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Diffstat (limited to 'plugins/FreeImage/src/FreeImageToolkit/BSplineRotate.cpp')
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diff --git a/plugins/FreeImage/src/FreeImageToolkit/BSplineRotate.cpp b/plugins/FreeImage/src/FreeImageToolkit/BSplineRotate.cpp new file mode 100644 index 0000000000..e4be1d0bd2 --- /dev/null +++ b/plugins/FreeImage/src/FreeImageToolkit/BSplineRotate.cpp @@ -0,0 +1,730 @@ +// ========================================================== +// Bitmap rotation using B-Splines +// +// Design and implementation by +// - Philippe Thévenaz (philippe.thevenaz@epfl.ch) +// Adaptation for FreeImage by +// - Hervé Drolon (drolon@infonie.fr) +// +// This file is part of FreeImage 3 +// +// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY +// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES +// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE +// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED +// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT +// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY +// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL +// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER +// THIS DISCLAIMER. +// +// Use at your own risk! +// ========================================================== + +/* +========================================================== +This code was taken and adapted from the following reference : + +[1] Philippe Thévenaz, Spline interpolation, a C source code +implementation. http://bigwww.epfl.ch/thevenaz/ + +It implements ideas described in the following papers : + +[2] Unser M., Splines: A Perfect Fit for Signal and Image Processing. +IEEE Signal Processing Magazine, vol. 16, no. 6, pp. 22-38, November 1999. + +[3] Unser M., Aldroubi A., Eden M., B-Spline Signal Processing: Part I--Theory. +IEEE Transactions on Signal Processing, vol. 41, no. 2, pp. 821-832, February 1993. + +[4] Unser M., Aldroubi A., Eden M., B-Spline Signal Processing: Part II--Efficient Design and Applications. +IEEE Transactions on Signal Processing, vol. 41, no. 2, pp. 834-848, February 1993. + +========================================================== +*/ + + +#include <float.h> +#include "FreeImage.h" +#include "Utilities.h" + +#define PI ((double)3.14159265358979323846264338327950288419716939937510) + +#define ROTATE_QUADRATIC 2L // Use B-splines of degree 2 (quadratic interpolation) +#define ROTATE_CUBIC 3L // Use B-splines of degree 3 (cubic interpolation) +#define ROTATE_QUARTIC 4L // Use B-splines of degree 4 (quartic interpolation) +#define ROTATE_QUINTIC 5L // Use B-splines of degree 5 (quintic interpolation) + + +///////////////////////////////////////////////////////////////////////////////////////////////////////////// +// Prototypes definition + +static void ConvertToInterpolationCoefficients(double *c, long DataLength, double *z, long NbPoles, double Tolerance); +static double InitialCausalCoefficient(double *c, long DataLength, double z, double Tolerance); +static void GetColumn(double *Image, long Width, long x, double *Line, long Height); +static void GetRow(double *Image, long y, double *Line, long Width); +static double InitialAntiCausalCoefficient(double *c, long DataLength, double z); +static void PutColumn(double *Image, long Width, long x, double *Line, long Height); +static void PutRow(double *Image, long y, double *Line, long Width); +static bool SamplesToCoefficients(double *Image, long Width, long Height, long spline_degree); +static double InterpolatedValue(double *Bcoeff, long Width, long Height, double x, double y, long spline_degree); + +static