+fn avg(dst: &mut [u8], dstride: usize, src: &[u8], sstride: usize, bw: usize, bh: usize) {
+ for (dline, sline) in dst.chunks_mut(dstride).zip(src.chunks(sstride)).take(bh) {
+ for (dst, src) in dline.iter_mut().zip(sline.iter()).take(bw) {
+ *dst = ((u16::from(*dst) + u16::from(*src) + 1) >> 1) as u8;
+ }
+ }
+}
+
+fn avg_2(dst: &mut [u8], dstride: usize, src: &[u8], sstride: usize, bh: usize) {
+ let _ = src[sstride + 1];
+ let _ = dst[dstride + 1];
+ dst[0] = ((u16::from(dst[0]) + u16::from(src[0]) + 1) >> 1) as u8;
+ dst[1] = ((u16::from(dst[1]) + u16::from(src[1]) + 1) >> 1) as u8;
+ dst[dstride] = ((u16::from(dst[dstride]) + u16::from(src[sstride]) + 1) >> 1) as u8;
+ dst[dstride + 1] = ((u16::from(dst[dstride + 1]) + u16::from(src[sstride + 1]) + 1) >> 1) as u8;
+ if bh == 4 {
+ let _ = src[sstride * 3 + 1];
+ let _ = dst[dstride * 3 + 1];
+ dst[dstride * 2] = ((u16::from(dst[dstride * 2]) + u16::from(src[sstride * 2]) + 1) >> 1) as u8;
+ dst[dstride * 2 + 1] = ((u16::from(dst[dstride * 2 + 1]) + u16::from(src[sstride * 2 + 1]) + 1) >> 1) as u8;
+ dst[dstride * 3] = ((u16::from(dst[dstride * 3]) + u16::from(src[sstride * 3]) + 1) >> 1) as u8;
+ dst[dstride * 3 + 1] = ((u16::from(dst[dstride * 3 + 1]) + u16::from(src[sstride * 3 + 1]) + 1) >> 1) as u8;
+ }
+}
+fn avg_4(dst: &mut [u8], dstride: usize, src: &[u8], sstride: usize, bh: usize) {
+ avg(dst, dstride, src, sstride, 4, bh);
+}
+fn avg_8(dst: &mut [u8], dstride: usize, src: &[u8], sstride: usize, bh: usize) {
+ avg(dst, dstride, src, sstride, 8, bh);
+}
+fn avg_16(dst: &mut [u8], dstride: usize, src: &[u8], sstride: usize, bh: usize) {
+ avg(dst, dstride, src, sstride, 16, bh);
+}
+