[x264-devel] [BUG] x264 shift exponent error when encoding a 1080p video with --no-cabac

[BugMaster]

On Wed, 18 Jul 2018 10:19:51 -0700, Sasi Inguva wrote:
> Ping. Can anybody please help look into this. Also I realize that
> the previous drive link had sharing issues, so here is the new link
> https://drive.google.com/file/d/1OG-7crvA26OkboTbLj8XDiaPwnlGISCy/view?usp=sharing

> Thanks
> On Mon, Jul 16, 2018 at 9:53 AM Sasi Inguva <isasi at google.com> wrote:

> Hi, 

> I found a bug in x264 code, when compiled with -fsantize=shift-exponent.
> When I tried to encode the attached test file with --no-cabac, the
> encoding fails with this error
> common/vlc.c:84:27: runtime error: shift exponent 32 is too large for 32-bit type 'int'

> Here is the full command line and logs:
> make clean && ./configure  --enable-pic --enable-static --extra-cflags="-fsanitize=shift-exponent" --extra-ldflags="-fsanitize=shift-exponent" && make -j12 && \
> ./x264 --no-cabac --input-res 1920x1080  -o ~/temp.mkv  ~/test_short.yuv

> yuv [info]: 1920x1080p 0:0 @ 25/1 fps (cfr)
> common/vlc.c:84:27: runtime error: shift exponent 32 is too large for 32-bit type 'int'
> x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
> x264 [info]: profile High, level 4.0
> x264 [info]: frame I:1     Avg QP:13.37  size: 53514               
> x264 [info]: frame P:27    Avg QP:20.41  size: 26810
> x264 [info]: frame B:2     Avg QP:28.24  size: 22252
> x264 [info]: consecutive B-frames: 90.0%  0.0% 10.0%  0.0%
> x264 [info]: mb I  I16..4: 83.7%  9.5%  6.9%
> x264 [info]: mb P  I16..4:  2.1%  1.0%  0.1%  P16..4:  6.7%  3.3%  1.2%  0.0%  0.0%    skip:85.6%
> x264 [info]: mb B  I16..4:  0.2%  0.1%  0.2%  B16..8:  6.8%  2.6% 
> 0.7%  direct: 1.6%  skip:87.8%  L0:41.9% L1:43.1% BI:15.0%
> x264 [info]: 8x8 transform intra:19.7% inter:62.8%
> x264 [info]: coded y,uvDC,uvAC intra: 9.3% 16.8% 14.3% inter: 3.8% 7.5% 6.5%
> x264 [info]: i16 v,h,dc,p: 93%  6%  2%  0%
> x264 [info]: i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 20% 11% 61%  3%  1%  1% 2%  2%  1%
> x264 [info]: i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 35% 28% 16%  6%  2%  2% 4%  3%  3%
> x264 [info]: i8c dc,h,v,p: 79% 10%  9%  1%
> x264 [info]: Weighted P-Frames: Y:0.0% UV:0.0%
> x264 [info]: ref P L0: 65.6%  9.1% 16.7%  8.6%
> x264 [info]: ref B L0: 72.0% 28.0%
> x264 [info]: kb/s:5479.23

> encoded 30 frames, 55.51 fps, 5484.05 kb/s

> ​​Please let me know if you need more information. Attaching the
> file as a drive link, because sending as attachment did not work.

> Thanks,
> Sasi

Hi.

Can you try with attached patch that should fix it.
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