cv::VideoWriter with CAP_OPENCV_MJPEG api creates broken (or just unfinished) video file. #24171
Description
System Information
OpenCV version: 4.8.0
Windows 11
Microsoft Visual Studio 2022 64bit
Detailed description
If I create a certain video using cv::VideoWriter with CAP_OPENCV_MJPEG api, I can load the video correctly using cv::VideoCapture, but I get an error message during loading.
[mjpeg @ 0000015a20f1df00] error count: 268435456
[mjpeg @ 0000015a20f1df00] error y=0 x=0
Also I can watch the created video using Windows Media Player without any errors.
If I create the same video using CAP_FFMPEG api, I don't get error messages.
The error reproduces only on a certain video content, so I can create a different video with the same size without error messages.
Steps to reproduce
#include <opencv2/highgui.hpp>
#include <opencv2/imgcodecs.hpp>
#include <opencv2/imgproc.hpp>
#include <iostream>
int w = 16;
int h = 16;
int num_frames = 1;
void saveVideo(std::string filename, cv::VideoCaptureAPIs api, long base_color) {
cv::VideoWriter writer(filename, api, cv::VideoWriter::fourcc('M', 'J', 'P', 'G'), 30, cv::Size(w, h), true);
for (long i = 0; i < num_frames; ++i) {
cv::Mat frame1(h, w, CV_8UC3);
for (long x = 0; x < w; x++) {
for (long y = 0; y < h; y++) {
frame1.at<cv::Vec3b>(y, x) = cv::Vec3b((base_color * x) % 256, base_color + 2, base_color + 3);
}
}
writer.write(frame1);
}
writer.release();
}
void loadVideo(std::string filename) {
std::cout << "===== loading " << filename << std::endl << std::flush;
cv::VideoCapture cap(filename, cv::CAP_FFMPEG);
if (!cap.isOpened()) {
std::cout << "No video stream detected" << std::endl;
return;
}
cv::Mat frame;
uint32_t frame_cnt = 0;
while (true) {
cap >> frame;
if (frame.empty()) {
break;
}
}
cap.release();
std::cout << "===== loaded " << filename << std::endl << std::flush;
}
int main(int argc, char* argv[]) {
saveVideo("out1.avi", cv::CAP_FFMPEG, 147);
saveVideo("out2.avi", cv::CAP_FFMPEG, 146);
saveVideo("out3.avi", cv::CAP_OPENCV_MJPEG, 147);
saveVideo("out4.avi", cv::CAP_OPENCV_MJPEG, 146);
loadVideo("out1.avi");
loadVideo("out2.avi");
loadVideo("out3.avi");
loadVideo("out4.avi"); // prints error message
}
Issue submission checklist
- I report the issue, it's not a question
- I checked the problem with documentation, FAQ, open issues, forum.opencv.org, Stack Overflow, etc and have not found any solution
- I updated to the latest OpenCV version and the issue is still there
- There is reproducer code and related data files (videos, images, onnx, etc)