Advanced search

On other websites (13170)

• FFMPEG thumbnail in php application's is not rotated properly

  4 September 2015, by Vignesh

  I have created a FFMPEG thumbnail in a php application and tried to rotate the thumbnail image if the video is bottom up(reversed).But the image rotate is not working properly.
  The below is the code for image rotation

  $video = $storeHere.$mediaFile;
  
                                  $tImage = $upload_output['uploaded_file'].'.jpg';
  
                                  $thumbnail = $storeHere.$tImage;
  
                                  // shell command [highly simplified, please don't run it plain on your script!]
  
                                   shell_exec("ffmpeg -i $video -deinterlace -an -ss 1 -t 00:00:01 -r 1 -y -vcodec mjpeg -f mjpeg -s 250x250  $thumbnail 2>&1");
  
                                   /* image rotate fix */
  
                                      $source = imagecreatefromjpeg($thumbnail);
  
                                      $degrees = 270;
  
                                      $rotate = imagerotate($source, $degrees, 0);
  
                                      imagejpeg($rotate,$thumbnail);
  
                                   /* rotate fix ends */

• Scaling Application for video decoding using ffmpeg

  6 July 2020, by jasoos

  I am building an application to read multiple IP camera streams (rtsp) and run different Machine Learning Algorithms over it in real time. For each camera stream,

  


  

  1. I spawn an ffmpeg process which continuously break the rtsp streams
into frames and store them as images (JPEG). The streams use H.264
encoding. I am taking 1 frame every second as output.

  


  2. Message queues corresponding to models are given the message
containing location of the file.

  


  3. Models keep on picking up the file and drawing inferences

  


  


  The problem I am facing is the CPU usage by ffmpeg decoding process. For real time inference without any loss of frames, I have to beef up my server by a core for every 2 camera streams. Is there any optimization I am missing for ffmpeg?

  


  I am using Intel Xeon Gold processor with Ubuntu 18.04 OS

  


• How can I create a c++ console application which makes use of an open source c project

  2 October 2018, by Bogdan Daniel

  I’ve been playing around with a compiled version of https://github.com/FFmpeg/FFmpeg. But it has some problems, during the closing of an opened stream using avio_close(it takes a really long time to close it).

  I’ve been trying to understand what could go wrong by reading through the implementation, but couldn’t find anything.

  What I would like to do, is to actually have a C++ console application which uses the c files and to debug them while running the code(using breakpoints and so on).

  Unfortunately I cannot find any information on how to set it up. Simply copying the files in a new console application is not enough.

  Thanks in advance for any suggestions.

  Edit: I can already see a closing vote. If this question is not appropriate for this website, I will delete it. But please point me in the right direction of where to post it.Although it is quite a general question, I believe that it is clear and enough information has been provided.

  Edit2: Yes, I was a bit unclear about what I’m using.

  I’m using Visual Studio Community 2017 on Windows 10 for creating the C++ console application.

  Edit3:

  Steps that I’ve taken into using the source files into my console application which was using the DLLs.

  1. Copy all of the contents of the FFmpeg-master to my console application
  2. Include all of them in the c++ console application project
  3. Run a build - takes forever and has infinite build errors( > 1000) - probably compiler related

  Edit4:

  I have no actual errors with avio_close, it just takes too long to close the stream. What I found out when playing around with the settings is that when the fifo_size parameter is set, closing the stream is a lot faster depending on how small the set value is. And it sort of makes sense since fifo_size is related to the packet size, but I haven’t found out where in the code this size has an impact.

  fifo_size=units
  Set the UDP receiving circular buffer size, expressed as a number of packets with size of 188 bytes. If not specified defaults to 7*4096.

  Edit5: I still haven’t found a way to compile the open source ffmpeg project into libs, dlls and pdbs. Am I the first one needing such files(seems unrealistic)?
  The only tool capable of delivering those so far is vcpkg. The only problem is that it compiles the 3.3.3 version and the latest is 4.0.2 .

  I tried to modify the vcpkg\ports\ffmpeg\portfile.cmake file to include the latest version of ffmpeg, but it doesn’t build it.

  Are there any other suggestions?