FIBITMAP * Rotate8Bit(FIBITMAP *dib, double angle, double x_shift, double y_shift, double x_origin, double y_origin, long spline_degree, BOOL use_mask); + +///////////////////////////////////////////////////////////////////////////////////////////////////////////// +// Coefficients routines + +/** + ConvertToInterpolationCoefficients + + @param c Input samples --> output coefficients + @param DataLength Number of samples or coefficients + @param z Poles + @param NbPoles Number of poles + @param Tolerance Admissible relative error +*/ +static void +ConvertToInterpolationCoefficients(double *c, long DataLength, double *z, long NbPoles, double Tolerance) { + double Lambda = 1; + long n, k; + + // special case required by mirror boundaries + if(DataLength == 1L) { + return; + } + // compute the overall gain + for(k = 0L; k < NbPoles; k++) { + Lambda = Lambda * (1.0 - z[k]) * (1.0 - 1.0 / z[k]); + } + // apply the gain + for (n = 0L; n < DataLength; n++) { + c[n] *= Lambda; + } + // loop over all poles + for (k = 0L; k < NbPoles; k++) { + // causal initialization + c[0] = InitialCausalCoefficient(c, DataLength, z[k], Tolerance); + // causal recursion + for (n = 1L; n < DataLength; n++) { + c[n] += z[k] * c[n - 1L]; + } + // anticausal initialization + c[DataLength - 1L] = InitialAntiCausalCoefficient(c, DataLength, z[k]); + // anticausal recursion + for (n = DataLength - 2L; 0 <= n; n--) { + c[n] = z[k] * (c[n + 1L] - c[n]); + } + } +} + +/** + InitialCausalCoefficient + + @param c Coefficients + @param DataLength Number of coefficients + @param z Actual pole + @param Tolerance Admissible relative error + @return +*/ +static double +InitialCausalCoefficient(double *c, long DataLength, double z, double Tolerance) { + double Sum, zn, z2n, iz; + long n, Horizon; + + // this initialization corresponds to mirror boundaries + Horizon = DataLength; + if(Tolerance > 0) { + Horizon = (long)ceil(log(Tolerance) / log(fabs(z))); + } + if(Horizon < DataLength) { + // accelerated loop + zn = z; + Sum = c[0]; + for (n = 1L; n < Horizon; n++) { + Sum += zn * c[n]; + zn *= z; + } + return(Sum); + } + else { + // full loop + zn = z; + iz = 1.0 / z; + z2n = pow(z, (double)(DataLength - 1L)); + Sum = c[0] + z2n * c[DataLength - 1L]; + z2n *= z2n * iz; + for (n = 1L; n <= DataLength - 2L; n++) { + Sum += (zn + z2n) * c[n]; + zn *= z; + z2n *= iz; + } + return(Sum / (1.0 - zn * zn)); + } +} + +/** + GetColumn + + @param Image Input image array + @param Width Width of the image + @param x x coordinate of the selected line + @param Line Output linear array + @param Height Length of the line +*/ +static void +GetColumn(double *Image, long Width, long x, double *Line, long Height) { + long y; + + Image = Image + x; + for(y = 0L; y < Height; y++) { + Line[y] = (double)*Image; + Image += Width; + } +} + +/** + GetRow + + @param Image Input image array + @param y y coordinate of the selected line + @param Line Output linear array + @param Width Length of the line +*/ +static void +GetRow(double *Image, long y, double *Line, long Width) { + long x; + + Image = Image + (y * Width); + for(x = 0L; x < Width; x++) { + Line[x] = (double)*Image++; + } +} + +/** + InitialAntiCausalCoefficient + + @param c Coefficients + @param DataLength Number of samples or coefficients + @param z Actual pole + @return +*/ +static double +InitialAntiCausalCoefficient(double *c, long DataLength, double z) { + // this initialization corresponds to mirror boundaries + return((z / (z * z - 1.0)) * (z * c[DataLength - 2L] + c[DataLength - 1L])); +} + +/** + PutColumn + + @param Image Output image array + @param Width Width of the image + @param x x