AV1 encoding is now only 2x slower than x265. See the latest results here. I’m comparing AV1 encoders for Streaming Media Magazine. I plan to include codecs from: The Alliance for Open Media (hopefully versions 1.0/2.0) Visionular Intel Mozilla (Mozilla is out – didn’t respond to my inquiry). If there are any other codecs that should be considered, please get …
Read More »Search Results for: x265
Preliminary VMAF and PSNR Scores for New Xilinx Transcoding Appliances
Live streaming at scale is the perfect application for hardware transcoders that deliver highly-affordable encoding density. Xilinx just announced a series of transcoding appliances targeting these live streaming use cases built around the new Xilinx Real-Time (RT) Server reference architecture. I’ve been benchmarking output quality with two card-based encoders deployed in these appliances, the Alveo U30 and Alveo U50. The …
Read More »Lesson of the Week: Codecs are Not Generic
I discuss the bandwidth savings delivered by VP9 and HEVC over H264 in my course Streaming Media 101: Technical Onboarding for Streaming Media Professionals. I wanted to illustrate this with my own tests, so I used FFmpeg to encode H.264, HEVC, and VP9 output using about 25 short test files. This felt like a good time to discuss the difference …
Read More »Tuning for Metrics: What About VMAF and VP9?
If you’re comparing codecs with video quality metrics, you should consider tuning for that metric. However, x264 and x265 don’t have a VMAF tuning option. According to my analysis, it appears that tuning for PSNR is the best option and one you should strongly consider. When working with VP9, there’s an additional complication; tuning for PSNR doesn’t appear to work. …
Read More »FFmpeg to the Rescue: Decoding Files into RAM for Decode Testing
Open and Closed GOPs – All You Need to Know
This article defines open and closed GOPs, identifies why closed GOPs are better, and details how to produce closed GOPs in FFmpeg with x264 and x265. The level of testing and analysis detailed here is consistent with the instruction in my book, Learn to Produce Videos with FFmpeg In 30 Minutes or Less ($34.95), and my course, FFmpeg for Adaptive …
Read More »NETINT Transcoder Tops in Subjective HEVC Benchmark Comparison
On September 11, 2019, Streaming Media Magazine published an article entitled Hardware-Based Transcoding Solutions Roundup: Testing Performance, that compared various H.264 and HEVC encoders using objective and subjective testing. The HEVC encoders tested included Intel’s SVT (Scalable Video Technology)-HEVC, a software-based codec; NGCodec’s FPGA-based HEVC encoder (now owned by Xilinx) and x265 using the medium and veryfast presets. After the …
Read More »What Is VVC?
Versatile Video Coding (VVC) is a codec “drafted by a joint collaborative team of ITU-T and ISO/IEC experts known as the Joint Video Experts Team (JVET), which is a partnership of the ITU-T Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG),” as MPEG explains. The codec is designed to meet upcoming needs in videoconferencing, OTT streaming, mobile telephony, …
Read More »Choosing an x264 Preset
All codecs and encoding tools have a configuration option that controls the quality/encoding time tradeoff. With x264 (and x265) the preset controls that tradeoff. When choosing a preset you should consider 3 criteria: Overall quality – the overall quality produced by that preset Low frame quality – the quality of the lowest frame produced by that preset, which indicates the …
Read More »Here’s What I’m Teaching at Streaming Media West Next Month
Streaming Media West is coming up next month in the City of Los Angeles (as opposed to Huntington Beach where it’s been the last few years). Specifically, it’s at the Westin Bonaventure on November 19-20 (Tuesday/Wednesday) with pre-conference sessions on Monday the 18th. I’ll be my normal busy self with two pre-conference sessions and several presentations. Here are the dates, …
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