- FFmpeg源码编译
- Qt5使用FFmpeg
参考：Qt5 + FFmpeg
- FFmpegThread封装
- 初始化函数，只需要初始化一次即可。在最新的ffmpeg版本中，只需要初始化网络流格式。
//初始化(初始化一次即可)
void FFmpegThread::initlib() {
static QMutex mutex;
QMutexLocker locker(&mutex);
static bool isInit = false;
if (!isInit) {
//注册所有设备,主要用于本地摄像机播放支持
#ifdef ffmpegdevice
avdevice_register_all();
#endif
//初始化网络流格式,使用网络流时必须先执行
avformat_network_init();
isInit = true;
qDebug() << TIMEMS << "init ffmpeg lib ok" << " version:" << FFMPEG_VERSION;
}
}
- 设置字典参数AVDictionary *options。在FFmpeg中，av_dict_set()函数用于向字典中添加键值对。AVDictionary是FFmpeg中用于存储元数据的一种数据结构，它基本上是一个简单的哈希表，用于存储字符串类型的键值对。它可以被用来传递多种数据，例如视频解码参数、音频参数、字幕参数等等。
//设置缓存大小,1080p可将值调大
av_dict_set(&options, "buffer_size", "8192000", 0);
//以tcp方式打开,如果以udp方式打开将tcp替换为udp
av_dict_set(&options, "rtsp_transport", "tcp", 0);
//设置超时断开连接时间,单位微秒,3000000表示3秒
av_dict_set(&options, "stimeout", "3000000", 0);
// ,单位微秒,1000000表示1秒
av_dict_set(&options, "max_delay", "1000000", 0);
//自动开启线程数
av_dict_set(&options, "threads", "auto", 0);
//zerolatency:转码延迟，以牺牲视频质量减少时延
av_dict_set(&options, "tune", "zerolatency", 0);
- 打开指定的URL输入流。 打开输入流并读取标题，编解码器此时不会打开。流必须使用avformat_close_input（）关闭。
//打开视频流
avFormatContext = avformat_alloc_context();
int result = avformat_open_input(&avFormatContext, url.toStdString().data(), NULL, &options);
if (result < 0) {
qDebug() << "open input error" << url;
return false;
}
qDebug() << "open input:" << url << " " << result;
//释放设置参数
if (options != NULL) {
av_dict_free(&options);
qDebug() << "free option";
}
//获取流信息
result = avformat_find_stream_info(avFormatContext, NULL);
if (result < 0) {
qDebug() << TIMEMS << "find stream info error";
return false;
}
- 查找最佳匹配的媒体流，会返回找到的最佳匹配媒体流的索引号 。通过编解码器上下文的id查找解码器。
videoStreamIndex = av_find_best_stream(avFormatContext,
AVMEDIA_TYPE_VIDEO,
-1,
-1,
const_cast<const AVCodec **>(&videoDecoder),
0);
if (videoStreamIndex < 0) {
qDebug() << "find video stream index error";
return false;
}
//获取视频流
AVStream *videoStream = avFormatContext->streams[videoStreamIndex];
//获取视频流解码器,或者指定解码器
videoCodec = avcodec_alloc_context3(NULL);
avcodec_parameters_to_context(videoCodec, videoStream->codecpar);
videoDecoder = const_cast<AVCodec *>(avcodec_find_decoder(videoCodec->codec_id));
//videoDecoder = avcodec_find_decoder_by_name("h264_qsv");
if (videoDecoder == NULL) {
qDebug() << "video decoder not found";
return false;
}
//设置加速解码
videoCodec->lowres = videoDecoder->max_lowres;
videoCodec->flags2 |= AV_CODEC_FLAG2_FAST;
//打开视频解码器
result = avcodec_open2(videoCodec, videoDecoder, NULL);
if (result < 0) {
qDebug() << "open video codec error";
return false;
}
//获取分辨率大小
videoWidth = videoStream->codecpar->width;
videoHeight = videoStream->codecpar->height;
//如果没有获取到宽高则返回
if (videoWidth == 0 || videoHeight == 0) {
qDebug() << "find width height error";
return false;
}
QString videoInfo = QString(u8"视频流信息 -> 索引: %1 解码: %2 格式: %3 时长: %4 秒 分辨率: %5*%6")
