int main(void)
{
static const unsigned char answers[COLS] = { 31, 32, 34, 35, 36 };
unsigned long x;
for (x = 0; x < sizeof(p)/sizeof(p[0]); x++) {
p[x].b = (x + 34) | 1;
}
for (x = 0; x < columns; x++) {
double total_r = 0, total_g = 0, total_b = 0;
double saved_r = 0, saved_g = 0, saved_b = 0;
Minify(2*x + 0, 3.0);
Minify(2*x + 1, 7.0);
Minify(2*x + 2, 7.0);
saved_r = total_r;
saved_g = total_g;
Minify(2*x + 11, 15.0);
Minify(2*x + 12, 7.0);
Minify(2*x + 18, 7.0);
Minify(2*x + 19, 15.0);
Minify(2*x + 20, 15.0);
Minify(2*x + 21, 7.0);
q[x].r = (unsigned char)(total_r/128.0 + 0.5);
q[x].g = (unsigned char)(total_g/128.0 + 0.5);
q[x].b = (unsigned char)(total_b/128.0 + 0.5);
fprintf(stderr, "r:%f g:%f b:%f\n", saved_r, saved_g, saved_b);
}
for (x = 0; x < COLS; x++) {
if (answers[x] != q[x].b)
abort();
}
return 0;
}
unsigned long *HalfImage(unsigned long *image,int colums,int rows)
{
#define Minify(weight) \
total.red+=(weight)*(r->red); \
total.green+=(weight)*(r->green); \
total.blue+=(weight)*(r->blue); \
total.opacity+=(weight)*(r->opacity); \
r++;
unsigned long *minify_image;
long y;
/*
Initialize minified image.
*/
minify_image= image;
/*
Reduce each row.
*/
{
unsigned long row_count=0,zero=0;
float red,green,blue,opacity;
zero=0;
for (y=0; y < (long) minify_image->rows; y++)
{
DoublePixelPacket
total;
register const PixelPacket
*p,
*r;
register long
x;
register PixelPacket
*q;
MagickBool
thread_status;
p=AcquireImagePixels(image,-2,2*(y-1),image->columns+4,4,exception);
q=SetImagePixelsEx(minify_image,0,y,minify_image->columns,1,exception);
for (x=0; x < columns/2; x++)
{
/*
Compute weighted average of target pixel color components.
*/
total=zero;
r=p;
Minify(3.0); Minify(7.0); Minify(7.0); Minify(3.0);
r=p+(image->columns+4);
Minify(7.0); Minify(15.0); Minify(15.0); Minify(7.0);
r=p+2*(image->columns+4);
Minify(7.0); Minify(15.0); Minify(15.0); Minify(7.0);
r=p+3*(image->columns+4);
Minify(3.0); Minify(7.0); Minify(7.0); Minify(3.0);
q->red=(Quantum) (total.red/128.0+0.5);
q->green=(Quantum) (total.green/128.0+0.5);
q->blue=(Quantum) (total.blue/128.0+0.5);
q->opacity=(Quantum) (total.opacity/128.0+0.5);
p+=2;
q++;
}
if (!SyncImagePixelsEx(minify_image,exception))
thread_status=MagickFail;
#if defined(HAVE_OPENMP)
# pragma omp critical (GM_MinifyImage)
#endif
{
row_count++;
if (QuantumTick(row_count,image->rows))
if (!MagickMonitorFormatted(row_count,image->rows,exception,
MinifyImageText,image->filename))
thread_status=MagickFail;
if (thread_status == MagickFail)
status=MagickFail;
}
}
}
minify_image->is_grayscale=image->is_grayscale;
return(minify_image);
}