EPG Data Collection isn't Cable Carriage

(May 2017) I've heard that a TV listings data aggregator is offering to collect schedules from PEG stations for $100 per month. People may think that this is how they get into cable interactive electronic program guides (IPG or EPG). But unless your cable company contacts you to arrange it, that's probably not what's happening.

As I explained in my talk at the Alliance for Community Media's Boston conference in 2016 (see slides on this site), you are already publishing your schedule to the world, for free. See the links slide showing how four popular playout servers have built-in online schedules.

Unless local cable EPGs are carrying your listings, only the data aggregators benefit from your data because they can have it on their websites, too. That's not a reason for a PEG station to spend money. But do spend it to schedule for two to four weeks ahead. You will need that when you do get into the EPG. Use TBDs as needed; you can always update with more information as you get it.

Bootable USB flash drives

While installing pfsense on an Intel mini-ITX board, the "memstick" version failed to boot from two of three different brands of USB flash drives.  Even with the latest BIOS, booting failed with messages like "bootable device has not been detected".

I examined the drives' boot sectors with Microsoft's secinspect.exe. "EB" was the first byte on the working drive and "33" was the first byte on both failing drives. If I understand correctly, when "EB" is the first byte, it's a "Boot Sector" for floppy disks, while if "33" is the first byte, it's a "Master Boot Record" for hard disks.

I used HPUSBDisk.exe to format the drives as DOS Startup Disks using files from Win98Boot.zip, then used the normal dd procedure to transfer the memstick image. All three drives can now boot the pfsense installation code.

Tightrope components

I figured this out while setting up a new channel on an existing system. Tightrope confirmed it for me.

FrontDoor -> Cablecast Server -> Cablecast Channel -> Servers (e.g. SX Player)

FrontDoor -> Carousel  (resident on Cablecast server if shared with a station, or on Carousel server if signage only) -> Carousel Channel -> Carousel Player -> Carousel Display Engine

Deinterlacing archival video

I've been surprised by the poor quality of some digitized archival footage appearing in recent TV documentaries. You can see the problem where there are horizontal fringe effects in rapidly moving objects. Those artifacts are not in the original material and they are easily prevented. You need to deinterlace old TV recordings when converting them to a compressed MPEG format.

If you are using Handbrake on a Mac computer, the default setting seems to be no deinterlacing (at least that's what I found in my setup), but Handbrake actually contains some powerful tools. See the explanation at https://trac.handbrake.fr/wiki/DeinterlacingGuide

To make sure you have it working, select Window:Picture Settings, then Filters. Choose Decomb (Handbrake's improvement over generic Deinterlace) and select Decomb: Default.

That allowed me to make this:                                           into this:

Explanation: The images are closeups from two conversions of video showing a logo that was being both panned and zoomed, so there was a lot of motion in the recording. With no motion, the two images would be the same. Interlaced scanning in the North American system means the camera captures alternate lines of a frame 1/60 second (16ms) apart. That can be a long time when things are moving fast. Stacking both fields on top of each other to merge the alternating lines, instead of showing them in proper time sequence, looks bad. That's what the left side shows.

When a camera scans progressively, there are no "alternate" lines; every line in a frame is captured less than 1/40000 second (25 us) after its neighbor. This is why sports networks favor the higher temporal resolution of the 720p system over the higher spacial resolution of 1080i for high def. But older archival video is usually recorded in the analog version of 480i, and it must be deinterlaced for a decent digital conversion. Deinterlacing (or Handbrake's "decombing") uses knowledge of the recording process to reassemble the sequence of frames with moving elements in their proper places, as seen on the right.

Sleep Proxy and IP Address Conflicts

I reported this to Apple about their "Resolving IP address conflicts" help page, using the page's Feedback form.

I've repeatedly seen the message "Another device is using this address" when I wake up my MacBook. I had been letting my pfsense firewall issue a DHCP address from the range below 99. Considering the possibility that some random device was accidentally issued the same address during some overlap between sleep times and lease intervals (though I couldn't find it in the arp tables on either the laptop or firewall), I changed the laptop to be a static address in a different range. The message appeared again, with the new address! So this wasn't some coincidence. The newest item in my network is a Time Capsule, and I've been told by a network guru friend that it has a subtle, well-hidden feature called "Sleep Proxy" which is supposed to make life easier.

I spoke to a third-level tech at AppleCare but she unfortunately didn't know anything about Sleep Proxy on Time Capsule.

I suggested to Apple that they:
1) Fix their IP stack to test for a Sleep Proxy event instead of alarming the user about a nasty-sounding, obscure, and actually benign event on the network,
2) Add an explanation of the possibility of Sleep Proxy as a reason for the message.

Originally, I didn't know how to turn off the feature on the Time Capsule, and I didn't know what other device or process is trying to reach the MacBook while it's asleep, which is when the Sleep Proxy would theoretically provide its service. (Actually, I was suspicious that it was the Time Capsule itself looking for its backup client, i.e. the MacBook.) I did eventually find out how to disable it from Apple's article HT3774: Turn off the Mac's Energy Saver preference "Wake for WiFi network access" which registers the Mac with Bonjour Sleep Proxy. I haven't had the message once since I turned that off.

Update 2014-10-05: A complete discussion from 2009-2010 is on Apple's site:  https://discussions.apple.com/thread/2160614