.arg(videoStreamIndex)
.arg(videoDecoder->name, avFormatContext->iformat->name)
.arg((avFormatContext->duration) / 1000000, videoWidth, videoHeight);
qDebug() << videoInfo;
- 以类似同样的方式找到音频流解码器。
//循环查找音频流索引
audioStreamIndex = -1;
for (uint i = 0; i < avFormatContext->nb_streams; i++) {
if (avFormatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
audioStreamIndex = i;
break;
}
}
//有些没有音频流,所以这里不用返回
if (audioStreamIndex == -1) {
qDebug() << "find audio stream index error";
} else {
//获取音频流
AVStream *audioStream = avFormatContext->streams[audioStreamIndex];
audioCodec = avcodec_alloc_context3(NULL);
avcodec_parameters_to_context(audioCodec, audioStream->codecpar);
//获取音频流解码器,或者指定解码器
audioDecoder = const_cast<AVCodec *>(avcodec_find_decoder(audioCodec->codec_id));
//audioDecoder = avcodec_find_decoder_by_name("aac");
if (audioDecoder == NULL) {
qDebug() << "audio codec not found";
return false;
}
//打开音频解码器
result = avcodec_open2(audioCodec, audioDecoder, NULL);
if (result < 0) {
qDebug() << "open audio codec error";
return false;
}
QString audioInfo = QString(u8"音频流信息 -> 索引: %1 解码: %2 比特率: %3 声道数: %4 采样: %5")
.arg(audioStreamIndex)
.arg(audioDecoder->name)
.arg(avFormatContext->bit_rate, audioCodec->channels, audioCodec->sample_rate);
qDebug() << audioInfo;
}
- 分配AVPacket内存并将其字段设置为默认值。由此产生的struct必须使用av_packet_free()释放。然后进行图像的转换。
//预分配好内存
avPacket = av_packet_alloc();
avFrame = av_frame_alloc();
avFrame2 = av_frame_alloc();
avFrame3 = av_frame_alloc();
//比较上一次文件的宽度高度,当改变时,需要重新分配内存
if (oldWidth != videoWidth || oldHeight != videoHeight) {
int byte = av_image_get_buffer_size(AV_PIX_FMT_RGB32, videoWidth, videoHeight, 1);
buffer = (uint8_t *) av_malloc(byte * sizeof(uint8_t));
oldWidth = videoWidth;
oldHeight = videoHeight;
}
//定义像素格式
AVPixelFormat srcFormat = AV_PIX_FMT_YUV420P;
AVPixelFormat dstFormat = AV_PIX_FMT_RGB32;
//通过解码器获取解码格式
srcFormat = videoCodec->pix_fmt;
//默认最快速度的解码采用的SWS_FAST_BILINEAR参数,可能会丢失部分图片数据,可以自行更改成其他参数
int flags = SWS_FAST_BILINEAR;
//开辟缓存存储一帧数据
//以下两种方法都可以,avpicture_fill已经逐渐被废弃
//avpicture_fill((AVPicture *)avFrame3, buffer, dstFormat, videoWidth, videoHeight);
av_image_fill_arrays(avFrame3->data, avFrame3->linesize, buffer,
dstFormat, videoWidth, videoHeight, 1);
//图像转换
swsContext = sws_getContext(videoWidth, videoHeight, srcFormat,
videoWidth, videoHeight, dstFormat,
flags, NULL, NULL, NULL);
- 子线程循环对帧数据处理，判断当前处理的包时视频还是音频（此案例只处理视频数据）。如果是视频数据，则将其转化为图像QImage,在通过本次解析出来的时间戳减去上一帧的时间戳得到需要延时的时间间隔。
void FFmpegThread::run() {
// qint64 startTime = av_gettime();
while (!stopped) {
//根据标志位执行初始化操作
if (isPlay) {
bool ret = this->init();
if (!ret) {
emit signal_initFailed();
stopped = !stopped;
break;
}
isPlay = false;
continue;
}
frameFinish = av_read_frame(avFormatContext, avPacket);
if (frameFinish >= 0) {
//判断当前包是视频还是音频
