Newest 'ffmpeg' Questions - Stack Overflow

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• How can I make ffmpeg executable file separately by using gcc command ?

  8 juillet 2017, par koseonjae

  actually, my goal is to use ffmpeg on Qt platform. But tow of them is unfamiliar with me.. I tried command on ./ffmpeg directory after build (./configure, make, sudo make install) as below on Mac (os x) 10.12.4 (Sierra)

  $ gcc ffmpeg.c -o a.out -I /usr/local/include -I /Users/koseonjae/ffmpeg -L /usr/local/lib -lavdevice -lavutil -lavformat -lavcodec -lavutil -lx264 -lvpx -lvorbisenc -lvorbis -ltheoraenc -ltheoradec -logg -lmp3lame -lbz2 -lz -lxslt -lfdk-aac -liconv -lopus -lx265 -lxvidcore -lpng16 -lswresample -framework CoreFoundation -framework CoreServices -framework AudioUnit -framework AudioToolbox -framework CoreAudio -framework AVFoundation -framework CoreMedia -framework CoreVideo -framework CoreAudio -framework Foundation -framework Security -framework VideoDecodeAcceleration -framework VideoToolbox

  I added many library, but result is as below

  /Users/koseonjae/ffmpeg/ffmpeg2.h:157:8: error: unknown type name 'BOOL' static BOOL WINAPI CtrlHandler(DWORD fdwCtrlType);

  /Users/koseonjae/ffmpeg/ffmpeg2.h:157:19: error: expected ';' after top level declarator static BOOL WINAPI CtrlHandler(DWORD fdwCtrlType);

  ---

  what library should I add?? thank you!

• Diagonal Split using ffmpeg

  8 juillet 2017, par Jeffin

  I am trying to acheive the following effect using ffmpeg

  

  I have tried multiple options , but failed so far,

  I have referred the following questions , not happening for me

  • FFmpeg: Add alpha channel to a video using a PNG mask
  • FFMPEG Crop with side by side merge
  • https://superuser.com/questions/916431/ffmpeg-filter-to-boxblur-and-greyscale-a-video-using-alpha-mask?rq=1

  I have three videos but i have somewhat acheived the diagonal split for two videos using the following code , but still couldnt get the output for three videos or four

  ffmpeg -i input0 -i input1 -filter_complex \
  "[1:v][0:v]blend=all_expr=if(gt(X\,Y*(W/H))\,A\,B)" output
  

• Add text to image using AForge.Video.FFMEG in C#

  8 juillet 2017, par Ratzz

  Using AForge.Video.FFMPEG I am able to create video from Images.

          string[] files;
          string folderPath = @"FolderPath";
          files = Directory.GetFiles(folderPath).OrderBy(c => c).ToArray();
  
          VideoFileWriter writer = new VideoFileWriter();
          writer.Open(@"C:folder\new.mp4", imageWidth, imageHeight, 10, VideoCodec.MPEG4);
          for (int j = 0; j < files.Length; j++)
          {
              string fileName = files[j];
              BitmapSource imageBitMap = new BitmapImage(new Uri(fileName, UriKind.RelativeOrAbsolute));
              imageBitMap.Freeze();
              int stride = imageBitMap.PixelWidth * ((imageBitMap.Format.BitsPerPixel + 7) / 8);
              byte[] ImageInBits = new byte[imageBitMap.PixelWidth * imageBitMap.PixelHeight];
              imageBitMap.CopyPixels(ImageInBits, stride, 0);
  
              Bitmap image = new Bitmap(imageWidth, imageHeight, stride, PixelFormat.Format8bppIndexed, Marshal.UnsafeAddrOfPinnedArrayElement(ImageInBits, 0));
  
              writer.WriteVideoFrame(image);
              image.Dispose();
          }
  

  I am trying to add text/String to input image using

      private Bitmap WriteString(Bitmap bmp)
      {
          RectangleF rectf = new RectangleF(70, 90, 90, 50);
  
          Bitmap tempBitmap = new Bitmap(bmp.Width, bmp.Height);
          Graphics g = Graphics.FromImage(tempBitmap);
  
          g.DrawImage(bmp, 0, 0);
          g.SmoothingMode = SmoothingMode.AntiAlias;
          g.InterpolationMode = InterpolationMode.HighQualityBicubic;
          g.PixelOffsetMode = PixelOffsetMode.HighQuality;
          g.DrawString("yourText", new Font("Tahoma", 8), Brushes.Red, rectf);
          g.Flush();
  
          return bmp;
      }
  

  like

              Bitmap image = new Bitmap(imageWidth, imageHeight, stride, PixelFormat.Format8bppIndexed, Marshal.UnsafeAddrOfPinnedArrayElement(ImageInBits, 0));
              Bitmap outputBitmap=WriteString(image);
              writer.WriteVideoFrame(outputBitmap);
  

  How can I write a string to Image?

  Is there any way to add subtitle to AForge.Video.FFMEG to image before creating video?

• extract NAL units bitstream from an MP4 video

  8 juillet 2017, par lighting

  Is it possible to extract every NAL units bitstream? (the actual bitstream)

  for example extract them like this:

  (4byte length + the remaining bytes till the end of the unit) and do this for all the units in a MP4 video? actually i want to check the occurrence of the 2 bytes after the 4byte length in a MP4 video (coded with H.264 codec). can i use FFmpeg for this?

  Thanks!

• compress MP4 file using FFMPEG and PHP

  8 juillet 2017, par user2692997

  hello i am new to ffmpeg and am having trouble implementing it on my server i have managed to install it and found some code to confirm its working however i am trying to set the frame width and height but i am having no luck

  what i need help with - change frame width n height to something like 400 by 800 - any other changes you can recommend from experience for compressing mp4 for download - save and overwrite existing file

  this is the code i found to test ffmpeg

  extension_loaded('ffmpeg') or die('Error in loading ffmpeg');
  $vid = realpath('rc.mp4');
  $ffmpegInstance = new ffmpeg_movie($vid);
  echo "getDuration: " . $ffmpegInstance->getDuration() . "
  ".
  "getFrameHeight: " . $ffmpegInstance->getFrameHeight() . "
  ".
  "getFrameWidth: " . $ffmpegInstance->getFrameWidth() . "
  ".
  "hasAudio: " . $ffmpegInstance->hasAudio();