Category Archives: Technology

AWS Adventures, Part 3 – HA Wowza Live HLS

AWS, Technology

For a number of years, we have streamed HLS video via CloudFront, using a Wowza Streaming Engine server to convert our RTMP streams to HLS on the fly. CloudFront provides almost infinite scalability for the HLS stream, since the static chunk files are highly cacheable.

For high availability purposes, we want to use two independent WSE servers in two AWS availability zones. But this has been problematic. The two servers are never 100% in sync with their HLS chunking of the incoming live stream. This can cause the client to get a bad response to a request, thereby dropping the live stream.

After a lot of experimentation, I have come up with a way to assemble a multi-AZ, high availability cluster of WSE servers that can reliably stream HLS video from an incoming RTMP stream.

Continue reading AWS Adventures, Part 3 – HA Wowza Live HLS →

AWS Adventures, part 2 – high-availability FTP service

AWS, Linux, Technology

In our AWS migration, we found it necessary to run an FTP server. Yeah, I know — “FTP? In the 20-teens?”. Look, I get it — nobody wants to run an FTP server in this day and age. But it is still a convenient way for partner companies to transfer data to us via automation. This isn’t highly sensitive data; our main concern is keeping the FTP server isolated from our other services so that any vulnerabilities there don’t propagate to more critical systems.

At any rate, we found it surprisingly challenging to build a highly available FTP service in AWS.

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Benchmarking QuickSync on Broadwell and Skylake

Linux

We’re in the process of building out some new Linux-based video encoders, and we want to output to a LOT of different destinations: live streams, archived versions on disk, high-quality versions for future editing, JPEG stills, etc.

QuickSync is a great way to get more out of our processors by offloading the encoding to the GPU. To figure out what architecture to invest in, we ran some tests with a Broadwell processor, the Core i7 5775C (3.3 GHz), and a Skylake processor, the Core i7-6700K (4.0 GHz).

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Building FFMPEG with support for Decklink Capture and QuickSync encoding (Skylake edition)

Linux, Technology

NOTE: this document covers Intel’s Media Server Studio 2017. If you want to use Media Server Studio 2016 with an older processor, see this article.

With the release of Media Server Studio 2017, Intel provides Linux with the ability to leverage QuickSync on Skylake processors. This is a welcome development, as Skylake’s graphics capabilities are significantly better than previous generations of Core processors.

This article outlines how we built ffmpeg to capture video from a Blackmagic Design DeckLink mini and encode it using Intel’s QuickSync technology (h264_qsv).

Continue reading Building FFMPEG with support for Decklink Capture and QuickSync encoding (Skylake edition) →

Building FFMPEG with support for DeckLink capture and h264_qsv encoding

Linux

NOTE: this document covers Intel’s Media Server Studio 2016. If you want to use Media Server Studio 2017 with a Skylake processor, see this article.

ffmpeg has come a long way since the pre-1.0 days. With its elaborate system of routing filter outputs, its ability to capture video from video cards, and support for GPU-based encoding, it has become quite the powerhouse in the video world.

This article outlines how we built ffmpeg to capture video from a Blackmagic Design DeckLink mini and encode it using Intel’s QuickSync technology (h264_qsv).

Continue reading Building FFMPEG with support for DeckLink capture and h264_qsv encoding →

Galaxy S7 default config not using full display resolution

Technology

I recently discovered that my Galaxy S7 Edge was reporting its display resolution as 640dpi, when I expected it to be approximately 534dpi. What’s the big deal, you ask? Well, it’s causing dynamically sized elements on screen to be approximately 17% bigger than they were intended to be drawn. Some users might like this, as it will make elements just a little easier to tap on. But others might not like it, because you can’t display as much information on the screen.

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