Recherche avancée

Sur d’autres sites (8684)

• encode x264(libx264) raw yuv frame data

  12 janvier, par Mohamed El-Sayed

  I am trying to encode an MP4 video using raw YUV frames data, but I am not sure how can I fill the plane data (preferably without using other libraries like ffmpeg)

  



  The frame data is already encoded in I420, and does not need conversion.

  



  Here is what I am trying to do :

  



  const char *frameData = /* Raw frame data */;

x264_t *encoder = x264_encoder_open(&param);
x264_picture_t imgInput, imgOutput;
x264_picture_alloc(&imgInput, X264_CSP_I420, width, height);

// how can I fill the struct data of imgInput

x264_nal_t *nals;
int i_nals;
int frameSize = x264_encoder_encode(encoder, &nals, &i_nals, &imgInput, &imgOutput);


  



  The equivalent command line that I have found is :

  



   x264 --output video.mp4 --fps 15 --input-res 1280x800 imgdata_01.raw 


  



  But I could not figure out how the app does it.

  



  Thanks.

  


• Video created with ffmpeg won't play in video player

  11 octobre 2014, par user3180253

  I’m using Python to create a video using ffmpeg. The following code is what I’m using...

  import subprocess as sp
  
  import Image
  
  FFMPEG_BIN = "ffmpeg"
  
  
  
  commandWriter = [ FFMPEG_BIN,
  
                '-y',
  
                '-f', 'image2pipe',
  
                '-vcodec','mjpeg',
  
                '-s', '480x360', # size of one frame
  
                '-pix_fmt', 'rgb24',
  
                '-r', '29', # frames per second
  
                '-i', '-',
  
                '-an', # Tells FFMPEG not to expect any audio
  
                '-vcodec', 'mpeg4',
  
                '-qscale', '5',
  
                '-r', '29',
  
                '-b', '250',
  
                './fire.mp4' ]
  
  
  
  pipeWriter = sp.Popen(commandWriter, stdin=sp.PIPE)
  
  
  
  fps, duration = 24, 10
  
  for i in range(fps*duration):
  
     im = Image.new("RGB",(480,360),(i%250,1,1))
  
     im.save(pipeWriter.stdin, "JPEG")
  
  pipeWriter.stdin.close()
  
  pipeWriter.wait()
  
  
  
  pipeWriter.terminate()

  After running the above code, I get an output video with a data rate of 214 kbps. This video won’t play in Windows Media Player. At first I was at a loss of how to get the video to play, so I compared it to another video that I downloaded. I noticed the only real difference was in the bit rates/data rates. I ran this command from the command line...

  ffmpeg -i fire.mp4 -b:v 250k -bufsize 250k water.mp4

  which as I understand it takes fire.mp4 and simply outputs a new video with a modified bit rate. This new output works when I open it in Windows Media Player.

  The question I’m asking is how can I do this straight from Python ? I’ve tried adding a -b option to commandWriter (as shown) but this does not work. I’ve also added a bufsize = 10**8 in my pipeWriter but that does not work either.

  Overall what I’m trying to accomplish is taking a video input.mp4, modifying each frame as I load it in memory, and then writing that frame to a new file output.mp4. So far ffmpeg is looking like the best tool ’cause I can’t get OpenCV to work at all.

  So if anyone has a way to have a water.mp4 output file be able to run in Windows Media Player without needing to have that additional command line code run or a better way to complete my overall task, I would much appreciate that.

• My Android app release is too big than expected

  11 avril 2020, par Abhi Jith

  I have created a simple android app to download the whatsapp status

  



  I have completed all the functionalities.then the app size is less than 5MB


  



  After that i added a third party plugin to add my app name to the downloaded video files as watermark

  



  i used ffmpeg to add water mark in the video


  



  But after that my app release size reached around 20MB.

  



  I used minifyEnabled true to shrink the code.but doesn't worked


  



  How to reduce my release size