void edgeDetectSobel( const ChannelT<T> &srcChannel, const Area &srcArea, const Vec2i &dstLT, ChannelT<T> *dstChannel )
{
std::pair<Area,Vec2i> srcDst = clippedSrcDst( srcChannel.getBounds(), srcArea, dstChannel->getBounds(), dstLT );
const Area &area( srcDst.first );
const Vec2i &dstOffset( srcDst.second );
typename CHANTRAIT<T>::Sum sumX, sumY;
int32_t srcRowBytes = srcChannel.getRowBytes();
int8_t srcPixelBytes = srcChannel.getIncrement() * sizeof(T);
int8_t dstPixelBytes = dstChannel->getIncrement() * sizeof(T);
const T maxValue = CHANTRAIT<T>::max();
for( int32_t y = 1; y < area.getHeight() - 1; ++y ) {
const uint8_t *srcLine = reinterpret_cast<const uint8_t*>( srcChannel.getData( area.getX1() + 1, area.getY1() + y ) );
uint8_t *dstLine = reinterpret_cast<uint8_t*>( dstChannel->getData( dstOffset.x + area.getX1() + 1, dstOffset.y + y ) );
for( int32_t x = area.getX1() + 1; x < area.getX2() - 1; ++x ) {
// sumX = -srcLine[-srcRowPixels-srcPixelStride] + srcLine[-srcRowPixels+srcPixelStride] - 2 * srcLine[-srcPixelStride] + 2 * srcLine[srcPixelStride] - srcLine[srcRowPixels-srcPixelStride] + srcLine[srcRowPixels+srcPixelStride];
sumX = -*(T*)(srcLine-srcRowBytes-srcPixelBytes) + *(T*)(srcLine-srcRowBytes+srcPixelBytes) - 2 * *(T*)(srcLine-srcPixelBytes) + 2 * *(T*)(srcLine+srcPixelBytes) - *(T*)(srcLine+srcRowBytes-srcPixelBytes) + *(T*)(srcLine+srcRowBytes+srcPixelBytes);
// sumY = srcLine[-srcRowPixels-srcPixelStride] + 2 * srcLine[-srcRowPixels] + srcLine[-srcRowPixels + srcPixelStride] - srcLine[srcRowPixels-srcPixelStride] - 2 * srcLine[srcRowPixels] - srcLine[srcRowPixels+srcPixelStride];
sumY = *(T*)(srcLine-srcRowBytes-srcPixelBytes) + 2 * *(T*)(srcLine-srcRowBytes) + *(T*)(srcLine-srcRowBytes+srcPixelBytes) - *(T*)(srcLine+srcRowBytes-srcPixelBytes) - 2 * *(T*)(srcLine+srcPixelBytes) - *(T*)(srcLine+srcRowBytes+srcPixelBytes);
sumX = static_cast<typename CHANTRAIT<T>::Sum>( math<float>::sqrt( float( sumX * sumX + sumY * sumY ) ) );
if( sumX > maxValue ) sumX = maxValue;
*dstLine = static_cast<uint8_t>( sumX );
dstLine += dstPixelBytes;
srcLine += srcPixelBytes;
}
}
}
void flipVertical( const ChannelT<T> &srcChannel, ChannelT<T> *destChannel )
{
std::pair<Area,ivec2> srcDst = clippedSrcDst( srcChannel.getBounds(), destChannel->getBounds(), destChannel->getBounds(), ivec2(0,0) );
if( srcChannel.isPlanar() && destChannel->isPlanar() ) { // both channels are planar, so do a series of memcpy()'s
const int32_t srcPixelInc = srcChannel.getIncrement();
const size_t copyBytes = srcDst.first.getWidth() * srcPixelInc * sizeof(T);
for( int32_t y = 0; y < srcDst.first.getHeight(); ++y ) {
const T *srcPtr = srcChannel.getData( ivec2( 0, y ) );
T *dstPtr = destChannel->getData( ivec2( 0, srcDst.first.getHeight() - y - 1 ) );
memcpy( dstPtr, srcPtr, copyBytes );
}
}
else {
const int8_t srcInc = srcChannel.getIncrement();
const int8_t destInc = destChannel->getIncrement();
const int32_t width = srcDst.first.getWidth();
for( int y = 0; y < srcDst.first.getHeight(); ++y ) {
const T* src = srcChannel.getData( 0, y );
T* dest = destChannel->getData( 0, srcDst.first.getHeight() - 1 - y );
for ( int x = 0; x < width; ++x ) {
*dest = *src;
src += srcInc;
dest += destInc;
}
}
}
}
void thresholdImpl( const ChannelT<T> &srcChannel, T value, const Area &srcArea, const ivec2 &dstLT, ChannelT<T> *dstChannel )
{
std::pair<Area,ivec2> srcDst = clippedSrcDst( srcChannel.getBounds(), srcArea, dstChannel->getBounds(), dstLT );
const Area &area( srcDst.first );
const ivec2 &dstOffset( srcDst.second );
uint8_t srcInc = srcChannel.getIncrement();
uint8_t dstInc = dstChannel->getIncrement();
const T maxValue = CHANTRAIT<T>::max();
for( int32_t y = 0; y < area.getHeight(); ++y ) {
T *dstPtr = dstChannel->getData( ivec2( area.getX1(), y ) + dstOffset );
const T *srcPtr = srcChannel.getData( ivec2( area.getX1(), y ) );
for( int32_t x = area.getX1(); x < area.getX2(); ++x ) {
*dstPtr = ( *srcPtr > value ) ? maxValue : 0;
dstPtr += dstInc;
srcPtr += srcInc;
}
}
}
void ChannelT<T>::copyFrom( const ChannelT<T> &srcChannel, const Area &srcArea, const ivec2 &relativeOffset )
{
std::pair<Area,ivec2> srcDst = clippedSrcDst( srcChannel.getBounds(), srcArea, getBounds(), srcArea.getUL() + relativeOffset );
int32_t srcRowBytes = srcChannel.getRowBytes();
uint8_t srcIncrement = srcChannel.getIncrement();
uint8_t increment = mIncrement;
int32_t width = srcDst.first.getWidth();
for( int32_t y = 0; y < srcArea.getHeight(); ++y ) {
const T *src = reinterpret_cast<const T*>( reinterpret_cast<const uint8_t*>( srcChannel.mData + srcArea.x1 * srcIncrement ) + ( srcArea.y1 + y ) * srcRowBytes );
T *dst = reinterpret_cast<T*>( reinterpret_cast<uint8_t*>( mData + srcDst.second.x * mIncrement ) + ( y + srcDst.second.y ) * mRowBytes );
for( int32_t x = 0; x < width; ++x ) {
*dst = *src;
src += srcIncrement;
dst += increment;
}
}
}
void threshold( const ChannelT<T> &srcChannel, T value, ChannelT<T> *dstChannel )
{
thresholdImpl( srcChannel, value, srcChannel.getBounds(), ivec2(), dstChannel );
}
void edgeDetectSobel( const ChannelT<T> &srcChannel, ChannelT<T> *dstChannel )
{
edgeDetectSobel( srcChannel, srcChannel.getBounds(), Vec2i::zero(), dstChannel );
}