C++ OpenCV 3.4 / FFMPEG 3.4.1 VideoWriter 和 MP4 输出文件格式

Question

我正在运行一个带有Linux Kernel 4.9.35-ti-r44的ARM BeagleBone X-15 Debian机器。在我的C++(Qt 5)应用程序中，我想将我的cv::Mat帧保存为MP4格式的视频。我已经安装了libx264，并从头编译了ffmpeg和OpenCv。我可以成功地使用AVI视频容器类型记录和查看MJPEG视频，但不能使用MP4。每当我尝试写入MP4视频时，我会收到如下的运行时错误：

OpenCV: FFMPEG: tag 0x44495658/'XVID' is not supported with codec id 13 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x00000020/' ???'

我尝试过各种谷歌答案，但都没有奏效。

相关代码：

cv::Size frameSize = frame.size();

qDebug() << "Initializing Video Recording to save Video file here: " << destinationFileName;

std::string filename = destinationFileName.toStdString();
//int fcc =   CV_FOURCC('M','J','P','G');
//int fcc =   CV_FOURCC('X','2','6','4');
int fcc = CV_FOURCC('X','V','I','D');
int fps =   1;
videoRecorder = new cv::VideoWriter(filename,fcc,fps,frameSize);

...

videoRecorder->write(frame);

我已经下载并构建了最新的OpenCV 3.4，但问题仍然存在。如何使用OpenCV的视频写入器将内容写入MP4文件？

当我尝试使用“X”、“2”、“6”、“4”格式时，会出现以下错误：

    Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
OpenCV: FFMPEG: tag 0x34363258/'X264' is not supported with codec id 28 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x31637661/'avc1'
[h264_v4l2m2m @ 0x81042020] Could not find a valid device
[h264_v4l2m2m @ 0x81042020] can't configure encoder
Could not open codec 'h264_v4l2m2m': Unspecified error
Starting

当我尝试使用“X”，“V”，“I”，“D”格式时，出现错误：

Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
OpenCV: FFMPEG: tag 0x44495658/'XVID' is not supported with codec id 13 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x7634706d/'mp4v'
Starting

当我尝试使用'M'、'P'、'E'和'MPEG'格式时，会出现以下错误：

Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
OpenCV: FFMPEG: tag 0x4745504d/'MPEG' is not supported with codec id 2 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x7634706d/'mp4v'
Starting

尝试使用“H”，“2”，“6”，“4”格式时，我收到了错误提示：

OpenCV: FFMPEG: tag 0x34363248/'H264' is not supported with codec id 28 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x31637661/'avc1'
[h264_v4l2m2m @ 0x7fdde340] Could not find a valid device
[h264_v4l2m2m @ 0x7fdde340] can't configure encoder
Could not open codec 'h264_v4l2m2m': Unspecified error
Starting

当我尝试使用'M'、'P'、'4'、'V'格式时，出现错误：

Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
OpenCV: FFMPEG: tag 0x5634504d/'MP4V' is not supported with codec id 13 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x7634706d/'mp4v'
Starting

当我尝试使用“A”、“V”、“C”、“1”格式时，会出现错误：

Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
OpenCV: FFMPEG: tag 0x31435641/'AVC1' is not supported with codec id 28 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x31637661/'avc1'
[h264_v4l2m2m @ 0x810f5f50] Could not find a valid device
[h264_v4l2m2m @ 0x810f5f50] can't configure encoder
Could not open codec 'h264_v4l2m2m': Unspecified error
Starting

当我尝试使用“D”，“I”，“V”，“X”格式时，出现错误：

Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
OpenCV: FFMPEG: tag 0x58564944/'DIVX' is not supported with codec id 13 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x7634706d/'mp4v'
Starting

当我尝试使用0x21格式时，会出现错误：

Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
OpenCV: FFMPEG: tag 0x00000021/'!???' is not found (format 'mp4 / MP4 (MPEG-4 Part 14)')'
Starting

这是我完整的类，展示了所有尝试过的格式:

    #include "downloader.h"

Downloader::Downloader(QString url, QString destinationFile) : downloadUrl(url) , destinationFileName(destinationFile)
{

    didInitializeVideoWriter = false;

    qDebug() << "Initialized Downloader...";

}

Downloader::~Downloader() {

    videoRecorder->release();
    delete videoRecorder;

}

void Downloader::doDownload()
{
    networkManager = new QNetworkAccessManager(this);

    connect(networkManager, SIGNAL(finished(QNetworkReply*)),
            this, SLOT(replyFinished(QNetworkReply*)));

    networkManager->get(QNetworkRequest(QUrl(downloadUrl)));
}

void Downloader::writeFrame(cv::Mat frame) {

    QMutexLocker locker(&videoFrameMutex);

    videoRecorder->write(frame);

