G5 owners!!! PPC970 still kicks ass!!! x264 boost +33%!!!

[PhilG5]

You don't have to buy one of these new and flashy Intel Macs to get some decent H.264 (x264) encoding speeds.

The x264 build used by major is NOT optimized for G5 (PPC970) because of backwards compatibility to G4 and (possibly) G3 processors.

I've built an new x264 binary from the May 12 2006 snapshot and compiled it with GCC 4.0.1 and enbaled all compiler tuning options for G5 computers.

Test Setup:

Computer: Dual Core 2.3 GHz PowerMac G5 (late 2005) ; 2 GB DDR2-RAM ; OS X 10.4.6

VOB: Star Wars Ep. V - The Empire Strikes Back - Chapter 44 (Lightsaber figtht) ; 2:22 min.

Software: ffmpegX 0.0.9w

Test 1:

video options: 640x272 ; no crop ; 1000kbs ; PAL
x264 options: two-pass encoding ; i4x4 analysis ; B-frames
audio options: AAC 192kb ; 48 kHz; Stereo; CBR

Results:

x264 (ffmpegX standard):

pass 1: 30.30 fps
pass 2: 36.73 fps

x264 (Phil's ultimate G5-only):

pass 1: 41.73 fps (+ 36,73%)
pass 2: 47.45 fps (+ 29,19%)

average custom built x264 speedup: 33%!!!

Test 2:

video options: iPod x264 export: 320x240 ; 512 kb/s ; no crop ; i4x4 ; single pass ; constant bitrate
audio options AAC ; 96 kb/s ; 48 kHz ; CBR

Results:

264 (ffmpegX standard): 62.83 fps

x264 (Phil's ultimate G5-only): 83.59 fps (+33,04% speedup!!!)

This is an amazing improvement!!! I love my G5 again!!!

I have included my build here, you may download it, test it and tell us about your results (everything you do, you do it on your own responsibility and at yourown risk! Nevermind, just a quick reminder...) Your feedback will be greately appreciated!

How to Install

Make sure you have a G5 in front of you (other processors are definitely NOT supported!)

Download and extract the .zip file on your desktop (or whereever you like)

Look for the ffmpegX app icon (usually in your Applications folder) and Ctrl+klick on it (or use your right mouse button if available).

Select "show Package contents" from the context menu that just appeared

Open the "Contents" Folder, then open the "Resources" folder

Rename the file "x264" which is already located inside that folder into someting like "x264-old-and-slow" (or whatever name you prefer)

drag and drop the extracted x264 file into the "Resources" folder

You're DONE!!!

Switching between the "old" and "new" x264 is quite easy: just rename the files appropriately (this can be even done when ffmpegX is running, but not encoding --- try that with Windows apps )

Next steps:

1. Get some custom x264 build for G4 (my brother wants it in the first place!)

2. Get some PPC970 optimized build of xvid 1.1.0-final (even though inever use it, butyou might...)

3. Use my PPC970-build for the x264 QuickTime component (and gain 33% in iMovie export? Hell yeah!!!)

Best regards, and greetings from Munich, Germany

PhilG5

download here:

x264-g5-exclusive.zip

[Case]

Cool!

[major]

Thank you, I will check and possibly include this version with an automatic detection. I'm not sure whether this is due to compiling on a g5, or to very recent Altivec improvements which have been added to x264 after 0.0.9w was released.

[PhilG5]

ffmpegX is one of my very favourite apps, so I'm always glad to help.

configuration options were set as follows:

./configure --enable-mp4-output --enable-pthread --extra-cflags="$CFLAGS -mcpu=970 -mtune=970 -mpowerpc64 -mpowerpc-gpopt"

and that's all!

Now I'm struggling a bit with the compilation of ffmpeg, but maybe i'll get that done soon.

Already optimized binaries are available for:

libgpac
liba52
libmp3lame
libxvidcore
libfaac (with libmp4v2)

Best regards,

PhilG5

[PhilG5]

That kind of "experiment" also brings up some interersting points:

It clearly show how critical it is to adapt software to a very high degree to its hardware enivronnement in order to get the best performance out of both the program and the machine.

It also lets me doubt about the quality of Apple's very own H.264 implementation - integrated into QuickTime 7 - which really is th slowest codec I've ever tried to work with.
I haven't tested QuickTime 7.1 yet, but I don't believe it can catch up to the speed and quality of x264.

I would be very interested in having someone to run my tests on a Quad G5 Power Mac, I have a feeling that the SMP capabilities of x264 have very much improved. I am courious how well x264 - when optimizd to the G5 and 64 bit - may handle 4 processors.

best regards

PhilG5

[major]

That kind of "experiment" also brings up some interersting points:

It clearly show how critical it is to adapt software to a very high degree to its hardware enivronnement in order to get the best performance out of both the program and the machine.

To determine the performance change due only to g5 compiler flags, the same CVS sources should be compiled in both g4 and g5 environments. I'll perhaps post here a x264 from today CVS compiled on a g4 so as to make such test.

[G Rom]

That's what I was wondering !
Can we expect improvements on G4, if the lib' is "optimized" to ?

By the way, x.264 seems to be unable to handle 50fps and stay at 29.97fps.
Is this a known problem ?
Is there any issus about this problem ?
'cause, if improvement there is, I'll have to use mencoder and wont benefit of the G4 improvements...

[dr9553]

so what settings did you use for the other optimized things? or did you find them somewhere online?

[BahamutZERO]

major

The binary produced by -mcpu=g5 and -mtune=g5 (BTW, -fast might as well be used) will have architecture flags such that dyld will only load it on PPC970 hosts. You can then use lipo to make a three-architecture (generic PPC, PPC970, generic i386) version of any program or library.

[mactsk]

i have a quad, if you want to make some tests...
i noticed that no codec can use more than 160-180% on my mac
it would be a good enhancement if ffmpegx can split the video in 2 pieces, spawn 2 encodings and at last join the 2 video files.
i tried encoding 2 movies at once and the time needed is the same that it would be for one...

[badgerman]

Hi,

I have managed to compile the bin file for G4 processors, and have copied it into the ffmpegx directory as stated above, but when i try to encode in x264 the process bar just jumps from 0% to 100%, and only outputs the empty temp files?

Anyone come accross this or know how to solve it?

x264 appears to have compiled correctly as when double clicking the bin the instructions for use appear.

[lordsmurf]

Apple's very own H.264 implementation - integrated into QuickTime 7

.... is probably the worst video codec I've ever seen. I plays like trash pretty much everywhere, especially on Windows systems. Not so bad on Mac, but still pretty crappy.

I'd rather have the original RealPlayer, at least it wasn't choppy playback and a CPU hog.

[cvkB]

I hate to bring up an old thread but I am looking for a 970 optimized libx264.a & x264.h which should have been produced along with your binary. Any chance you have'em? I am at 18fps on my Dual 2 Ghz PowerPC G5. I compiled myself and increased from 11fps to 18fps. I wonder if G5 dual-cores are better in this respect. Have you done this recently with a newer snapshot?

[PhilG5]

hey i think you missed my latest shootout with newer x264 builds for both G5 and intel...and yes, it's faster again! i'm about to release a new package soon (the results are very promising, especially for intel though) so stay tuned for more to come...

[cvkB]

Can you please post the contents of your config.mak file and link to the source you used? Thanks for your G5 efforts. Do you have and good links about compiling other ppc970 encoders?