coordinate of the selected line + @param Line Input linear array + @param Height Length of the line and height of the image +*/ +static void +PutColumn(double *Image, long Width, long x, double *Line, long Height) { + long y; + + Image = Image + x; + for(y = 0L; y < Height; y++) { + *Image = (double)Line[y]; + Image += Width; + } +} + +/** + PutRow + + @param Image Output image array + @param y y coordinate of the selected line + @param Line Input linear array + @param Width length of the line and width of the image +*/ +static void +PutRow(double *Image, long y, double *Line, long Width) { + long x; + + Image = Image + (y * Width); + for(x = 0L; x < Width; x++) { + *Image++ = (double)Line[x]; + } +} + +/** + SamplesToCoefficients.<br> + Implement the algorithm that converts the image samples into B-spline coefficients. + This efficient procedure essentially relies on the three papers cited above; + data are processed in-place. + Even though this algorithm is robust with respect to quantization, + we advocate the use of a floating-point format for the data. + + @param Image Input / Output image (in-place processing) + @param Width Width of the image + @param Height Height of the image + @param spline_degree Degree of the spline model + @return Returns true if success, false otherwise +*/ +static bool +SamplesToCoefficients(double *Image, long Width, long Height, long spline_degree) { + double *Line; + double Pole[2]; + long NbPoles; + long x, y; + + // recover the poles from a lookup table + switch (spline_degree) { + case 2L: + NbPoles = 1L; + Pole[0] = sqrt(8.0) - 3.0; + break; + case 3L: + NbPoles = 1L; + Pole[0] = sqrt(3.0) - 2.0; + break; + case 4L: + NbPoles = 2L; + Pole[0] = sqrt(664.0 - sqrt(438976.0)) + sqrt(304.0) - 19.0; + Pole[1] = sqrt(664.0 + sqrt(438976.0)) - sqrt(304.0) - 19.0; + break; + case 5L: + NbPoles = 2L; + Pole[0] = sqrt(135.0 / 2.0 - sqrt(17745.0 / 4.0)) + sqrt(105.0 / 4.0) + - 13.0 / 2.0; + Pole[1] = sqrt(135.0 / 2.0 + sqrt(17745.0 / 4.0)) - sqrt(105.0 / 4.0) + - 13.0 / 2.0; + break; + default: + // Invalid spline degree + return false; + } + + // convert the image samples into interpolation coefficients + + // in-place separable process, along x + Line = (double *)malloc(Width * sizeof(double)); + if (Line == NULL) { + // Row allocation failed + return false; + } + for (y = 0L; y < Height; y++) { + GetRow(Image, y, Line, Width); + ConvertToInterpolationCoefficients(Line, Width, Pole, NbPoles, DBL_EPSILON); + PutRow(Image, y, Line, Width); + } + free(Line); + + // in-place separable process, along y + Line = (double *)malloc(Height * sizeof(double)); + if (Line == NULL) { + // Column allocation failed + return false; + } + for (x = 0L; x < Width; x++) { + GetColumn(Image, Width, x, Line, Height); + ConvertToInterpolationCoefficients(Line, Height, Pole, NbPoles, DBL_EPSILON); + PutColumn(Image, Width, x, Line, Height); + } + free(Line); + + return true; +} + +///////////////////////////////////////////////////////////////////////////////////////////////////////////// +// Interpolation routines + +/** +Perform the bidimensional interpolation of an image. +Given an array of spline coefficients, return the value of +the underlying continuous spline model, sampled at the location (x, y). +The model degree can be 2 (quadratic), 3 (cubic), 4 (quartic), or 5 (quintic). + +@param Bcoeff Input B-spline array of coefficients +@param Width Width of the image +@param Height Height of the image +@param x x coordinate where to interpolate +@param y y coordinate where to interpolate +@param spline_degree Degree of the spline model +@return Returns the value of the underlying continuous