音视频解封装demo:将FLV文件解封装(demux)得到文件中的H264数据和AAC数据(纯手工,不依赖第三方开源库)

1、README

前言

注意:flv是不支持h.265封装的。目前解封装功能正常,所得到的H.264文件与AAC文件均可正常播放。

a. demo使用
$ make clean && make DEBUG=1
$ 
$ $ ./flv_demux_h264_aac 
Usage: ./flv_demux_h264_aac avfile/test1.flv./flv_demux_h264_aac avfile/test2.flv
b. 参考链接

【参考文章】

  • FLV格式详解_JT同学的博客-CSDN博客_flv格式**(推荐!!!)**

  • FLV封装格式介绍及解析 - 简书

  • 音视频封装:FLV格式详解和打包H264、AAC方案(上) - 云+社区 - 腾讯云

  • 音视频封装:FLV格式详解和打包H264、AAC方案(下) - 云+社区 - 腾讯云

【参考源码】

  • https://github.com/ImSjt/H.264toFLV.git

  • https://github.com/rainfly123/flvmuxer

【工具下载】

  • SpecialAAAC.exe:https://sourceforge.net/projects/aacstreamanalysis/

  • H264BSAnalyzer.exe:https://github.com/latelee/H264BSAnalyzer/tree/master/release

  • FlvParse.exe:https://github.com/ty6815/AvStackDocs/tree/master/media%20format/flv

c. demo目录架构
$ tree
.
├── aac_adts.c
├── aac_adts.h
├── avfile
│   ├── test1.aac
│   ├── test1.flv
│   ├── test1.h264
│   ├── test2.aac
│   ├── test2.flv
│   └── test2.h264
├── docs
│   ├── FLV封装格式介绍及解析 - 简书.mhtml
│   ├── FLV格式详解_JT同学的博客-CSDN博客_flv格式.mhtml
│   ├── 笔记---H.264里的SEI - 简书.mhtml
│   ├── 音视频封装:FLV格式详解和打包H264、AAC方案(上) - 云+社区 - 腾讯云.mhtml
│   └── 音视频封装:FLV格式详解和打包H264、AAC方案(下) - 云+社区 - 腾讯云.mhtml
├── flv.c
├── flv_format.h
├── flv.h
├── h264_nalu.h
├── main.c
├── Makefile
├── README.md
├── reference_code
│   └── Flv_to_h264_AAC_Demux.zip
└── tools├── FlvParse.exe├── H264BSAnalyzer.exe└── SpecialAAAC.exe

