I started loading EXR images using OpenEXR. I have to get RGB pixels using floating point type.
For RGB images, there was no problem loading while loading using this code:
ImfInputFile *iFile = ImfOpenInputFile(filename); FrameBuffer fb; const Header &iHeader = iFile.header(); bool hasRed = false, hasGreen = false, hasBlue = false; bool hasY = false; Box2i dw = iHeader.dataWindow(); int width = dw.max.x-dw.min.x+1; int height = dw.max.y-dw.min.y+1; for (ChannelList::ConstIterator it = iHeader.channels().begin(), ite = iHeader.channels().end(); it != ite; it++) { if ((strcmp(it.name(), "R") == 0)) { hasRed = true; } if ((strcmp(it.name(), "G") == 0)) { hasGreen = true; } if ((strcmp(it.name(), "B") == 0)) { hasBlue = true; } if (it.channel().type != HALF) { HDR_LOG("Unable to open EXR file \"%s\" (unsupported data type %s)", filename, it.channel().type); return (IEFileCantOpen); } } if ((hasRed == true) || (hasGreen == true) || (hasBlue == true)) { fb.insert("R", Slice( Imf::FLOAT, (char*)((char*)image->data + (sizeof(float) * 0)), sizeof(float) * 3, sizeof(float) * width * 3, 1, 1, 0.0 ) ); fb.insert("G", Slice( Imf::FLOAT, (char*)((char*)image->data + (sizeof(float) * 1)), sizeof(float) * 3, sizeof(float) * width * 3, 1, 1, 0.0 ) ); fb.insert("B", Slice( Imf::FLOAT, (char*)((char*)image->data + (sizeof(float) * 2)), sizeof(float) * 3, sizeof(float) * width * 3, 1, 1, 0.0 ) ); iFile.setFrameBuffer(fb); if (ReadImage(filename, iFile, dw.min.y, dw.max.y) == IEFileReadError) { HDR_LOG("There was a generic error on loading the EXR image \"%s\". Image could be corrupted.", filename); return (IEFileReadError); } image->unproc = 1; return (IENoError); } else { char sChannels[2048] = { '\0' }; for (ChannelList::ConstIterator it = iHeader.channels().begin(), ite = iHeader.channels().end(); it != ite; it++) { strcat(sChannels, it.name()); strcat(sChannels, " "); } HDR_LOG("Unable to open EXR file (unknown channels set: %s)", sChannels); return (IEFileReadError); } }
But I wonder how this library can decode / convert Y-RY-GY images (luminance + color channels) and receive RGB pixel data with a floating point.