// Name: src/common/image.cpp
// Purpose: wxImage
// Author: Robert Roebling
-// RCS-ID: $Id$
// Copyright: (c) Robert Roebling
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
if ( old_width == width && old_height == height )
return *this;
- if (quality == wxIMAGE_QUALITY_HIGH)
- {
- quality = (width < old_width && height < old_height)
- ? wxIMAGE_QUALITY_BOX_AVERAGE
- : wxIMAGE_QUALITY_BICUBIC;
- }
-
// Resample the image using the method as specified.
switch ( quality )
{
case wxIMAGE_QUALITY_BOX_AVERAGE:
image = ResampleBox(width, height);
break;
+
+ case wxIMAGE_QUALITY_HIGH:
+ image = width < old_width && height < old_height
+ ? ResampleBox(width, height)
+ : ResampleBicubic(width, height);
+ break;
}
// If the original image has a mask, apply the mask to the new image
return image;
}
+namespace
+{
+
+struct BoxPrecalc
+{
+ int boxStart;
+ int boxEnd;
+};
+
+inline int BoxBetween(int value, int low, int high)
+{
+ return wxMax(wxMin(value, high), low);
+}
+
+void ResampleBoxPrecalc(wxVector<BoxPrecalc>& boxes, int oldDim)
+{
+ const int newDim = boxes.size();
+ const double scale_factor_1 = double(oldDim) / newDim;
+ const int scale_factor_2 = (int)(scale_factor_1 / 2);
+
+ for ( int dst = 0; dst < newDim; ++dst )
+ {
+ // Source pixel in the Y direction
+ const int src_p = int(dst * scale_factor_1);
+
+ BoxPrecalc& precalc = boxes[dst];
+ precalc.boxStart = BoxBetween(int(src_p - scale_factor_1/2.0 + 1),
+ 0, oldDim - 1);
+ precalc.boxEnd = BoxBetween(wxMax(precalc.boxStart + 1,
+ int(src_p + scale_factor_2)),
+ 0, oldDim - 1);
+ }
+}
+
+} // anonymous namespace
+
wxImage wxImage::ResampleBox(int width, int height) const
{
// This function implements a simple pre-blur/box averaging method for
wxImage ret_image(width, height, false);
- const double scale_factor_x = double(M_IMGDATA->m_width) / width;
- const double scale_factor_y = double(M_IMGDATA->m_height) / height;
+ wxVector<BoxPrecalc> vPrecalcs(height);
+ wxVector<BoxPrecalc> hPrecalcs(width);
+
+ ResampleBoxPrecalc(vPrecalcs, M_IMGDATA->m_height);
+ ResampleBoxPrecalc(hPrecalcs, M_IMGDATA->m_width);
- const int scale_factor_x_2 = (int)(scale_factor_x / 2);
- const int scale_factor_y_2 = (int)(scale_factor_y / 2);
const unsigned char* src_data = M_IMGDATA->m_data;
const unsigned char* src_alpha = M_IMGDATA->m_alpha;
for ( int y = 0; y < height; y++ ) // Destination image - Y direction
{
// Source pixel in the Y direction
- int src_y = (int)(y * scale_factor_y);
+ const BoxPrecalc& vPrecalc = vPrecalcs[y];
for ( int x = 0; x < width; x++ ) // Destination image - X direction
{
// Source pixel in the X direction
- int src_x = (int)(x * scale_factor_x);
+ const BoxPrecalc& hPrecalc = hPrecalcs[x];
// Box of pixels to average
averaged_pixels = 0;
sum_r = sum_g = sum_b = sum_a = 0.0;
- for ( int j = int(src_y - scale_factor_y/2.0 + 1), k = j;
- j <= int(src_y + scale_factor_y_2) || j < k + 2;
- j++ )
+ for ( int j = vPrecalc.boxStart; j <= vPrecalc.boxEnd; ++j )
{
- // We don't care to average pixels that don't exist (edges)
- if ( j < 0 || j > M_IMGDATA->m_height - 1 )
- continue;
-
- for ( int i = int(src_x - scale_factor_x/2.0 + 1), e = i;
- i <= src_x + scale_factor_x_2 || i < e + 2;
- i++ )
+ for ( int i = hPrecalc.boxStart; i <= hPrecalc.boxEnd; ++i )
{