int index = avPacket->stream_index;
if (index == videoStreamIndex) {
frameFinish = avcodec_send_packet(videoCodec, avPacket);
if (frameFinish < 0) {
continue;
}
frameFinish = avcodec_receive_frame(videoCodec, avFrame2);
if (frameFinish < 0) {
continue;
}
if (frameFinish >= 0) {
//将数据转成一张图片
sws_scale(swsContext, (const uint8_t *const *) avFrame2->data, avFrame2->linesize, 0,
videoHeight, avFrame3->data, avFrame3->linesize);
//以下两种方法都可以
//QImage image(avFrame3->data[0], videoWidth, videoHeight, QImage::Format_RGB32);
QImage image((uchar *) buffer, videoWidth, videoHeight, QImage::Format_RGB32);
if (!image.isNull()) {
emit signal_receiveImage(image);
}
usleep(1);
}
#if 0
//延时(不然文件会立即全部播放完)
AVRational timeBase = {1, AV_TIME_BASE};
int64_t ptsTime = av_rescale_q(avPacket->dts, avFormatContext->streams[videoStreamIndex]->time_base, timeBase);
// 微秒
int64_t nowTime = av_gettime() - startTime;
qDebug() << "ptstime:" << ptsTime << "nowTime:" << nowTime;
if (ptsTime > nowTime) {
av_usleep(ptsTime - nowTime);
}
#else
AVRational timeBase = {1, AV_TIME_BASE};
int64_t ptsTime = av_rescale_q(avPacket->dts,
avFormatContext->streams[videoStreamIndex]->time_base,
timeBase);
currentTime = ptsTime;
if (lastTime == 0) {
av_usleep(10 * 1000);
}
if ((currentTime - lastTime) > 1 * 1000 * 1000 || (currentTime - lastTime) < 0) {
av_usleep(10 * 1000);
} else {
av_usleep(currentTime - lastTime);
}
lastTime = currentTime;
#endif
} else if (index == audioStreamIndex) {
//解码音频流,自行处理
}
}
av_packet_unref(avPacket);
av_freep(avPacket);
usleep(1);
}
//线程结束后释放资源
free();
stopped = false;
isPlay = false;
qDebug() << "stop ffmpeg thread";
emit signal_threadOver();
}
- FFmpegWidget封装
- 构造函数，实例化FFmpeg子线程，处理子线程中处理完图像的型号，以及初始化失败的信号。
FFmpegWidget::FFmpegWidget(QWidget *parent) : QWidget(parent) {
thread = new FFmpegThread(this);
connect(thread, SIGNAL(signal_receiveImage(QImage)), this, SLOT(updateImage(QImage)));
image = QImage();
connect(thread, &FFmpegThread::signal_initFailed, this, &FFmpegWidget::signal_openVideoFailed);
}
void FFmpegWidget::updateImage(const QImage &image) {
this->image = image;
this->update();
}
- 重写paintEvent，将从FFmpeg子线程中接收到的图像数据绘制在QWidget窗口中。
void FFmpegWidget::paintEvent(QPaintEvent *) {
if (image.isNull()) {
return;
}
QPainter painter(this);
#if 0
//image = image.scaled(this->size(), Qt::KeepAspectRatio);
//按照比例自动居中绘制
int pixX = rect().center().x() - image.width() / 2;
int pixY = rect().center().y() - image.height() / 2;
QPoint point(pixX, pixY);
painter.drawImage(point, image);
#else
painter.drawImage(this->rect(), image);
#endif
}
- 启动/停止视频。通过控制FFmpeg子线程中的循环标志来控制视频播放。
void FFmpegWidget::open() {
qDebug() << TIMEMS << "open video" << objectName();
clear();
thread->play();
thread->start();
}
void FFmpegWidget::close() {
qDebug() << TIMEMS << "close video" << objectName();
if (thread->isRunning()) {
thread->stop();
