const int ITUR_BT_601_CVR = 1673527;
const int ITUR_BT_601_SHIFT = 20;
+// Coefficients for RGB to YUV420p conversion
+const int ITUR_BT_601_CRY = 269484;
+const int ITUR_BT_601_CGY = 528482;
+const int ITUR_BT_601_CBY = 102760;
+const int ITUR_BT_601_CRU = -155188;
+const int ITUR_BT_601_CGU = -305135;
+const int ITUR_BT_601_CBU = 460324;
+const int ITUR_BT_601_CGV = -385875;
+const int ITUR_BT_601_CBV = -74448;
+
template<int bIdx, int uIdx>
struct YUV420sp2RGB888Invoker
{
///////////////////////////////////// RGB -> YUV420p /////////////////////////////////////
-template<int bIdx, int uIdx>
-static void cvtRGBtoYUV420p(const Mat& src, Mat& dst)
+template<int bIdx>
+struct RGB888toYUV420pInvoker: public ParallelLoopBody
{
- //const float coeffs[] = { 0.257f, 0.504f, 0.098f,
- // -0.148f, -0.291f, 0.439f,
- // -0.368f, -0.071f };
- const int coeffs[] = { 269484, 528482, 102760,
- -155188, -305135, 460324,
- -385875, -74448 };
-
- const int w = src.cols;
- const int h = src.rows;
+ RGB888toYUV420pInvoker( const Mat& src, Mat* dst, const int uIdx )
+ : src_(src),
+ dst_(dst),
+ uIdx_(uIdx) { }
- const int cn = src.channels();
- for( int i = 0; i < h / 2; i++ )
+ void operator()(const Range& rowRange) const
{
- const uchar* row0 = src.ptr<uchar>(2*i);
- const uchar* row1 = src.ptr<uchar>(2*i + 1);
-
- uchar* y = dst.ptr<uchar>(2*i);
- uchar* u = dst.ptr<uchar>(h + i/2) + (i % 2) * (w/2);
- uchar* v = dst.ptr<uchar>(h + (i + h/2)/2) + ((i + h/2) % 2) * (w/2);
- if( uIdx == 2 ) std::swap(u, v);
+ const int w = src_.cols;
+ const int h = src_.rows;
- for( int j = 0, k = 0; j < w * cn; j += 2*cn, k++ )
+ const int cn = src_.channels();
+ for( int i = rowRange.start; i < rowRange.end; i++ )
{
- int r00 = row0[2-bIdx + j]; int g00 = row0[1 + j]; int b00 = row0[bIdx + j];
- int r01 = row0[2-bIdx + cn + j]; int g01 = row0[1 + cn + j]; int b01 = row0[bIdx + cn + j];
- int r10 = row1[2-bIdx + j]; int g10 = row1[1 + j]; int b10 = row1[bIdx + j];
- int r11 = row1[2-bIdx + cn + j]; int g11 = row1[1 + cn + j]; int b11 = row1[bIdx + cn + j];
-
- int y00 = coeffs[0]*r00 + coeffs[1]*g00 + coeffs[2]*b00 + (1 << (ITUR_BT_601_SHIFT - 1)) + (16 << ITUR_BT_601_SHIFT);
- int y01 = coeffs[0]*r01 + coeffs[1]*g01 + coeffs[2]*b01 + (1 << (ITUR_BT_601_SHIFT - 1)) + (16 << ITUR_BT_601_SHIFT);
- int y10 = coeffs[0]*r10 + coeffs[1]*g10 + coeffs[2]*b10 + (1 << (ITUR_BT_601_SHIFT - 1)) + (16 << ITUR_BT_601_SHIFT);
- int y11 = coeffs[0]*r11 + coeffs[1]*g11 + coeffs[2]*b11 + (1 << (ITUR_BT_601_SHIFT - 1)) + (16 << ITUR_BT_601_SHIFT);
-
- y[2*k + 0] = saturate_cast<uchar>(y00 >> ITUR_BT_601_SHIFT);
- y[2*k + 1] = saturate_cast<uchar>(y01 >> ITUR_BT_601_SHIFT);
- y[2*k + dst.step + 0] = saturate_cast<uchar>(y10 >> ITUR_BT_601_SHIFT);
- y[2*k + dst.step + 1] = saturate_cast<uchar>(y11 >> ITUR_BT_601_SHIFT);
+ const uchar* row0 = src_.ptr<uchar>(2 * i);
