
||||
|
||||
// Header block
|
||||
binary.BigEndian.PutUint32(w.tmp[0:4], uint32((siz+8)*scale))
|
||||
binary.BigEndian.PutUint32(w.tmp[4:8], uint32((siz+8)*scale))
|
||||
w.tmp[8] = 1 // 1-bit
|
||||
w.tmp[9] = 0 // gray
|
||||
w.tmp[10] = 0
|
||||
w.tmp[11] = 0
|
||||
w.tmp[12] = 0
|
||||
w.writeChunk("IHDR", w.tmp[:13])
|
||||
|
||||
// Comment
|
||||
w.writeChunk("tEXt", comment)
|
||||
|
||||
// Data
|
||||
w.zlib.writeCode(c)
|
||||
w.writeChunk("IDAT", w.zlib.bytes.Bytes())
|
||||
|
||||
// End
|
||||
w.writeChunk("IEND", nil)
|
||||
|
||||
return w.buf.Bytes()
|
||||
}
|
||||
|
||||
var comment = []byte("Software\x00QR-PNG <chaishushan{AT}gmail.com>")
|
||||
|
||||
func (w *pngWriter) writeChunk(name string, data []byte) {
|
||||
if w.crc == nil {
|
||||
w.crc = crc32.NewIEEE()
|
||||
}
|
||||
binary.BigEndian.PutUint32(w.wctmp[0:4], uint32(len(data)))
|
||||
w.buf.Write(w.wctmp[0:4])
|
||||
w.crc.Reset()
|
||||
copy(w.wctmp[0:4], name)
|
||||
w.buf.Write(w.wctmp[0:4])
|
||||
w.crc.Write(w.wctmp[0:4])
|
||||
w.buf.Write(data)
|
||||
w.crc.Write(data)
|
||||
crc := w.crc.Sum32()
|
||||
binary.BigEndian.PutUint32(w.wctmp[0:4], crc)
|
||||
w.buf.Write(w.wctmp[0:4])
|
||||
}
|
||||
|
||||
func (b *bitWriter) writeCode(c *Code) {
|
||||
const ftNone = 0
|
||||
|
||||
b.adler32.Reset()
|
||||
b.bytes.Reset()
|
||||
b.nbit = 0
|
||||
|
||||
scale := c.Scale
|
||||
siz := c.Size
|
||||
|
||||
// zlib header
|
||||
b.tmp[0] = 0x78
|
||||
b.tmp[1] = 0
|
||||
b.tmp[1] += uint8(31 - (uint16(b.tmp[0])<<8+uint16(b.tmp[1]))%31)
|
||||
b.bytes.Write(b.tmp[0:2])
|
||||
|
||||
// Start flate block.
|
||||
b.writeBits(1, 1, false) // final block
|
||||
b.writeBits(1, 2, false) // compressed, fixed Huffman tables
|
||||
|
||||
// White border.
|
||||
// First row.
|
||||
b.byte(ftNone)
|
||||
n := (scale*(siz+8) + 7) / 8
|
||||
b.byte(255)
|
||||
b.repeat(n-1, 1)
|
||||
// 4*scale rows total.
|
||||
b.repeat((4*scale-1)*(1+n), 1+n)
|
||||
|
||||
for i := 0; i < 4*scale; i++ {
|
||||
b.adler32.WriteNByte(ftNone, 1)
|
||||
b.adler32.WriteNByte(255, n)
|
||||
}
|
||||
|
||||
row := make([]byte, 1+n)
|
||||
for y := 0; y < siz; y++ {
|
||||
row[0] = ftNone
|
||||
j := 1
|
||||
var z uint8
|
||||
nz := 0
|
||||
for x := -4; x < siz+4; x++ {
|
||||
// Raw data.
|
||||
for i := 0; i < scale; i++ {
|
||||
z <<= 1
|
||||
if !c.Black(x, y) {
|
||||
z |= 1
|
||||
}
|
||||
if nz++; nz == 8 {
|
||||
row[j] = z
|
||||
j++
|
||||
nz = 0
|
||||
}
|
||||
}
|
||||
}
|
||||
if j < len(row) {
|
||||
row[j] = z
|
||||
}
|
||||
for _, z := range row {
|
||||
b.byte(z)
|
||||
}
|
||||
|
||||
// Scale-1 copies.
