Recherche avancée

Sur d’autres sites (8870)

• Issue with image rotation using JavaCV library

  26 février 2015, par intrepidkarthi

  I am writing an Android application which records video for a specified amount of time. Everything works fine if I record using the smartphone’s back camera. The app has a feature to pause/record feature like in Vine app. The issue comes when recording using the device’s front camera. The video surface frame looks fine when storing/playing the video the video is upside down. There is a lot of things discussed about this issue everywhere. But I didn’t find any solution that WORKS.

  Have a look at the code and image mentioned below.

  Here is the original image taken from front camera. I have turned it upside down for a better view.

  

  Here is what I actually get after rotation :

  

  Method :

       IplImage copy = cvCloneImage(image);
  
       IplImage rotatedImage = cvCreateImage(cvGetSize(copy), copy.depth(), copy.nChannels());
  
       //Define Rotational Matrix
  
       CvMat mapMatrix = cvCreateMat(2, 3, CV_32FC1);
  
  
  
       //Define Mid Point
  
       CvPoint2D32f centerPoint = new CvPoint2D32f();
  
       centerPoint.x(copy.width() / 2);
  
       centerPoint.y(copy.height() / 2);
  
  
  
       //Get Rotational Matrix
  
       cv2DRotationMatrix(centerPoint, angle, 1.0, mapMatrix);
  
  
  
       //Rotate the Image
  
       cvWarpAffine(copy, rotatedImage, mapMatrix, CV_INTER_CUBIC + CV_WARP_FILL_OUTLIERS, cvScalarAll(170));
  
       cvReleaseImage(copy);
  
       cvReleaseMat(mapMatrix);

  I have tried doing

       double angleTemp = angle;
  
  
  
       angleTemp= ((angleTemp / 90)%4)*90;       
  
       final int number = (int) Math.abs(angleTemp/90);
  
  
  
       for(int i = 0; i != number; ++i){            
  
           cvTranspose(rotatedImage, rotatedImage);
  
           cvFlip(rotatedImage, rotatedImage, 0);           
  
       }

  Ends up in throwing exception saying that source and destination doesn’t match with number of columns and rows.

  Update :

  Video is recorded in this way.

  IplImage newImage = null;
  
  if(cameraSelection == CameraInfo.CAMERA_FACING_FRONT){
  
      newImage = videoRecorder.rotate(yuvIplImage, 180);
  
      videoRecorder.record(newImage);
  
  }
  
  else
  
      videoRecorder.record(yuvIplImage);  

  Rotation is done in this way :

      IplImage img = IplImage.create(image.height(), image.width(),
  
              image.depth(), image.nChannels());
  
  
  
      for (int i = 0; i < 180; i++) {
  
          cvTranspose(image, img);
  
          cvFlip(img, img, 0);
  
      }

  Can anyone point out what is wrong here if you have experienced this before ?

• How to edit or add video metadata of “rotation” in ts ?

  17 février 2017, par Chienchia Chang

  The source video file is flv format, and I want to remux it to ts format. I want to rotate the ts file by anticlockwise 90 degress, if so, I must decode and recode the file to use avfilter, and the process cost a lot. I want to know whether I can add metadata to the object ts file, and the player can rotate the ts file by the metadata when playing.

• Difficulty linking filter graph with ffmpeg_next (rust-ffmpeg)

  2 mai 2023, par anvlkv

  I'm using rust ffmpeg_next::filter::Graph to create a concat filter which should accept 3x2 inputs

  


  filter.add(&filter::find("buffersink").unwrap(), "out_v", "").unwrap();
filter.add(&filter::find("abuffersink").unwrap(), "out_a", "").unwrap();
filter.add(&filter::find("buffer").unwrap(), "in_v_0", &args_v0).unwrap();
filter.add(&filter::find("buffer").unwrap(), "in_v_1", &args_v1).unwrap();
filter.add(&filter::find("buffer").unwrap(), "in_v_2", &args_v2).unwrap();
filter.add(&filter::find("abuffer").unwrap(), "in_a_0", &args_a0).unwrap();
filter.add(&filter::find("abuffer").unwrap(), "in_a_1", &args_a1).unwrap();
filter.add(&filter::find("abuffer").unwrap(), "in_a_2", &args_a2).unwrap();
filter.input("out_v", 0).unwrap()
   .input("out_a", 0).unwrap()
   .output("in_v_0", 0).unwrap()
   .output("in_v_1", 0).unwrap()
   .output("in_v_2", 0).unwrap()
   .output("in_a_0", 0).unwrap()
   .output("in_a_1", 0).unwrap()
   .output("in_a_2", 0).unwrap()
   .parse("[in_v_0][in_a_0][in_v_1][in_a_1][in_v_2][in_a_2]concat=n=3:v=1:a=1[out_v][out_a]")
   .unwrap();
filter.validate().expect("invalid filter");


  


  My validate call fails with Output pad "default" with type audio of the filter instance "in_a_0" of abuffer not connected to any destination

  


  It seems it may have to do with ffmpeg_next using avfilter_graph_parse_ptr as this stackoverflow suggests

  


  I've tried using avfilter_graph_parse2 and adding all my sinks and buffers to the spec :

  


  buffer=width=1280:height=720:pix_fmt=yuv420p:time_base=1/15360:sar=1[in_v_0];
abuffer=time_base=1/48000:sample_rate=48000:sample_fmt=fltp:channel_layout=0x3[in_a_0];
buffer=width=1280:height=720:pix_fmt=yuv420p:time_base=1/15360:sar=1[in_v_1];
abuffer=time_base=1/48000:sample_rate=48000:sample_fmt=fltp:channel_layout=0x3[in_a_1];
buffer=width=1280:height=720:pix_fmt=yuv420p:time_base=1/15360:sar=1[in_v_2];
abuffer=time_base=1/48000:sample_rate=48000:sample_fmt=fltp:channel_layout=0x3[in_a_2];
[in_v_0][in_a_0][in_v_1][in_a_1][in_v_2][in_a_2]concat=n=3:v=1:a=1[out_v][out_a];[out_v]buffersink;
[out_a]abuffersink


  


  Which then fails with Input pad "default" with type video of the filter instance "out_v" of buffersink not connected to any source

  


  I hope someone can help me understand...