Recherche avancée

Sur d’autres sites (5864)

• encode 3 different mp4 video to a standard, then join them without encoding [closed]

  10 novembre 2023, par Joe Cook

  I've found many topics on this but none seem to work fully. when I encode them, they look like specs are equal, but when I join them they stutter and freeze.

  


  outputa.mp4 2304/1536    9.7 frame/rate   security camera no audio
outputb.mp4 1140/720   29.91 frame/rate   phone portrait
outputc.mp4 1920/1080  29.91 frame/rate   phone landscape


  


  padding looks good, and resolution is the same, joining stutters/freezes

  


  'ffmpeg\bin\ffmpeg -y -i outputc.mp4 -vf "[in]scale=iw*min(2304/iw\,1536/ih):ih*min(2304/iw\,1536/ih)[scaled]; [scaled]pad=2304:1536:(2304-iw*min(2304/iw\,1536/ih))/2:(1536-ih*min(2304/iw\,1536/ih))/2[padded]; [padded]setsar=1:1[out]" -c:v libx264 -c:a copy temp\output3.mp4'


  


  padding looks good, and resolution is the same, framerate same, joining stutters/freezes

  


  'ffmpeg\bin\ffmpeg -y -i output3.mp4 -vf "scale=2304:1536:force_original_aspect_ratio=decrease,pad=2304:1536:(ow-iw)/2:      (oh-ih)/2,setsar=1:1,fps=fps=30,settb=AVTB,setpts=PTS-STARTPTS" -vcodec libx264 -pix_fmt yuv420p outputc.mp4'


  


  when I join it stutters and freezes

  


  'ffmpeg -f concat -safe 0 -i list.txt -c:v copy -c:a copy output.mp4'

  


• Playing video with transparency in iOS

  14 juillet 2020, par 0Ds0

  A bit of background, i want to play videos with transparency on the web converted from gifs, for all non apple devices i can easily export a webm file like so

  


  ffmpeg -i test.gif -c:v libvpx-vp9 -qmin 0 -qmax 18 -crf 9 -b:v 1400K -quality good -cpu-used 0 -auto-alt-ref 0 -pix_fmt yuva420p -an -sn  -metadata title="test webm" test.webm

  


  No need for video streaming with HTTP response 206 partial content loaded it works out of the box

  


  Now for safari and apple devices i am presented with a totally different beast i set up a endpoint that serves the video with HTTP 206 responses and after a quite a struggle i can have the same end result for Safari in macOSX, and i convert the videos like so

  


  ffmpeg -i test.gif -qmin 0 -qmax 18  -vcodec prores_ks -q:v 64 -b:v 1400K  -pix_fmt yuva444p10le -profile:v 4444 -an -sn -metadata title="test mov" test.mov

  


  I put in the url address bar the that serves the video with stream and the video plays with transparency all good.

  


  Now on Safari in iOS the video just does not play, it is loaded with the same endpoint and other videos without transparency also work, serving from the same stream endpoint.

  


  Does anyone knows of a solution to encode a video with transparency that plays on all apple devices ?

  


  I also gave handbrake a try without success, actually could not even get the transparency right with handbrake.

  


• FLVTool2 on github

  10 avril 2010, par admin — FLVTool2

  During the last years I didn’t gave FLVTool2 the love it deserved. But the community was very productive and came up with a lot of bug reports, patches and suggestions. I didn’t find the time to get all that good feedback into FLVTool2. Now I put the FLVTool2 source code on github so that you (...)