#include <assert.h>
#include <stdlib.h>
#include "dmtx.h"
#include "dmtxstatic.h"

Functions
DmtxImage *	dmtxImageCreate (unsigned char *pxl, int width, int height, int pack)
	libdmtx stores image data as a large one-dimensional array of packed pixels, reading from the array when scanning barcodes and writing to it when creating a barcode.

DmtxPassFail	dmtxImageDestroy (DmtxImage **img)
	Free libdmtx image memory.

DmtxPassFail	dmtxImageSetChannel (DmtxImage *img, int channelStart, int bitsPerChannel)
	设置图像的颜色通道信息，包括每个通道的起始位和位数。

DmtxPassFail	dmtxImageSetProp (DmtxImage *img, int prop, int value)
	设置图像属性

int	dmtxImageGetProp (DmtxImage *img, int prop)
	获取图像属性

int	dmtxImageGetByteOffset (DmtxImage *img, int x, int y)
	根据给定的坐标 (x, y) 计算并返回图像中对应像素的字节偏移量

DmtxPassFail	dmtxImageGetPixelValue (DmtxImage img, int x, int y, int channel, int value)
	获取指定坐标的像素值

DmtxPassFail	dmtxImageSetPixelValue (DmtxImage *img, int x, int y, int channel, int value)
	设置指定坐标、通道的像素值

DmtxBoolean	dmtxImageContainsInt (DmtxImage *img, int margin, int x, int y)
	判断坐标 (x, y) 是否在图像范围内

DmtxBoolean	dmtxImageContainsFloat (DmtxImage *img, double x, double y)
	判断坐标 (x, y) 是否在图像范围内

static int	getBitsPerPixel (int pack)
	根据给定的打包方式（pack）返回每个像素所占的位数

Detailed Description

See LICENSE file in the main project directory for full terms of use and distribution.

Contact: Vadim A. Misbakh-Soloviov dmtx@.nosp@m.mva..nosp@m.name Mike Laughton mike@.nosp@m.drag.nosp@m.onfly.nosp@m.logi.nosp@m.c.com

Image handling

Definition in file dmtximage.c.

Function Documentation

◆ dmtxImageContainsFloat()

DmtxBoolean dmtxImageContainsFloat	(	DmtxImage *	img,
		double	x,
		double	y )

extern

判断坐标 (x, y) 是否在图像范围内

Parameters

[in]	img
[in]	x	coordinate
[in]	y	coordinate

Returns: DmtxTrue | DmtxFalse

Definition at line 404 of file dmtximage.c.

◆ dmtxImageContainsInt()

DmtxBoolean dmtxImageContainsInt	(	DmtxImage *	img,
		int	margin,
		int	x,
		int	y )

extern

判断坐标 (x, y) 是否在图像范围内

Parameters

[in]	img
[in]	margin	width
[in]	x	coordinate
[in]	y	coordinate

Returns: DmtxTrue | DmtxFalse

Definition at line 386 of file dmtximage.c.

◆ dmtxImageCreate()

DmtxImage * dmtxImageCreate	(	unsigned char *	pxl,
		int	width,
		int	height,
		int	pack )

extern

libdmtx stores image data as a large one-dimensional array of packed pixels, reading from the array when scanning barcodes and writing to it when creating a barcode.

Beyond this interaction the calling program is responsible for populating and dispatching pixels between the image array and the outside world, whether that means loading an image from a file, acquiring camera input, displaying output to a screen, saving to disk, etc...

By default, libdmtx treats the first pixel of an image array as the top-left corner of the physical image, with the final pixel landing at the bottom- right. However, if mapping a pixel buffer this way produces an inverted image the calling program can specify DmtxFlipY at image creation time to remove the inversion. This has a negligible effect on performance since it only modifies the pixel mapping math, and does not alter any pixel data.