- // Don't average edge pixels
- if ( i < 0 || i > M_IMGDATA->m_width - 1 )
- continue;
-
// Calculate the actual index in our source pixels
src_pixel_index = j * M_IMGDATA->m_width + i;
return ret_image;
}
+namespace
+{
+
+struct BilinearPrecalc
+{
+ int offset1;
+ int offset2;
+ double dd;
+ double dd1;
+};
+
+void ResampleBilinearPrecalc(wxVector<BilinearPrecalc>& precalcs, int oldDim)
+{
+ const int newDim = precalcs.size();
+ const double scale_factor = double(oldDim) / newDim;
+ const int srcpixmax = oldDim - 1;
+
+ for ( int dsty = 0; dsty < newDim; dsty++ )
+ {
+ // We need to calculate the source pixel to interpolate from - Y-axis
+ double srcpix = double(dsty) * scale_factor;
+ double srcpix1 = int(srcpix);
+ double srcpix2 = srcpix1 == srcpixmax ? srcpix1 : srcpix1 + 1.0;
+
+ BilinearPrecalc& precalc = precalcs[dsty];
+
+ precalc.dd = srcpix - (int)srcpix;
+ precalc.dd1 = 1.0 - precalc.dd;
+ precalc.offset1 = srcpix1 < 0.0
+ ? 0
+ : srcpix1 > srcpixmax
+ ? srcpixmax
+ : (int)srcpix1;
+ precalc.offset2 = srcpix2 < 0.0
+ ? 0
+ : srcpix2 > srcpixmax
+ ? srcpixmax
+ : (int)srcpix2;
+ }
+}
+
+} // anonymous namespace
+
wxImage wxImage::ResampleBilinear(int width, int height) const
{
// This function implements a Bilinear algorithm for resampling.
ret_image.SetAlpha();
dst_alpha = ret_image.GetAlpha();
}
- double HFactor = double(M_IMGDATA->m_height) / height;
- double WFactor = double(M_IMGDATA->m_width) / width;
-
- int srcpixymax = M_IMGDATA->m_height - 1;
- int srcpixxmax = M_IMGDATA->m_width - 1;
- double srcpixy, srcpixy1, srcpixy2, dy, dy1;
- double srcpixx, srcpixx1, srcpixx2, dx, dx1;
+ wxVector<BilinearPrecalc> vPrecalcs(height);
+ wxVector<BilinearPrecalc> hPrecalcs(width);
+ ResampleBilinearPrecalc(vPrecalcs, M_IMGDATA->m_height);
+ ResampleBilinearPrecalc(hPrecalcs, M_IMGDATA->m_width);
// initialize alpha values to avoid g++ warnings about possibly
// uninitialized variables
for ( int dsty = 0; dsty < height; dsty++ )
{
// We need to calculate the source pixel to interpolate from - Y-axis
- srcpixy = double(dsty) * HFactor;
- srcpixy1 = int(srcpixy);
- srcpixy2 = ( srcpixy1 == srcpixymax ) ? srcpixy1 : srcpixy1 + 1.0;
- dy = srcpixy - (int)srcpixy;
- dy1 = 1.0 - dy;
+ const BilinearPrecalc& vPrecalc = vPrecalcs[dsty];
+ const int y_offset1 = vPrecalc.offset1;
+ const int y_offset2 = vPrecalc.offset2;
+ const double dy = vPrecalc.dd;
+ const double dy1 = vPrecalc.dd1;
for ( int dstx = 0; dstx < width; dstx++ )
{
// X-axis of pixel to interpolate from
- srcpixx = double(dstx) * WFactor;
- srcpixx1 = int(srcpixx);
- srcpixx2 = ( srcpixx1 == srcpixxmax ) ? srcpixx1 : srcpixx1 + 1.0;
- dx = srcpixx - (int)srcpixx;
- dx1 = 1.0 - dx;
+ const BilinearPrecalc& hPrecalc = hPrecalcs[dstx];
- int x_offset1 = srcpixx1 < 0.0 ? 0 : srcpixx1 > srcpixxmax ? srcpixxmax : (int)srcpixx1;
- int x_offset2 = srcpixx2 < 0.0 ? 0 : srcpixx2 > srcpixxmax ? srcpixxmax : (int)srcpixx2;
- int y_offset1 = srcpixy1 < 0.0 ? 0 : srcpixy1 > srcpixymax ? srcpixymax : (int)srcpixy1;
- int y_offset2 = srcpixy2 < 0.0 ? 0 : srcpixy2 > srcpixymax ? srcpixymax : (int)srcpixy2;
+ const int x_offset1 = hPrecalc.offset1;
+ const int x_offset2 = hPrecalc.offset2;
+ const double dx = hPrecalc.dd;
+ const double dx1 = hPrecalc.dd1;