2、主要代码片段

flv_format.h
/**************************************************************** describe: Flv file format description(Mainly for H.264 & AAC)* author: linriming* e-mail: linriming20@163.com***************************************************************/#ifndef __FLV_FORMAT_H__
#define __FLV_FORMAT_H__#include <stdint.h>#define AUDIO_SUPPORT(x)    (x << 2)    /* bit[2] in flvheader's type_flag */
#define VIDEO_SUPPORT(x)    (x << 0)    /* bit[0] in flvheader's type_flag */#define SIZE_FLV_HEADER         sizeof(struct flvHeader)    /* 9 Bytes */
#define SIZE_FLV_TAG_HEADER     sizeof(struct flvTagHeader) /* 11 Bytes */
#define SIZE_PREVIOUS_TAG_SIZE  sizeof(uint32_t)            /* 4 Bytes *//* FLV tag type */
typedef enum{FLVTAG_TYPE_AUDIO  = 0x08,FLVTAG_TYPE_VIDEO  = 0x09,FLVTAG_TYPE_SCRIPT = 0x12,
}flvTagType;/* AMF data type in <Script Tag> */
typedef enum{AMF_DATA_TYPE_NUMBER      = 0x00,AMF_DATA_TYPE_BOOL        = 0x01,AMF_DATA_TYPE_STRING      = 0x02,AMF_DATA_TYPE_OBJECT      = 0x03,AMF_DATA_TYPE_NULL        = 0x05,AMF_DATA_TYPE_UNDEFINED   = 0x06,AMF_DATA_TYPE_REFERENCE   = 0x07,AMF_DATA_TYPE_MIXEDARRAY  = 0x08,AMF_DATA_TYPE_OBJECT_END  = 0x09,AMF_DATA_TYPE_ARRAY       = 0x0a,AMF_DATA_TYPE_DATE        = 0x0b,AMF_DATA_TYPE_LONG_STRING = 0x0c,AMF_DATA_TYPE_UNSUPPORTED = 0x0d,
} amfDataType;/* audio tag */
typedef enum{SFI_LINEAR_PCM_PLATFORM_ENDIAN = 0,SFI_ADPCM                      = 1,SFI_MP3                        = 2,SFI_LINEAR_PCM_LITTLE_ENDIAN   = 3,SFI_NELLYMOSER_16KHZ_MONO      = 4,SFI_NELLYMOSER_8KHZ_MONO       = 5,SFI_NELLYMOSER                 = 6,SFI_G711A                      = 7,SFI_G711MU                     = 8,SFI_RESERVED                   = 9,SFI_AAC                        = 10,SFI_SPEEX                      = 11,SFI_MP3_8KHZ                   = 14,SFI_DEVIVE_SPECIFIC_SOUND      = 15,
}soundFormatIndex;typedef enum{SRI_5_5KHZ = 0,SRI_11KHZ  = 1,SRI_22KHZ  = 2,SRI_44KHZ  = 3,
}soundSamplerateIndex;typedef enum{SSI_8BIT  = 0,SSI_16BIT = 1,
}soundSizeIndex;typedef enum{STI_MONO   = 0,STI_STEREO = 1,
}soundTypeIndex;#define  AAC_PACKET_TYPE_SEQUENCE_HEADER 	(0)
#define  AAC_PACKET_TYPE_RAW 				(1)typedef enum{AAC_MAIN = 1,AAC_LC   = 2,AAC_SSR  = 3,
}aacProfileIndex;typedef enum{AAC_96KHz = 0x0,AAC_88_2KHz = 0x1,AAC_64KHz = 0x2,AAC_48KHz = 0x3,AAC_44_1KHz = 0x4,AAC_32KHz = 0x5,AAC_24KHz = 0x6,AAC_22_05KHz = 0x7,AAC_16KHz  = 0x8,AAC_12KHz  = 0x9,AAC_11_025KHz  = 0xa,AAC_8KHz  = 0xb,AAC_RESERVED = 0xc,
}aacSamplerateIndex;typedef enum{AAC_CHANNEL_SPECIAL = 0x0,AAC_CHANNEL_MONO = 0x1,AAC_CHANNEL_STEREO = 0x2,AAC_CHANNEL_3 = 0x3,AAC_CHANNEL_4 = 0x4,AAC_CHANNEL_5 = 0x5,AAC_CHANNEL_5_1 = 0x6,AAC_CHANNEL_7_1 = 0x7,AAC_CHANNELRESERVED = 0x8,
}aacChannelIndex;#define  AVC_PACKET_TYPE_SEQUENCE_HEADER 			 (0)
#define  AVC_PACKET_TYPE_NALU 						 (1)
