[MPlayer-dev-eng] MPlayer/MEncoder crash on using -vf scale and expand together. Fix attached.

[Ivan Kalvachev]

On 10/28/11, Alex C <alexc.xander at yahoo.in> wrote:
> Problem: SIGSEGV on mplayer -vf scale=720:480,expand=720:480 test.mkv
>
> Sample test file:
> https://ffmpeg.org/trac/ffmpeg/attachment/ticket/594/rotate_x.mp4
>
> Backtrace on: http://pastebin.com/uHPRtswz
>
> Similar to ffmpeg bug:
> https://ffmpeg.org/trac/ffmpeg/ticket/594?cversion=1&cnum_hist=4
>
> Patched in ffmpeg by michaelni:
> http://git.videolan.org/gitweb.cgi?p=ffmpeg.git;a=commitdiff;h=3e4375833d964ebb5d38816126ff0101ae696cf9;hp=d7dcd96a2377835a20c3d23b3bd476ddcf1baebb
>
> I have applied a similar patch for mplayer. Patch is attached. The crash is
> averted as a result.

Your patch is reverted (aka the newer file is at ---).
I'm also keeping the MP_IMGFLAG_ACCEPT_STRIDE, it is needed for the xv
direct rendering. I'm also applying this to the second vf_get_image()
at line 379 in start_slice() function.

No need to resend the patch, I'll commit in a minutes.
I'll use this commit message.
--------------
Fix segfault in scale due to unaligned stride.

The MP_IMGFLAG_PREFER_ALIDNED_STRIDE is honored only
in MP_IMGTYPE_EXPORT, but vf_scale uses it only with MP_IMGTYPE_TEMP.
As result stride is not aligned and this causes misalignment for SSE code.

Use MP_IMGFLAG_ACCEPT_ALIDNED_STRIDE instead, that aligns it in all cases.

Solution and initial patch by alexc.xander.yahoo.in.