Regardless of how an image is stored internally, all libdmtx functions consider coordinate (0,0) to mathematically represent the bottom-left pixel location of an image using a right-handed coordinate system.

libdmtx 将图像数据存储为一个大型一维数组，扫描条形码时从数组中读取，创建条形码时向数组中写入。除了这种交互，调用程序还负责在图像数组和外部世界之间填充和调度像素，无论是从文件中加载图像、获取摄像头输入、向屏幕显示输出、保存到磁盘等。

默认情况下，libdmtx 将图像数组的第一个像素视为物理图像的左上角，最后一个像素位于右下角。不过，如果以这种方式映射像素缓冲区会产生反转图像，调用程序可以在创建图像时指定 DmtxFlipY 来消除反转。这对性能的影响可以忽略不计，因为它只修改了像素映射数学，而不会改变任何像素数据。

无论图像内部如何存储，所有 libdmtx 函数都认为坐标（0,0）在数学上代表使用右手坐标系的图像左下角像素位置。

           (0,HEIGHT-1)        (WIDTH-1,HEIGHT-1)

     array pos = 0,1,2,3,...-----------+
                 |                     |
                 |                     |
                 |       libdmtx       |
                 |        image        |
                 |     coordinates     |
                 |                     |
                 |                     |
                 +---------...,N-2,N-1,N = array pos

               (0,0)              (WIDTH-1,0)

Notes:

OpenGL pixel arrays obtained with glReadPixels() are stored bottom-to-top; use DmtxFlipY
Many popular image formats (e.g., PNG, GIF) store rows top-to-bottom; use DmtxFlipNone

创建一个新的图像对象

Note: 创建的图像对象需要在不再使用时通过调用 dmtxImageDestroy 进行销毁。

Definition at line 78 of file dmtximage.c.

◆ dmtxImageDestroy()

DmtxPassFail dmtxImageDestroy ( DmtxImage ** img )

extern

Free libdmtx image memory.

Parameters

[in] img pointer to img location

Returns: DmtxFail | DmtxPass

Definition at line 167 of file dmtximage.c.

◆ dmtxImageGetByteOffset()

int dmtxImageGetByteOffset	(	DmtxImage *	img,
		int	x,
		int	y )

extern

根据给定的坐标 (x, y) 计算并返回图像中对应像素的字节偏移量

Definition at line 263 of file dmtximage.c.

◆ dmtxImageGetPixelValue()

DmtxPassFail dmtxImageGetPixelValue	(	DmtxImage *	img,
		int	x,
		int	y,
		int	channel,
		int *	value )

extern

获取指定坐标的像素值

此函数用于获取图像中指定坐标 (x, y) 处特定颜色通道的像素值。如果坐标超出图像边界或通道索引无效，则返回失败。

Parameters

[in]	img	指向图像对象的指针
[in]	x	像素的 X 轴坐标
[in]	y	像素的 Y 轴坐标
[in]	channel	要获取值的颜色通道索引
[out]	value	用于存储像素值的指针

Returns: 返回 DmtxPass 表示成功，DmtxFail 表示失败

Definition at line 293 of file dmtximage.c.

◆ dmtxImageGetProp()

int dmtxImageGetProp	(	DmtxImage *	img,
		int	prop )

extern

获取图像属性

Returns: 失败返回 DmtxUndefined

Definition at line 228 of file dmtximage.c.

◆ dmtxImageSetChannel()

DmtxPassFail dmtxImageSetChannel	(	DmtxImage *	img,
		int	channelStart,
		int	bitsPerChannel )

extern

设置图像的颜色通道信息，包括每个通道的起始位和位数。

Definition at line 183 of file dmtximage.c.

◆ dmtxImageSetPixelValue()

DmtxPassFail dmtxImageSetPixelValue	(	DmtxImage *	img,
		int	x,
		int	y,
		int	channel,
		int	value )

extern

设置指定坐标、通道的像素值

Definition at line 337 of file dmtximage.c.

◆ dmtxImageSetProp()

DmtxPassFail dmtxImageSetProp	(	DmtxImage *	img,
		int	prop,
		int	value )

extern

设置图像属性

Definition at line 203 of file dmtximage.c.

◆ getBitsPerPixel()

static int getBitsPerPixel ( int pack )

static

根据给定的打包方式（pack）返回每个像素所占的位数

Definition at line 418 of file dmtximage.c.

Functions

Detailed Description

Function Documentation

◆ dmtxImageContainsFloat()

◆ dmtxImageContainsInt()

◆ dmtxImageCreate()

◆ dmtxImageDestroy()

◆ dmtxImageGetByteOffset()

◆ dmtxImageGetPixelValue()

◆ dmtxImageGetProp()

◆ dmtxImageSetChannel()

◆ dmtxImageSetPixelValue()

◆ dmtxImageSetProp()

◆ getBitsPerPixel()