ffmpeg … -c:a flac -exact_rice_parameters 1 -multi_dim_quant 1 …
I was encoding wav to flac.
- With default options, the result was almost instant
- At > 500x speed
- Used
-compression_level 12, finished in ~ 7 seconds- speed = 48.9x
- Then I used
multi_dim_quant- After ~ 10 minutes, I checked the speed to be ~ 0.02x. So thought it would take an hour or so. 1.30 seconds worth of audio was encoded
- It’s been over 2 hours now.
- Shows 1.46 seconds of audio encoded with current speed = 0.00017x
Considering running it in a VM, so I can “pause” it whenever I need to restart my computer.
Update:
size= 123KiB time=00:00:02.82 bitrate= 356.3kbits/s speed=4.68e-05x
It stopped trying to use layman notation.
I’ll need to restart soon-ish, but I’ll see how far this goes and if the 2.82 seconds of audio is even listenable.
Well, my RAM usage doesn’t seem to have increased though (at least from this process).
And I haven’t setup a swap.
Oh, it has a CUDA library!?
Then this FFmpeg FLAC library is really basic, considering it has no parallelism. I was assuming that the algorithm itself is not parallelisable.
It’s OpenCL, so it should even run on integrated graphics.
Yeah, it’s great! Extremely fast and marginally smaller than ffmpeg, last I checked, though I have not messed with those newer ffmpeg options. And cuetools has some other nice utilities anyway.