#define  AVC_PACKET_TYPE_END_OF_SEQUENCE 			 (2)/* next for video tag */
#define  VIDEOTAG_FRAMETYPE_KEYFRAME                 (1)
#define  VIDEOTAG_FRAMETYPE_INTER_FRAME              (2)
#define  VIDEOTAG_FRAMETYPE_DISPOSABLE_INTER_FRAME   (3)
#define  VIDEOTAG_FRAMETYPE_GENERATED_KEYFRAME       (4)
#define  VIDEOTAG_FRAMETYPE_VIDEO_INFO_FRAME         (5)#define  VIDEOTAG_CODECID_JPEG                       (1)
#define  VIDEOTAG_CODECID_SORENSON_H263              (2)
#define  VIDEOTAG_CODECID_SCREEN_VIDEO               (3)
#define  VIDEOTAG_CODECID_ON2_VP6                    (4)
#define  VIDEOTAG_CODECID_ON2_VP6_WITH_ALPHA_CHANNEL (5)
#define  VIDEOTAG_CODECID_SCREEN_VIDEO_VERSION_2     (6)
#define  VIDEOTAG_CODECID_AVC                        (7)#pragma pack(push)
#pragma pack(1)   /* 1 bytes align */typedef struct flvHeader{uint8_t  signature[3]; 		/* signature bytes always 'F' 'L' 'V': 0x46 0x4C 0x56 */uint8_t  version; 			/* file version, always 0x01 */uint8_t  type_flag; 		/* bit[7:3] and bit[1] always 0, bit[2] for aduio, bit[0] for video */uint32_t data_offset; 		/* size of header, 00 00 00 09(big-endian) for version 1 */
}T_FlvHeader, *PT_FlvHeader;   	    /* 9 bytes totally */typedef struct flvTagHeader{uint8_t TagType; 					/* Type of this tag. Value are 8(audio), 9(video), 18(script), other(reserved). */uint8_t DataSize[3]; 				/* Length of the data in the Data filed. */uint8_t Timestamp[3]; 				/* Time in milliseconds at which the data in this applies. 0 in first tag in the FLV file. */uint8_t TimestampExtended; 			/* Extension of Timestamp field to form a SI32 value, it is upper 8 bits. */uint8_t StreamID[3]; 				/* Always 0 */
}T_FlvTagHeader, *PT_FlvTagHeader; 	/* 11 bytes total */typedef struct flvTag{T_FlvTagHeader flvheader; 	/* tag header */uint8_t flvdata[0]; 		/* tag data index */
}T_FlvTag, *PT_FlvTag;typedef struct avcVideoPacket{T_FlvTagHeader flvheader;uint8_t flvdata[0]; 		/* flv tag data index */
}T_AvcVideoPacket, *PT_AvcVideoPacket;#pragma pack(pop)#endif /* __FLV_FORMAT_H__ */
flv.c
#include "h264_nalu.h"
#include "aac_adts.h"
#include "flv.h"int flv_demux_h264_aac(const char *flvFileName)
{FILE *fpH264 = NULL;FILE *fpAAC  = NULL;FILE *fpFLV  = NULL;uint8_t *flvBuf = NULL;// note!!!: it maybe happen the 'Segmentation fault', as 1024 is too long for 'sps', but it maybe save the 'sei' or other unused data if first nalu isn't 'sps'.uint8_t spsBuf[64] = {0};uint8_t ppsBuf[64] = {0};uint32_t spsLen = 0;uint32_t ppsLen = 0;int ret = -1;uint32_t flvTagDataSize = 0;PT_FlvTag ptFlvTag = NULL;const char *h264FileName = "out_video.h264";const char *aacFileName = "out_audio.aac";/* open file */fpFLV  = fopen(flvFileName,  "rb");if (!fpFLV){printf("open %s error!\n", flvFileName);}fpH264 = fopen(h264FileName, "wb");if (!fpH264){printf("open %s error!