For the past few months I've been playing with Monkey's, FLAC, and Lossless Audio (la.) I know different things are important to different users, so let me just say I've been trying to strike a balance between compression and system performance during playback. I started with la at high setting. The compression is great but playback intermittently slows my other processes to a crawl. I then tried Monkey's at extra high. Playback was good but occasionally it would "skip" (it would cut out for a bit and then pick back up.) Next was FLAC at 8. It produced the same "skipping" as Monkey's. (This "skipping" makes one very paranoid especially after spending all that time and energy using EAC and lossless encoding.)

Here's some more info on my setup:
foobar 2000 v0.667
P4 1.8
256MB RAM
(This is a work PC so I can't upgrade it.)

Any advice? Will a lower encoding setting help? Will it help enough to overcome the sacrifice in compression?

Hmm... curious. I prefer FLAC, and encode with --best (same as 8), and have only had 1 (yes, one, as in "singular") instance of "skipping"... and that was a single skip, at the very beginning of the file, as I loaded a 1 hour 46 minute single-file FLAC from CD-R.

Here are the specs, for comparison:

Winamp 2.81/FLAC reference player 1.1.0 (plugin)
Pentium III-M 1.06 GHz
512 Mb RAM

... and it's a notebook.

- M.

Hmm, I've never had flac skip, and I have a compiler running in the background as often as not. It tends to be quite low CPU usage for decoding. Athlon 1.2Ghz, 512MB RAM. IIRC, flac decompression time is independant of the compression settings chosen. Methinks there is something afoul with your setup, but unfortunately I cannot guess what.

I concur, a P4 1.8 should provide LOADS of power for decoding any of these files. On my AMD Athlon 1800+, 512Mb DDR PC2700 (should be only marginally faster than your P4) I am currently listening to lossless audio without any skips WHILE encoding mp3s with LAME @ --alt-preset standard with Dibroms compile. So far I have tried FLAC, OFR, APE, WV, SHN and WMA lossless. All play fine.

I don't have any decoding trouble either, and I'm on a PIII-733 which was never packed with any good hardware in the first place.

dewey, what foobar dsps do you have enabled? what's your OS? how much CPU does foobar eat while playing?

One possibility could be excessive disk fragmentation.

Attenuator is the only active DSP (I have never messed with DSPs so it must have been there from the start.)
WinXP Pro is the OS.
My total CPU usage with FLAC runs between 1 and 22% (I also have 5 IE windows, Outlook, and a program called Reflection open.)
With la total cpu usage is between 30 and 90%
With Monkey's total cpu usage is between 1 and 20%

That could be. I'll defrag and see what happens...

What!?! Excessive defraging can cause problems?

Are you using directsound or waveout? If you're using waveout this could be a factor.

camote: he he ;-)

In case you were not joking, excessive fragmentation is not excessive defragmenting, it's insufficient defragmenting. ;-)

dewey: fragmentation is more dangerous with the fat file system. You are probably using ntfs.

Try to play with output methods (dx or ks, wo is a bad choice on xp) or increase buffer length.

Could it be that the reduction in performance is caused by the spy program running that shows your boss what you're doing instead of being hard at work?

Since you can't upgrade the system, try asking less of it. If you encode Monkey's to only "High" instead of "Extra High" you'd only lose about 2% compression and gain a lot in performance.

Try one or two tracks at -c3000 and see if that works better.

With a CPU as powerful as yours 20% should be totally out of the guestion let alone 90%!! I get OFR peaking at about 8%, but usually hanging around 2%, FLAC peaks at 4%, but usually stays bettween 0% and 2%, APE, WV, WMA and SHN all stay at 0% most of the time. So something is going funny with your comp. Check your CPU usage when the system should be idleing, if it is above 1% then something is really funky, if this is the case try reinstalling windows.

Just for reference, and to add my own experience as a FLAC user, I have never once had FLAC skip on either of my primary listening platforms. The CPU/memory stats of my systems are as follows:

1 - PC: P4m 2.0GHz, 512MB RAM

2 - Kenwood Music Keg: 74MHz ARM processor, 32MB RAM

If FLAC playback is skipping on a PC even fairly slow by modern standards, it would seem that something else would be affecting it, like perhaps fragmentation as previously mentioned. (Because no modern PC is as limited in CPU and memory as my Music Keg, and it does fine.) However, as Doctor stated, fragmentation is usually more of an issue with FAT than NTFS...and in my experience it's not much of an issue with FAT32 as well because I have never defragged my PhatNoise DMS (cartridge for the Music Keg with FAT32 formatting), and even after switching out music files on it for a year or so, FLAC playback has still never skipped.

Vorbis playback with limited overhead is another matter...

@dewey1973: As for eliminating FLAC skipping, if you're using FAT disk partitions, then disk defragmentation would be my first recommendation as well (looks like you're already trying this). If it's FAT32 or NTFS, then perhaps Norton "Disk Optimization" may make a difference (similar to defragmentation). If that doesn't work, and I know the "f" word is usually only a last resort, but formatting the disk with larger block sizes (perhaps 32K) would improve audio file playback performance. Doing this on my DMS cartridge slightly improved Vorbis playback on my Music Keg which was having skipping problems with higher bitstreams, as in >180kbps. Don't ask me how it could (even before reformatting) cleanly playback 800kbps FLAC bitstreams. Lower decoder memory requirements, perhaps?

Anyway, if you have an "extra" HDD lying around, then testing the larger blocksize approach for helping FLAC playback may be worth a try.

Edit: As for *.APE and *.LA formats, I haven't tried them, so I couldn't speak as to performance problems they may run into. I've heard, I believe, that FLAC has lower system overhead requirements than most other lossless codecs for clean (skip-free) playback.

WOW! Right over my head! ZOOM!

All I did was install foobar and use it. Are these foobar options?



LOL! Good one!

Any codec ever mentioned here on Hydrogen Audio plays fine without skipping on my PIII 450mhz abacus.

.... Ok, so I cant burn a cd at the same time.....

Bandwidth related maybe?

Testing FLAC streaming to a laptop right now (from a Samba server), using a Linksys wireless network. I get a few skips in really low signal strength areas.

Other than that, I am amazed at how well it streams.

Edit: Now that I think about it, I'm not sure if playing from a network share is the same thing as streaming.

A lot of the time, a low disk transfer rate (which seems to be causing the skipping) can be attributed to windows disabling DMA on your hard drive/CD drives.
Check that it's enabled by going to:

Control Panel -> System.
Click the Hardware tab.
Click the Device Manager button.

Find the branch in the tree named something like IDE ATA/ATAPI controllers.
under here, you should find some entried like Primary/Secondary IDE controller. Double click on them, choose Advanced Settings and make sure the boxes say "DMA if available".
Reboot.

Hope it works.

Not that anyone will agree with me, but I've found that EAC sometimes rips less-than-perfect perfect files that have missing samples. Out of 1000 or so tracks of found about 5 that have this problem.

Don't know if there is a problem with my ripping hardware but ...