1

.vscode/c_cpp_properties.json

@@ -0,0 +1,18 @@
+{
+    "configurations": [
+        {
+            "name": "Linux",
+            "includePath": [
+                "${workspaceFolder}/**",
+                "/usr/local/ffmpeg/include",
+                "${workspaceFolder}/libs_win/develop/SDL2-2.0.9/include"
+            ],
+            "defines": [],
+            "compilerPath": "/usr/bin/gcc",
+            "cStandard": "c17",
+            "cppStandard": "c++98",
+            "intelliSenseMode": "linux-gcc-x64"
+        }
+    ],
+    "version": 4
+}

.vscode/launch.json

@@ -0,0 +1,36 @@
+{
+    // 使用 IntelliSense 了解相关属性。 
+    // 悬停以查看现有属性的描述。
+    // 欲了解更多信息，请访问: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+        {//包含Debug配置
+            "name": "(gdb) 启动",//配置名称
+            "type": "cppdbg",//配置类型,对应cpptools提供的调试功能
+            "request": "launch",//请求配置类型,可以是启动/附加类型[launch/attach]
+            "program": "${workspaceFolder}/study_ffmpeg/7_/${fileBasenameNoExtension}",//待调试程序本地路径
+            "args": [//程序调试时传递给程序的命令行参数,设为空值
+                "build_avdio.h264",
+                "libx264"
+            ],
+            "stopAtEntry": false,//改为true时程序暂停在程序入口位置,即main处打上断点
+            "cwd": "${fileDirname}",//调试程序时的工作目录,这里表示源码目录
+            "environment": [],//环境变量,设为空值
+            "externalConsole": false,//true:cmd窗口; false:Vscode的内置终端输出
+            "MIMode": "gdb",//指定连接的调试器,minGW64中调试程序->gdb
+            "setupCommands": [
+                {
+                    "description": "为 gdb 启用整齐打印",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                },
+                {
+                    "description": "将反汇编风格设置为 Intel",
+                    "text": "-gdb-set disassembly-flavor intel",
+                    "ignoreFailures": true
+                }
+            ]
+        },
+    ]
+}

.vscode/settings.json

@@ -0,0 +1,11 @@
+{
+    "C_Cpp.errorSquiggles": "enabled",
+    "files.associations": {
+        "stdio.h": "c",
+        "log.h": "c",
+        "gen_pic_rgb": "c",
+        "sdl.h": "c",
+        "avcodec.h": "c",
+        "avutil.h": "c"
+    }
+}

.vscode/tasks.json

@@ -0,0 +1,37 @@
+{
+    "tasks": [
+        {//构建配置项
+            "type": "cppbuild", //任务类型,Vscode将预定义变量转义解析后直接传给command;shell->先打开shell再输入命令,因此args会经过shell再次解析
+            "label": "C/C++: gcc 生成活动文件", //任务名称
+            "command": "/usr/bin/gcc",//本地编译器路径
+            "args": [//包含传给gcc命令的参数,用于实现特定功能
+                "-g",//生成和调试有关的信息
+                "${file}",//指定编译文件为当前文件
+                "-o",//指定输出文件的路径和名称
+                "${fileDirname}/${fileBasenameNoExtension}",//修改.exe文件生成位置
+                "-lm",
+                "-I/usr/local/ffmpeg/include",
+                "-L/usr/local/ffmpeg/lib",
+                "-I/${workspaceFolder}/libs_win/develop/SDL2-2.0.9/include",
+                "-L/${workspaceFolder}/libs_win/develop/SDL2-2.0.9/lib",
+                "-lavutil",
+                "-lavformat",
+                "-lavcodec",
+                "-lswscale",
+                "-lSDL2"
+            ],
+            "options": {
+                "cwd": "${fileDirname}"
+            },
+            "problemMatcher": [
+                "$gcc"
+            ],
+            "group": {//包含很多task,归为group
+                "kind": "build",//表名该组任务类型是构建
+                "isDefault": true//表明此任务为此组任务中的默认任务
+            },
+            "detail": "调试器生成的任务。"
+        },
+    ],
+    "version": "2.0.0"
+}

audio.c

@@ -1,6 +1,7 @@
 #include "player.h"
 #include "packet.h"
 #include "frame.h"
+#include "SDL_audio.h"
 
