This post explores the economic factors to consider when choosing a preset for the SVT-AV1 codec. It’s adapted from a new lesson added to the course, Encoding with the AV1 Codec. While this analysis uses the SVT-AV1 codec, it’s useful for choosing a preset for any codec. I’ve always considered codec preset selection a cost and quality-driven decision. You see …
Read More »How to Compare Per-Title Encoding Systems
I just completed the first of two reports on cloud-based per-title encoding features, culminating 8 months of work. The first report details H.264 output, and the next, scheduled for release by July 18, details HEVC output. This article will detail the procedures used during this analysis which will be helpful to any company seeking to perform their own analysis to …
Read More »SVT-AV1 and Libaom Tune for PSNR by Default
As of June 22, 2022, libaom-AV1 and SVT-AV1 tune for PSNR by default, and libaom-AV1 doesn’t appear to have a mode that optimizes actual video quality. Be sure to verify and consider this when comparing the codecs to others. Most of the time with codec experimentation, a lapse in attention costs you hours, days, or weeks of re-encoding and re-testing, …
Read More »SVT-AV1 1.0 Shows Great Promise
I’ve been testing SVT-AV1 1.0 for a presentation that I’m giving on open-source AV1 encoding alternatives at Streaming Media East on May 24, 2022. The results have been impressive; two-pass VBR encoding is working well, and the codec offers a great range of presets, with several much faster than real-time. In contrast, FFmpeg’s libaom-AV1 has no presets even close to …
Read More »Finding the Optimal Top Rung Data Rate
The top rung of your encoding ladder is the most expensive to deliver, and in many regions, it’s also the most frequently viewed. Encode at too high a bit rate and you’re wasting money; encode too low, and you’re potentially reducing viewer quality of experience. This makes choosing the top rung bitrate a key task for all streaming producers. This …
Read More »Per-Title Encoding 2022
My article, Buyers’ Guide to Per-Title Encoding is up on Streaming Media. Per-title encoding is one of the simplest and least expensive ways to reduce streaming bandwidth, increase viewer QoE, or accomplish both. It’s becoming a standard feature in cloud-encoding services. The article begins with an overview of what per-title encoding is and why it’s important. Then it compares per-title …
Read More »Encoding for Transcoding vs Encoding for Distribution
A consulting client sent the following command string for a 1080p file they were encoding for upload to Vimeo, their online video platform. crf=20:vbv-maxrate=10000:vbv-bufsize=9500 What’s wrong with these parameters? First, some theory. One distinction to understand when encoding files is the difference between producing a mezzanine file to use for subsequent transcoding and encoding for distribution. When producing a mezzanine …
Read More »Estimating the Bitrate for 8K Videos When Encoding with HEVC and AV1
It’s a well-known and oft-repeated truism that codecs operate more efficiently at higher resolutions. The question is, is the truism really true? It turns out that it is, and we prove it below. To lend numbers to our truism and focus the issue, the basic question is this. 8K video has 16 times the pixels of 1080p videos. So, if …
Read More »Constrained VBR Levels of the Rich and Famous
I’ve been wondering if publishers still care about constraining their maximum bitrates (see here for more background), so I grabbed my copy of youtube-dl and performed a little study. The TL/DR version seems to be that new media sites like YouTube, Facebook, and Vimeo don’t strictly adhere to the typical 200% constrained VBR limit while traditional publishers seem to, though …
Read More »Does Anyone Care About Constrained VBR Anymore?
I’m comparing cloud-based per-title VOD encoding technologies for a report I hope to publish in the near term. In an attempt to create a level playing field I set the following specifications. 2-second GOP 200% constrained VBR 2-second VBV buffer Kind of like you were encoding with FFmpeg and using these parameters -b:v 2600k -maxrate 5200k -bufsize 5200k All cloud services …
Read More »