Hi Doug, Sorry didn't get back to you earlier - Been moving house!
On Thu, Mar 6, 2008 at 11:16 AM, Douglas Kosovic <dougl...@itee.uq.edu.au> wrote: > Hi Piers, > > Just wondering if you get the grey bar at the top of a 1/4 NTSC (i.e > shift-M) or NTSC (shift-L) video window? See attached PNG file (ignore > the blue mute, I don't have a camera to connect to my DVB PCI card at > home). It looks like the image is pushed down by the same number of > pixels as the bar. I seem to have that issue regardless of which version > of FFMpeg/SWScaler is used. > Yes I see the grey band at the top on my OSX [Intel] MacBook - I"m not sure what the cause is right now - it looks some miscalculation of the padding relating to PAL/NTSC. I was also trying to look into a performance issue Tom was seeing with his gpl vic on OSX: http://www.mcs.anl.gov/~turam/AG/vic.intel-osx.tom.gpl the only odd thing I can see is when I run otool -L on the binary and on his one I get: /System/Library/Frameworks/QuickTime.framework/Versions/A/QuickTime (compatibility version 1.0.0, current version 200.0.0) Whereas with mine (which runs fine) I get: /System/Library/Frameworks/QuickTime.framework/Versions/A/QuickTime (compatibility version 1.0.0, current version 70.0.0) I'm not clear what the "current version" refers to exactly....I've run a trace on it and not uncovered anything strange as yet... > I've reverted to ffmpeg svn -r 7110 and libswscale svn -r 21687 and VIC > doesn't crash in the MMX2 libswscaler code with i386 Fedora. I think I > might just disable the MMX2 code with a patch for the x86-64 build by > using a conditional in the RPM spec file for the time being. > Ah ok that sounds good - it tricky to know which rev of ffmpeg to go for as they don't seem to label them 'stable' as far as I've seen. I guess picking a release used by Linux distro isn't a bad starting point. Thanks, Piers. > > Thanks, > Doug > > > > Douglas Kosovic wrote: > > Hi Piers, > > > >>> For Fedora 8 (i386 & x86-64), issue the following: > >>> yum update AccessGrid > >>> > >>> which will install the mpeg4/h264 services and a new version of vic. > >>> > >>> Known issues: thumbnails for H.264 and MPEG-4 appear black, but video > >>> windows are fine. This is because the software scaler that comes with > >>> FFMpeg has been disabled to avoid a crash in some MMX2 assembly code > >>> and > >>> the old vic scalar doesn't support the required colorspace. I might > >>> have > >>> a newer version of vic released later in the week if I'm able to > >>> resolve > >>> the issue. > >>> > >> Thanks for sorting the RPMs out - > > > > Actually I haven't sorted the RPMs out yet, I wanted to use > > 'alternatives' mechanism to release several different VIC RPMs built > > with different build options, unfortunately there are issues when > > performing a rpm update from an older VIC rpm which doesn't use > > alternatives. The workaround is convoluted and involves RPM triggers. > > > > It might be for the better as more choices of VIC would only confuse > > things for users. > > > > > When do you see the crash occurring? > > > > With H.261 CIF video window as soon as I increase the window size, > > color-swscale crashes. > > > > If I do what one version of VLC I found does, which is disable the > > SWS_CPU_CAPS_MMX2 flag, see attached patch, it works for me. > > > > > It runs ok on my machines - I guess the snag may be compile-time > > > assembly optimisations...though at least some of it is runtime. You > > > could try using a later version of ffmpeg - we just need to make sure > > > its stable on all three platforms. > > > > I think it may have something to do with PIC addressing which > > subsequently results in the wrong register(s) being used with MMX2. > > > > I think I might try the Ubuntu ffmpeg patches ( > > ffmpeg_0.cvs20070307-5ubuntu6.diff.gz ) available here: > > http://archive.ubuntu.com/ubuntu/pool/main/f/ffmpeg/ > > which has -fPIC and assembly related patches. > > > > I've tried a few version of ffmpeg and libswscale (I made sure ffmpeg > > and libswcale had the same datestamps). > > > > When I mentioned I thought the Fedora 8 livna repository's ffmpeg was > > built with swscale in an email a few weeks ago, I was wrong, it isn't > > built with swscale. > > > > > > Cheers, > > Doug > > > > > > ------------------------------------------------------------------------ > > > > Index: render/color-swscale.cpp > > =================================================================== > > --- render/color-swscale.cpp (revision 4125) > > +++ render/color-swscale.cpp (working copy) > > @@ -70,12 +70,15 @@ > > > > #ifdef RUNTIME_CPUDETECT > > flags |= (available_cpu_flags & FF_CPU_MMX ? SWS_CPU_CAPS_MMX > : 0); > > +#if 0 > > flags |= (available_cpu_flags & FF_CPU_MMXEXT ? > SWS_CPU_CAPS_MMX2 : 0); > > +#endif > > flags |= (available_cpu_flags & FF_CPU_3DNOW ? > SWS_CPU_CAPS_3DNOW : 0); > > flags |= (available_cpu_flags & FF_CPU_ALTIVEC ? > SWS_CPU_CAPS_ALTIVEC : 0); > > #elif defined(HAVE_MMX) > > flags |= SWS_CPU_CAPS_MMX; > > - #if defined(HAVE_MMX2) > > + //#if defined(HAVE_MMX2) > > + #if 0 > > flags |= SWS_CPU_CAPS_MMX2; > > #endif > > #elif defined(HAVE_3DNOW) > >
