static inline void
zero_ (ImageBuf &buf)
{
int chans = buf.nchannels();
for (ImageBuf::Iterator<T> pixel (buf); pixel.valid(); ++pixel)
for (int i = 0; i < chans; ++i)
pixel[i] = 0;
}
static inline void
setpixel_ (ImageBuf &buf, int x, int y, int z, const float *data, int chans)
{
ImageBuf::Iterator<T> pixel (buf, x, y, z);
if (pixel.valid()) {
for (int i = 0; i < chans; ++i)
pixel[i] = data[i];
}
}
static inline void
transfer_pixels_ (ImageBuf &buf, ColorTransfer *tfunc)
{
for (ImageBuf::Iterator<T> pixel (buf); pixel.valid(); ++pixel) {
convert_types (buf.spec().format, pixel.rawptr(),
buf.spec().format, pixel.rawptr(),
buf.nchannels(), tfunc,
buf.spec().alpha_channel, buf.spec().z_channel);
}
}
// Tests ImageBufAlgo::compare
void test_compare ()
{
std::cout << "test compare\n";
// Construct two identical 50% grey images
const int WIDTH = 10, HEIGHT = 10, CHANNELS = 3;
ImageSpec spec (WIDTH, HEIGHT, CHANNELS, TypeDesc::FLOAT);
ImageBuf A (spec);
ImageBuf B (spec);
const float grey[CHANNELS] = { 0.5, 0.5, 0.5 };
ImageBufAlgo::fill (A, grey);
ImageBufAlgo::fill (B, grey);
// Introduce some minor differences
const int NDIFFS = 10;
ImageBuf::Iterator<float> a (A);
for (int i = 0; i < NDIFFS && a.valid(); ++i, ++a) {
for (int c = 0; c < CHANNELS; ++c)
a[c] = a[c] + 0.01f * i;
}
// We expect the differences to be { 0, 0.01, 0.02, 0.03, 0.04, 0.05,
// 0.06, 0.07, 0.08, 0.09, 0, 0, ...}.
const float failthresh = 0.05;
const float warnthresh = 0.025;
ImageBufAlgo::CompareResults comp;
ImageBufAlgo::compare (A, B, failthresh, warnthresh, comp);
// We expect 5 pixels to exceed the fail threshold, 7 pixels to
// exceed the warn threshold, the maximum difference to be 0.09,
// and the maximally different pixel to be (9,0).
// The total error should be 3 chans * sum{0.01,...,0.09} / (pixels*chans)
// = 3 * 0.45 / (100*3) = 0.0045
std::cout << "Testing comparison: " << comp.nfail << " failed, "
<< comp.nwarn << " warned, max diff = " << comp.maxerror
<< " @ (" << comp.maxx << ',' << comp.maxy << ")\n";
std::cout << " mean err " << comp.meanerror << ", RMS err "
<< comp.rms_error << ", PSNR = " << comp.PSNR << "\n";
OIIO_CHECK_EQUAL (comp.nfail, 5);
OIIO_CHECK_EQUAL (comp.nwarn, 7);
OIIO_CHECK_EQUAL_THRESH (comp.maxerror, 0.09, 1e-6);
OIIO_CHECK_EQUAL (comp.maxx, 9);
OIIO_CHECK_EQUAL (comp.maxy, 0);
OIIO_CHECK_EQUAL_THRESH (comp.meanerror, 0.0045, 1.0e-8);
}
// DEPRECATED version
bool
ImageBufAlgo::add (ImageBuf &dst, const ImageBuf &A, const ImageBuf &B,
int options)
{
// Sanity checks
// dst must be distinct from A and B
if ((const void *)&A == (const void *)&dst ||
(const void *)&B == (const void *)&dst) {
dst.error ("destination image must be distinct from source");
return false;
}
// all three images must have the same number of channels
if (A.spec().nchannels != B.spec().nchannels) {
dst.error ("channel number mismatch: %d vs. %d",
A.spec().nchannels, B.spec().nchannels);
return false;
}
// If dst has not already been allocated, set it to the right size,
// make it unconditinally float
if (! dst.pixels_valid()) {
ImageSpec dstspec = A.spec();
dstspec.set_format (TypeDesc::TypeFloat);
dst.alloc (dstspec);
}
// Clear dst pixels if instructed to do so
if (options & ADD_CLEAR_DST) {
zero (dst);
}
ASSERT (A.spec().format == TypeDesc::FLOAT &&
B.spec().format == TypeDesc::FLOAT &&
dst.spec().format == TypeDesc::FLOAT);
ImageBuf::ConstIterator<float,float> a (A);
ImageBuf::ConstIterator<float,float> b (B);
ImageBuf::Iterator<float> d (dst);
int nchannels = A.nchannels();
// Loop over all pixels in A
for ( ; a.valid(); ++a) {
// Point the iterators for B and dst to the corresponding pixel
if (options & ADD_RETAIN_WINDOWS) {
b.pos (a.x(), a.y());
} else {
// ADD_ALIGN_WINDOWS: make B line up with A
b.pos (a.x()-A.xbegin()+B.xbegin(), a.y()-A.ybegin()+B.ybegin());
}
d.pos (a.x(), b.y());
if (! b.valid() || ! d.valid())
continue; // Skip pixels that don't align
// Add the pixel
for (int c = 0; c < nchannels; ++c)
d[c] = a[c] + b[c];
}
return true;
}