|
||||
b.repeat((scale-1)*(1+n), 1+n)
|
||||
|
||||
b.adler32.WriteN(row, scale)
|
||||
}
|
||||
|
||||
// White border.
|
||||
// First row.
|
||||
b.byte(ftNone)
|
||||
b.byte(255)
|
||||
b.repeat(n-1, 1)
|
||||
// 4*scale rows total.
|
||||
b.repeat((4*scale-1)*(1+n), 1+n)
|
||||
|
||||
for i := 0; i < 4*scale; i++ {
|
||||
b.adler32.WriteNByte(ftNone, 1)
|
||||
b.adler32.WriteNByte(255, n)
|
||||
}
|
||||
|
||||
// End of block.
|
||||
b.hcode(256)
|
||||
b.flushBits()
|
||||
|
||||
// adler32
|
||||
binary.BigEndian.PutUint32(b.tmp[0:], b.adler32.Sum32())
|
||||
b.bytes.Write(b.tmp[0:4])
|
||||
}
|
||||
|
||||
// A bitWriter is a write buffer for bit-oriented data like deflate.
|
||||
type bitWriter struct {
|
||||
bytes bytes.Buffer
|
||||
bit uint32
|
||||
nbit uint
|
||||
|
||||
tmp [4]byte
|
||||
adler32 adigest
|
||||
}
|
||||
|
||||
func (b *bitWriter) writeBits(bit uint32, nbit uint, rev bool) {
|
||||
// reverse, for huffman codes
|
||||
if rev {
|
||||
br := uint32(0)
|
||||
for i := uint(0); i < nbit; i++ {
|
||||
br |= ((bit >> i) & 1) << (nbit - 1 - i)
|
||||
}
|
||||
bit = br
|
||||
}
|
||||
b.bit |= bit << b.nbit
|
||||
b.nbit += nbit
|
||||
for b.nbit >= 8 {
|
||||
b.bytes.WriteByte(byte(b.bit))
|
||||
b.bit >>= 8
|
||||
b.nbit -= 8
|
||||
}
|
||||
}
|
||||
|
||||
func (b *bitWriter) flushBits() {
|
||||
if b.nbit > 0 {
|
||||
b.bytes.WriteByte(byte(b.bit))
|
||||
b.nbit = 0
|
||||
b.bit = 0
|
||||
}
|
||||
}
|
||||
|
||||
func (b *bitWriter) hcode(v int) {
|
||||
/*
|
||||
Lit Value Bits Codes
|
||||
--------- ---- -----
|
||||
0 - 143 8 00110000 through
|
||||
10111111
|
||||
144 - 255 9 110010000 through
|
||||
111111111
|
||||
256 - 279 7 0000000 through
|
||||
0010111
|
||||
280 - 287 8 11000000 through
|
||||
11000111
|
||||
*/
|
||||
switch {
|
||||
case v <= 143:
|
||||
b.writeBits(uint32(v)+0x30, 8, true)
|
||||
case v <= 255:
|
||||
b.writeBits(uint32(v-144)+0x190, 9, true)
|
||||
case v <= 279:
|
||||
b.writeBits(uint32(v-256)+0, 7, true)
|
||||
case v <= 287:
|
||||
b.writeBits(uint32(v-280)+0xc0, 8, true)
|
||||
default:
|
||||
panic("invalid hcode")
|
||||
}
|
||||
}
|
||||
|
||||
func (b *bitWriter) byte(x byte) {
|
||||
b.hcode(int(x))
|
||||
}
|
||||
|
||||
func (b *bitWriter) codex(c int, val int, nx uint) {
|
||||
b.hcode(c + val>>nx)
|
||||
b.writeBits(uint32(val)&(1<<nx-1), nx, false)
|
||||
}
|
||||
|
||||
func (b *bitWriter) repeat(n, d int) {
|
||||
for ; n >= 258+3; n -= 258 {
|
||||
b.repeat1(258, d)
|
||||
}
|
||||
if n > 258 {
|
||||
// 258 < n < 258+3
|
||||
b.repeat1(10, d)
|
||||
b.repeat1(n-10, d)
|
||||
return
|
||||
}
|
||||
if n < 3 {
|
||||
panic("invalid flate repeat")
|
||||
}
|
||||
b.repeat1(n, d)
|
||||
}
|
||||
|
||||
func (b *bitWriter) repeat1(n, d int) {