thread->quit();
thread->wait(500);
}
QTimer::singleShot(1, this, SLOT(clear()));
}
- Qt调用
在QT中只需要在ui文件中添加一个QWidget，并将这个QWidget部件提升为FFmpegWidget即可，通过调用FFmpegWidget的setUrl()方法设置拉流地址，然后通过open()和close()方法启动和停止视频。
- 源代码
- ffmpeginclude.h
#ifndef FFMPEGINCLUDE_H
#define FFMPEGINCLUDE_H
//为了兼容C和C99标准必须加以下内容(否则编译不能通过)
#ifndef INT64_C
#define INT64_C
#define UINT64_C
#endif
//引入ffmpeg头文件
extern "C" {
#include "libavutil/opt.h"
#include "libavutil/time.h"
#include "libavutil/frame.h"
#include "libavutil/display.h"
#include "libavutil/pixdesc.h"
#include "libavutil/avassert.h"
#include "libavutil/imgutils.h"
#include "libavutil/ffversion.h"
#include "libavcodec/avcodec.h"
#include "libswscale/swscale.h"
#include "libswresample/swresample.h"
#include "libavformat/avformat.h"
#include "libavfilter/avfilter.h"
#include "libavfilter/buffersink.h"
#include "libavfilter/buffersrc.h"
#include "libavdevice/avdevice.h"
#if (LIBAVCODEC_VERSION_MAJOR > 56)
#include "libavutil/hwcontext.h"
#endif
}
#include <QObject>
#include <QDateTime>
#include <QDebug>
#ifdef Q_CC_MSVC
#pragma execution_character_set("utf-8")
#endif
#ifndef TIMEMS
#define TIMEMS qPrintable(QTime::currentTime().toString("HH:mm:ss") + "[" + __FUNCTION__ + ":" + QString::number(__LINE__ ) + "]")
#endif
//通过avcode版本定义对应主版本
#if (LIBAVCODEC_VERSION_MAJOR == 56)
#define FFMPEG_VERSION_MAJOR 2
#elif (LIBAVCODEC_VERSION_MAJOR == 57)
#define FFMPEG_VERSION_MAJOR 3
#elif (LIBAVCODEC_VERSION_MAJOR == 58)
#define FFMPEG_VERSION_MAJOR 4
#elif (LIBAVCODEC_VERSION_MAJOR == 59)
#define FFMPEG_VERSION_MAJOR 5
#elif (LIBAVCODEC_VERSION_MAJOR == 60)
#define FFMPEG_VERSION_MAJOR 6
#endif
#if (FFMPEG_VERSION_MAJOR > 4)
#define AVCodecx const AVCodec
#define AVInputFormatx const AVInputFormat
#define AVOutputFormatx const AVOutputFormat
#else
#define AVCodecx AVCodec
#define AVInputFormatx AVInputFormat
#define AVOutputFormatx AVOutputFormat
#endif
#if (FFMPEG_VERSION_MAJOR < 3)
enum AVHWDeviceType {
AV_HWDEVICE_TYPE_VDPAU,
AV_HWDEVICE_TYPE_CUDA,
AV_HWDEVICE_TYPE_VAAPI,
AV_HWDEVICE_TYPE_DXVA2,
AV_HWDEVICE_TYPE_QSV,
AV_HWDEVICE_TYPE_VIDEOTOOLBOX,
AV_HWDEVICE_TYPE_NONE,
AV_HWDEVICE_TYPE_D3D11VA,
AV_HWDEVICE_TYPE_DRM,
};
#endif
#endif // FFMPEGINCLUDE_H
- ffmpeg.h
#ifndef FFMPEG_H
#define FFMPEG_H
#include <QtGui>
#include <QWidget>
#include "ffmpeginclude.h"
class FFmpegThread : public QThread
{
Q_OBJECT
public:
explicit FFmpegThread(QObject *parent = 0);
/// 初始化
static void initlib();
protected:
void run();
private:
/// 线程停止标志位
volatile bool stopped = false;
/// 播放视频标志位
volatile bool isPlay = false;
/// 一帧完成
int frameFinish = 0;
/// 视频宽度
int videoWidth = 0;
/// 视频高度
int videoHeight = 0;
/// 上一次视频宽度
int oldWidth = 0;
/// 上一次视频高度
int oldHeight = 0;
/// 视频流索引
int videoStreamIndex = -1;
/// 音频流索引
int audioStreamIndex = -1;
/// 视频流地址
QString url = "";
