Recherche avancée

Sur d’autres sites (9872)

• FFMPEG Video to still images and back to video loss less

  4 novembre 2012, par Rigoni

  I'm trying to extract image from an uncompressed AVI video using ffmpeg with the command :

      ffmpeg -i sorce.avi -f image2 -pix_fmt bgr24 images/%1d.bmp

  All is ok, but now I need to revert these images back to a video file.
  I'm trying using this command :

      ffmpeg -f image2 -r 24 -i marked/%1d.bmp -y -vcodec ffv1 -pix_fmt bgr24 test.avi

  But, the output video is compressed and with bad quality.

  Is there any way to extract the images in RGB format and than back to a lossless video ?

  I also tryed to use -vcodec rawvideo, but the quality still bad.

  Best regards.

• To concat two videos, one of which is the first video webcam recorder and the other is the normal video(Mp4) using ffmpeg

  8 décembre 2020, par Zargam Husayn

  Two videos have to be join in which the first video is a webcam recorder and the other is a normal video in which the first video I set up plays correctly but the second video does not play, only the audio is heard.

  


   foreach ($video as $value) {
            exec("ffmpeg -i ".$this->APP_PATH.$value." -c:v libx264 -c:a aac -b:a 192k ".$this->TEMP_PATH.++$this->temp_file.".mp4");
            exec("ffmpeg -i ".$this->TEMP_PATH.$this->temp_file.".mp4 -c:a aac -ar 48000 -ac 2 -c:v copy -video_track_timescale 600 ".$this->TEMP_PATH.++$this->temp_file.".mp4");
            $text .= "file '".$this->TEMP_PATH.$this->temp_file.".mp4'\n";
        }
        
        $file = $this->TEMP_PATH.++$this->temp_file.".txt";
        //chmod($this->TEMP_PATH, 0777);
        file_put_contents($file,$text);
        chmod($file, 0777);

        Log::info(" ********** file paths ********** ".$text);

        exec("ffmpeg -safe 0 -f concat -i ".$file." -c copy ".$this->TEMP_PATH.$this->final);


  


• Extracting parts of video and make a new video with them [on hold]

  13 février 2014, par Filippo

  I need to extract parts of a video and make a video (in order to make a summary).
  My videos are mostly mpg, sometimes avi.

  I'm using ffmpeg to do it :

  Extraction : ffmpeg -ss XX -t XX -i video.mpg -vcodec copy -acodec copy partX.mpg

  Concatenation : ffmpeg -i concat:part1.mpg|part2.mpg|... -vcodec copy -acodec copy summary.mpg

  I have two problems :

  • ffmpeg only let me set position by time reference and not by frame number. I will prefere to set it by frame number, but it's not a big deal
  • the resulting video is...bad. The transitions between extracted parts are not smooth at all.

  What is the best way to do that ?
  I guess I need some kind of non-linear editing library : gnonlin, gtreamer-editing-services (but no package for Fedora 16 ?), MLT...

  But how I can do that easily ? (in preference in python)

  I can't find any good example.

  Thanks.