|
||||
/*
|
||||
Extra Extra Extra
|
||||
Code Bits Length(s) Code Bits Lengths Code Bits Length(s)
|
||||
---- ---- ------ ---- ---- ------- ---- ---- -------
|
||||
257 0 3 267 1 15,16 277 4 67-82
|
||||
258 0 4 268 1 17,18 278 4 83-98
|
||||
259 0 5 269 2 19-22 279 4 99-114
|
||||
260 0 6 270 2 23-26 280 4 115-130
|
||||
261 0 7 271 2 27-30 281 5 131-162
|
||||
262 0 8 272 2 31-34 282 5 163-194
|
||||
263 0 9 273 3 35-42 283 5 195-226
|
||||
264 0 10 274 3 43-50 284 5 227-257
|
||||
265 1 11,12 275 3 51-58 285 0 258
|
||||
266 1 13,14 276 3 59-66
|
||||
*/
|
||||
switch {
|
||||
case n <= 10:
|
||||
b.codex(257, n-3, 0)
|
||||
case n <= 18:
|
||||
b.codex(265, n-11, 1)
|
||||
case n <= 34:
|
||||
b.codex(269, n-19, 2)
|
||||
case n <= 66:
|
||||
b.codex(273, n-35, 3)
|
||||
case n <= 130:
|
||||
b.codex(277, n-67, 4)
|
||||
case n <= 257:
|
||||
b.codex(281, n-131, 5)
|
||||
case n == 258:
|
||||
b.hcode(285)
|
||||
default:
|
||||
panic("invalid repeat length")
|
||||
}
|
||||
|
||||
/*
|
||||
Extra Extra Extra
|
||||
Code Bits Dist Code Bits Dist Code Bits Distance
|
||||
---- ---- ---- ---- ---- ------ ---- ---- --------
|
||||
0 0 1 10 4 33-48 20 9 1025-1536
|
||||
1 0 2 11 4 49-64 21 9 1537-2048
|
||||
2 0 3 12 5 65-96 22 10 2049-3072
|
||||
3 0 4 13 5 97-128 23 10 3073-4096
|
||||
4 1 5,6 14 6 129-192 24 11 4097-6144
|
||||
5 1 7,8 15 6 193-256 25 11 6145-8192
|
||||
6 2 9-12 16 7 257-384 26 12 8193-12288
|
||||
7 2 13-16 17 7 385-512 27 12 12289-16384
|
||||
8 3 17-24 18 8 513-768 28 13 16385-24576
|
||||
9 3 25-32 19 8 769-1024 29 13 24577-32768
|
||||
*/
|
||||
if d <= 4 {
|
||||
b.writeBits(uint32(d-1), 5, true)
|
||||
} else if d <= 32768 {
|
||||
nbit := uint(16)
|
||||
for d <= 1<<(nbit-1) {
|
||||
nbit--
|
||||
}
|
||||
v := uint32(d - 1)
|
||||
v &^= 1 << (nbit - 1) // top bit is implicit
|
||||
code := uint32(2*nbit - 2) // second bit is low bit of code
|
||||
code |= v >> (nbit - 2)
|
||||
v &^= 1 << (nbit - 2)
|
||||
b.writeBits(code, 5, true)
|
||||
// rest of bits follow
|
||||
b.writeBits(uint32(v), nbit-2, false)
|
||||
} else {
|
||||
panic("invalid repeat distance")
|
||||
}
|
||||
}
|
||||
|
||||
func (b *bitWriter) run(v byte, n int) {
|
||||
if n == 0 {
|
||||
return
|
||||
}
|
||||
b.byte(v)
|
||||
if n-1 < 3 {
|
||||
for i := 0; i < n-1; i++ {
|
||||
b.byte(v)
|
||||
}
|
||||
} else {
|
||||
b.repeat(n-1, 1)
|
||||
}
|
||||
}
|
||||
|
||||
type adigest struct {
|
||||
a, b uint32
|
||||
}
|
||||
|
||||
func (d *adigest) Reset() { d.a, d.b = 1, 0 }
|
||||
|
||||
const amod = 65521
|
||||
|
||||
func aupdate(a, b uint32, pi byte, n int) (aa, bb uint32) {
|
||||
// TODO(rsc): 6g doesn't do magic multiplies for b %= amod,
|
||||
// only for b = b%amod.