}

void Downloader::replyFinished(QNetworkReply *reply)
{

    if(reply->error())
    {
        qDebug() << "ERROR!";
        qDebug() << reply->errorString();
    }
    else
    {
        //qDebug() << reply->header(QNetworkRequest::ContentTypeHeader).toString();
        //qDebug() << reply->header(QNetworkRequest::LastModifiedHeader).toDateTime().toString();
        //qDebug() << reply->header(QNetworkRequest::ContentLengthHeader).toULongLong();
        qDebug() << reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
        qDebug() << reply->attribute(QNetworkRequest::HttpReasonPhraseAttribute).toString();

        QString tempFileName = destinationFileName;
        QString jpegTempFilename = QString("%1").arg(tempFileName.replace("mp4","jpeg"));

        qDebug() << "Overwriting: " << jpegTempFilename;
        QFile *file = new QFile(jpegTempFilename);
        if(file->open(QFile::WriteOnly))
        {
            file->write(reply->readAll());
            file->flush();
            file->close();
        }
        delete file;

        cv::Mat frame = imread(jpegTempFilename.toStdString(), CV_LOAD_IMAGE_COLOR);   // CV_LOAD_IMAGE_COLOR (>0) loads the image in the BGR format
        cv::cvtColor(frame,frame,CV_BGR2RGB);

        // Now lazy load the recorder
        if ( !didInitializeVideoWriter ) {

            cv::Size frameSize = frame.size();

            qDebug() << "Initializing Video Recording to save Video file here: " << destinationFileName;

            std::string filename = destinationFileName.toStdString();
            //int fcc =   CV_FOURCC('M','J','P','G');
            int fcc =   CV_FOURCC('X','2','6','4');
            //int fcc = CV_FOURCC('X','V','I','D');
            //int fcc = CV_FOURCC('M','P','E','G');
            //int fcc = CV_FOURCC('H','2','6','4');
            //int fcc = CV_FOURCC('M','P','4','V');
            //int fcc = CV_FOURCC('A','V','C','1');
            //int fcc = CV_FOURCC('D','I','V','X');
            //int fcc = 0x21;
            //int fcc = 0x00000021;
            int fps =   1;
            videoRecorder = new cv::VideoWriter(filename,fcc,fps,frameSize);

            qDebug() << "Starting";
            frameCounter = 1;
            performanceTimer.start();

            didInitializeVideoWriter = true;

        }

        cv::putText(frame,"[REC]",cv::Point(50,50),5,1,cv::Scalar(0,0,225));

        QFuture<void> backgroundRun = QtConcurrent::run(this, &Downloader::writeFrame, frame);
        //backgroundRun.waitForFinished();

    }

    reply->deleteLater();

    qDebug() << "RequestTimer: " << performanceTimer.elapsed() << frameCounter;

    // Requests Again
    networkManager->get(QNetworkRequest(QUrl(downloadUrl)));

    frameCounter++;

    performanceTimer.restart();


}

更新 - 我尝试了'a'、'v'、'c'、'1'，但很遗憾这些也不起作用：

Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
[h264_v4l2m2m @ 0x810f6aa0] Could not find a valid device
[h264_v4l2m2m @ 0x810f6aa0] can't configure encoder
Could not open codec 'h264_v4l2m2m': Unspecified error

(qt-downloader:6234): GStreamer-CRITICAL **: gst_element_make_from_uri: assertion 'gst_uri_is_valid (uri)' failed
OpenCV Error: Unspecified error (GStreamer: cannot link elements
) in CvVideoWriter_GStreamer::open, file /media/usb/opencv/modules/videoio/src/cap_gstreamer.cpp, line 1635
VIDEOIO(cvCreateVideoWriter_GStreamer (filename, fourcc, fps, frameSize, is_color)): raised OpenCV exception:

/media/usb/opencv/modules/videoio/src/cap_gstreamer.cpp:1635: error: (-2) GStreamer: cannot link elements
 in function CvVideoWriter_GStreamer::open

当我尝试使用X264 FOURCC时，MP4文件大小为48字节，但是从未增长：

Initializing Video Recording to save Video file here:  "/tmp/Garage.mp4"
OpenCV: FFMPEG: tag 0x34363258/'X264' is not supported with codec id 27 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x31637661/'avc1'

