A couple of additional data points on AV1 encoding as follow-ups to my Streaming Media article here. First, a colleague asked about 4K encoding times on Twitter. Second, a reader recommended using the row-mt switch for VP9. So, I encoded a ten-second 4K test file on the same single-CPU ZBook as the Streaming Media article. I used the same basic …

When I first tested AV1 encoding back in August 2018 encoding times were glacial and seriously detracted from the potential usability of the codec. Table 1 from that story tells the tale. Unless otherwise indicated, all encoding times are on my HP ZBook notebook powered by a single 2.8 GHz Intel Xeon E3-1505M v5 CPU. In addition, LibVPx is the …

I frequently use the VMAF quality metric to analyze encoding parameters and compare codecs. In my experience, VMAF scores tend to match my own subjective quality observations and the fact that Netflix uses it gives the metric great credibility. Originally, there was only one VMAF version, but Netflix has added both a 4K model and a phone model, increasing the …

I’m writing a blog post on a free Netflix utility called VMAF-Master that you can download here (Windows executable here). Basically, it’s an open-source command line utility for computing VMAF, PSNR, SSIM, and MS SSIM on Linux and Mac computers with some enterprising contributors compiling a Windows version. One very well written help file relates to the models available under …

According to the last published statistics, in June 2017, Whatsapp users sent over 1 billion video messages a day. This obviously represents only a fraction of the market and daily traffic has certainly has grown since then. At the same time, 4K cameras have become standard and mobile screen resolutions have increased in size and quality, driving demand for higher …

I recently finished a streaming consulting project with AMC Networks and was pleased to receive the following LinkedIn recommendation from their VP of Video Products. It was great working with Greg and his team with the gorgeous content from AMC. Beyond this work with AMC, I’ve helped media companies and video publishers fine-tune their encoding parameters, modernize their encoding ladders, …

I just finished a project that involved encoding lots of downloaded YUV test files, which is something I never tried before. The problem is that there’s no resolution or frame rate information in the file header, so you have to detail all this in the command string. My first crack at the problem evolved into this command string, obviously for a …

In this January 2019 article in Streaming Media Magazine, I reported that two patent holders in the MPEG-LA patent portfolio group had sued Huawei and ZTE in Germany for patent infringement and had won. As stated therein, “the judgment was particularly onerous; not only did the court order the two companies to stop selling the offending mobile phones in Germany, they …

Moscow State University’s Video Quality Measurement Tool (VQMT) has been my go-to file analysis tool dating back to 2014 (see my initial review, here, and an update, here). As you can see in this video, version 11 of the tool adds several new features, including support for the VMAF 4K model, data rate graphs, and a results table. I’ve also …