[Permonic]

My entire CD collection is transfered into lossless Monkey's Audio (.ape) format. The usage of my CPU (Pentium-M 1.6 MHz) is usually about 30%. I use Foobar2000, 24 fixed-point, 44.1 kHz and ASIO format as an output. The soundcard is M-Audio Transit.

Recently I discovered that when I play MP3s or even a .wav format, the CPU usage drops significantly to 4-12% range. I am curious about this phenomenon, I tried different output format (Directsound, Directsound 2.0, waveOut; Kernel Streaming doesn't work with M-Audio Transit), using 16 fixed-point, experimenting with resampler.... However in the end, the result is always the same: .ape format uses CPU about 3x more than MP3 and 6x more than .wav format.

The sample rate of .ape format is 44.1/16 bit, compression circa 40-70%.

The question is, whether this is caused by an algorithm of Monkey's Audio format itself or by a Foobar2000 Monkey's Audio plug-in? And why? What do you think about that? Do you experience the same with other soundcards?

 

[D-EJ915]

My guess is that there's a default wav "decoder" inside windows, so it really doesn't have to do anything to "decode" it whereas the APE plugin is probably not optimized in any way and just bare as far as being a quality program. In essence, the only reasonable thing I ... whatever, the plugin is just crappy. lol

 

[Iron_Dreamer]

The APE format takes more CPU useage to decode, it is a design compromise, as I understand it, so that the format will take less CPU useage to encode (hence encode faster) and get better compression other lossless compressors.

 

[ooheadsoo]

If you're tired of taking a big hit with ape, try flac. It's integer based and decodes pretty fast. My cpu shows 0%-4% - exactly the same as for mp3. Athlon 2400+ running bone stock speeds so I can keep my fan speed to a minimum.

 

[lan]

30%? Wow that's a lot. I'm at 0-1% in foobar and winamp on either WAV or APE on P4 3.2ghz. The USB based transit must be taking more CPU power?

 

[Jasper994]

I use between 9 and 12% with ape and 4-6% with flac. I'm on an XP1900+ at stock speed. Using foobar w/asio output 24bit with strong ath noise shapping dither on, at 44.1khz. With dither turned off ape uses 7-10%.

 

[kyrie]

I'm running APE right now and looks like the CPU is averaging 6% or so.

 

[Iron_Dreamer]

BTW I don't notice a difference in CPU, but then again I'm running an Athlon with 512k cache at 2.3GHz (i.e. 3400+ speeds) so it just sits a 0% no matter what kind of file I'm playing.

 

[Permonic]

Umm, thanks guys for your inputs. From what I read and I agree with lan, the problem is probably the .ape - Transit combination

. As I wrote, I use Toshiba Satellite laptop with Pentium M on 1.6 MHz, so it should handle my settings easily. BTW when I use Transit with my old ThinkPad (PII 366 MHz) with the same settings, it takes all the CPU usage.

 

[skitlets]

Now put those cpus to use. Folding@Home!!!!

 

[Permonic]

Quote:

Originally Posted by Jasper994 I use between 9 and 12% with ape and 4-6% with flac. I'm on an XP1900+ at stock speed. Using foobar w/asio output 24bit with strong ath noise shapping dither on, at 44.1khz. With dither turned off ape uses 7-10%.

Jasper, the percentage you mentioned is based on E-MU 1212m or USB Audiophile? I wonder if my high usage is based on the fact that Transit is the USB device.

 

[Merk]

a usb soundcard in general will use more of the cpu, but that has nothing to do with why ape uses more than other formats....that could be as others stated, based on the compression/decompression algorithms. This has never been a problem for me, so unfortunatly I don't have any advice for you to fix it other than use an internal soundcard to decrease the overall cpu usage, and/or use a different format such as flac.

 

[Jasper994]

Quote:

Originally Posted by Permonic Jasper, the percentage you mentioned is based on E-MU 1212m or USB Audiophile? I wonder if my high usage is based on the fact that Transit is the USB device.

1212m, USB does have a fairly large impact...

 

[aphex944]

Average around 7-8% on an Athlon64 3200+ playing APE in FB2k using a Sonica

 

[lan]

Quote:

Originally Posted by aphex944 Average around 7-8% on an Athlon64 3200+ playing APE in FB2k using a Sonica

That's interesting because you should really be getting lower CPU usage on such a fast CPU BUT you are using a Sonica which is USB based.