Video Sex


I've got a new video recorder. Well, actually I've got someone else's old video recorder. My parents own some small properties around the town, which they rent out through an agency. One of the tenants, after five years of uneventful lodging, has abruptly moved out - leaving behind his rather nice 3-piece suite and an old VCR. I've got the VCR.

I've also got several hundred VHS tapes, sitting in storage boxes, unwatched for years. Some of the recorded programmes are worth making digital copies of, before I finally get around to dumping the tapes. So, what's the best way to digitise VHS?

Warning: Slightly Technical Bit - skip if you don't know about video compression

The best way is to do it is to play the programmes into my computer's capture card, and capture them uncompressed, before applying algorithms to clean up the sound, reduce colour-bleed, interlacing artifacts, tracking wobble, noise and any other imperfections I can think of, while compressing the file to MPEG-4 at full resolution at the highest quality the DivX algorithm can offer. Unfortunately this takes roughly 1GB of disk space per minute to capture, and 24 hours or more to reprocess each programme.

A reasonable alternative looks like this:
* Set the capture card to record at full screen resolution and full framerate. If your tapes use NTSC, that means 640x480 pixels, at 29.97 frames per second. If you're using PAL like me, it's 704x576 at 25fps. Actually, it's 720x576, but the rightmost 16 pixels are usually unused. Which means, sometimes, they will be. But I'm assuming not.

* Although your card is capturing at fullscreen resolution, you're setting the DivX (or XviD, or even WMV) codec to encode at 320x240 for NTSC and 352x288 for PAL, using the bicubic resize method of your choice, and deinterlacing the image. The codec is working in real time, so you can't use bidirectional encoding, and your computer probably can't handle GMC, quarter-pixeling, or the settings for best quality and/or highest compression. I recommend keyframe settings of 125 for maximum interval, and 33% for threshold. If the video is jerky or noisy, increase to 50%.

What you're doing is capturing at TV resolution, then reducing it back down to VHS resolution - halving it both horizontally and vertically. I reckon a kbps setting of 1000 is more than enough, and 750 is okay. As regards noise shaping and psychovisual enhancements, the former might improve the signal somewhat, but I doubt they can be applied consistently in realtime without dropping frames.

* Record in real time, with CD quality audio. If you have the time and inclination, export the audio as WAV from VirtualDub, clean it up in Audition or Soundforge, and import the result back into VirtualDub. Edit out adverts and whatever bits you don't want, then compress the audio to MP3.


End of Slightly Technical Bit

Of course, most of the tapes are unhelpfully (or illegibly) marked, so I don't know what's on them till I play them.

Strict Machines want to make a video to go with one of their songs. Getting the raw footage for this involves using carpet tape to fix my old camera to the handlebars of a bike, and riding around town at day and night, filming. And filming the band play in a dark basement with flashing lights. And generally pointing the camera at anything that looks interesting, especially if it's lit up at night. Camera shake is a good thing for this project.

An alternative method of filming involves taping the camera to the side of one of our heads, and going for a long walk. This is not such a popular alternative.

I had sex tonight. I found it quite pleasant, and my partner seemed to be enjoying it immensely. Halfway through I found myself thinking, "It's okay, but a bit dull - I'd rather be doing something else, like, oh I don't know, finding a nice man and having sex with him. Oh, that's what I'm doing isn't it. Ah."

4 comments:

  1. Congrats on the sex, not on the thought... (Lol!)
    The idea of finding/meeting the next one can become quite obsessive, can it not?... And cruising demands so much time... I prefer to wait for «being cruised»; it's so much more comfortable...

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  2. Indeed. A lot of time and energy spent on finding something, then being unsure why you wanted it.

    And then doing it again. Very strange.

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  3. First of all a technical piece that I've only just woken up from - Capture from VHS then translate at half the size onto CD at VHS resolution - huh?

    Then a bit about the goings on of 'The Strict Machines' which is always entertaining, especially as the guitarist seems so oddly strange he often leaves Kap's own strange oddness in the dust ... but then, then: TOO MUCH INFORMATION! about cruising, which I always assumed happened on the Norfolk Broads, but obviously doesn't, and that thing they do to make babies - or not.

    Must find my meds.

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  4. Video is confusing stuff. So many formats, and so many considerations when translating between them. Someday I'll write about a convoluted process called Inverse Telecine.

    Paul the guitarist is kind of my opposite. He's always extremely intense about everything, and never thinks through the technical details of what he wants to do. I'm pretty laid back, and get creative usually as part of solving technical problems.

    One paragraph about cruising is too much information? In capitals? I don't know much about Norfolk Broads - or indeed any kind of broad. I don't meet many of them while cruising.

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