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Review: The SiliconDust HDHomerun Connect Quatro!

April 7, 2018: Please take a look at the follow-up to this review.

Koherence’s projects have long been powered by SiliconDust HDHomerun tuners. At present 13 HDHR4s are feeding the three production Entangles, and a venerable HDHR Rev 2 handles other sundry tasks. The RF and power supply cabling has started to become quite…entangling…so the announcement of the four-tuner HDHomerun Connect Quatro was received with much anticipation. As soon as a (not quite local) Best Buy got it in stock, I was off to get one for evaluation! Continue reading “Review: The SiliconDust HDHomerun Connect Quatro!”

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The Project Entangle Wishlist (i.e. why write a DVR?)

So I’ve been getting this question a lot over the past several months: Why Project Entangle? Why would I go about writing a DVR?

On the surface it’s easy to think I’m crazy (in addition to being inkoherent). After all, there’s the Tablo OTA DVR (in fact I’ve had one since the Indiegogo days, although it’s been gathering dust for a couple years). Plex has added DVR support. And the fine folk at SiliconDust now have a DVR for their HDHomerun devices too. And there’s TiVo. Having been affiliated with them for close to two decades, I have a variety of them from Series2s to Roamios. Continue reading “The Project Entangle Wishlist (i.e. why write a DVR?)”

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Speeding Up Slow Sums – Faster BSD Checksums

I recently made some changes to the Entangle archive that required a good majority of the archive to be checksum reverified. That’s about 200 TB worth of checksums. Even with six systems running parallel, and RAIDs hitting 600 MB/s, it still takes a while.

One thing I noticed was that the I/O rate while the sums were being performed was ~210 MB/s. A respectable speed, but cp’ing a file from the RAID to to /dev/null results in ~600 MB/s. So either my CPU was too slow or the ‘sum’ operation wasn’t as efficient as it could be. Continue reading “Speeding Up Slow Sums – Faster BSD Checksums”

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Project Entangle

Project Entangle is Koherence’s internal platform for developing various media technologies. It began as a test bed for investigating how TiVo-style trick modes could be implemented using HTTP Live Streaming. Since then Project Entangle has blossomed into a collection of platforms.

The Entangle DVR platform supporting in-home and out-of-home playback is currently being alpha tested, with users watching shows on iPhones, iPads and AppleTVs. Another platform variant powers the SFBayATSC ATSC broadcast monitoring system. Continue reading “Project Entangle”

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Just What Is High Definition?

I recently read a newsgroup thread that started with someone asking just what high definition was. The thread wound in some surprising ways, with individuals asserting, among other things, that anything 16:9 was high definition and that 480i digital content was high definition (while presumably 480i analog was not). I suspect most of you wouldn’t agree. After all, we all know 720p and 1080i are HD while anything less is SD, right? Well things aren’t quite so clear cut.

Continue reading “Just What Is High Definition?”