/// 存储解码后图片buffer
uint8_t *buffer;
/// 包对象
AVPacket *avPacket;
/// 帧对象
AVFrame *avFrame;
/// 帧对象
AVFrame *avFrame2;
/// 帧对象
AVFrame *avFrame3;
/// 格式对象
AVFormatContext *avFormatContext;
/// 视频解码器
AVCodecContext *videoCodec;
/// 音频解码器
AVCodecContext *audioCodec;
/// 处理图片数据对象
SwsContext *swsContext;
/// 参数对象
AVDictionary *options;
/// 视频解码
AVCodec *videoDecoder;
/// 音频解码
AVCodec *audioDecoder;
/// 记录上一次时间戳
qint64 lastTime = 0;
/// 记录当前时间戳
qint64 currentTime = 0;
signals:
/// 信号：收到图片信号
void signal_receiveImage(const QImage &image);
/// 信号：初始化失败
void signal_initFailed();
/// 信号：线程结束
void signal_threadOver();
public slots:
/// 设置视频流地址
void setUrl(const QString &url);
/// 初始化视频对象
bool init();
/// 释放对象
void free();
/// 播放视频对象
void play();
/// 暂停播放
void pause();
/// 继续播放
void next();
/// 停止采集线程
void stop();
};
//实时视频显示窗体类
class FFmpegWidget : public QWidget
{
Q_OBJECT
public:
explicit FFmpegWidget(QWidget *parent = 0);
~FFmpegWidget();
protected:
void paintEvent(QPaintEvent *);
private:
FFmpegThread *thread;
QImage image;
signals:
/// 信号：打开视频失败
void signal_openVideoFailed();
private slots:
/// 接收图像并绘制
void updateImage(const QImage &image);
public slots:
/// 设置视频流地址
void setUrl(const QString &url);
/// 打开设备
void open();
/// 暂停
void pause();
/// 继续
void next();
/// 关闭设备
void close();
///清空
void clear();
};
#endif // FFMPEG_H
- ffmpeg.cpp
#include "ffmpeg.h"
FFmpegThread::FFmpegThread(QObject *parent) : QThread(parent) {
setObjectName("FFmpegThread");
buffer = NULL;
avPacket = NULL;
avFrame = NULL;
avFrame2 = NULL;
avFrame3 = NULL;
avFormatContext = NULL;
videoCodec = NULL;
audioCodec = NULL;
swsContext = NULL;
options = NULL;
videoDecoder = NULL;
audioDecoder = NULL;
//初始化注册(注册一次即可)
FFmpegThread::initlib();
}
//初始化(初始化一次即可)
void FFmpegThread::initlib() {
static QMutex mutex;
QMutexLocker locker(&mutex);
static bool isInit = false;
if (!isInit) {
//注册所有设备,主要用于本地摄像机播放支持
#ifdef ffmpegdevice
avdevice_register_all();
#endif
//初始化网络流格式,使用网络流时必须先执行
avformat_network_init();
isInit = true;
qDebug() << TIMEMS << "init ffmpeg lib ok" << " version:" << FFMPEG_VERSION;
}
}
bool FFmpegThread::init() {
//在打开码流前指定各种参数比如:探测时间/超时时间/最大延时等
//设置缓存大小,1080p可将值调大
av_dict_set(&options, "buffer_size", "8192000", 0);
//以tcp方式打开,如果以udp方式打开将tcp替换为udp
av_dict_set(&options, "rtsp_transport", "tcp", 0);
//设置超时断开连接时间,单位微秒,3000000表示3秒
av_dict_set(&options, "stimeout", "3000000", 0);
// ,单位微秒,1000000表示1秒
av_dict_set(&options, "max_delay", "1000000", 0);
//自动开启线程数
av_dict_set(&options, "threads", "auto", 0);
//zerolatency:转码延迟，以牺牲视频质量减少时延
av_dict_set(&options, "tune", "zerolatency", 0);
//打开视频流
avFormatContext = avformat_alloc_context();
int result = avformat_open_input(&avFormatContext, url.toStdString().data(), NULL, &options);
if (result < 0) {
qDebug() << TIMEMS << "open input error" << url;
return false;
}
