#909 improve performance 12x!

git-svn-id: https://xpra.org/svn/Xpra/trunk@13751 3bb7dfac-3a0b-4e04-842a-767bc560f471

src/xpra/codecs/argb/argb.pyx

@@ -36,25 +36,25 @@ cdef inline unsigned char clamp(int v):
 def r210_to_rgba(buf):
     assert len(buf) % 4 == 0, "invalid buffer size: %s is not a multiple of 4" % len(buf)
     # buf is a Python buffer object
-    cdef const int* cbuf = <const int *> 0
+    cdef const unsigned int* cbuf = <const unsigned int *> 0
     cdef Py_ssize_t cbuf_len = 0
     assert object_as_buffer(buf, <const void**> &cbuf, &cbuf_len)==0, "cannot convert %s to a readable buffer" % type(buf)
     return r210data_to_rgba(cbuf, cbuf_len)
 
-cdef r210data_to_rgba(const int* r210, const int r210_len):
+cdef r210data_to_rgba(const unsigned int* r210, const int r210_len):
     if r210_len <= 0:
         return None
     assert r210_len>0 and r210_len % 4 == 0, "invalid buffer size: %s is not a multiple of 4" % r210_len
     rgba = bytearray(r210_len)
     #number of pixels:
-    cdef int i = 0
-    cdef int v
+    cdef unsigned int i = 0
+    cdef unsigned int v
     while i < r210_len:
         v = r210[i//4]
-        rgba[i]  = (v&0x000003ff) >> 2
-        rgba[i+1]  = (v&0x000ffc00) >> 12
-        rgba[i+2]    = (v&0x3ff00000) >> 22
-        rgba[i+3] = clamp(((v&0xc0000000) >> 30)*85)
+        rgba[i]   = (v&0x000003ff) >> 2
+        rgba[i+1] = (v&0x000ffc00) >> 12
+        rgba[i+2] = (v&0x3ff00000) >> 22
+        rgba[i+3] = ((v&(<unsigned int>0xc0000000)) >> 30)*85
         i = i + 4
     return rgba
 
@@ -78,9 +78,9 @@ cdef r210data_to_rgb(const int* r210, const int r210_len):
     cdef int v
     while s < r210_len//4:
         v = r210[s]
-        rgb[d]  = (v&0x000003ff) >> 2
-        rgb[d+1]  = (v&0x000ffc00) >> 12
-        rgb[d+2]    = (v&0x3ff00000) >> 22
+        rgb[d]   = (v&0x000003ff) >> 2
+        rgb[d+1] = (v&0x000ffc00) >> 12
+        rgb[d+2] = (v&0x3ff00000) >> 22
         s += 1
         d += 3
     return rgb