\n", h264FileName);}fpAAC  = fopen(aacFileName,  "wb");if (!fpAAC){printf("open %s error!\n", aacFileName);}/* alloc memory */flvBuf = (uint8_t *)malloc(MAX_FLV_BUF_SIZE);if (!flvBuf){printf("malloc for 'flvBuf' error!\n");}/* parse and save some data first. */fread(flvBuf, SIZE_FLV_HEADER, 1, fpFLV);ret = strncmp((const char *)flvBuf, "FLV", 3);if(ret != 0){printf("\033[31m It's not a FLV file!\n\033[0m");return -1;}DEBUG("\033[32m""=====================================\n""Signature: '%c' '%c' '%c'\n""Version  : 0x%02x\n""Audio    : %s\n""Video    : %s\n""=====================================\n""\033[0m",flvBuf[0], flvBuf[1], flvBuf[2], flvBuf[3], (flvBuf[4] & 0x04) ? "yes" : "no", (flvBuf[4] & 0x01) ? "yes" : "no");fread(flvBuf, SIZE_PREVIOUS_TAG_SIZE, 1, fpFLV);DEBUG("\033[37m[Pre Tag Size]: %d \033[0m\n", (flvBuf[0] << 24) |\(flvBuf[1] << 16) |\(flvBuf[2] <<  8) |\flvBuf[3]);while(1){ret = fread(flvBuf, SIZE_FLV_TAG_HEADER, 1, fpFLV);if (ret <= 0){DEBUG(">>> FLV file end! <<<\n");break;}ptFlvTag = (PT_FlvTag)flvBuf;flvTagDataSize = (ptFlvTag->flvheader.DataSize[0] << 16) |\(ptFlvTag->flvheader.DataSize[1] << 8) |\ptFlvTag->flvheader.DataSize[2];fread(ptFlvTag->flvdata, flvTagDataSize, 1, fpFLV);switch (ptFlvTag->flvheader.TagType){case FLVTAG_TYPE_SCRIPT: {DEBUG("\033[34m[Script Tag] \033[0m\n");/* nothing to do! */break;}case FLVTAG_TYPE_AUDIO: {char *packetTypeStr = NULL;int aacPacketType = ptFlvTag->flvdata[1];switch(aacPacketType){case AAC_PACKET_TYPE_SEQUENCE_HEADER:packetTypeStr = "[AAC sequence header]";/* nothing to do! */break;case AAC_PACKET_TYPE_RAW:packetTypeStr = "[AAC raw]";uint8_t headerbuf[AAC_ADTS_HEADER_SIZE] = {0};uint32_t headerbufLen = 0;uint32_t datasize = ((ptFlvTag->flvheader.DataSize[0] << 16) |\(ptFlvTag->flvheader.DataSize[1] << 8) |\ptFlvTag->flvheader.DataSize[2]);generateAdtsHeader(AAC_ADTS_HEADER_SIZE + (datasize - 2), headerbuf, &headerbufLen);fwrite(headerbuf, headerbufLen, 1, fpAAC);fwrite(&ptFlvTag->flvdata[2], datasize - 2, 1, fpAAC);break;default:printf("[%s:%d] Unknown AAC packet type!", __FUNCTION__, __LINE__);goto exit;}DEBUG("\033[36m[Audio Tag] \t %s\033[0m\n", packetTypeStr);break;}case FLVTAG_TYPE_VIDEO: {char *packetTypeStr = NULL;char *frameTypeStr = NULL;uint8_t startCode[4] = {0x00, 0x00, 0x00, 0x01};int isKeyFrame = 0;int type = 0;isKeyFrame = (ptFlvTag->flvdata[0] & 0xF0) == 0x10 ? 