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Next-Gen Video Encoding: x265 Tackles HEVC/H.265
An anonymous reader writes "Late last night, MulticoreWare released an early alpha build of the x265 library. x265 is intended to be the open source counterpart to the recently released HEVC/H.265 standard which was approved back in January, much in the same way that x264 is used for H.264 today. Tom's Hardware put x265 through a series of CPU benchmarks and then compared x265 to x264. While x265 is more taxing in terms of CPU utilization, it affords higher quality at any given bit rate, or the same quality at a lower bit rate than x264."
(Reader Dputiger writes points out a comparison at ExtremeTech, too.)
25-35% less file size for the same quality is an incredible advance. Obviously the task of improving compression algorithms is going to ratchet up enormously as the file sizes get smaller with higher entropy. I'm in fact amazed that an advance this big is even possible, apparently, x264 is nowhere near the theoretical limits for (lossy) video compression.
The HM reference encoder takes roughly 40 seconds to encode one frame of 1080P video on a dual Xeon (16 core) server. x265 can encode 1080P at roughly 11 frames per second today. The project is still early in development, and there are many features (lookahead, B-frames, rate control, etc) and efficiency/performance optimizations left to be done, but we are making good progress. I would encourage you to try it before reaching any conclusions.
This project is not a surprise to any of the x264 developers - we have been in discussions with them for many weeks, and we have an agreement which allows us to utilize x264 code in x265. The x264 developers haven't had a chance to make contributions yet, as we just opened the project up to participation by the open source development community. We welcome their participation, and will do everything we can to enable and encourage it.
we have an agreement which allows us to utilize x264 code in x265
You don't need an 'agreement' to use x264 code because x264 is licensed under the terms of the GNU GPL v2.0. What, exactly, is this agreement supposed to permit?
Lurking at the bottom of the gravity well, getting old
If it's anything like H.264/x264 then I expect to have the hardware to decode H.265/x265 in my laptop about 2 years after movies and tv shows are being distributed in this format, but 2 years before there are any linux drivers for the hardware decoders.