goldfish-camera: using float to do dot product
Prepare for SSE version.
Test: take video and picture looks almost the same as
integer version, and faster because of no division.
Change-Id: I1d7813c04249b983d5bf5b169c50da5339b4e7be
diff --git a/camera/fake-pipeline2/Sensor.cpp b/camera/fake-pipeline2/Sensor.cpp
index f3ee64f..fb85035 100644
--- a/camera/fake-pipeline2/Sensor.cpp
+++ b/camera/fake-pipeline2/Sensor.cpp
@@ -507,12 +507,18 @@
// Fixed-point coefficients for RGB-YUV transform
// Based on JFIF RGB->YUV transform.
// Cb/Cr offset scaled by 64x twice since they're applied post-multiply
- const int rgbToY[] = {19, 37, 7};
- const int rgbToCb[] = {-10,-21, 32, 524288};
- const int rgbToCr[] = {32,-26, -5, 524288};
+ float rgbToY[] = {19.0, 37.0, 7.0, 0.0};
+ float rgbToCb[] = {-10.0,-21.0, 32.0, 524288.0};
+ float rgbToCr[] = {32.0,-26.0, -5.0, 524288.0};
// Scale back to 8bpp non-fixed-point
const int scaleOut = 64;
const int scaleOutSq = scaleOut * scaleOut; // after multiplies
+ const double invscaleOutSq = 1.0/scaleOutSq;
+ for (int i=0; i < 4; ++i) {
+ rgbToY[i] *= invscaleOutSq;
+ rgbToCb[i] *= invscaleOutSq;
+ rgbToCr[i] *= invscaleOutSq;
+ }
unsigned int DivH= (float)mResolution[1]/height * (0x1 << 10);
unsigned int DivW = (float)mResolution[0]/width * (0x1 << 10);
@@ -538,18 +544,10 @@
gCount = gCount < saturationPoint ? gCount : saturationPoint;
bCount = pixel[Scene::B] * scale64x;
bCount = bCount < saturationPoint ? bCount : saturationPoint;
- *pxY++ = (rgbToY[0] * rCount +
- rgbToY[1] * gCount +
- rgbToY[2] * bCount) / scaleOutSq;
+ *pxY++ = (rgbToY[0] * rCount + rgbToY[1] * gCount + rgbToY[2] * bCount);
if (outY % 2 == 0 && outX % 2 == 0) {
- *pxVU++ = (rgbToCr[0] * rCount +
- rgbToCr[1] * gCount +
- rgbToCr[2] * bCount +
- rgbToCr[3]) / scaleOutSq;
- *pxVU++ = (rgbToCb[0] * rCount +
- rgbToCb[1] * gCount +
- rgbToCb[2] * bCount +
- rgbToCb[3]) / scaleOutSq;
+ *pxVU++ = (rgbToCr[0] * rCount + rgbToCr[1] * gCount + rgbToCr[2] * bCount + rgbToCr[3]);
+ *pxVU++ = (rgbToCb[0] * rCount + rgbToCb[1] * gCount + rgbToCb[2] * bCount + rgbToCb[3]);
}
}
}
