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视频抓图

提供 JPEG 格式抓图功能,包括返回图片二进制数据、图像文件直接存储。

接口概览

接口名称 功能描述
NET_SDK_CaptureJPEGData_V2 JPEG 格式抓图接口,JPEG 数据保存在数据缓存区。
NET_SDK_CaptureJPEGFile_V2 JPEG 格式抓图接口,图像直接保存为文件格式。
NET_SDK_CaptureJPEGPicture 抓取 JPEG 格式图片并保存,JPEG 数据保存在数据缓存区。仅 win 版本支持,在解码库中抓图。
NET_SDK_RemoteSnap 控制远程设备抓图,图片保存设备本地。(仅 N9000 支持)
NET_SDK_SearchPictures 获取远程设备的图片列表。(仅 N9000 设备)
NET_SDK_DownLoadPicture 下载 NET_SDK_SearchPictures 搜索到的远程图片,数据保存在缓存区。(仅 N9000 生效)

流程说明

---
title: 视频抓图
---
flowchart TD
    A(设备SDK初始化<br><strong>NET_SDK_Init</strong>)
    B(用户注册设备<br><strong>NET_SDK_Login</strong>或<br><strong>NET_SDK_LoginEx</strong>)

    C("截取JPEG图片数据<br><strong>NET_SDK_CaptureJPEGData_V2</strong>")
    D("截取JPEG图片文件<br><strong>NET_SDK_CaptureJPEGFile_V2</strong>")
    E("...")
    F("搜索图片<br><strong>NET_SDK_SearchPictures</strong>")
    G("下载搜索到的图片<br><strong>NET_SDK_DownloadPicture</strong>")

    Y(注销设备<br><strong>NET_SDK_Logout</strong>)
    Z(释放SDK资源<br><strong>NET_SDK_Cleanup</strong>)


    A --> B
    Y --> Z
    B ---> C ---> Y
    B ---> D ---> Y
    B ---> E ---> Y
    B ---> F ---> Y
    B ---> G ---> Y


示例代码

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#include <afx.h>
#include <string>
#include <stdio.h>
#include <iostream>
#include "DVR_NET_SDK.h"

void CaptureJPEGData()
{
    // Device information.
    const std::string device_ip = "10.80.1.177";
    const DWORD decice_port = 6036;
    const std::string username = "admin";
    const std::string password = "123456";
    // Initialize SDK.
    NET_SDK_Init();
    NET_SDK_DEVICEINFO device_info{0};
    DWORD errCode = 0;
    // Device login.
    int userid = NET_SDK_Login(const_cast<char *>(device_ip.c_str()), decice_port, const_cast<char *>(username.c_str()), const_cast<char *>(password.c_str()), &device_info);

    if (userid > 0)
    {
        std::cout << "Login successful!" << std::endl;
    }
    else
    {
        errCode = NET_SDK_GetLastError();
        std::cout << "Login failed!" << "Error code:" << errCode << std::endl;
        NET_SDK_Cleanup();
        return;
    }

    // Get the screenshot data and save it to the local disk.
    DWORD dwRetLen = 0;
    const int nJpgBufLen = 1024 * 1024 * 5;
    char *pJpegBuf = new char[nJpgBufLen];
    memset(pJpegBuf, 0x00, nJpgBufLen);
    char imgName[512]{0};
    sprintf_s(imgName, "D:/test.jpg");
    BOOL captureStatus = NET_SDK_CaptureJPEGData_V2(userid, 0, pJpegBuf, nJpgBufLen, &dwRetLen);

    if (!captureStatus)
    {
        errCode = NET_SDK_GetLastError();
        std::cout << "Screenshot failed!" << "Error code:" << errCode << std::endl;
    }
    else
    {
        FILE *file;
        errno_t err = fopen_s(&file, imgName, "wb");

        if (err = 0 || file != NULL)
        {
            fwrite(pJpegBuf, sizeof(char), dwRetLen, file);
            fclose(file);
            std::cout << "Screenshot successful!" << std::endl;
        }
        else
        {
            std::cout << "Screenshot failed! write file failed!" << std::endl;
        }
    }

    // Logout.
    NET_SDK_Logout(userid);
    // Release SDK resources.
    NET_SDK_Cleanup();
    return;
}
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#include <afx.h>
#include <string>
#include <stdio.h>
#include <iostream>
#include "DVR_NET_SDK.h"

void CaptureJPEGFile()
{
    // Device information.
    const std::string device_ip = "10.80.1.177";
    const DWORD decice_port = 6036;
    const std::string username = "admin";
    const std::string password = "123456";
    // Initialize SDK.
    NET_SDK_Init();
    NET_SDK_DEVICEINFO device_info{0};
    DWORD errCode = 0;
    // Device login.
    int userid = NET_SDK_Login(const_cast<char *>(device_ip.c_str()), decice_port, const_cast<char *>(username.c_str()), const_cast<char *>(password.c_str()), &device_info);

    if (userid > 0)
    {
        std::cout << "Login successful!" << std::endl;
    }
    else
    {
        errCode = NET_SDK_GetLastError();
        std::cout << "Login failed!" << "Error code:" << errCode << std::endl;
        NET_SDK_Cleanup();
        return;
    }

    // Save the screenshot directly to the local disk.
    char imgName[512]{0};
    sprintf_s(imgName, "D:/test.jpg");
    BOOL captureStatus = NET_SDK_CaptureJPEGFile_V2(userid, 0, imgName);

    if (!captureStatus)
    {
        errCode = NET_SDK_GetLastError();
        std::cout << "Screenshot failed!" << "Error code:" << errCode << std::endl;
    }
    else
    {
        std::cout << "Screenshot successful!" << std::endl;
    }

    // Logout.
    NET_SDK_Logout(userid);
    // Release SDK resources.
    NET_SDK_Cleanup();
    return;
}
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