|
||||
|
||||
// invariant: a, b < amod
|
||||
if pi == 0 {
|
||||
b += uint32(n%amod) * a
|
||||
b = b % amod
|
||||
return a, b
|
||||
}
|
||||
|
||||
// n times:
|
||||
// a += pi
|
||||
// b += a
|
||||
// is same as
|
||||
// b += n*a + n*(n+1)/2*pi
|
||||
// a += n*pi
|
||||
m := uint32(n)
|
||||
b += (m % amod) * a
|
||||
b = b % amod
|
||||
b += (m * (m + 1) / 2) % amod * uint32(pi)
|
||||
b = b % amod
|
||||
a += (m % amod) * uint32(pi)
|
||||
a = a % amod
|
||||
return a, b
|
||||
}
|
||||
|
||||
func afinish(a, b uint32) uint32 {
|
||||
return b<<16 | a
|
||||
}
|
||||
|
||||
func (d *adigest) WriteN(p []byte, n int) {
|
||||
for i := 0; i < n; i++ {
|
||||
for _, pi := range p {
|
||||
d.a, d.b = aupdate(d.a, d.b, pi, 1)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (d *adigest) WriteNByte(pi byte, n int) {
|
||||
d.a, d.b = aupdate(d.a, d.b, pi, n)
|
||||
}
|
||||
|
||||
func (d *adigest) Sum32() uint32 { return afinish(d.a, d.b) }
|
||||
|
|
@ -0,0 +1,69 @@
|
|||
// Copyright 2011 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package qrcode
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"image"
|
||||
"image/color"
|
||||
"image/png"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestPNG(t *testing.T) {
|
||||
c, err := Encode("hello, world", L)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
pngdat := c.PNG()
|
||||
m, err := png.Decode(bytes.NewBuffer(pngdat))
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
gm := m.(*image.Gray)
|
||||
|
||||
scale := c.Scale
|
||||
siz := c.Size
|
||||
nbad := 0
|
||||
for y := 0; y < scale*(8+siz); y++ {
|
||||
for x := 0; x < scale*(8+siz); x++ {
|
||||
v := byte(255)
|
||||
if c.Black(x/scale-4, y/scale-4) {
|
||||
v = 0
|
||||
}
|
||||
if gv := gm.At(x, y).(color.Gray).Y; gv != v {
|
||||
t.Errorf("%d,%d = %d, want %d", x, y, gv, v)
|
||||
if nbad++; nbad >= 20 {
|
||||
t.Fatalf("too many bad pixels")
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func BenchmarkPNG(b *testing.B) {
|
||||
c, err := Encode("0123456789012345678901234567890123456789", L)
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
var bytes []byte
|
||||
for i := 0; i < b.N; i++ {
|
||||
bytes = c.PNG()
|
||||
}
|
||||
b.SetBytes(int64(len(bytes)))
|
||||
}
|
||||
|
||||
func BenchmarkImagePNG(b *testing.B) {
|
||||
c, err := Encode("0123456789012345678901234567890123456789", L)
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
var buf bytes.Buffer
|
||||
for i := 0; i < b.N; i++ {
|
||||
buf.Reset()
|
||||
png.Encode(&buf, c.Image())
|
||||
}
|
||||
b.SetBytes(int64(buf.Len()))
|
||||
}
|
||||
|
|
@ -0,0 +1,114 @@
|
|||
// Copyright 2011 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// Package qrencoder implements a encoder for QR code.