int src_pixel_index00 = y_offset1 * M_IMGDATA->m_width + x_offset1;
int src_pixel_index01 = y_offset1 * M_IMGDATA->m_width + x_offset2;
4 * spline_cube(value - 1)) / 6;
}
+
+namespace
+{
+
+struct BicubicPrecalc
+{
+ double weight[4];
+ int offset[4];
+};
+
+void ResampleBicubicPrecalc(wxVector<BicubicPrecalc> &aWeight, int oldDim)
+{
+ const int newDim = aWeight.size();
+ for ( int dstd = 0; dstd < newDim; dstd++ )
+ {
+ // We need to calculate the source pixel to interpolate from - Y-axis
+ const double srcpixd = static_cast<double>(dstd * oldDim) / newDim;
+ const double dd = srcpixd - static_cast<int>(srcpixd);
+
+ BicubicPrecalc &precalc = aWeight[dstd];
+
+ for ( int k = -1; k <= 2; k++ )
+ {
+ precalc.offset[k + 1] = srcpixd + k < 0.0
+ ? 0
+ : srcpixd + k >= oldDim
+ ? oldDim - 1
+ : static_cast<int>(srcpixd + k);
+
+ precalc.weight[k + 1] = spline_weight(k - dd);
+ }
+ }
+}
+
+} // anonymous namespace
+
// This is the bicubic resampling algorithm
wxImage wxImage::ResampleBicubic(int width, int height) const
{
dst_alpha = ret_image.GetAlpha();
}
+ // Precalculate weights
+ wxVector<BicubicPrecalc> vPrecalcs(height);
+ wxVector<BicubicPrecalc> hPrecalcs(width);
+
+ ResampleBicubicPrecalc(vPrecalcs, M_IMGDATA->m_height);
+ ResampleBicubicPrecalc(hPrecalcs, M_IMGDATA->m_width);
+
for ( int dsty = 0; dsty < height; dsty++ )
{
// We need to calculate the source pixel to interpolate from - Y-axis
- double srcpixy = double(dsty * M_IMGDATA->m_height) / height;
- double dy = srcpixy - (int)srcpixy;
+ const BicubicPrecalc& vPrecalc = vPrecalcs[dsty];
for ( int dstx = 0; dstx < width; dstx++ )
{
// X-axis of pixel to interpolate from
- double srcpixx = double(dstx * M_IMGDATA->m_width) / width;
- double dx = srcpixx - (int)srcpixx;
+ const BicubicPrecalc& hPrecalc = hPrecalcs[dstx];
// Sums for each color channel
double sum_r = 0, sum_g = 0, sum_b = 0, sum_a = 0;
for ( int k = -1; k <= 2; k++ )
{
// Y offset
- int y_offset = srcpixy + k < 0.0
- ? 0
- : srcpixy + k >= M_IMGDATA->m_height
- ? M_IMGDATA->m_height - 1
- : (int)(srcpixy + k);
+ const int y_offset = vPrecalc.offset[k + 1];
// Loop across the X axis
for ( int i = -1; i <= 2; i++ )
{
// X offset
- int x_offset = srcpixx + i < 0.0
- ? 0
- : srcpixx + i >= M_IMGDATA->m_width
- ? M_IMGDATA->m_width - 1
- : (int)(srcpixx + i);
+ const int x_offset = hPrecalc.offset[i + 1];
// Calculate the exact position where the source data
// should be pulled from based on the x_offset and y_offset
// Calculate the weight for the specified pixel according
// to the bicubic b-spline kernel we're using for
// interpolation
- double
- pixel_weight = spline_weight(i - dx)*spline_weight(k - dy);
+ const double
+ pixel_weight = vPrecalc.weight[k + 1] * hPrecalc.weight[i + 1];
// Create a sum of all velues for each color channel
// adjusted for the pixel's calculated weight
wxImage wxImage::ConvertToGreyscale(double weight_r, double weight_g, double weight_b) const
{
- wxImage image(MakeEmptyClone());
-
- wxCHECK( image.IsOk(), image );
-
- const unsigned char *src = M_IMGDATA->m_data;
- unsigned char *dest = image.GetData();
-
- const bool hasMask = M_IMGDATA->m_hasMask;
- const unsigned char maskRed = M_IMGDATA->m_maskRed;
- const unsigned char maskGreen = M_IMGDATA->m_maskGreen;
- const unsigned char maskBlue = M_IMGDATA->m_maskBlue;