1 : 0;type = ptFlvTag->flvdata[1];switch(type){case AVC_PACKET_TYPE_SEQUENCE_HEADER:packetTypeStr = "[AVC squence header]";frameTypeStr = "[key frame]";spsLen = ((ptFlvTag->flvdata[11] << 8) | ptFlvTag->flvdata[12]);memcpy(spsBuf, &ptFlvTag->flvdata[13], spsLen);//printf("spsLen: %d\n", spsLen);//for(int i = 0; i < spsLen; i++)//	printf("0x%02x ", spsBuf[i]);//printf("\n");ppsLen = ((ptFlvTag->flvdata[13 + spsLen + 1] << 8) | ptFlvTag->flvdata[13+spsLen+2]);memcpy(ppsBuf, &ptFlvTag->flvdata[13 + spsLen + 3], ppsLen);//printf("ppsLen: %d\n", ppsLen);//for(int i = 0; i < ppsLen; i++)//	printf("0x%02x ", ppsBuf[i]);//printf("\n");break;case AVC_PACKET_TYPE_NALU:packetTypeStr = "[AVC NALU]";/* one or more NALU. */uint32_t naluDataSize = 0;uint32_t curPos = 0;curPos = 5;naluDataSize = (ptFlvTag->flvdata[curPos + 0] << 24) |\(ptFlvTag->flvdata[curPos + 1] << 16) |\(ptFlvTag->flvdata[curPos + 2] << 8) |\ptFlvTag->flvdata[curPos + 3];if(isKeyFrame){frameTypeStr = "[key frame]";if((ptFlvTag->flvdata[curPos + 4] & 0x1f) == NALU_TYPE_SEI &&\(ptFlvTag->flvdata[curPos + 5] & 0x1f) == 0x05/* SEI: payloadType: user_data_unregistered() */){/* has SEI *//* SEI */fwrite(startCode, sizeof(startCode), 1, fpH264);fwrite(&ptFlvTag->flvdata[curPos + 4], naluDataSize, 1, fpH264);/* SPS */fwrite(startCode, sizeof(startCode), 1, fpH264);fwrite(spsBuf, spsLen, 1, fpH264);/* PPS */fwrite(startCode, sizeof(startCode), 1, fpH264);fwrite(ppsBuf, ppsLen, 1, fpH264);/* update the second NALU data size. */curPos += (4 + naluDataSize);naluDataSize = (ptFlvTag->flvdata[curPos + 0] << 24) |\(ptFlvTag->flvdata[curPos + 1] << 16) |\(ptFlvTag->flvdata[curPos + 2] << 8) |\ptFlvTag->flvdata[curPos + 3];/* IDR */fwrite(startCode, sizeof(startCode), 1, fpH264);fwrite(&ptFlvTag->flvdata[curPos + 4], naluDataSize, 1, fpH264);}else{/* SPS */fwrite(startCode, sizeof(startCode), 1, fpH264);fwrite(spsBuf, spsLen, 1, fpH264);/* PPS */fwrite(startCode, sizeof(startCode), 1, fpH264);fwrite(ppsBuf, ppsLen, 1, fpH264);/* IDR */fwrite(startCode, sizeof(startCode), 1, fpH264);fwrite(&ptFlvTag->flvdata[curPos + 4], naluDataSize, 1, fpH264);}}else{frameTypeStr = "[inter frame]";/* SLICE */fwrite(startCode, sizeof(startCode), 1, fpH264);fwrite(&ptFlvTag->flvdata[curPos + 4], naluDataSize, 1, fpH264);}break;case AVC_PACKET_TYPE_END_OF_SEQUENCE:packetTypeStr = "[AVC end of squence]";frameTypeStr = "[key frame]";break;default:printf("[%s:%d] Unknown AVC packet type!", __FUNCTION__, __LINE__);goto exit;}DEBUG("\033[35m[Video Tag] \t %s \t %s\033[0m\n", packetTypeStr, frameTypeStr);break;}default: {printf("\033[33m[Unknown Tag]\033[0m\n");break;}}fread(flvBuf, SIZE_PREVIOUS_TAG_SIZE, 1, fpFLV);DEBUG("\033[37m[PreTagSize] \t %d\033[0m\n", (flvBuf[0] << 24) |\(flvBuf[1] << 16) |\(flvBuf[2] <<	8) |\flvBuf[3]);}exit:if(fpFLV) 	fclose(fpFLV);if(fpH264) 	{fflush(fpH264); fclose(fpH264);}if(fpAAC) 	{fflush(fpAAC); fclose(fpAAC);}if(flvBuf)  free(flvBuf);return 0;
}
main.c
#include <stdio.h>#include "flv.h"int main(int argc, char *argv[])
{if(argc == 1){printf("Usage: \n""   %s avfile/test1.flv\n""   %s avfile/test2.flv\n",argv[0], argv[0]);return -1;}flv_demux_h264_aac(argv[1]);printf("\033[32m""Success!\n""\033[0m");return 0;
}

