Recherche avancée

Sur d’autres sites (8770)

• Why doesn't the lame mp3 codec (libmp3lame) create XingHeaders ?

  5 novembre 2012, par user784637

  I downloaded a video from youtube whose audio was encoded in aac and transcoded it to an mp3 using the libmp3lame codec.

  $ ffmpeg -i video.mp4 -vn -acodec libmp3lame -- test.mp3

  Now when I try to write id3 tags to it using the taglib example tagwriter I get the following warning :

  $ ./testwriter -t 'stuff' test.mp3
  
  TagLib: MPEG::XingHeader::parse() -- Xing header doesn't contain the total stream size.

  The id3 tags are written and display correctly, but the lack of the XingHeaders causes older players to loop the song several times.

  Why doesn't the lame mp3 codec create XingHeaders ? How do I create XingHeaders ?

• Batch convert MP3 and static image to AVI with FFMPEG

  8 décembre 2013, par user3027136

  I'm tired of searching for this problem. I have found 2 solutions here, but both work only partially.
  What I want to do is to convert all the MP3 inside a folder (if possible subfolders, too) to avi or anything else accepted by Youtube. I have created 2 .bat that should do this (according to the other threads here). They don't, one of them creates the avi without the image (black) and the other seems to capture the screen.
  Here they are.
  If you know about ffmpeg please point me to the right direction. Thank you.

  This one uses mp3info.exe - to be honest I have no idea what mp3info does, I just guess it finds the lenght of the song to be mathed later with the length of the video.

  @echo off
  
  for %%a in (*.mp3) do (
  
  for /f "delims=" %%b in ('mp3info.exe -p %%S "%%a"') do (
  
  ffmpeg -i "%%a" -loop 1 -r 1 -i "cover.jpg" -acodec copy "%%~na.mp4" -t %%b
  
  )
  
  )

  This seems more simple, runs faster but captures the screenshot and ignores the cover.jpg file.

  @echo off
  
  for %%A IN (*.mp3) DO ffmpeg -i "%%A" -i "cover.jpg" "%%A.mpg"
  
  done

  mp2info.exe, cover.jpeg and the .bat scripts are in the same folder with the .mp3 files.

• live preview of video processing in android app

  19 septembre 2016, par Ashish Mathur

  I’m building a video editing app and currently I am using ffmpeg for encoding and decoding process (my app can easily do the tasks where live preview is not required like reverse a video or apply filters like B/W or pick specific frames in video and some audio tasks etc)
  but Problem is that if user want to adjust the brightness or contrast of the video they require live preview of the video but that is not supported by ffmpeg ffmpeg requires to encode the video before the preview
  so my question is how can I achieve live preview with ffmpeg

  Thanks in advance (sorry for grammar related problems in the question)