qDebug() << TIMEMS << "open input:" << url << " " << result;
//释放设置参数
if (options != NULL) {
av_dict_free(&options);
qDebug() << TIMEMS << "free option";
}
//获取流信息
result = avformat_find_stream_info(avFormatContext, NULL);
if (result < 0) {
qDebug() << TIMEMS << "find stream info error";
return false;
}
//----------视频流部分开始,打个标记方便折叠代码----------
if (1) {
videoStreamIndex = av_find_best_stream(avFormatContext,
AVMEDIA_TYPE_VIDEO,
-1,
-1,
const_cast<const AVCodec **>(&videoDecoder),
0);
if (videoStreamIndex < 0) {
qDebug() << TIMEMS << "find video stream index error";
return false;
}
//获取视频流
AVStream *videoStream = avFormatContext->streams[videoStreamIndex];
//获取视频流解码器,或者指定解码器
videoCodec = avcodec_alloc_context3(NULL);
avcodec_parameters_to_context(videoCodec, videoStream->codecpar);
videoDecoder = const_cast<AVCodec *>(avcodec_find_decoder(videoCodec->codec_id));
//videoDecoder = avcodec_find_decoder_by_name("h264_qsv");
if (videoDecoder == NULL) {
qDebug() << TIMEMS << "video decoder not found";
return false;
}
//设置加速解码
videoCodec->lowres = videoDecoder->max_lowres;
videoCodec->flags2 |= AV_CODEC_FLAG2_FAST;
//打开视频解码器
result = avcodec_open2(videoCodec, videoDecoder, NULL);
if (result < 0) {
qDebug() << TIMEMS << "open video codec error";
return false;
}
//获取分辨率大小
videoWidth = videoStream->codecpar->width;
videoHeight = videoStream->codecpar->height;
//如果没有获取到宽高则返回
if (videoWidth == 0 || videoHeight == 0) {
qDebug() << TIMEMS << "find width height error";
return false;
}
QString videoInfo = QString(u8"视频流信息 -> 索引: %1 解码: %2 格式: %3 时长: %4 秒 分辨率: %5*%6")
.arg(videoStreamIndex)
.arg(videoDecoder->name, avFormatContext->iformat->name)
.arg((avFormatContext->duration) / 1000000, videoWidth, videoHeight);
qDebug() << TIMEMS << videoInfo;
}
//----------视频流部分开始----------
//----------音频流部分开始,打个标记方便折叠代码----------
if (1) {
//循环查找音频流索引
audioStreamIndex = -1;
for (uint i = 0; i < avFormatContext->nb_streams; i++) {
if (avFormatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
audioStreamIndex = i;
break;
}
}
//有些没有音频流,所以这里不用返回
if (audioStreamIndex == -1) {
qDebug() << TIMEMS << "find audio stream index error";
} else {
//获取音频流
AVStream *audioStream = avFormatContext->streams[audioStreamIndex];
audioCodec = avcodec_alloc_context3(NULL);
avcodec_parameters_to_context(audioCodec, audioStream->codecpar);
//获取音频流解码器,或者指定解码器
audioDecoder = const_cast<AVCodec *>(avcodec_find_decoder(audioCodec->codec_id));
//audioDecoder = avcodec_find_decoder_by_name("aac");
if (audioDecoder == NULL) {
qDebug() << TIMEMS << "audio codec not found";
return false;
}
//打开音频解码器
result = avcodec_open2(audioCodec, audioDecoder, NULL);
if (result < 0) {
qDebug() << TIMEMS << "open audio codec error";
return false;
}
QString audioInfo = QString(u8"音频流信息 -> 索引: %1 解码: %2 比特率: %3 声道数: %4 采样: %5")
.arg(audioStreamIndex)
.arg(audioDecoder->name)
