avformat/matroskadec: fix off by 1 error in matroska_read_seek()

Fixes out of array read

Fixes: vp9-opus-crash.webm

Found-by: Dale Curtis <dalecurtis@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
x86: huffyuvdsp: add SSE2 median prediction

From 5010c to 4566 on lagarith YUY2.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/huffyuvdsp: Change w to intptr in add_hfyu_median_pred() and add_hfyu_left_pred()

This avoids potential issues with the high 32bits being random in x86-64 asm

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
x86: huffyuvdsp: add_hfyu_left_pred_bgr32

          C   MMX   SSE2
Cycles: 3092  1053  578

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
tests: Add MPEG4 nsse test

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
x86: dsputilenc: move all the function prototypes together

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
x86: dsputilenc: convert ff_sse{8, 16}_mmx() to yasm

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Fix VDPAU decoders, regression since f2f99f07.