+ wxImage image;
+ wxCHECK_MSG(IsOk(), image, "invalid image");
- const long size = M_IMGDATA->m_width * M_IMGDATA->m_height;
- for ( long i = 0; i < size; i++, src += 3, dest += 3 )
+ const int w = M_IMGDATA->m_width;
+ const int h = M_IMGDATA->m_height;
+ size_t size = size_t(w) * h;
+ image.Create(w, h, false);
+ const unsigned char* alpha = M_IMGDATA->m_alpha;
+ if (alpha)
{
- memcpy(dest, src, 3);
- // only modify non-masked pixels
- if ( !hasMask || src[0] != maskRed || src[1] != maskGreen || src[2] != maskBlue )
- {
- wxColour::MakeGrey(dest + 0, dest + 1, dest + 2, weight_r, weight_g, weight_b);
- }
+ image.SetAlpha();
+ memcpy(image.GetAlpha(), alpha, size);
}
-
- // copy the alpha channel, if any
- if ( image.HasAlpha() )
- {
- memcpy( image.GetAlpha(), GetAlpha(), GetWidth() * GetHeight() );
+ const unsigned char mask_r = M_IMGDATA->m_maskRed;
+ const unsigned char mask_g = M_IMGDATA->m_maskGreen;
+ const unsigned char mask_b = M_IMGDATA->m_maskBlue;
+ const bool hasMask = M_IMGDATA->m_hasMask;
+ if (hasMask)
+ image.SetMaskColour(mask_r, mask_g, mask_b);
+
+ const unsigned char* src = M_IMGDATA->m_data;
+ unsigned char* dst = image.GetData();
+ while (size--)
+ {
+ unsigned char r = *src++;
+ unsigned char g = *src++;
+ unsigned char b = *src++;
+ if (!hasMask || r != mask_r || g != mask_g || b != mask_b)
+ wxColour::MakeGrey(&r, &g, &b, weight_r, weight_g, weight_b);
+ *dst++ = r;
+ *dst++ = g;
+ *dst++ = b;
}
-
return image;
}
wxImage wxImage::ConvertToDisabled(unsigned char brightness) const
{
- wxImage image = *this;
-
- unsigned char mr = image.GetMaskRed();
- unsigned char mg = image.GetMaskGreen();
- unsigned char mb = image.GetMaskBlue();
-
- int width = image.GetWidth();
- int height = image.GetHeight();
- bool has_mask = image.HasMask();
+ wxImage image;
+ wxCHECK_MSG(IsOk(), image, "invalid image");
- for (int y = height-1; y >= 0; --y)
+ const int w = M_IMGDATA->m_width;
+ const int h = M_IMGDATA->m_height;
+ size_t size = size_t(w) * h;
+ image.Create(w, h, false);
+ const unsigned char* alpha = M_IMGDATA->m_alpha;
+ if (alpha)
{
- for (int x = width-1; x >= 0; --x)
- {
- unsigned char* data = image.GetData() + (y*(width*3))+(x*3);
- unsigned char* r = data;
- unsigned char* g = data+1;
- unsigned char* b = data+2;
-
- if (has_mask && (*r == mr) && (*g == mg) && (*b == mb))
- continue;
-
- wxColour::MakeDisabled(r, g, b, brightness);
- }
+ image.SetAlpha();
+ memcpy(image.GetAlpha(), alpha, size);
+ }
+ const unsigned char mask_r = M_IMGDATA->m_maskRed;
+ const unsigned char mask_g = M_IMGDATA->m_maskGreen;
+ const unsigned char mask_b = M_IMGDATA->m_maskBlue;
+ const bool hasMask = M_IMGDATA->m_hasMask;
+ if (hasMask)
+ image.SetMaskColour(mask_r, mask_g, mask_b);
+
+ const unsigned char* src = M_IMGDATA->m_data;
+ unsigned char* dst = image.GetData();
+ while (size--)
+ {
+ unsigned char r = *src++;
+ unsigned char g = *src++;
+ unsigned char b = *src++;
+ if (!hasMask || r != mask_r || g != mask_g || b != mask_b)
+ wxColour::MakeDisabled(&r, &g, &b, brightness);
+ *dst++ = r;
+ *dst++ = g;
+ *dst++ = b;
}
return image;
}
case BLUE:
hue = 4.0 + (red - green) / deltaRGB;
break;
-
- default:
- wxFAIL_MSG(wxT("hue not specified"));
- break;
}
hue /= 6.0;
projects / wxWidgets.git / blobdiff