静态大小：

debian@BeagleBoard-X15:/tmp$ ls -lrt Garage.*
-rw-r--r-- 1 debian debian     48 Dec 24 21:13 Garage.mp4
-rw-r--r-- 1 debian debian 100424 Dec 24 21:14 Garage.jpeg
debian@BeagleBoard-X15:/tmp$ hexdump Garage.mp4 
0000000 0000 2000 7466 7079 7369 6d6f 0000 0002
0000010 7369 6d6f 7369 326f 7661 3163 706d 3134
0000020 0000 0800 7266 6565 0000 0000 646d 7461
0000030

以下是我的ffmpeg构建配置：

debian@BeagleBoard-X15:/tmp$ ffmpeg -buildconf
ffmpeg version N-89524-g74f408cc8e Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 6.3.0 (Debian 6.3.0-18) 20170516
  configuration: --enable-gpl --enable-libx264 --enable-pthreads --enable-static --extra-cflags=-I./x264/include --extra-ldflags=-L./x264/lib --extra-libs=-ldl
  libavutil      56.  6.100 / 56.  6.100
  libavcodec     58.  8.100 / 58.  8.100
  libavformat    58.  3.100 / 58.  3.100
  libavdevice    58.  0.100 / 58.  0.100
  libavfilter     7.  7.100 /  7.  7.100
  libswscale      5.  0.101 /  5.  0.101
  libswresample   3.  0.101 /  3.  0.101
  libpostproc    55.  0.100 / 55.  0.100

  configuration:
    --enable-gpl
    --enable-libx264
    --enable-pthreads
    --enable-static
    --extra-cflags=-I./x264/include
    --extra-ldflags=-L./x264/lib
    --extra-libs=-ldl

- PhilBot

---

感谢您的评论 - 我已确保安装了libxvid。我的make pro文件包括libx264和libxvidecore（LIBS + = -lx264 LIBS + = -lxvidcore）。然而，我仍然看到问题。 - PhilBot

我从apt-get安装了它们，之前也从apt-get安装了ffmpeg - 所以也许我的ffmpeg没有支持！我会尝试编译它。 - PhilBot

我还建议在没有使用OpenCV的情况下测试FFmpeg（使用命令行FFmpeg）以定位问题。 - Dmitrii Z.

请参见 https://dev59.com/F1sX5IYBdhLWcg3wRdt_ - Gyan

@Mulvya - 我尝试了avc1，但不幸的是我遇到了同样的问题。请查看我的修订帖子。 - PhilBot

Answer 1

我在MacOS上遇到了类似的问题，但我通过重新安装最新版本的X264库并使用./configure --enable-libx264 --enable-gpl --enable-avresample --enable-shared重新安装FFMPEG来正确地将新的X264链接到FFMPEG。然后重新安装OpenCV（我使用的是3.4.4版本）以链接新的FFMPEG。在构建OpenCV时，请确保WITH FFMPEG为ON，否则将使用内置的OpenCV编码器，这将给您更有限的选项。

- Kevin

Answer 2

你尝试过像这样使用纯 C++11 吗：

    using namespace std;
    using namespace cv;

int main(){

    // Create a VideoCapture object and use camera to capture the video
    VideoCapture cap(0);

    // Check if camera opened successfully
    if(!cap.isOpened())
    {
        cout << "Error opening video stream" << endl;
        return -1;
    }

    // Default resolution of the frame is obtained.The default resolution is system dependent.
    int frame_width = cap.get(CV_CAP_PROP_FRAME_WIDTH);
    int frame_height = cap.get(CV_CAP_PROP_FRAME_HEIGHT);

    // Define the codec and create VideoWriter object.The output is stored in 'outcpp.avi' file.
    VideoWriter video("outcpp-.avi",CV_FOURCC('M','J','P','G'),10, Size(frame_width,frame_height));
    while(1)
    {
        Mat frame;

        // Capture frame-by-frame
        cap >> frame;

        // If the frame is empty, break immediately
        if (frame.empty())
            break;

        // Write the frame into the file 'outcpp.avi'
        video.write(frame);

        // Display the resulting frame
        imshow( "Frame", frame );

        // Press  ESC on keyboard to  exit
        char c = (char)waitKey(1);
        if( c == 27 )
            break;
    }

    // When everything done, release the video capture and write object
    cap.release();
    video.release();

    // Closes all the windows
    destroyAllWindows();
    return 0;
}

如果它能正常工作，你遇到的问题和我们一样 :) 我想QT在使用OpenCV的视频编写器方面存在问题。欢迎加入我们的行列。

另一方面，你有找到解决方案吗？

- Rahibe Meryem