|
||||
package qrcode
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"image"
|
||||
"image/color"
|
||||
|
||||
"github.com/chai2010/image/qrencoder/internal/coding"
|
||||
)
|
||||
|
||||
// A Level denotes a QR error correction level.
|
||||
// From least to most tolerant of errors, they are L, M, Q, H.
|
||||
type Level int
|
||||
|
||||
const (
|
||||
L Level = iota // 20% redundant
|
||||
M // 38% redundant
|
||||
Q // 55% redundant
|
||||
H // 65% redundant
|
||||
)
|
||||
|
||||
// Encode returns an encoding of text at the given error correction level.
|
||||
func Encode(text string, level Level) (*Code, error) {
|
||||
// Pick data encoding, smallest first.
|
||||
// We could split the string and use different encodings
|
||||
// but that seems like overkill for now.
|
||||
var enc coding.Encoding
|
||||
switch {
|
||||
case coding.Num(text).Check() == nil:
|
||||
enc = coding.Num(text)
|
||||
case coding.Alpha(text).Check() == nil:
|
||||
enc = coding.Alpha(text)
|
||||
default:
|
||||
enc = coding.String(text)
|
||||
}
|
||||
|
||||
// Pick size.
|
||||
l := coding.Level(level)
|
||||
var v coding.Version
|
||||
for v = coding.MinVersion; ; v++ {
|
||||
if v > coding.MaxVersion {
|
||||
return nil, errors.New("text too long to encode as QR")
|
||||
}
|
||||
if enc.Bits(v) <= v.DataBytes(l)*8 {
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
// Build and execute plan.
|
||||
p, err := coding.NewPlan(v, l, 0)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
cc, err := p.Encode(enc)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// TODO: Pick appropriate mask.
|
||||
|
||||
return &Code{cc.Bitmap, cc.Size, cc.Stride, 8}, nil
|
||||
}
|
||||
|
||||
// A Code is a square pixel grid.
|
||||
// It implements image.Image and direct PNG encoding.
|
||||
type Code struct {
|
||||
Bitmap []byte // 1 is black, 0 is white
|
||||
Size int // number of pixels on a side
|
||||
Stride int // number of bytes per row
|
||||
Scale int // number of image pixels per QR pixel
|
||||
}
|
||||
|
||||
// Black returns true if the pixel at (x,y) is black.
|
||||
func (c *Code) Black(x, y int) bool {
|
||||
return 0 <= x && x < c.Size && 0 <= y && y < c.Size &&
|
||||
c.Bitmap[y*c.Stride+x/8]&(1<<uint(7-x&7)) != 0
|
||||
}
|
||||
|
||||
// Image returns an Image displaying the code.
|
||||
func (c *Code) Image() image.Image {
|
||||
return &codeImage{c}
|
||||
|
||||
}
|
||||
|
||||
// codeImage implements image.Image
|
||||
type codeImage struct {
|
||||
*Code
|
||||
}
|
||||
|
||||
var (
|
||||
whiteColor color.Color = color.Gray{0xFF}
|
||||
blackColor color.Color = color.Gray{0x00}
|
||||
)
|
||||
|
||||
func (c *codeImage) Bounds() image.Rectangle {
|
||||
d := (c.Size + 8) * c.Scale
|
||||
return image.Rect(0, 0, d, d)
|
||||
}
|
||||
|
||||
func (c *codeImage) At(x, y int) color.Color {
|
||||
if c.Black(x, y) {
|
||||
return blackColor
|
||||
}
|
||||
return whiteColor
|
||||
}
|
||||
|
||||
func (c *codeImage) ColorModel() color.Model {
|
||||
return color.GrayModel
|
||||
}
|
||||
Loading…
Reference in New Issue