Encoding

I discuss the bandwidth savings delivered by VP9 and HEVC over H264 in my course Streaming Media 101: Technical Onboarding for Streaming Media Professionals. I wanted to illustrate this with my own tests, so I used FFmpeg to encode H.264, HEVC, and VP9 output using about 25 short test files. This felt like a good time to discuss the difference …

If you’re onboarding new hires in streaming media-related positions, you now have an affordable option for providing and monitoring that streaming-specific training. If you’re a professional seeking to upgrade your skills and gain accreditation, you have that option as well.  Over the last few years, streaming media has become critical for entertainment and communications, with the quarantines necessitated by Covid-19 …

We’re all aware of the sudden need to reduce streaming bandwidth to alleviate congestion. MediaMelon’s SmartPlay/QBR is a very viable option for this that was recently adopted by Brazilian OTT producer Telecine. I reviewed MediaMelon’s QBR technology for Streaming Media Magazine back in 2017. I called it a “server-side, per-title delivery mechanism.” Unlike traditional per-title technologies that re-encode your files …

If you’re comparing codecs with video quality metrics, you should consider tuning for that metric. However, x264 and x265 don’t have a VMAF tuning option. According to my analysis, it appears that tuning for PSNR is the best option and one you should strongly consider. When working with VP9, there’s an additional complication; tuning for PSNR doesn’t appear to work.  …

Producing the chart above involved encoding 35 files using 5 different presets and then recording start and stop times. Since the files were about 20-seconds long, seconds were important. I’m sure a smarter compressionist than I could write a Python script to harvest the start and stop times but I do it by hand, which is complicated because Windows Explorer …

This is a long post only of interest to those attempting to optimize their VP9 encodes. The three key takeaways are 1) use the command script shown on the bottom of the page, 2) a speed setting of 2 offers the optimal quality/performance tradeoff, and 3) the row-mt setting improves performance significantly with zero quality loss when multiple unused cores …

The Common Media Application Format (CMAF) is supposed to be the Holy Grail of streaming; one set of files that you can deliver to multiple output points. How well does it work today? This 3:47 video shows you. I started by creating CMAF output in AWS Elemental MediaConvert. Why? Because they supply useful templates, have an easy to use UI, …

In a blog full of wonky compression articles, this could be the wonkiest article of all. If you’re not using capped CRF encoding, or considering the same, it’s almost certainly not of interest. If you are using capped CRF encoding (for constant rate factor), however, you almost certainly will find it interesting and perhaps even illuminating. A quick background note. …

It’s always good to review which articles readers found valuable over the past year to help focus on producing similar content in the future. By publishing the top ten, hopefully, those reading this article will see some articles they might find useful. So, without further ado, here were the top ten articles from the Streaming Learning Center blog in 2019. …

This article defines open and closed GOPs, identifies why closed GOPs are better, and details how to produce closed GOPs in FFmpeg with x264 and x265. The level of testing and analysis detailed here is consistent with the instruction in my book, Learn to Produce Videos with FFmpeg In 30 Minutes or Less ($34.95), and my course, FFmpeg for Adaptive …