Recherche avancée

Sur d’autres sites (5671)

• ffmpeg command to scale, show images at exactly 130bpm [closed]

  17 août 2023, par S. Imp

  I have a sequence of images which I would like to display to some music that plays at 130bpm. I'll also need to scale the images, which are a rather strange 2673x2151 pixels each down to something, ideally something that would fit without stretching inside a 1080p frame — e.g. 1342x1080.

  


  130BPM yields weirdness with frame rates. There are 2.16666666667 (13/6) beats per second. This being the case, I can't figure out how many frames to show each each image at the usual frame rates (24, 25, 30 fps). If I could make a movie with a frame rate of 2.16666667 frames per second, i could simply show each image for one frame. This seems like it might actually be optimal — it would probably make a a very compact video file, right ??

  


  Alternatively, if we must set the frame rate to an positive integer value, 13 frames per second works if we just display each image for six frames. 13 FPS means 780 frames per minute. 780 frames divided by 130 beats means 6 frames per beat.

  


  Finally, my images are named j1.jpg, j2.jpg, j3.jpg, etc.

  


  Can someone help me concoct an ffmpeg command to assemble these images into a video with each image lasting one beat at 130BPM ? I've been trying to massage this command, which does assemble the images into a movie, but my attempts to specify a frame rate have had weird effects. E.g., doing a -r results in strange videos that change image very erratically. I think it's because there's a setpts=N/25/TB bit in there.

  


  ffmpeg -pattern_type glob -i "j*.jpg" -filter_complex "[0]reverse[r];[0][r]concat,loop=2:250,setpts=N/25/TB,scale=1342:1080" -pix_fmt yuv420p -c:v libx264 -preset slow -b:v 3500k output_looped.mp4


  


  Also, I don't understand what the 250 means in loop=2:250. If someone could explain that to me, I'd be grateful.

  


• Powerpoint can't show a video with headers. I see green screen

  28 novembre 2017, par zinon

  I’ve created a video using ffmpeg that contains headers.

  My script for creating it is :

  ffmpeg.exe -f rawvideo -vcodec rawvideo -s 560x448 -r 40 -pix_fmt yuv420p -i C_L_560x448_40_static_maxSSIM_QP23_B2.yuv -vcodec rawvideo -qscale 0 -filter_complex "drawtext=fontsize=32: fontfile=FreeSerif.ttf: text='SSIM=0.961': x=(w-tw)/2: y=(lh/2): fontcolor=orange, drawtext=fontsize=22: fontfile=FreeSerif.ttf: text='Bitrate≤1800 [1873 kbps], Frame rate≥40 [43.98 fps]': x=(w-tw)/2: y=(lh/2+30): fontcolor=orange : box=1: boxcolor=0x00000099, drawbox=x=80:y=160:w=220:h=135:color=red@0.5" C_L_560x448_40_static_maxSSIM_QP23_B2_new.avi

  Firstly, media player showed it as green screen. I downloaded

  Media Player Codec Pack

  and now show its correclty.

  However, when I insert it in powerpoint 2016 I have the same problem of green screen. Do you know how to fix this ?

  vlc player can play it correctly. Is there any way to change the player of excel and use vlc player instead ?

• fftools/ffmpeg : change fps progress log message to show two decimal digits

  28 avril 2018, par André Camargo

  fftools/ffmpeg : change fps progress log message to show two decimal digits
  Useful when transcoding videos at 29.97 fps because delivers a more accurate result for monitoring.
  Signed-off-by : Michael Niedermayer <michael@niedermayer.cc>
  

  • [DH] fftools/ffmpeg.c