This gets rid of the variable-length scratch buffer by filtering 16
pixels at a time and writing directly to the destination.  The extra
loads this requires to load the source values are compensated by not
doing a round-trip to memory before shifting.
Signed-off-by: Mans Rullgard <mans@mansr.com>

Misaligned row artifacts showed up when a 624x352 frame was converted
to BGR24 format.  When advancing to the next row the destination linesize
was added to the last output pointer position which was not linesize aligned,
resulting in a distorted picture.
Signed-off-by: Pavel Koshevoy <pavel@apple.aragog.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Fixes overflows for large image sizes.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>

Use uintptr_t instead of plain int.  Without this change, the
comparisons will come out wrong for pointers in certain ranges.
Fixes random failures on ppc64.  Also fixes some compiler warnings.
Signed-off-by: Mans Rullgard <mans@mansr.com>

This allows using more specific implementations for chroma/luma, e.g.
we can make assumptions on filterSize being constant, thus avoiding
that test at runtime.

It just does that part in scalar form, I doubt using a vector store
over 2 array would speed it up particularly.

The function should be written to not use a scratch buffer.

For 9/10bit, it means we don't have to upscale to 16bit before
actual scaling or pixel format conversion, and thus a performance
gain.

For 9/10bit, it means we don't have to upscale to 16bit before
actual scaling or pixel format conversion, and thus a performance
gain.

This means that precision is retained when scaling between sample
formats with >8 bits per component (48bit RGB, 16bit grayscale,
9/10/16bit YUV).

This means that precision is retained when scaling between sample
formats with >8 bits per component (48bit RGB, 16bit grayscale,
9/10/16bit YUV).

Signed-off-by: Mans Rullgard <mans@mansr.com>

Remove unused variables "flags" and "dstFormat" in yuv2packed1,
merge source rows per plane for yuv2packed[12], and make every
source argument int16_t (some where invalidly set to uint16_t).
This prevents stack pollution and is part of the Great Evil Plan
to simplify swscale.

This will likely lead to a considerable performance boost,
since it removes a branch from the inner loop. Part of the
Great Evil Plan to simplify swscale.

Make yuv2yuvX16_c a function pointer for yuv2yuvX(), so that the
function pointer becomes bitdepth-independent.

Given that this compiles fine with the Apple compiler that is probably
a gcc bug, but "const vector" is nicer anyway.

Fixes compilation on PPC with Altivec enabled.

Use av_get_pix_fmt_name() instead.

Avoids a large amount of warnings about cast discarding qualifiers.