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• Add watermark with text effect using drawtext ffmpeg

  27 mars 2023, par mandesk

  i try to search to find the way make the watermark add in video like image using ffmpeg, but too hard for me, anyone help me, using drawtext can make the watermark like that ?
is transparency with burn light effect or something like Double Exposure

  


  


  


• x264 encoding taking longer when encoding static frames (than

  14 septembre 2015, par Danilo

  ​Hi,
  I’m using x264 for live video streaming and I’ve noticed that the thread
  responsible for encoding uses ​​more cpu (sometimes 50% more with 1920x1080) when the video stream is frozen (i.e. : camera is sending the same frame over an over again) or when I make it encode the same image over and over again.

  This seems somewhat counter intuitive to me, as I would expect x264 to use
  more processing power when encoding complex scenes other then static ones.

  My encoder settings are the following :

  1280x720 fps=25/1 timebase=0/0 bitdepth=8 cabac=0 ref=1 deblock=1:0:0 analyse=0x3:0x113
  
  me=hex subme=2 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1
  
  8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=1 lookahead_threads=0
  
  sliced_threads=0 slice_max_size=1190 nr=60 decimate=1 interlaced=0 bluray_compat=0
  
  constrained_intra=0 bframes=0 weightp=0  keyint=1200 keyint_min=120 scenecut=40
  
  intra_refresh=0 rc_lookahead=0 rc=crf mbtree=0 crf=24.0 qcomp=0.60 qpmin=0 qpmax=69
  
  qpstep=4 vbv_maxrate=1024 vbv_bufsize=350 crf_max=35.0 nal_hrd=none

  I created a github gist based on the example.c encoder bundled in x264’s
  source code and tested encoding times with it. (You can find it here :
  https://gist.github.com/danilogr/ab4976ff4e0831ab274b)

  Average encoding time for the static scene is 38% bigger than for a scene
  with movements. (You can find my test case and also the output from my test
  encoder on the link above).

  ​​
  ​I’ve also noticed that by setting ​​scenecut=0, subme=0, trellis=0 and me=dia I can get rid of this problem​, but with noticeable quality​ decrease.

  ​
  ​Could anyone, please, shed some light on the reasons for this odd behavior ?
  ​Also, what can be done in order to avoid this situation without a major decrease in quality ?​

• FFMpeg with libstagefright for hardware encoding jpeg images to mp4 on Android

  16 septembre 2015, par HashG

  I have compiled FFMpeg with libstagefright for Android. I know this can be used for hardware decoding but I would like to use it for hardware encoding a stream of jpeg images to mp4 video. Could someone please shed some light on this.

  I have looked at the post below where Alex Cohn says "Alternatively, you can compile ffmpeg with libstagefright, and it will use hardware avc encoder." - android-how-to-encode-a-stream-of-images-to-h264-with-hardware-acceleration

  Could someone explain how to do this. I have compiled ffmpeg with the following options :

  --disable-avdevice
  
  --disable-decoder=h264
  
  --disable-decoder=h264_vdpau
  
  --enable-libstagefright-h264

  All this relates to enabling hardware decoding but what would I need to specify to enable hardware encoding ?

  My ffmpeg command to convert the images into a video looks like this :

  ffmpeg.execute(new String[]{"-framerate",
  
                  "25",
  
                  "-i",
  
                  "/images_directory/image%07d.jpg",
  
                  "-c:v",
  
                  "libx264",
  
                  "-preset",
  
                  "ultrafast",
  
                  "-tune",
  
                  "zerolatency",
  
                  "-r",
  
                  "25",
  
                  "-pix_fmt",
  
                  "yuv420p",
  
                  "output.mp4"})

  What should I change to enable hardware encoding ?