Hein (fub) wrote,
Hein
fub

  • Mood:

VHS -> DVD and other musings

Today, we transported exar's new computer from the store to his house. It's a really nice-looking machine with  quite decent specs -- only too bad that they forgot the speaker system and the printer... We helped unpack and set up the hardware, just to verify it all worked. While we were unpacking things, exar ran a UTP-cable from the ADSL router across the hall to the computer. You gotta love WinXP for the way it handles networking: just plug it in and you're online!

Now I'm experimenting with the video I capture earlier. I want to put it on a DVD, but first I need/want to cut out the commercials. At first I used the MPEG-tools in TMPGenc, but it turned out that the keyframes were not at the right positions in the file to make a clean cut...

MPEG is a video compression method. There are various versions of the MPEG standard: VideoCD uses MPEG1, DVD uses MPEG2 and DivX is MPEG4.
MPEG stores some frames as complete pictures (those are the keyframes). For the following frames, it stores the changes between the current frame and the preceding frame. With things like scene detections, the encoding software determines when the changes are too big -- it will insert a keyframe at that spot, to keep the file size down.
If you want to cut up an MPEG-file, you can only cut from keyframe to keyframe -- if you cut a non-keyframe, all following frames don't know what the changes are. In this particular case, the TV station's intro faded to black, while the intro of the movie faded in from black. Here, the scene detection went awry (because there were too little changes between the frames. And that meant I got the TV station's intro too...
Of course, that is highly undesirable. And of course, I felt a need to bend the available technology to my will. I'm... odd that way. Some googling learned me that I could select the keyframe manually in TMPGenc. This means I have to re-encode all of the MPEG, but it's a good way to put those hyperthreaded 3.0Ghz to use! Unfortunately, when I put the latest version of TMPGenc to work, it didn't like the file. It crashed. No matter what I did, it kept crashing.

This pissed me off. I mean, I can take a few crashes now and then, but not when I am exerting extreme sentient force to get something done. Some more googling revealed that someone who had the same problem, solved it by using an older version of TMPGenc. Some more googling turned up the earlier version he mentioned (it turned out to be amazingly hard to get older versions of TMPGenc). I installed that, and it all worked...
Right now, I'm running the automatic keyframe detection of TMPGenc. Tomorrow, I should have an MPEG file that's keyframed correctly, so that I can cut it up in the pieces I want.

This is turning out to be more work than I bargained for, but I guess I'll get things done much quicker when I have developed a routine for it.

Oh, and rupertdaily, if you want to see a sample piece of digitised VHS, just give me a holler!
Subscribe

  • Expanding my network

    I haven’t been posting here that much — partly because I don’t have much to say. But I haven’t been off the internet, of…

  • Things that happened this week

    A power interruption. We had gotten a letter from the company that manages the power lines that they’d be working on the infrastructure on…

  • The Forest Shrine released!

    In the early stages of 2020, I released my scenario The Secret of Cedar Peak, a scenario for fifth edition Dungeons & Dragons. I had a sequel…

  • Post a new comment

    Error

    Anonymous comments are disabled in this journal

    default userpic

    Your reply will be screened

    Your IP address will be recorded 

  • 11 comments

  • Expanding my network

    I haven’t been posting here that much — partly because I don’t have much to say. But I haven’t been off the internet, of…

  • Things that happened this week

    A power interruption. We had gotten a letter from the company that manages the power lines that they’d be working on the infrastructure on…

  • The Forest Shrine released!

    In the early stages of 2020, I released my scenario The Secret of Cedar Peak, a scenario for fifth edition Dungeons & Dragons. I had a sequel…