init: 自 zomaintain/backend/rdplib 平移独立成库; module path 从上游 github.com/nakagami/grdp 改为 git.zeroonesoft.cn/golib/rdplib

2026-09-19 18:55:43 +08:00
commit 1096fbce9d
94 changed files with 36790 additions and 0 deletions
@@ -0,0 +1,38 @@
+//go:build !arm64
+
+package rdpgfx
+
+import "unsafe"
+
+// ictToBGRA converts n pixels from YCbCr (ICT) to BGRA and writes them into
+// dst (which must hold ≥ 4*n bytes).  Processing n pixels in [8]int32 arrays
+// with a scalar inner loop.
+func ictToBGRA(yRow, cbRow, crRow []int16, dst []byte, n int) {
+	const batch = 8
+	full := (n / batch) * batch
+	for base := 0; base < full; base += batch {
+		var yv, cb, cr [batch]int32
+		for k := range batch {
+			yv[k] = int32(yRow[base+k])
+			cb[k] = int32(cbRow[base+k])
+			cr[k] = int32(crRow[base+k])
+		}
+		for k := range batch {
+			ys := (yv[k] + 4096) << 16
+			bv := uint32(max(0, min((cb[k]*115992+ys)>>21, 255)))
+			gv := uint32(max(0, min((ys-cb[k]*22527-cr[k]*46819)>>21, 255)))
+			rv := uint32(max(0, min((cr[k]*91916+ys)>>21, 255)))
+			*(*uint32)(unsafe.Pointer(&dst[(base+k)*4])) = bv | gv<<8 | rv<<16 | 0xFF000000
+		}
+	}
+	for col := full; col < n; col++ {
+		yv := int32(yRow[col])
+		cb := int32(cbRow[col])
+		cr := int32(crRow[col])
+		ys := (yv + 4096) << 16
+		bv := uint32(max(0, min((cb*115992+ys)>>21, 255)))
+		gv := uint32(max(0, min((ys-cb*22527-cr*46819)>>21, 255)))
+		rv := uint32(max(0, min((cr*91916+ys)>>21, 255)))
+		*(*uint32)(unsafe.Pointer(&dst[col*4])) = bv | gv<<8 | rv<<16 | 0xFF000000
+	}
+}