使用 Zint 库生成 QR Code 二维码

介绍

QR 码（Quick Response Code）

维基百科

结构

尺寸

​ Version 1 为 21 × 21 矩阵，Version 每增加 1 ，尺寸增加 4 ，公式为:(V - 1) * 4 + 21。Version 最高为40，即矩阵最大尺寸为 177 × 177。

存储

​ Maximum character storage capacity (40-L)

Input mode	max. characters	bits/char	possible characters, default encoding
Numeric only	7,089	3⅓	0, 1, 2, 3, 4, 5, 6, 7, 8, 9
Alphanumeric	4,296	5½	0–9, A–Z (upper-case only), space, $, %, *, +, -, ., /, :
Binary/byte	2,953	8	ISO 8859-1
Kanji/kana	1,817	13	Shift JIS X 0208

容错能力

错误修正容量
L水平	7%的字码可被修正
M水平	15%的字码可被修正
Q水平	25%的字码可被修正
H水平	30%的字码可被修正

阅读

二维码的生成细节和原理

Zint

地址

Github-zint

Zint Barcode Generator

编译

编译 zint 之前需先编译 zlib 和 libpng。

• 到 http://www.zlib.net/ 下载 zlib 源码，到 http://www.libpng.org/pub/png/libpng.html 下载 libpng 源码。

• 在 D 盘新建 opt 文件夹，在之下新建 include 与 lib 文件夹。

• 将 zlib 与 libpng 源码解压至 opt 目录下。

• 编译 libpng，完成后，拷贝

  libpng16.exp、libpng16.lib、zlib.lib

  至 D:\opt\lib，将 zlib 与 libpng 目录下 .h 文件拷贝至 D:\opt\include。

• 打开 zint 项目，将附加依赖项中的 libpng13.lib 和 zlib1.lib 修改为 libpng16.lib 和 zlib.lib ，在 libzint 项目中的 png.c 添加

  include

• 删除 libzint 项目中的 dm200.c 和 dm200.h。

• 右键 libzint 项目，生成。

API

创建和删除 Symbols

#include 
#include 
int main() {
    struct zint_symbol *my_symbol;
    my_symbol = ZBarcode_Create();
    if (my_symbol != NULL) {
        printf("Symbol successfully created!\n");
    }
    ZBarcode_Delete(my_symbol);
    return 0;
}

编码并保存到文件

#include 
#include 
int main(int argc, char **argv) {
    struct zint_symbol *my_symbol;
    my_symbol = ZBarcode_Create();
    ZBarcode_Encode(my_symbol, argv[1], 0);
    ZBarcode_Print(my_symbol, 0);
    ZBarcode_Delete(my_symbol);
    return 0;
}

#include 
#include 
int main(int argc, char **argv) {
    struct zint_symbol *my_symbol;
    my_symbol = ZBarcode_Create();
    ZBarcode_Encode_and_Print(my_symbol, argv[1], 0, 0);
    ZBarcode_Delete(my_symbol);
    return 0;
}

设置选项

Variable Name	Type	Meaning	Default Value
symbology	integer	Symbology to use.	BARCODE_CODE128
height	integer	Symbol height.	50
whitespace_width	integer	Whitespace width.	0
boder_width	integer	Border width.	0
output_options	integer	Binding or box parameters.	(none)
fgcolour	character string	Foreground (ink) colour as RGB hexadecimal string. Must be 6 characters followed by terminating \0 character.	"000000"
bgcolour	character string	Background (paper) colour as RGB hexadecimal string. Must be 6 characters followed by terminating \0 character.	"ffffff"
outfile	character string	Contains the name of the file to output a resulting barcode symbol to. Must end in .png, .eps or .svg	"out.png"
option_1	integer	Symbology specific options.	(automatic)
option_2	integer	Symbology specific options.	(automatic)
option_3	integer	Symbology specific options.	(automatic)
scale	float	Scale factor for adjusting size of image.	1.0
input_mode	integer	Set encoding of input data.	BINARY_MODE
primary	character string	Primary message data for more complex symbols.	NULL
text	unsigned character string	Human readable text, which usually consists of the input data plus one or more check digits. Uses UTF-8 formatting.	NULL
rows	integer	Number of rows used by the symbol or, if using barcode stacking, the row to be used by the next symbol.	(output only)
width	integer	Width of the generated symbol.	(output only)
encoding_data	array of character strings	Representation of the encoded data.	(output only)
row_height	array of integers	Representation of the height of a row.	(output only)
errtxt	character string	Error message in the event that an error occurred.	(output only)
bitmap	pointer to character array	Pointer to stored bitmap image.	(output only)
bitmap_width	integer	Width of stored bitmap image (in pixels).	(output only)
bitmap_height	integer	Height of stored bitmap image (in pixels).	(output only)

错误处理

Return Value	Meaning
WARN_INVALID_OPTION	One of the values in zint_struct was set incorrectly but Zint has made a guess at what it should have been and generated a barcode accordingly.
ERROR_TOO_LONG	The input data is too long or too short for the selected symbology. No symbol has been generated.
ERROR_INVALID_DATA	The data to be encoded includes characters which are not permitted by the selected symbology (e.g. alphabetic characters in an EAN symbol). No symbol has been generated.
ERROR_INVALID_CHECK	An ISBN with an incorrect check digit has been entered. No symbol has been generated.
ERROR_INVALID_OPTION	One of the values in zint_struct was set incorrectly and Zint was unable to guess what it should have been. No symbol has been generated.
ERROR_ENCODING_PROBLEM	A problem has occurred during encoding of the data. This should never happen. Please contact the developer if you encounter this error.
ERROR_FILE_ACCESS	Zint was unable to open the requested output file. This is usually a file permissions problem.
ERROR_MEMORY	Zint ran out of memory. This should only be a problem with legacy systems.

#include 
#include 
#include 
int main(int argc, char **argv) {
    struct zint_symbol *my_symbol;
    int error = 0;
    my_symbol = ZBarcode_Create();
    strcpy(my_symbol->fgcolour, "nonsense");
    error = ZBarcode_Encode_and_Print(my_symbol, argv[1], 0, 0);
    if (error != 0) {
        /* some error occurred */
        printf("%s\n", my_symbol->errtxt);
    }
    if (error > WARN_INVALID_OPTION) {
        /* stop now */
        ZBarcode_Delete(my_symbol);
        return 1;
    }
    /* otherwise carry on with the rest of the application */
    ZBarcode_Delete(my_symbol);
    return 0;
}

指定 Symbology

Symbology 可以被指定为名称或者是数字。

例如 symbol->symbology = BARCODE_LOGMARS; 与 symbol->symbology = 50; 等价。

QR Code 为：58 BARCODE_QRCODE

设置输入模式

Value	Effect
DATA_MODE	Uses full ASCII range interpreted as Latin-1 or binary data.
UNICODE_MODE	Uses pre-formatted UTF-8 input.
GS1_MODE	Encodes GS1 data using FNC1 characters.

参考

https://en.wikipedia.org/wiki/QR_code

http://coolshell.cn/articles/10590.html

https://github.com/downloads/zint/zint/zint_manual_242.pdf