I'm running on an ARM BeagleBone X-15 Debian machine with Linux Kernel 4.9.35-ti-r44. In my C++ ( Qt 5 ) application, I want to save my cv::Mat frames to an MP4 format video. I have libx264 installed and compiled from scratch both ffmpeg and OpenCv. I can successfully record and view video with MJPEG with the AVI video container type but not MP4. Whenever I try to write an MP4 video, I get run time errors of the form:
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/' ???'
I've tried various Google answers but none have worked.
Relevant code:
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);
I've downloaded and built the latest OpenCV 3.4 but the problem persists. How can I write to an MP4 File with OpenCV's video writer?
When I try the 'X','2','6','4' format I get the error:
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
When I try the 'X','V','I','D' format I get the error:
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
When I try the 'M','P','E','G' format I get the error:
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
When I try the 'H','2','6','4' format I get the error:
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
When I try the 'M','P','4','V' format I get the error:
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
When I try the 'A','V','C','1' format I get the error:
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
When I try the 'D','I','V','X' format I get the error:
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
When I try the 0x21 format I get the error:
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
Here is my complete class which shows all tried formats:
#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();
}
Update - I tried 'a','v','c','1' and unfortunately that also does not work:
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
When I try the X264 FOURCC, the mp4 file is 48 bytes and never grows:
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'
Static Size:
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
Here is my ffmpeg build 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