QT ubuntu下开发视频播放 FFmpeg

ubuntu 安装FFmpeg

T113VideoDemo.pro

#-------------------------------------------------
#
# Project created by QtCreator 2023-07-28T11:45:22
#
#-------------------------------------------------

QT       += core gui


greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = T113VideoDemo
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which has been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0


SOURCES += \
        main.cpp \
        mainwindow.cpp

HEADERS += \
        mainwindow.h

FORMS += \
        mainwindow.ui


INCLUDEPATH += /usr/local/ffmpeg/include \

LIBS += /usr/local/ffmpeg/lib/libavcodec.so \
        /usr/local/ffmpeg/lib/libavdevice.so \
        /usr/local/ffmpeg/lib/libavfilter.so \
        /usr/local/ffmpeg/lib/libavformat.so \
        /usr/local/ffmpeg/lib/libavutil.so \
        /usr/local/ffmpeg/lib/libpostproc.so \
        /usr/local/ffmpeg/lib/libswresample.so \
        /usr/local/ffmpeg/lib/libswscale.so \

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();
private slots:
    void slotOpenFile();

    void on_pushButton_clicked();

    void on_close_clicked();

    void on_screen_clicked();

private:
    Ui::MainWindow *ui;
    QString currentFileName;

};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QTime>
#include <QFileDialog>
#include <QScreen>
// 调用FFmpeg的头文件
extern "C"{
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libswscale/swscale.h>
#include <libavutil/imgutils.h>
}
// 延时函数
void delay(int msec){
    QTime dieTime = QTime::currentTime().addMSecs(msec);
    while( QTime::currentTime() < dieTime )
        QCoreApplication::processEvents(QEventLoop::AllEvents, 100);
}

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    this->setWindowTitle("hello");//设置窗口的标题
    QObject::connect(ui->open,SIGNAL(clicked()),this,SLOT(slotOpenFile()));

}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::slotOpenFile()//打开文件键
{
    currentFileName = QFileDialog::getOpenFileName(this, tr("open-file"), tr(""),
                                                   tr("Video files(*.rmvb *.rm *.avi *.wmv *.mkv *.asf *.3gp *.mov *.mp4 *.ogv* )"));
    if( !currentFileName.isEmpty() )
    {
        on_pushButton_clicked();
    }
}


void MainWindow::on_pushButton_clicked(){
    AVFormatContext *pFormatCtx; // 存储音视频封装格式中包含的信息
    int videoIndex = -1; // 视频帧索引，初始化为-1
    AVCodecContext *pCodecCtx; // 视频流编码结构
    AVCodec *pCodec; // 视频解码器
    AVFrame *pFrame, *pFrameRGB;
    unsigned char *out_buffer;
    AVPacket *packet;
    int ret, got_picture;
    struct SwsContext *img_convert_ctx; // 主要用于视频图像的转换

    char file_path[1280] = {0};
    strcpy(file_path,currentFileName.toUtf8().data());

    // 注册FFMpeg的库
    av_register_all();

    /*** （一）打开音视频流并获取音视频流信息 ***/
    // 初始化AVFormatContext
    pFormatCtx = avformat_alloc_context();
    // 打开音视频流
    /*avformat_open_input函数*/
    //打开一个文件并解析。可解析的内容包括：视频流、音频流、视频流参数、音频流参数、视频帧索引。
    //参数一：AVFormatContext **ps, 格式化的上下文（由avformat_alloc_context分配）的指针。
    //参数二：要打开的流的url,地址最终会存入到AVFormatContext结构体当中。
    //参数三：指定输入的封装格式。一般传NULL，由FFmpeg自行探测。
    //参数四：包含AVFormatContext和demuxer私有选项的字典。返回时，此参数将被销毁并替换为包含找不到的选项
    if (avformat_open_input(&pFormatCtx, file_path, NULL, NULL) != 0)
    {
        printf("Couldn't open input stream.\n");
        return;
    }
    // 获取音视频流数据信息
    if (avformat_find_stream_info(pFormatCtx, NULL) < 0)
    {
        printf("Couldn't find stream information.\n");
        return;
    }