 static void sdl_audio_callback(void *opaque, Uint8 *stream, int len);
 

demux.c

@@ -1,5 +1,7 @@
 #include "demux.h"
 #include "packet.h"
+#include "SDL_events.h"
+#include "SDL_mutex.h"
 
 static int decode_interrupt_cb(void *ctx)
 {

study_ffmpeg/5_/cut_avdio.c

@@ -0,0 +1,195 @@
+#include<stdio.h>
+#include<stdlib.h>
+#include<libavutil/log.h>
+#include<libavutil/avutil.h>
+#include<libavformat/avformat.h>
+
+int main(int argc, char* argv[])
+{
+    // 1.处理一些参数；
+    int ret = -1;
+    char* src;
+    char* dst;
+    double starttime;
+    double endtime;
+
+    av_log_set_level(AV_LOG_DEBUG);
+    // cut src dst start end
+    if( argc < 5 ) {
+        av_log(NULL, AV_LOG_INFO, "arguments must be more than 3\n");
+        exit(-1);
+    }
+
+    src = argv[1];
+    dst = argv[2];
+    starttime = atof(argv[3]);
+    endtime = atof(argv[4]);
+
+
+    // 2.打开多媒体文件；
+
+    AVFormatContext *pFmtCtx = NULL;
+    if( (ret = avformat_open_input(&pFmtCtx, src, NULL, NULL)) < 0 ){
+        av_log(NULL, AV_LOG_ERROR, "%s\n", av_err2str(ret));
+        exit(-1);
+    }
+
+    // 4.打开目的文件的上下文
+    // AVFormatContext *oFmtCtx = avformat_alloc_context();
+    // if( !oFmtCtx ){
+    //     av_log(NULL, AV_LOG_ERROR, "NO Memory!\n");
+    //     goto _ERROR;
+    // } 
+    // const AVOutputFormat *outFmt = av_guess_format(NULL, dst, NULL);
+    // oFmtCtx->oformat = outFmt;
+    AVFormatContext *oFmtCtx = NULL;
+    avformat_alloc_output_context2(&oFmtCtx, NULL, NULL, dst);
+    if( !oFmtCtx ){
+        av_log(NULL, AV_LOG_ERROR, "NO MEMORT!\n");
+        goto _ERROR;
+    } 
+
+    int *stream_map = NULL;
+    int stream_idx = 0;
+    stream_map = av_calloc(pFmtCtx->nb_streams, sizeof(int));
+    if( !stream_map ){
+        av_log(NULL, AV_LOG_ERROR, "NO MEMORT!\n");
+        goto _ERROR;
+    }
+    for( int i=0 ; i < pFmtCtx->nb_streams ; i++ ){
+        AVStream *inStream = pFmtCtx->streams[i];
+        AVStream *outStream = NULL;
+        AVCodecParameters *inCodecPar = inStream->codecpar;
+        if( inCodecPar->codec_type != AVMEDIA_TYPE_AUDIO && 
+            inCodecPar->codec_type != AVMEDIA_TYPE_VIDEO && 
+            inCodecPar->codec_type != AVMEDIA_TYPE_SUBTITLE){
+            stream_map[i] = -1;
+            continue;
+        }
+        else{
+            stream_map[i] = stream_idx++ ;
+            outStream = avformat_new_stream(oFmtCtx, NULL);
+            if( !outStream ){
+                av_log(oFmtCtx, AV_LOG_ERROR, "NO MEMORT!\n");
+                goto _ERROR;
+            }
+            avcodec_parameters_copy(outStream->codecpar, inStream->codecpar);
+            outStream->codecpar->codec_tag = 0;
+        }
+    }
+
+
+    // 绑定
+    ret = avio_open2(&oFmtCtx->pb, dst, AVIO_FLAG_WRITE, NULL, NULL);
+    if( ret < 0 ){
+        av_log(oFmtCtx, AV_LOG_ERROR, "%s\n", av_err2str(ret));
+        goto _ERROR;
+    }
+
+    // 7.写多媒体文件头到目的文件
+
+    ret = avformat_write_header(oFmtCtx, NULL);
+    if( ret < 0 ){
+        av_log(oFmtCtx, AV_LOG_ERROR, "%s\n", av_err2str(ret));
+        goto _ERROR;
+    }
+
+
+    // cut起作用的地方
+    // 很多视频的裁剪不准确，是因为视频有IPB帧，我们很有可能裁剪到了B帧(没有I帧无法解析)，那么就必须向前或者向后来裁剪
+    // 这个函数表示，从流的哪个时间点截取文件
+    ret = av_seek_frame(pFmtCtx, -1, starttime * AV_TIME_BASE, AVSEEK_FLAG_BACKWARD);
+
+    if( ret < 0 ){
+        av_log(oFmtCtx, AV_LOG_ERROR, "%s", av_err2str(ret));
+        goto _ERROR;
+    }
+
+
+    int64_t *dts_start_time = av_calloc(pFmtCtx->nb_streams, sizeof(int64_t));
+    int64_t *pts_start_time = av_calloc(pFmtCtx->nb_streams, sizeof(int64_t));
+    for( int i = 0 ; i < pFmtCtx->nb_streams ; i++ ){
+        dts_start_time[i] = -1;
+        pts_start_time[i] = -1;
+    }
+    // 8.从源多媒体文件中读到音频/视频/字幕数据到目的文件中
+
+// 0   1   2   3   4   5 
+// -1  1  -1   1  -1   1
+
+// 0   1   2   3   4   5
+// -1  0  -1   1  -1   2
+
+    AVPacket pkt;
+    while( av_read_frame(pFmtCtx, &pkt) >= 0) {
+        AVStream *inStream, *outStream;
+
+        if( dts_start_time[pkt.stream_index] == -1 && pkt.dts > 0 ){
+            dts_start_time[pkt.stream_index] = pkt.dts;
+        }
+
+        if( pts_start_time[pkt.stream_index] == -1 && pkt.pts > 0 ){
+            pts_start_time[pkt.stream_index] = pkt.pts;
+        }
+
+        inStream = pFmtCtx->streams[pkt.stream_index];
+        if( av_q2d(inStream->time_base) * pkt.pts > endtime ){
+            av_log(oFmtCtx, AV_LOG_INFO, "success!\n");
+            break;
+        }
+
+        if( stream_map[pkt.stream_index] < 0 ){
+            av_packet_unref(&pkt);
+            continue;
+        }
+
+        pkt.pts = pkt.pts - pts_start_time[pkt.stream_index];
+        pkt.dts = pkt.dts - dts_start_time[pkt.stream_index];
+        if( pkt.pts > pkt.dts ){
+            pkt.pts = pkt.dts;
+        }  
+
+        pkt.stream_index = stream_map[pkt.stream_index];
+
+        outStream = oFmtCtx->streams[pkt.stream_index];
+        av_packet_rescale_ts(&pkt, inStream->time_base, outStream->time_base);
+        // pkt.pts = av_rescale_q_rnd(pkt.pts, inStream->time_base, outStream->time_base, (AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
+        // pkt.dts = av_rescale_q_rnd(pkt.dts, inStream->time_base, outStream->time_base, (AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
+        // pkt.duration = av_rescale_q(pkt.duration, inStream->time_base, outStream->time_base);
+        // pkt.stream_index = 0;
+        pkt.pos = -1;
+        av_interleaved_write_frame(oFmtCtx, &pkt);
+        av_packet_unref(&pkt);
+    }
+
+    // 9.写多媒体文件尾到文件中
+
+    av_write_trailer(oFmtCtx);
+
+    // 10.将申请的资源释放掉
+
+_ERROR:
+    if( pFmtCtx ){  
+        avformat_close_input(&pFmtCtx);
+        pFmtCtx = NULL;
+    }
+    if( oFmtCtx->pb ){
+        avio_close(oFmtCtx->pb);
+    }
+    if( oFmtCtx ){
+        avformat_free_context(oFmtCtx);
+        oFmtCtx = NULL;
+    }
+    if( stream_map ){
+        av_free(stream_map);
+    }
+    if( dts_start_time ){
+        av_free(dts_start_time);
+
+    }
+    if( pts_start_time ){
+        av_free(pts_start_time);
+    }
+    return 0;
+}
+