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Comment by DarkShikari | Hacker News Reader

Hardware encoders are not feasible for ordinary consumers at all; if you want an encoder that produces reasonable compression, you have to go up to the $10k-$50k range (and even there, most of the ones on the market are really not very good!). Low-end hardware encoders are both often slow (usually outperformed by x264 on a cheap quad-core CPU) and extremely bad at compression.

Plus, a CPU can be used for things other than encoding video, while a hardware device is of course useless for anything else, so it's easier to justify spending money on a fast CPU than on a task-specific piece of hardware.

Also, it isn't really an edge case; it will occur in any application which has a working set that is unavoidably larger than the L1 cache. Video encoders are just one of many cases where this occurs.

(Note: added that last point to the blog post after I posted this.)

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Thanks for the follow-up. After re-reading the post, I see that this is not /just/ an x264 problem.

Thank you also for informing me that hardware encoders aren't very good. I had actually considered purchasing one of the ~$100 ones, but now I'll steer clear.

I must be doing something wrong, though, because I can't seem to get much better than 2x real-time on my Q6600 w/ 4GB memory when using x264.

The meaning of 2x real-time, of course, depends entirely on the resolution.

x264 now has encoding presets you can use to trade off speed for compression: they go from "ultrafast" to "placebo" (full list in the help). Grab the latest from x264.nl; we've also had a lot of speed improvements lately ;).

Do note that at high speeds, it's easy to get bottlenecked: the most common case is the decoding of the input, which is often only single-threaded. If your input is uncompressed, then you can get bottlenecked by reading it off the disk. And if you're running filters on the input (e.g. resizing it), that can also serve as a bottleneck.

I've used Elgato's Turbo.264 dongle, and as far as I'm concerned it did a good job. It cost roughly $150, and outperformed any software encoding I could manage by a large margin. Of course, if I had the money to build a dedicated computer and figure out the settings to ffmpeg (or some other software encoder) I might get even better results, but for my needs (MacBook, don't want to learn the intricacies of encoding) it's perfect.

I think that quite a few "ordinary consumers" would share my opinion. If they don't mind spending hours or days compiling and tweaking a delicate chain of open source software, they're not "ordinary" - they're power users.

I looked into the same dongle (also for a Macbook) and the general impression I got was that it was maybe better than Apple's Quicktime on slower machines but that you could easily beat it with open source encoders. The only reason it is difficult to make the comparison is that the software encoders generally didn't take the same shortcuts as the hardware encoder because they didn't feel the quality tradeoffs were worth it.

This was a while ago, but I have no reason to think the software encoders haven't improved faster than the hardware.

edit: rereading your post I see your main problem with the software solution is "spending hours or days compiling and tweaking a delicate chain of open source software". I can't help but note that if that is the case then you're doing it wrong™.

I can't help but note that if that is the case then you're doing it wrong™.

Most likely, but since ffmpeg has the least helpful documentation I've seen (for a newbie at least), I'm not surprised.

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