Video Graininess What am I doing wrong??

Discussion in 'Digital Video' started by MikeT125, Jun 11, 2009.

  1. MikeT125 macrumors regular

    Joined:
    May 16, 2007
    #1
    I am editing a movie for content and when I get to the final product I have two problems. The first is that the picture is grainy and the second is the audio loses it's 5.1 surround sound and only comes out in stereo. I'll give you my process and maybe you can tell me where my losses are coming from.

    1. I extract the original movie using mac the ripper (never saw any losses at this point.

    2. I use Handbrake to turn it into an MPEG4 with the settings on constant quality and 100%.

    3. I then use MPEG-Streamclip to convert the video into DV for use in iMovie.

    4. I edit the movie in iMovie and then export it directly into iDVD

    5. In iDVD I then have something like 7.5GB of information so I need to use "Professional quality to compress it onto a single layer DVD.

    I am not sure which process I lose video quality in and which one loses the 5.1. as far as I know the only video iMovie can accept is in a .DV format. Since the MPEG-Streamclip can only accept MPEG4 files (without the add-on from Apple). One of the possible ideas I had to see if it was the IDVD compression was to see if I could export it from iMovie and then compress it with TOAST and see if that was the problem. What are your thoughts??

    MY final output will br viewed on a TV through a DVD player
     
  2. cpcarrot macrumors member

    Joined:
    Jan 24, 2008
    #2
    What is your original source for the material?

    Skipping ahead though, in simple terms every single stage you have mentioned means you lose quality of video, and chances are you lost the 5.1 encoding at stage 1, and would probably lose it at stages 2-5 if you didn't.
     
  3. CaptainChunk macrumors 68020

    CaptainChunk

    Joined:
    Apr 16, 2008
    Location:
    Tempe, AZ
    #3
    And therein lies your problem. You WILL lose quality converting MPEG-2 from a DVD to MPEG-4. No matter what. You're losing quality right off the bat in Handbrake, which only gets worse you compress back to MPEG-2 from DV.

    Your best results are going to come from having Apple's MPEG-2 components so you can eliminate encoding to MEPG-4 altogether.

    As for your audio problems, preserving 5.1 might be an exercise in futility.

    Handbrake can pass AC3 (Dolby 5.1) through in an .mp4 container, but that will only be useful for playing back on a computer with VLC and 5.1 speakers.

    In order to preserve the surround sound for editing, the AC3 audio would be to be demuxed from the DVD into an uncompressed format like AIFF with 6 separate channels and then encoded back to AC3 when you're finished editing. MPEG Streamclip can demux to AIFF, but only in stereo, so it'll force a downmix.

    Outside of Windows, I'm not sure if there's anything out there capable of splitting an AC3 file into 6 discrete audio tracks, which is what you would need. Perhaps someone else here has an idea...

    Also, you would need to way to encode back to AC3 5.1 when you're all done. I do this with Apple Compressor (included with Final Cut Studio), but I'm unaware of free software that would do this. AFAIK, iDVD will only do stereo AC3 when it builds DVDs.
     
  4. lostless macrumors 6502

    Joined:
    Oct 22, 2005
    #4
    Its grainy because its been through 5 stages of compression (DV is compressed, even if its just a tiny bit.) Every stage adds more digital compression noise. For 1, skip the Handbrake part. H.264/Mpeg4 while quite good at compression, should not be used in between Mpeg 2 (DVD format) and DV. For minimal loss, you should go from the DVD source to DV. Edit and then recompress back to DVD. I've done this and the loss is not that bad, but is noticeable if you looked at the original source. MpegStreamClip can export mpeg 2 to DV if you buy apples Mpeg2 component. Well worth the twenty buck investment.
    If your source is a movie, the final result may come out choppy since imovie only handles 30FPS and Film DVDs are at 24FPS. So going to DV adds 4 extra frames per second. The extra frames are just a repeat or every 4th frame. So it goes 1 2 3 4 4 5 6 7 8 8 ect... IDVD only encodes at 30FPS even with a 24FPS source, to make matters worse.

    If its a home movie (judging that you want to preserve the 5.1 that it is not) IMovie deinterlaces to 30 FPS loosing half the motion information. Home movies and other media use interlacing with 2 frames in each frame. So it runs at 30FPS but has 2 frames in each making the final outcome 60FPS.

    As for the 5.1, its lost using I movie and Idvd. They both only support stereo, which is not bad with a good DPLII decoder to recreate the 5.1.

    Good luck.
     
  5. MikeT125 thread starter macrumors regular

    Joined:
    May 16, 2007
    #5
    I am new at this so that is why I listed the steps I am using because I am sure there is a better way to do it.

    From what I am hearing, if I go from the DVD straight into DV, which MPEGstreamclip will do with the apple add on, then iMovie to iDVD to the DVD that should be better, correct?

    What is the CORRECT way to do it so that it looks as close to the original as possible?
     
  6. CaptainChunk macrumors 68020

    CaptainChunk

    Joined:
    Apr 16, 2008
    Location:
    Tempe, AZ
    #6
    With the software you have at your disposal and the $20 MPEG-2 component, yes, that would be the best way.
     
  7. MikeT125 thread starter macrumors regular

    Joined:
    May 16, 2007
    #7
    I think I'll get that $20 component. If I were to take a step up (just a little) what would be the next thing different, process or software, I should do or get?
     
  8. giffut macrumors 6502

    Joined:
    Apr 28, 2003
    Location:
    Germany
    #8
    You ...

    ... would get a real DVD authoring software - like a used DVD Studio Pro package on eBay, or similar. In that case you don´t need no encoding and just import the native MPEG2 files. You can use MPEG streamclip for rough cutting or transcoding (Apple Pro Res for best quality transcode) for detailed, effect based cutting with Final Cut Pro.
     
  9. CaptainChunk macrumors 68020

    CaptainChunk

    Joined:
    Apr 16, 2008
    Location:
    Tempe, AZ
    #9
    The only way to get the current version of DVD Studio Pro is to buy Final Cut Studio. DVD Studio Pro hasn't been available as a standalone product since Version 3 in 2004, I believe.
     
  10. giffut macrumors 6502

    Joined:
    Apr 28, 2003
    Location:
    Germany
    #10
    Yes, ...

    .... that´s right, but also the reason to go out and buy used. Even DVD Studio 2 is still fine for DVD authoring - and besides fancy themes much more powerfull than even the most recent iMovie; you could get the DVD Studio Pro 3 upgrade for cheap later on. You even might be able to grab Final Cut Studio. If your budget is constrained, but you need more muscle, well ...
     
  11. LethalWolfe macrumors G3

    LethalWolfe

    Joined:
    Jan 11, 2002
    Location:
    Los Angeles
    #11
    Kinda, sorta, not really. ;)

    Interlaced NTSC video runs at 30 frames per second (technically 29.97fps). Each frame is made up of two fields (not two frames) that are recorded alternately every 1/60 of a second. 60 fields = 30 frames and iMovie doesn't deinterlace anything.


    Lethal
     

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