Results 1 to 6 of 6

Thread: mov to avi conversion

  1. #1
    Join Date
    Aug 2008
    Beans
    32

    mov to avi conversion

    Can someone tell me what's going on when I run these two commands. I am pulling a video off of my iPhone and then converting it to avi. The video is rotated so I rotate it with the second command.

    My question is why is the file size shrinking after the rotation? I read through the documentation for the commands but nothing is jumping out at me. I'm guessing it has something to do with the codecs used with these commands. Any help or explanation would be helpful. Thanks.

    Code:
    ffmpeg -i chase_eating_noodles.mov -sameq -vcodec mpeg4 -acodec libmp3lame chase_eating_noodles.avi
    
    mencoder -of avi -oac mp3lame -ovc lavc -vf rotate=1 -o chase_eating_noodles.avi cen.avi

  2. #2
    Join Date
    Jul 2006
    Location
    Lancashire
    Beans
    Hidden!
    Distro
    Ubuntu 11.04 Natty Narwhal

    Re: mov to avi conversion

    Quote Originally Posted by stevebu56 View Post
    My question is why is the file size shrinking after the rotation?
    Hi
    It's probably because MEncoder is using a lower bitrate than the original iPhone video.

    Can you show details about that original iPhone video.
    Paste the result from a command like this:-
    Code:
    ffprobe chase_eating_noodles.mov

  3. #3
    Join Date
    Nov 2011
    Location
    bod
    Beans
    78

    Re: mov to avi conversion

    If you use ffmpeg also to rotate, you should have no problems with quality caused by mencoder.

    http://phayz.wordpress.com/2011/10/28/howto-rotate-a-video-using-ffmpeg/

    Add this option to the command (before the output file)
    Code:
     -vf "transpose=1"
    or "transpose=2" if you want to rotate the other way.

    Nota bene: This only works with rather new versions of ffmpeg compiled with filters, for example version 0.8-4:0.8-1ubuntu2, that is obtained via
    Code:
    sudo apt-get install ffmpeg
    in Precise beta (Ubuntu 12.04). Actually, it is recommended to use avconv instead, which has the same syntax, so I guess it is built from the same source code, and further developed.
    Last edited by pixiq; March 22nd, 2012 at 03:09 AM. Reason: typing error

  4. #4
    Join Date
    Aug 2008
    Beans
    32

    Re: mov to avi conversion

    @ron999 Here's the info from ffprobe for the mov file and the avi file respectively.

    Code:
    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'cen.mov':
      Metadata:
        major_brand     : qt  
        minor_version   : 0
        compatible_brands: qt  
        creation_time   : 2012-03-21 20:27:18
        encoder         : 5.1
        encoder-eng     : 5.1
        date            : 2012-03-17T09:36:08-0500
        date-eng        : 2012-03-17T09:36:08-0500
      Duration: 00:00:49.78, start: 0.039955, bitrate: 769 kb/s
        Stream #0.0(und): Audio: aac, 44100 Hz, mono, s16, 62 kb/s
        Metadata:
          creation_time   : 2012-03-21 20:27:18
        Stream #0.1(und): Video: h264 (Main), yuv420p, 480x272, 704 kb/s, 30 fps, 30 tbr, 600 tbn, 1200 tbc
        Metadata:
          creation_time   : 2012-03-21 20:27:18
    
    Input #0, avi, from 'cen_rotated.avi':
      Metadata:
        encoder         : MEncoder SVN-r33713-4.6.1
      Duration: 00:00:49.76, start: 0.000000, bitrate: 912 kb/s
        Stream #0.0: Video: mpeg4, yuv420p, 272x480 [PAR 1:1 DAR 17:30], 30 tbr, 30 tbn, 30 tbc
        Stream #0.1: Audio: mp3, 44100 Hz, mono, s16, 102 kb/s

  5. #5
    Join Date
    Aug 2008
    Beans
    32

    Re: mov to avi conversion

    @pixiq I was able to add the transpose option and that works fine with one less command to remember when I'm editing. Thanks.

  6. #6
    Join Date
    Nov 2011
    Location
    bod
    Beans
    78

    Re: mov to avi conversion

    Quote Originally Posted by stevebu56 View Post
    @pixiq I was able to add the transpose option and that works fine with one less command to remember when I'm editing. Thanks.
    I'm glad it works for you too

    When you feel like it, please mark this thread as SOLVED clicking on Thread Tools at the top of this page!

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •