Snail#

When converting recorded ATSC 1.0 (over-the-air) broadcasts to video DVD format using devede, I've noticed the audio/video sync ends up a little off.

Re-encoding the audio seems to fix this:

ffmpeg -i input.mts -c:v copy -c:a aac -ac 2 output.mkv

This keeps the video data intact, and just re-encodes the audio (as stereo, not the original surround sound).

These sorts of broadcasts usually have an alternate audio track as well - you could use some -map arguments to pick the track(s) you want, but I didn't bother with that this time around.

After doing this, I can put the resulting file into devede :)

If that doesn't work, here's a script that will convert the closed captions to subtitles and re-encode the video. Sometimes this can be necessary - an over-the-air data stream is sometimes missing some data that automated scripts can run into problems with.

#!/bin/sh
set -e
for i in $*; do
	o="$(basename $i)"
	m="$o.mp4"
	if ! [ -f "$m" ];then
		chmod +r "$i"
		ffmpeg -i "$i" -c:a copy -c:v copy "$o"
		ccextractor "$o" -in=ts -out=srt
		ffmpeg -i "$o" -c:a aac -ac 2 -c:v libx264 -preset veryfast "$m"
		rm "$o"
	fi
done

I've got a Dell Dimension 4700. It's a 32-bit PC from the mid-2000s, and it's just barely new enough to have a PCI Express slot, which I used to add USB 3 ports, including a type-C, on a front panel (mostly because I thought it was funny).

The only actual work I do on this computer is writing, and the only way I can concentrate on writing is if my computer doesn't let me do anything else, and doesn't show anything else on the screen. That's why I do all my writing in Word 5.5 for DOS. For editing, I usually like to use Word 97 (with doswrd32.cnv), then export to HTML and copy to a thumbdrive.

I'd also like a Debian installation on there, just in case it comes in handy for some random project, but I don't want to commit to not touching it. There's a good chance I'm going to want to overwrite the installation at some point in the not-too-distant future - either by installing over it (maybe with a newer version), or removing it to make more space in my Windows partition for storing some big ol' files - and I don't want that to break my bootloader.

So I need to be able to:

• Boot into FreeDOS
  
• Boot into Windows (this computer's got a Windows 7 license, so that's what I'm using)
  
• Boot into Debian on the rare occasion I need it
• Delete the Debian partition without breaking the ability to boot into the other environments

In a normal triple-boot, you'd probably do something like this:

• Install Windows 7
  
• Install FreeDOS
• Install Debian using the rest of the available space

In this situation, Debian installs GRUB 2, which allows you to boot Windows 7 or FreeDOS instead.

But I don't want to commit to my Debian installation - I'd like to be able to overwrite or remove it, and still boot the other two operating systems on the drive. So what I want is a system that asks if I want Windows 7 or FreeDOS, then gives me a sneaky way to boot to Debian instead if I'd like. Turns out there's a setup that works really well in this very specific situation, and doesn't need any external boot disks. I'll walk through it below.

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