3、demo下载地址(任选一个)

  • https://download.csdn.net/download/weixin_44498318/89526743
  • https://gitee.com/linriming/av_flv_demux_h264_aac.git
  • https://github.com/linriming20/av_flv_demux_h264_aac.git

本文来自互联网用户投稿,该文观点仅代表作者本人,不代表本站立场。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如若转载,请注明出处:http://www.mzph.cn/diannao/43996.shtml

如若内容造成侵权/违法违规/事实不符,请联系多彩编程网进行投诉反馈email:809451989@qq.com,一经查实,立即删除!

相关文章

压缩感知1——算法简介

传统的数据采集 传统的数字信号采样定律就是有名的香农采样定理&#xff0c;又称那奎斯特采样定律定理内容如下&#xff1a;为了不失真地恢复模拟信号&#xff0c;采样频率应该不小于模拟信号频谱中最高频率的2倍 上述步骤得到的数字信号的数据量比较大&#xff0c;一方面不利…

C语言程序题(一)

一.三个整数从大到小输出 首先做这个题目需要知道理清排序的思路&#xff0c;通过比较三个整数的值&#xff0c;使之从大到小输出。解这道题有很多方法我就总结了两种方法&#xff1a;一是通过中间变量比较和交换&#xff0c;二是可以用冒泡排序法&#xff08;虽然三个数字排序…

车载聚合路由器应用场景分析

乾元通QYT-X1z车载式1U多卡聚合路由器&#xff0c;支持最多8路聚合&#xff0c;无论是应急救援&#xff0c;还是车载交通&#xff0c;任何宽带服务商无法覆盖的区域&#xff0c;聚合路由器可提供现场需要的稳定、流畅、安全的视频传输网络&#xff0c;聚合路由器可无缝接入应急…

Dify中的weaviate向量数据库操作

一.安装weaviate客户端 1.Dify 0.6.9中weaviate信息 在Dify 0.6.9版本中weaviate容器信息如下: # The Weaviate vector store. weaviate:image: semitechnologies/weaviate:1.19.0restart: alwaysvolumes:# Mount the Weaviate data directory to the container.- ./volume…

【操作系统】进程管理——信号量机制(个人笔记)

学习日期&#xff1a;2024.7.9 内容摘要&#xff1a;信号量机制&#xff0c;用信号量实现进程的同步与互斥 信号量机制 信号量的概念 在上节内容中&#xff0c;我们学习了进程互斥的软件和硬件解决方案&#xff0c;但这些方案都有各自的问题&#xff0c;双标志法都因为检查和…

【自用】【高昆轮概率论与数理统计笔记】2.1 分布函数的概念与性质

不定期更新&#xff0c;前面的章节会在学完后补回来&#xff0c;重新学学概率&#xff0c;当年考研考的数学二&#xff0c;没有概率基础&#xff0c;想自己补补&#xff0c;视频课是高昆轮老师讲的浙大四版概率论教材的视频课&#xff0c;地址&#xff1a; 第一章&#xff1a;h…

数据库MySQL---基础篇

存储和管理数据的仓库 MySQL概述 数据库相关概念 数据库&#xff08;DataBase&#xff09;---数据存储的仓库&#xff0c;数据是有组织的进行存储 数据库管理系统&#xff08;DBMS&#xff09;-----操纵和管理数据库的大型软件 SQL----操作关系型数据库的编程语言&#xff…

Python:安装/Mac

之前一直陆陆续续有学python&#xff01;今天开始&#xff01;正式开肝&#xff01;&#xff01;&#xff01; 进入网站&#xff1a;可能会有点慢&#xff0c;多开几个网页 https://www.python.org 点击下载&#xff0c;然后进入新的页面&#xff0c;往下滑 来到File&#xff0…

实时温湿度监测系统:Micropython编码ESP32与DHT22模块的无线数据传输与PC端接收项目

实时温湿度监测系统 前言项目目的项目材料项目步骤模拟ESP32接线连接测试搭建PC端ESP32拷录环境对ESP32进行拷录PC端搭建桌面组件本地数据接收桌面小组件部分 实验总结 前言 人生苦短&#xff0c;我用Python。 由于我在日常工作中经常使用Python&#xff0c;因此在进行该项目…

基于java+springboot+vue实现的校园二手书交易平台(文末源码+Lw)287

摘 要 信息数据从传统到当代&#xff0c;是一直在变革当中&#xff0c;突如其来的互联网让传统的信息管理看到了革命性的曙光&#xff0c;因为传统信息管理从时效性&#xff0c;还是安全性&#xff0c;还是可操作性等各个方面来讲&#xff0c;遇到了互联网时代才发现能补上自…

Vue中v-for和v-if优先级(2、3)

Vue中v-for和v-if优先级&#xff08;2、3&#xff09; Vue2 在Vue2当中,v-for优先级要优于v-if,也就是说&#xff0c;当它俩同时沿用时&#xff0c;v-for先遍历&#xff0c;v-if再判断。 Vue2源码位置 \vue-dev\src\compiler\codegen\index.js export function genElement…

如何构建数据驱动的企业?爬虫管理平台是关键桥梁吗?

