[Ffmpeg-devel] Illegal instruction error for ffmpeg and x264 on Intel iMac

Guillaume POIRIER poirierg
Fri Mar 31 21:16:46 CEST 2006

On 3/31/06, Laine Lee <llee at lonestar.utsa.edu> wrote:
> I'm trying to use ffmpeg and x264 in combination to convert mpeg2 to h.264
> mp4 on an Intel iMac. The iMac has Mac OS X 10.4.5 and the latest version of
> the Xcode developer tools installed. Both ffmpeg and x264 have been
> successfully compiled on both the Intel and a PPC with the following
> configuration.
> The configuration of ffmpeg compiled from today's CVS is
> "--enable-faac --enable-faad --disable-vhook --disable-ffplay
> --disable-ffserver --enable-a52 --enable-x264 --enable-pthreads --enable-gpl
> --enable-memalign-hack --disable-mmx". The "--enable-memalign-hack" and
> "--disable-mmx" were omitted when building on a PPC.
> The configuration of x264, the source of which is the latest source download
> from videolan.org, is "--enable-pthread --enable-mp4-output".
> The command issued is "ffmpeg -i /video.mpg -f rawvideo -s 320x240 - | x264
> -o /output.mp4 - 320x240"
> The above command can be executed successfully on the Intel and on a PPC
> when ffmpeg and x264 are built with the above configuration on a PPC. It can
> be executed successfully on the Intel when ffmpeg is built with the above
> configuration on either the Intel or the PPC and x264 is built with the
> above configuration on a PPC. If x264 is built with the above configuration
> on the Intel, the command fails on the Intel with the following output in
> the Terminal window.
> ...
>  libavutil version: 49.0.0
>   libavcodec version: 51.8.0
>   libavformat version: 50.4.0
>   built on Mar 31 2006 12:29:38, gcc: 4.0.1 (Apple Computer, Inc. build
> 5250)
> x264 [info]: using cpu capabilities MMX MMXEXT SSE SSE2
> mp4 [info]: initial delay 0 (scale 25)
> Input #0, mpeg, from '/video.mpg':
>   Duration: 00:00:26.4, start: 5810.226022, bitrate: 4341 kb/s
>   Stream #0.0[0x1e0], 29.97 fps(r): Video: mpeg2video, yuv420p, 720x480,
> 7000 kb/s
>   Stream #0.1[0x80]: Audio: ac3, 48000 Hz, 5:1, 448 kb/s
> Output #0, rawvideo, to 'pipe:':
>   Stream #0.0, 29.97 fps(c): Video: rawvideo, yuv420p, 320x240, q=2-31, 200
> kb/s
> Stream mapping:
>   Stream #0.0 -> #0.0
> Press [q] to stop encoding
> Illegal instruction
> Why can the command be completed successfully on the Intel using the PPC
> built version of x264 but not the Intel built version? Thanks.

You need to provide more information in order to know what is the
problematic instruction. Please follow the bug reports guidelines:

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telepathic power :).

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