.arg(avFormatContext->bit_rate, audioCodec->channels, audioCodec->sample_rate);
qDebug() << TIMEMS << audioInfo;
}
}
//----------音频流部分结束----------
//预分配好内存
avPacket = av_packet_alloc();
avFrame = av_frame_alloc();
avFrame2 = av_frame_alloc();
avFrame3 = av_frame_alloc();
//比较上一次文件的宽度高度,当改变时,需要重新分配内存
if (oldWidth != videoWidth || oldHeight != videoHeight) {
int byte = av_image_get_buffer_size(AV_PIX_FMT_RGB32, videoWidth, videoHeight, 1);
buffer = (uint8_t *) av_malloc(byte * sizeof(uint8_t));
oldWidth = videoWidth;
oldHeight = videoHeight;
}
//定义像素格式
AVPixelFormat srcFormat = AV_PIX_FMT_YUV420P;
AVPixelFormat dstFormat = AV_PIX_FMT_RGB32;
//通过解码器获取解码格式
srcFormat = videoCodec->pix_fmt;
//默认最快速度的解码采用的SWS_FAST_BILINEAR参数,可能会丢失部分图片数据,可以自行更改成其他参数
int flags = SWS_FAST_BILINEAR;
//开辟缓存存储一帧数据
//以下两种方法都可以,avpicture_fill已经逐渐被废弃
//avpicture_fill((AVPicture *)avFrame3, buffer, dstFormat, videoWidth, videoHeight);
av_image_fill_arrays(avFrame3->data, avFrame3->linesize, buffer,
dstFormat, videoWidth, videoHeight, 1);
//图像转换
swsContext = sws_getContext(videoWidth, videoHeight, srcFormat,
videoWidth, videoHeight, dstFormat,
flags, NULL, NULL, NULL);
//输出视频信息
//av_dump_format(avFormatContext, 0, url.toStdString().data(), 0);
qDebug() << TIMEMS << "init ffmpeg finsh";
return true;
}
void FFmpegThread::run() {
// qint64 startTime = av_gettime();
while (!stopped) {
//根据标志位执行初始化操作
if (isPlay) {
bool ret = this->init();
if (!ret) {
emit signal_initFailed();
stopped = !stopped;
break;
}
isPlay = false;
continue;
}
frameFinish = av_read_frame(avFormatContext, avPacket);
if (frameFinish >= 0) {
//判断当前包是视频还是音频
int index = avPacket->stream_index;
if (index == videoStreamIndex) {
frameFinish = avcodec_send_packet(videoCodec, avPacket);
if (frameFinish < 0) {
continue;
}
frameFinish = avcodec_receive_frame(videoCodec, avFrame2);
if (frameFinish < 0) {
continue;
}
if (frameFinish >= 0) {
//将数据转成一张图片
sws_scale(swsContext, (const uint8_t *const *) avFrame2->data, avFrame2->linesize, 0,
videoHeight, avFrame3->data, avFrame3->linesize);
//以下两种方法都可以
//QImage image(avFrame3->data[0], videoWidth, videoHeight, QImage::Format_RGB32);
QImage image((uchar *) buffer, videoWidth, videoHeight, QImage::Format_RGB32);
if (!image.isNull()) {
emit signal_receiveImage(image);
}
usleep(1);
}
#if 0
//延时(不然文件会立即全部播放完)
AVRational timeBase = {1, AV_TIME_BASE};
int64_t ptsTime = av_rescale_q(avPacket->dts, avFormatContext->streams[videoStreamIndex]->time_base, timeBase);
// 微秒
int64_t nowTime = av_gettime() - startTime;
qDebug() << "ptstime:" << ptsTime << "nowTime:" << nowTime;
if (ptsTime > nowTime) {
av_usleep(ptsTime - nowTime);
}
#else
AVRational timeBase = {1, AV_TIME_BASE};
int64_t ptsTime = av_rescale_q(avPacket->dts,
avFormatContext->streams[videoStreamIndex]->time_base,
timeBase);
currentTime = ptsTime;
if (lastTime == 0) {
