FFmpeg

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The Quality Cost of Low-Latency Transcoding

Figure shows the different components to live streaming latency.

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 …

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My FFmpeg-Related New Year’s Resolution: Document Before I Test

My typical workflow for testing-related articles and reports is to create the command string, run the tests, analyze the results, and then write or create the presentation. Since encoding is often so time-consuming, and I’m always in a hurry, I tend to quickly create the command strings with minimal thought, then run the tests, analyze the results, and start to …

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Which is the Best AWS CPU for FFmpeg?

Figure 2. Cost per hour to produce a single 1080p stream using the x264 codec and FFmpeg. Graviton is clearly the most cost effective.

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 …

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Running FFmpeg on Windows Subsystem for Linux

Choosing the Linux distro.

This post details how to install, update and add FFmpeg to Windows Subsystem for Linux so you can run Linux in Windows with minimal muss or fuss. Here’s why you might want to install WSL in the first place. I recently taught a session at Streaming Media East on using variables with FFmpeg (download handout here – note that free …

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Maximizing Quality and Throughput in FFmpeg Scaling

Maximizing Quality and Throughput in FFmpeg Scaling

The thing about FFmpeg is that there are almost always multiple ways to accomplish the same basic function. In this post, we look at four approaches to scaling. We found that if you’re scaling using the default -s function (-s 1280×720), you’re leaving a bit of quality on the table as compared to other methods. How much depends upon the …

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How to Build an Encoding Ladder: What You Need to Know

Learning how to build an encoding ladder is one of the most fundamental tasks for a streaming media professional. It’s astounding how much you need to know to get it right. By way of background, the original encoding ladder used by most professionals was from Apple Tech Note TN2224, long since replaced by Apple’s HLS Authoring Specifications. This H.264-only ladder …

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Choosing a Preset for SVT-AV1 and libaom-AV1

This article shows the quality/encoding time tradeoffs for producers choosing a preset for SVT-AV1 and libaom-AV1. Note to readers – 12/13 – AOM has released version 1.4, which fixed the SVT-AV1 preset issues reported in the first version of this article.  Presets are the most important configuration option for controlling quality and throughput for most codecs. For this reason, when …

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SLC Updates AV1 Encoding Course

The course Encoding with the AV1 Codec has been updated with new instructions for SVT-AV1 1.0 and FFmpeg/libaom-AV1.  AV1 is a powerful codec but to optimize quality and performance, you have to choose the optimal preset and thread count and then navigate through obscure commands like auto-alt-ref, row-mt, tile columns/tile rows, and lag-in-frames. The course, Encoding with the AV1 Codec, provides …

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Learn to Encode with FFmpeg 5.0

My tutorial How to Encode with FFmpeg 5.0 is up on Streaming Media.com. By way of background, on January 17, 2022, FFmpeg released FFmpeg 5.0, called Lorentz. To celebrate and to help introduce new users to the power and ease of FFmpeg, I created this entry-level tutorial for single and two-pass encoding with FFmpeg. You’ll learn basics like: Choosing the …

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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 …

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