一、数据驱动时代&#xff1a;为何选择爬虫管理平台&#xff1f; 在信息爆炸的今天&#xff0c;数据驱动已成为企业发展的核心战略之一。爬虫管理平台&#xff0c;作为数据采集的第一站&#xff0c;它的重要性不言而喻。这类平台通过自动化手段&#xff0c;从互联网的各个角落…

windows的远程桌面连接docker

1. Docker容器中运行远程桌面服务 (RDP)&#xff1a;您的Docker容器需要安装和运行远程桌面服务。通常&#xff0c;远程桌面服务在Windows操作系统上可用。如果您使用的是Linux容器&#xff0c;则需要安装一个支持RDP协议的桌面环境和RDP服务器。 2. 开放RDP端口&#xff1a;通…

什么是RPC?有哪些RPC框架?

定义 RPC&#xff08;Remote Procedure Call&#xff0c;远程过程调用&#xff09;是一种允许运行在一台计算机上的程序调用另一台计算机上子程序的技术。这种技术屏蔽了底层的网络通信细节&#xff0c;使得程序间的远程通信如同本地调用一样简单。RPC机制使得开发者能够构建分…

【常见开源库的二次开发】一文学懂CJSON

简介&#xff1a; JSON&#xff08;JavaScript Object Notation&#xff09;是一种轻量级的数据交换格式。它基于JavaScript的一个子集&#xff0c;但是JSON是独立于语言的&#xff0c;这意味着尽管JSON是由JavaScript语法衍生出来的&#xff0c;它可以被任何编程语言读取和生成…

Django 实现子模版继承父模板

背景 Django的占位符&#xff0c;如果不继承父模板的内容&#xff0c;会被子模版所覆盖&#xff0c;有些业务场景子模版也需要使用到父模板中的内容 可以使用Django自带的标签{% block super %}来实现此效果 base.html 最基础html&#xff0c;相当于第一层html&#xff0c;bl…

代码随想录算法训练营day76 | Floyd 算法精讲、A * 算法精讲

本次题目来自于卡码网 ​​97. 小明逛公园 &#xff08;Floyd 算法精讲&#xff09; 1、确定dp数组以及下标的含义 grid[i][j][k] m&#xff0c;表示 节点i 到 节点j 以[1...k] 集合为中间节点的最短距离为m 2、确定递推公式 分两种情况&#xff1a; 节点i 到 节点j 的最…

01 | 基础架构:一条SQL查询语句是如何执行的?

此系列文章为极客时间课程《MySQL 实战 45 讲》的学习笔记&#xff01; 引言 在了解 SQL 查询语句如何执行之前&#xff0c;先了解下MySQL 的基本架构示意图。 MySQL 分为 Server 层和引擎层。 Server 层包括连接器、查询缓存、分析器、优化器、执行器等&#xff0c;涵盖 M…

微球无菌筛分技术的巅峰之作:纳维加特PV系列

在医药行业中&#xff0c;对微球的制备和筛分要求极高&#xff0c;纳维加特&#xff08;Navector&#xff09;凭借其自主创新的PV系列微球无菌旋振筛&#xff0c;成功突破这一领域的技术壁垒。该产品不仅拥有高效率、高精度的筛分能力&#xff0c;同时还兼顾了高卫生级别的要求…

uniapp自动升级

一、创建云服务空间&#xff08;https://unicloud.dcloud.net.cn&#xff09; 云空间用于关联需要版本控制升级的项目&#xff0c;如果已拥有云空间则省略此步骤。 二、搭建 uni升级中心 - 后台管理系统&#xff08;升级中心 uni-upgrade-center - Admin&#xff09; uni-adm…