Tag Archives: encoding review

Here are three things to know about 2-pass x265 encoding with FFmpeg.  If you’re using -pass 1 and -pass 2 in your command string, it’s probably not working. You must use x265-params 0:pass=1 and then x265-params 0:pass=2 in the second pass. In the way we absolutely love about FFmpeg, there’s no error message if you use -pass 1/-pass 2; it …

I’m running some 1-pass vs. 2-pass comparison testing with x265. Unlike with x264 (see tests here), there’s a substantial performance penalty for running 2-pass with minimal quality benefit. I tried the no-slow-firstpass=1 setting, which only accelerated two-pass by about 14%. Here are the results from a single test file. I don’t want to process them all if there’s a magic …

Learn how thread count impacts video quality, encoding speed, and costs in FFmpeg workflows. Master configurations for optimal production and testing results.

When choosing a preset for VOD transcoding, it almost always makes sense to use the highest-quality preset, because any increase in encoding costs will typically be recouped via bandwidth savings delivered by the more efficient encoding. I covered that analysis in detail here. Note that this conclusion assumes that you deliver at a certain quality level and will boost the …

I was reminded of this recently as I prepared for a talk on AV1 readiness at the upcoming United Cloud Tech Talk. Though quality is only a single factor, I wanted to nail the quality comparisons for the talk, but didn’t have time to produce all the iterations myself. It’s been a while since I benchmarked H.264, HEVC, AV1, and …

This article provides an overview of JPEG AI, which delivers superior compression efficiency and improved performance for AI tasks like object detection. JPEG AI is an initiative by the Joint Photographic Experts Group (JPEG) aimed at developing a learning-based image coding standard that uses machine learning techniques to achieve superior compression efficiency, offering a compact representation optimized for both human …

Super-resolution techniques scale low-resolution videos to higher resolutions at high quality, and any video publisher with older, low-resolution footage should be aware of them. This article provides an overview of what super-resolution is, how it works, where to get it, and its limitations.  Introduction to Super-Resolution As stated, super-resolution describes techniques used to scale lower resolutions to higher resolutions at …

While low-latency transcoding sounds desirable, low-latency transcode settings can reduce quality and may not noticeably impact latency. Reducing latency has been a major focus for many live producers, and appropriately so, particularly for events that viewers can watch via other media, like sporting events available through satellite or cable TV. However, it’s important to understand that transcoding latency contributes minimally …

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 …