spline model, +sampled at the location (x, y) +*/ +static double +InterpolatedValue(double *Bcoeff, long Width, long Height, double x, double y, long spline_degree) { + double *p; + double xWeight[6], yWeight[6]; + double interpolated; + double w, w2, w4, t, t0, t1; + long xIndex[6], yIndex[6]; + long Width2 = 2L * Width - 2L, Height2 = 2L * Height - 2L; + long i, j, k; + + // compute the interpolation indexes + if (spline_degree & 1L) { + i = (long)floor(x) - spline_degree / 2L; + j = (long)floor(y) - spline_degree / 2L; + for(k = 0; k <= spline_degree; k++) { + xIndex[k] = i++; + yIndex[k] = j++; + } + } + else { + i = (long)floor(x + 0.5) - spline_degree / 2L; + j = (long)floor(y + 0.5) - spline_degree / 2L; + for (k = 0; k <= spline_degree; k++) { + xIndex[k] = i++; + yIndex[k] = j++; + } + } + + // compute the interpolation weights + switch (spline_degree) { + case 2L: + /* x */ + w = x - (double)xIndex[1]; + xWeight[1] = 3.0 / 4.0 - w * w; + xWeight[2] = (1.0 / 2.0) * (w - xWeight[1] + 1.0); + xWeight[0] = 1.0 - xWeight[1] - xWeight[2]; + /* y */ + w = y - (double)yIndex[1]; + yWeight[1] = 3.0 / 4.0 - w * w; + yWeight[2] = (1.0 / 2.0) * (w - yWeight[1] + 1.0); + yWeight[0] = 1.0 - yWeight[1] - yWeight[2]; + break; + case 3L: + /* x */ + w = x - (double)xIndex[1]; + xWeight[3] = (1.0 / 6.0) * w * w * w; + xWeight[0] = (1.0 / 6.0) + (1.0 / 2.0) * w * (w - 1.0) - xWeight[3]; + xWeight[2] = w + xWeight[0] - 2.0 * xWeight[3]; + xWeight[1] = 1.0 - xWeight[0] - xWeight[2] - xWeight[3]; + /* y */ + w = y - (double)yIndex[1]; + yWeight[3] = (1.0 / 6.0) * w * w * w; + yWeight[0] = (1.0 / 6.0) + (1.0 / 2.0) * w * (w - 1.0) - yWeight[3]; + yWeight[2] = w + yWeight[0] - 2.0 * yWeight[3]; + yWeight[1] = 1.0 - yWeight[0] - yWeight[2] - yWeight[3]; + break; + case 4L: + /* x */ + w = x - (double)xIndex[2]; + w2 = w * w; + t = (1.0 / 6.0) * w2; + xWeight[0] = 1.0 / 2.0 - w; + xWeight[0] *= xWeight[0]; + xWeight[0] *= (1.0 / 24.0) * xWeight[0]; + t0 = w * (t - 11.0 / 24.0); + t1 = 19.0 / 96.0 + w2 * (1.0 / 4.0 - t); + xWeight[1] = t1 + t0; + xWeight[3] = t1 - t0; + xWeight[4] = xWeight[0] + t0 + (1.0 / 2.0) * w; + xWeight[2] = 1.0 - xWeight[0] - xWeight[1] - xWeight[3] - xWeight[4]; + /* y */ + w = y - (double)yIndex[2]; + w2 = w * w; + t = (1.0 / 6.0) * w2; + yWeight[0] = 1.0 / 2.0 - w; + yWeight[0] *= yWeight[0]; + yWeight[0] *= (1.0 / 24.0) * yWeight[0]; + t0 = w * (t - 11.0 / 24.0); + t1 = 19.0 / 96.0 + w2 * (1.0 / 4.0 - t); + yWeight[1] = t1 + t0; + yWeight[3] = t1 - t0; + yWeight[4] = yWeight[0] + t0 + (1.0 / 2.0) * w; + yWeight[2] = 1.0 - yWeight[0] - yWeight[1] - yWeight[3] - yWeight[4]; + break; + case 5L: + /* x */ + w = x - (double)xIndex[2]; + w2 = w * w; + xWeight[5] = (1.0 / 120.0) * w * w2 * w2; + w2 -= w; + w4 = w2 * w2; + w -= 1.0 / 2.0; + t = w2 * (w2 - 3.0); + xWeight[0] = (1.0 / 24.0) * (1.0 / 5.0 + w2 + w4) - xWeight[5]; + t0 = (1.0 / 24.0) * (w2 * (w2 - 5.0) + 46.0 / 5.0); + t1 = (-1.0 / 12.0) * w * (t + 4.0); + xWeight[2] = t0 + t1; + xWeight[3] = t0 - t1; + t0 = (1.0 / 16.0) * (9.0 / 5.0 - t); + t1 = (1.0 / 24.0) * w * (w4 - w2 - 5.0); + xWeight[1] = t0 + t1; + xWeight[4] = t0 - t1; + /* y */ + w = y - (double)yIndex[2]; + w2 = w * w; + yWeight[5] = (1.0 / 120.0) * w * w2 * w2; + w2 -= w; + w4 = w2 * w2; + w -= 1.0 / 2.0; + t = w2 * (w2 - 3.0); + yWeight[0] = (1.0 / 24.0) * (1.0 / 5.0 + w2 + w4) - yWeight[5]; + t0 = (1.0 / 24.0) * (w2 * (w2 - 5.0) + 46.0 / 5.0); + t1 = (-1.0 / 12.0) * w * (t + 4.0); + yWeight[2] = t0 + t1; + yWeight[3] = t0 - t1; + t0 = (1.0 / 16.0) * (9.0 / 5.0 - t); + t1 = (1.0 / 24.0) * w * (w4 - w2 - 5.0); + yWeight[1] = t0 + t1; + yWeight[4] = t0 - t1; + break; + default: + // Invalid spline degree + return 0; + } + + // apply the mirror boundary conditions + for(k = 0; k <= spline_degree; k++) { + xIndex[k] = (Width == 1L) ? (0L) : ((xIndex[k] < 0L) ? + (-xIndex[k] - Width2 * ((-xIndex[k]) / Width2)) + : (xIndex[k] - Width2 * (xIndex[k] / Width2))); + if (Width <= xIndex[k]) { + xIndex[k] = Width2 - xIndex[k]; + } + yIndex[k] = (Height == 1L) ? (0L) : ((yIndex[k] < 0L) ? + (-yIndex[k] - Height2 * ((-yIndex[k]) / Height2)) + : (yIndex[k] - Height2 * (yIndex[k] / Height2))); + if (Height <= yIndex[k]) { + yIndex[k] = Height2 - yIndex[k]; + } + } + + // perform interpolation + interpolated = 0.0; + for(j = 0; j <= spline_degree; j++) { + p = Bcoeff + (yIndex[j] * Width); + w = 0.0; + for(i = 0; i <= spline_degree; i++) { + w += xWeight[i] * p[xIndex[i]]; + } + interpolated += yWeight[j] * w; + } + + return interpolated; +} + +///////////////////////////////////////////////////////////////////////////////////////////////////////////// +// FreeImage implementation + + +/** + Image translation and rotation using B-Splines. + + @param dib Input 8-bit greyscale image + @param angle Output image rotation in degree + @param x_shift Output image horizontal shift + @param y_shift Output image vertical shift + @param x_origin Output origin of the x-axis + @param y_origin Output origin of the y-axis + @param spline_degree Output degree of the B-spline model + @param use_mask Whether or not to mask the image + @return Returns the translated & rotated dib if successful, returns NULL otherwise +*/ +static FIBITMAP * +Rotate8Bit(FIBITMAP *dib, double angle, double x_shift, double y_shift, double x_origin, double y_origin, long spline_degree, BOOL use_mask) { + double *ImageRasterArray; + double p; + double a11, a12, a21, a22; + double x0, y0, x1, y1; + long x, y; + long spline; + bool bResult; + + int bpp = FreeImage_GetBPP(dib); + if(bpp != 8) { + return NULL; + } + + int width = FreeImage_GetWidth(dib); + int height = FreeImage_GetHeight(dib); + switch(spline_degree) { + case ROTATE_QUADRATIC: + spline = 2L; // Use splines of degree 2 (quadratic interpolation) + break; + case ROTATE_CUBIC: + spline = 3L; // Use splines of degree 3 (cubic interpolation) + break; + case ROTATE_QUARTIC: + spline = 4L; // Use splines of degree 4 (quartic interpolation) + break; + case ROTATE_QUINTIC: + spline = 5L; // Use splines of degree 5 (quintic interpolation) + break; + default: + spline = 3L; + } + + // allocate output image + FIBITMAP *dst = FreeImage_Allocate(width, height, bpp); + if (!dst) + return NULL; + // buid a grey scale palette + RGBQUAD *pal = FreeImage_GetPalette(dst); + for(int i = 0; i < 256; i++) { + pal[i].rgbRed = pal[i].rgbGreen = pal[i].rgbBlue = (BYTE)i; + } + + // allocate a temporary array + ImageRasterArray = (double*)malloc(width * height * sizeof(double)); + if (!ImageRasterArray) { + FreeImage_Unload(dst); + return NULL; + } + // copy data samples + for(y = 0; y < height; y++) { + double *pImage = &ImageRasterArray[y*width]; + BYTE *src_bits = FreeImage_GetScanLine(dib, height-1-y); + + for(x = 0; x < width; x++) { + pImage[x] = (double)src_bits[x]; + } + } + + // convert between a representation based on image samples + // and a representation based on image B-spline coefficients + bResult = SamplesToCoefficients(ImageRasterArray, width, height, spline); + if (!bResult) { + FreeImage_Unload(dst); + free(ImageRasterArray); + return NULL; + } + + // prepare the geometry + angle *= PI / 180.0; + a11 = cos(angle); + a12 = -sin(angle); + a21 = sin(angle); + a22 = cos(angle); + x0 = a11 * (x_shift + x_origin) + a12 * (y_shift + y_origin); + y0 = a21 * (x_shift + x_origin) + a22 * (y_shift + y_origin); + x_shift = x_origin - x0; + y_shift = y_origin - y0; + + // visit all pixels of the output image and assign their value + for(y = 0; y < height; y++) { + BYTE *dst_bits = FreeImage_GetScanLine(dst, height-1-y); + + x0 = a12 * (double)y + x_shift; + y0 = a22 * (double)y + y_shift; + + for(x = 0; x < width; x++) { + x1 = x0 + a11 * (double)x; + y1 = y0 + a21 * (double)x; + if(use_mask) { + if ((x1 <= -0.5) || (((double)width - 0.5) <= x1) || (y1 <= -0.5) || (((double)height - 0.5) <= y1)) { + p = 0; + } + else { + p = (double)InterpolatedValue(ImageRasterArray, width, height, x1, y1, spline); + } + } + else { + p = (double)InterpolatedValue(ImageRasterArray, width, height, x1, y1, spline); + } + // clamp and convert to BYTE + dst_bits[x] = (BYTE)MIN(MAX((int)0, (int)(p + 0.5)), (int)255); + } + } + + // free working array and return + free(ImageRasterArray); + + return dst; +} + +/** + Image rotation using a 3rd order (cubic) B-Splines. + + @param dib Input dib (8, 24 or 32-bit) + @param angle Output image rotation + @param x_shift Output image horizontal shift + @param y_shift Output image vertical shift + @param x_origin Output origin of the x-axis + @param y_origin Output origin of the y-axis + @param use_mask Whether or not to mask the image + @return Returns the translated & rotated dib if successful, returns NULL otherwise +*/ +FIBITMAP * DLL_CALLCONV +FreeImage_RotateEx(FIBITMAP *dib, double angle, double x_shift, double y_shift, double x_origin, double y_origin, BOOL use_mask) { + + int x, y, bpp; + int channel, nb_channels; + BYTE *src_bits, *dst_bits; + FIBITMAP *src8 = NULL, *dst8 = NULL, *dst = NULL; + + if (!FreeImage_HasPixels(dib)) return NULL; + + try { + + bpp = FreeImage_GetBPP(dib); + + if(bpp == 8) { + FIBITMAP *dst_8 = Rotate8Bit(dib, angle, x_shift, y_shift, x_origin, y_origin, ROTATE_CUBIC, use_mask); + if(dst_8) { + // copy metadata from src to dst + FreeImage_CloneMetadata(dst_8, dib); + } + return dst_8; + } + if ((bpp == 24) || (bpp == 32)) { + // allocate dst image + int width = FreeImage_GetWidth(dib); + int height = FreeImage_GetHeight(dib); + if ( bpp == 24 ) { + dst = FreeImage_Allocate(width, height, bpp, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK); + } else { + dst = FreeImage_Allocate(width, height, bpp, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK); + } + if (!dst) throw(1); + + // allocate a temporary 8-bit dib (no need to build a palette) + src8 = FreeImage_Allocate(width, height, 8); + if (!src8) throw(1); + + // process each channel separately + // ------------------------------- + nb_channels = (bpp / 8); + + for(channel = 0; channel < nb_channels; channel++) { + // extract channel from source dib + for(y = 0; y < height; y++) { + src_bits = FreeImage_GetScanLine(dib, y); + dst_bits = FreeImage_GetScanLine(src8, y); + for(x = 0; x < width; x++) { + dst_bits[x] = src_bits[channel]; + src_bits += nb_channels; + } + } + + // process channel + dst8 = Rotate8Bit(src8, angle, x_shift, y_shift, x_origin, y_origin, ROTATE_CUBIC, use_mask); + if (!dst8) throw(1); + + // insert channel to destination dib + for(y = 0; y < height; y++) { + src_bits = FreeImage_GetScanLine(dst8, y); + dst_bits = FreeImage_GetScanLine(dst, y); + for(x = 0; x < width; x++) { + dst_bits[channel] = src_bits[x]; + dst_bits += nb_channels; + } + } + + FreeImage_Unload(dst8); + } + + FreeImage_Unload(src8); + + // copy metadata from src to dst + FreeImage_CloneMetadata(dst, dib); + + return dst; + } + } catch(int) { + if(src8) FreeImage_Unload(src8); + if(dst8) FreeImage_Unload(dst8); + if(dst) FreeImage_Unload(dst); + } + + return NULL; +} |