+ const uchar* row1 = src_.ptr<uchar>(2 * i + 1);
- int u00 = coeffs[3]*r00 + coeffs[4]*g00 + coeffs[5]*b00 + (1 << (ITUR_BT_601_SHIFT - 1)) + (128 << ITUR_BT_601_SHIFT);
- int v00 = coeffs[5]*r00 + coeffs[6]*g00 + coeffs[7]*b00 + (1 << (ITUR_BT_601_SHIFT - 1)) + (128 << ITUR_BT_601_SHIFT);
+ uchar* y = dst_->ptr<uchar>(2*i);
+ uchar* u = dst_->ptr<uchar>(h + i/2) + (i % 2) * (w/2);
+ uchar* v = dst_->ptr<uchar>(h + (i + h/2)/2) + ((i + h/2) % 2) * (w/2);
+ if( uIdx_ == 2 ) std::swap(u, v);
- u[k] = saturate_cast<uchar>(u00 >> ITUR_BT_601_SHIFT);
- v[k] = saturate_cast<uchar>(v00 >> ITUR_BT_601_SHIFT);
+ for( int j = 0, k = 0; j < w * cn; j += 2 * cn, k++ )
+ {
+ int r00 = row0[2-bIdx + j]; int g00 = row0[1 + j]; int b00 = row0[bIdx + j];
+ int r01 = row0[2-bIdx + cn + j]; int g01 = row0[1 + cn + j]; int b01 = row0[bIdx + cn + j];
+ int r10 = row1[2-bIdx + j]; int g10 = row1[1 + j]; int b10 = row1[bIdx + j];
+ int r11 = row1[2-bIdx + cn + j]; int g11 = row1[1 + cn + j]; int b11 = row1[bIdx + cn + j];
+
+ const int shifted16 = (16 << ITUR_BT_601_SHIFT);
+ const int halfShift = (1 << (ITUR_BT_601_SHIFT - 1));
+ int y00 = ITUR_BT_601_CRY * r00 + ITUR_BT_601_CGY * g00 + ITUR_BT_601_CBY * b00 + halfShift + shifted16;
+ int y01 = ITUR_BT_601_CRY * r01 + ITUR_BT_601_CGY * g01 + ITUR_BT_601_CBY * b01 + halfShift + shifted16;
+ int y10 = ITUR_BT_601_CRY * r10 + ITUR_BT_601_CGY * g10 + ITUR_BT_601_CBY * b10 + halfShift + shifted16;
+ int y11 = ITUR_BT_601_CRY * r11 + ITUR_BT_601_CGY * g11 + ITUR_BT_601_CBY * b11 + halfShift + shifted16;
+
+ y[2*k + 0] = saturate_cast<uchar>(y00 >> ITUR_BT_601_SHIFT);
+ y[2*k + 1] = saturate_cast<uchar>(y01 >> ITUR_BT_601_SHIFT);
+ y[2*k + dst_->step + 0] = saturate_cast<uchar>(y10 >> ITUR_BT_601_SHIFT);
+ y[2*k + dst_->step + 1] = saturate_cast<uchar>(y11 >> ITUR_BT_601_SHIFT);
+
+ const int shifted128 = (128 << ITUR_BT_601_SHIFT);
+ int u00 = ITUR_BT_601_CRU * r00 + ITUR_BT_601_CGU * g00 + ITUR_BT_601_CBU * b00 + halfShift + shifted128;
+ int v00 = ITUR_BT_601_CBU * r00 + ITUR_BT_601_CGV * g00 + ITUR_BT_601_CBV * b00 + halfShift + shifted128;
+
+ u[k] = saturate_cast<uchar>(u00 >> ITUR_BT_601_SHIFT);
+ v[k] = saturate_cast<uchar>(v00 >> ITUR_BT_601_SHIFT);
+ }
}
}
+
+ static bool isFit( const Mat& src )
+ {
+ return (src.total() >= 320*240);
+ }
+
+private:
+ RGB888toYUV420pInvoker& operator=(const RGB888toYUV420pInvoker&);
+
+ const Mat& src_;
+ Mat* const dst_;
+ const int uIdx_;
+};
+
+template<int bIdx, int uIdx>
+static void cvtRGBtoYUV420p(const Mat& src, Mat& dst)
+{
+ RGB888toYUV420pInvoker<bIdx> colorConverter(src, &dst, uIdx);
+ if( RGB888toYUV420pInvoker<bIdx>::isFit(src) )
+ parallel_for_(Range(0, src.rows/2), colorConverter);
+ else
+ colorConverter(Range(0, src.rows/2));
}
///////////////////////////////////// YUV422 -> RGB /////////////////////////////////////