av_usleep(10 * 1000);
}
if ((currentTime - lastTime) > 1 * 1000 * 1000 || (currentTime - lastTime) < 0) {
av_usleep(10 * 1000);
} else {
av_usleep(currentTime - lastTime);
}
lastTime = currentTime;
#endif
} else if (index == audioStreamIndex) {
//解码音频流,自行处理
}
}
av_packet_unref(avPacket);
av_freep(avPacket);
usleep(1);
}
//线程结束后释放资源
free();
stopped = false;
isPlay = false;
qDebug() << TIMEMS << "stop ffmpeg thread";
emit signal_threadOver();
}
void FFmpegThread::setUrl(const QString &url) {
this->url = url;
}
void FFmpegThread::free() {
if (swsContext != NULL) {
sws_freeContext(swsContext);
swsContext = NULL;
}
if (avPacket != NULL) {
av_packet_unref(avPacket);
avPacket = NULL;
}
if (avFrame != NULL) {
av_frame_free(&avFrame);
avFrame = NULL;
}
if (avFrame2 != NULL) {
av_frame_free(&avFrame2);
avFrame2 = NULL;
}
if (avFrame3 != NULL) {
av_frame_free(&avFrame3);
avFrame3 = NULL;
}
if (videoCodec != NULL) {
avcodec_close(videoCodec);
videoCodec = NULL;
}
if (audioCodec != NULL) {
avcodec_close(audioCodec);
audioCodec = NULL;
}
if (avFormatContext != NULL) {
avformat_close_input(&avFormatContext);
avFormatContext = NULL;
}
av_dict_free(&options);
qDebug() << TIMEMS << "close ffmpeg ok";
}
void FFmpegThread::play() {
//通过标志位让线程执行初始化
isPlay = true;
}
void FFmpegThread::pause() {
}
void FFmpegThread::next() {
}
void FFmpegThread::stop() {
//通过标志位让线程停止
stopped = true;
}
//实时视频显示窗体类
FFmpegWidget::FFmpegWidget(QWidget *parent) : QWidget(parent) {
thread = new FFmpegThread(this);
connect(thread, SIGNAL(signal_receiveImage(QImage)), this, SLOT(updateImage(QImage)));
image = QImage();
connect(thread, &FFmpegThread::signal_initFailed, this, &FFmpegWidget::signal_openVideoFailed);
}
FFmpegWidget::~FFmpegWidget() {
close();
}
void FFmpegWidget::paintEvent(QPaintEvent *) {
if (image.isNull()) {
return;
}
QPainter painter(this);
#if 0
//image = image.scaled(this->size(), Qt::KeepAspectRatio);
//按照比例自动居中绘制
int pixX = rect().center().x() - image.width() / 2;
int pixY = rect().center().y() - image.height() / 2;
QPoint point(pixX, pixY);
painter.drawImage(point, image);
#else
painter.drawImage(this->rect(), image);
#endif
}
void FFmpegWidget::updateImage(const QImage &image) {
this->image = image;
this->update();
}
void FFmpegWidget::setUrl(const QString &url) {
thread->setUrl(url);
}
void FFmpegWidget::open() {
qDebug() << TIMEMS << "open video" << objectName();
clear();
thread->play();
thread->start();
}
void FFmpegWidget::pause() {
thread->pause();
}
void FFmpegWidget::next() {
thread->next();
}
void FFmpegWidget::close() {
qDebug() << TIMEMS << "close video" << objectName();
if (thread->isRunning()) {
thread->stop();
thread->quit();
thread->wait(500);
}
QTimer::singleShot(1, this, SLOT(clear()));
}
void FFmpegWidget::clear() {
image = QImage();
update();
}
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