    /*** （二）查找视频流位置以及查找并打开视频解码器 ***/
    // 查找视频流的起始索引位置（nb_streams表示视音频流的个数）
    for (int i = 0; i < (int)pFormatCtx->nb_streams; i++)
    {
        // 查找到视频流时退出循环
        if (pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) // 判断是否为视频流
        {
            videoIndex = i;
            break;
        }
    }
    if (videoIndex == -1)
    {
        printf("Didn't find a video stream.\n");
        return ;
    }
    // 查找视频解码器
    pCodecCtx = pFormatCtx->streams[videoIndex]->codec; // 获取视频流编码结构
    pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
    if (pCodec == NULL)
    {
        printf("Codec not found.\n");
        return ;
    }
    // 打开解码器
    if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0)
    {
        printf("Could not open codec.\n");
        return ;
    }

    // 打印视频信息
    printf("--------------- File Information ----------------\n");
    av_dump_format(pFormatCtx, 0, file_path, 0); // 此函数打印输入或输出的详细信息
    printf("-------------------------------------------------\n");

    /*** （三）视频解码的同时处理图片像素数据 ***/
    // 创建帧结构，此函数仅分配基本结构空间，图像数据空 间需通过av_malloc分配
    pFrame = av_frame_alloc();
    pFrameRGB = av_frame_alloc();
    // 创建动态内存,创建存储图像数据的空间（av_image_get_buffer_size获取一帧图像需要的大小）
    out_buffer = (unsigned char *)av_malloc((size_t)av_image_get_buffer_size(AV_PIX_FMT_RGB32, pCodecCtx->width, pCodecCtx->height, 1));
    // 存储一帧像素数据缓冲区
    av_image_fill_arrays(pFrameRGB->data, pFrameRGB->linesize, out_buffer,
                         AV_PIX_FMT_RGB32, pCodecCtx->width, pCodecCtx->height, 1);
    packet = (AVPacket *)av_malloc(sizeof(AVPacket));

    // 初始化img_convert_ctx结构
    img_convert_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height, pCodecCtx->pix_fmt,
                                     pCodecCtx->width, pCodecCtx->height, AV_PIX_FMT_RGB32, SWS_BICUBIC, NULL, NULL, NULL);
    // av_read_frame读取一帧未解码的数据
    while (av_read_frame(pFormatCtx, packet) >= 0)
    {
        // 如果是视频数据
        if (packet->stream_index == videoIndex)
        {
            // 解码一帧视频数据
            ret = avcodec_decode_video2(pCodecCtx, pFrame, &got_picture, packet);
            if (ret < 0)
            {
                printf("Decode Error.\n");
                return ;
            }
            if (got_picture)
            {
                sws_scale(img_convert_ctx, (const unsigned char* const*)pFrame->data, pFrame->linesize, 0, pCodecCtx->height,
                          pFrameRGB->data, pFrameRGB->linesize);
                QImage img((uchar*)pFrameRGB->data[0],pCodecCtx->width,pCodecCtx->height,QImage::Format_RGB32);
                ui->label->setPixmap(QPixmap::fromImage(img)); // 在label上播放视频图片
                delay(40);
            }
        }
        av_free_packet(packet);
    }

    /*** （四）最后要释放申请的内存空间 ***/
    sws_freeContext(img_convert_ctx); // 释放一个SwsContext
    av_frame_free(&pFrameRGB);
    av_frame_free(&pFrame);
    avcodec_close(pCodecCtx);
    avformat_close_input(&pFormatCtx);
}

void MainWindow::on_close_clicked(){
    close();

}

void MainWindow::on_screen_clicked(){
//    static bool max = false;
//    static QRect location = this->geometry();
//    if (max) {
//        this->setGeometry(location);
//    } else {
//        location = this->geometry();
//        this->setGeometry(qApp->desktop()->availableGeometry());
//    }

//    this->setProperty("canMove", max);
//    max = !max;

}