Tag Archives: encoding review

This article discusses five common errors that can be obscured by automated video quality assessment scripts and how to avoid them.  Most video producers use some measure of automated testing in their codec or encoder comparisons or during normal production. While automated testing is essential, it’s easy to make the five following errors if you don’t spot-check your results. The …

The mandate for streaming producers hasn’t changed since we delivered RealVideo streams targeted at 28.8 modems; that is, we must produce the absolute best quality video at the lowest possible bandwidth. With cost control top of mind for many streaming producers, let’s explore five codec-related options to cut bandwidth costs while maintaining quality. For each, I’ll consider the factors summarized …

Let’s start this article with a quiz regarding how the quality and encoding speed of two-pass VBR (variable bitrate encoding) compares to single-pass VBR (that’s right, VBR in both cases). Choose the best answer. Two-pass takes twice as long as single-pass but delivers significantly better overall quality. Two-pass takes slightly longer than single-pass but delivers significantly better quality. Two-pass takes …

This freely downloadable report measures the qualitative impact of GOP sizes on animated, general entertainment, sports, and office footage for H.264 and HEVC. One of the most fundamental encoding decisions is GOP size or the frequency of I-frames in our encoded files. I-frames, also called keyframes, start each “group of pictures” comprised of I-, B-, and P-frames. Most of the …

This case study compares CAPEX, power consumption, and co-location costs for GPU, CPU, and ASIC-based transcoding.  This case study was derived from Ilya Mikhaelis‘ recent talk at NETINT’s symposium on Building Your Live Streaming Cloud. Images have been consolidated and modified slightly. You can view Ilya’s talk and download his slides here: bit.ly/vovs.   Ilya Mikhaelis is the streaming backend tech …

There are four bitrate control techniques worth considering for live encoding/transcoding using the SVT-AV1 codec. These are: Capped CRF VBR Capped VBR Constrained VBR Here’s what I found: Overall: Capped CRF shows promise with significant bitrate savings, good quality retention, and the best overall performance by ~10 – 25% (meaning more streams from the same hardware). VBR was generally the …

Recently I was asked to visually illustrate the data rate difference between two HEVC files, one encoded with CBR at 6 Mbps, the other using capped CRF with the same cap. Of course, everyone’s go-to bitrate visualization viewer has always been Bitrate Viewer, which does a great job displaying the bitrate of a single H.264-encoded file. Unfortunately, it can’t input …

One of my sweetest memories of bringing up our two daughters was weekly trips to the grocery store. Each got a $5.00 bribe for accompanying their father, which they happily invested in various tchotchkes that seldom lasted the week. When we exited the car, “parking lot rules” always applied, which meant that each daughter held one of Daddy’s hands for …

If you encode with FFmpeg on AWS, you probably know that you have three CPU options: AMD, Graviton, and Intel. Which is the best AWS CPU for FFmpeg? This article reveals all. For those in a hurry, it’s Graviton for x264 and AMD for x265, often by a significant margin. But the devil is always in the details, and if …

To choose the optimal x264 preset, you have to balance encoding and distribution costs. This article shows you how.  Over the last few years, I’ve used the first chart below to represent the tradeoffs associated with different presets and help readers (or listeners) choose a preset. To create the chart, you encode your test files to standard parameters using all …