我正在使用Linux内核4.9.35-ti-r44在ARM BeagleBone X-15 Debian机器上运行。在我的C ++（Qt 5）应用程序中，我想将cv :: Mat帧保存为MP4格式的视频。我从头开始安装了libx264并编译了ffmpeg和OpenCv。我可以使用AVI视频容器类型而不是MP4成功地使用MJPEG录制和观看视频。每当我尝试编写MP4视频时，我都会遇到以下形式的运行时错误：
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/' ???'
我尝试了各种谷歌答案，但没有一个有效。
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的视频编写器写入MP4文件？
当我尝试'X'，'2'，'6'，'4'格式时，我收到错误：
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“X”，“V”，“我”，“D”格式时，我收到错误：
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'M'，'P'，'E'，'G'格式时，我收到错误：
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
当我尝试'H'，'2'，'6'，'4'格式时，我收到错误：
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'M'，'P'，'4'，'V'格式时，我收到错误：
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'A'，'V'，'C'，'1'格式时，我收到错误：
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'D'，'我'，'V'，'X'格式时，我收到错误：
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0x21格式时，我收到错误：
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
这是我的完整课程，其中显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'，不幸的是，这也不起作用：
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X264 FOURCC时，mp4文件是48个字节，永远不会增长：
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'
静态尺寸：
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
这是我的ffmpeg构建conf：
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
答案 0 :(得分：0)
我也遇到过类似的问题，但是在MacOS上运行。我通过将X264库重新安装到最新版本来解决该问题，然后使用./configure --enable-libx264 --enable-gpl --enable-avresample --enable-shared重新安装FFMPEG，以将新的X264正确链接到FFMPEG。然后，重新安装OpenCV（我正在使用3.4.4版）以链接新的FFMPEG。构建OpenCV时，请确保WITH FFMPEG为ON，否则将使用内置的OpenCV编码器，这将为您提供更多的选择。
答案 1 :(得分：-1)
你是否曾在普通的C ++ 11中尝试过：
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;
}
如果它正常工作你遇到了我们遇到的同样的问题:) QT对我假设的videowriter Opencv有问题。欢迎来到俱乐部。
另一方面，您找到了解决方案吗？