C++ Header::dataWindow方法代码示例

/** \brief Convert an OpenEXR header to our own header representation.
 *
 * \param exrHeader - input header
 * \param header - output header
 */
void convertHeader(const Imf::Header& exrHeader, CqTexFileHeader& header)
{
	// Set width, height
	const Imath::Box2i& dataBox = exrHeader.dataWindow();
	header.setWidth(dataBox.max.x - dataBox.min.x+1);
	header.setHeight(dataBox.max.y - dataBox.min.y+1);
	// display window
	const Imath::Box2i& displayBox = exrHeader.displayWindow();
	header.set<Attr::DisplayWindow>( SqImageRegion(
				displayBox.max.x - displayBox.min.x,
				displayBox.max.y - displayBox.min.y,
				displayBox.min.x - dataBox.min.x,
				displayBox.min.y - dataBox.min.y) );

	// Set tiling information ?

	// Aspect ratio
	header.set<Attr::PixelAspectRatio>(exrHeader.pixelAspectRatio());

	TqChannelNameMap channelNameMap;
	// Convert channel representation
	const Imf::ChannelList& exrChannels = exrHeader.channels();
	CqChannelList& channels = header.channelList();
	for(Imf::ChannelList::ConstIterator i = exrChannels.begin();
			i != exrChannels.end(); ++i)
	{
		// use lower case names for channels; OpenEXR uses upper case.
		std::string chanName = i.name();
		std::transform(chanName.begin(), chanName.end(), chanName.begin(),
				::tolower);
		channelNameMap[chanName] = i.name();
		channels.addChannel( SqChannelInfo(chanName,
				channelTypeFromExr(i.channel().type)) );
	}
	header.set<Attr::ExrChannelNameMap>(channelNameMap);
	channels.reorderChannels();

	// Set compresssion type
	header.set<Attr::Compression>(exrCompressionToString(exrHeader.compression()));
}

bool
OpenEXRInput::open (const std::string &name, ImageSpec &newspec)
{
    // Quick check to reject non-exr files
    bool tiled;
    if (! Imf::isOpenExrFile (name.c_str(), tiled))
        return false;

    m_spec = ImageSpec(); // Clear everything with default constructor
    
    // Unless otherwise specified, exr files are assumed to be linear.
    m_spec.attribute ("oiio:ColorSpace", "Linear");
    
    try {
        if (tiled) {
            m_input_tiled = new Imf::TiledInputFile (name.c_str());
            m_header = &(m_input_tiled->header());
        } else {
            m_input_scanline = new Imf::InputFile (name.c_str());
            m_header = &(m_input_scanline->header());
        }
    }
    catch (const std::exception &e) {
        error ("OpenEXR exception: %s", e.what());
        return false;
    }
    if (! m_input_scanline && ! m_input_tiled) {
        error ("Unknown error opening EXR file");
        return false;
    }

    Imath::Box2i datawindow = m_header->dataWindow();
    m_spec.x = datawindow.min.x;
    m_spec.y = datawindow.min.y;
    m_spec.z = 0;
    m_spec.width = datawindow.max.x - datawindow.min.x + 1;
    m_spec.height = datawindow.max.y - datawindow.min.y + 1;
    m_spec.depth = 1;
    m_topwidth = m_spec.width;      // Save top-level mipmap dimensions
    m_topheight = m_spec.height;
    Imath::Box2i displaywindow = m_header->displayWindow();
    m_spec.full_x = displaywindow.min.x;
    m_spec.full_y = displaywindow.min.y;
    m_spec.full_z = 0;
    m_spec.full_width = displaywindow.max.x - displaywindow.min.x + 1;
    m_spec.full_height = displaywindow.max.y - displaywindow.min.y + 1;
    m_spec.full_depth = 1;
    if (tiled) {
        m_spec.tile_width = m_input_tiled->tileXSize();
        m_spec.tile_height = m_input_tiled->tileYSize();
    } else {
        m_spec.tile_width = 0;
        m_spec.tile_height = 0;
    }
    m_spec.tile_depth = 1;
    query_channels ();   // also sets format

    m_nsubimages = 1;
    if (tiled) {
        // FIXME: levelmode
        m_levelmode = m_input_tiled->levelMode();
        m_roundingmode = m_input_tiled->levelRoundingMode();
        if (m_levelmode == Imf::MIPMAP_LEVELS) {
            m_nmiplevels = m_input_tiled->numLevels();
            m_spec.attribute ("openexr:roundingmode", m_roundingmode);
        } else if (m_levelmode == Imf::RIPMAP_LEVELS) {
            m_nmiplevels = std::max (m_input_tiled->numXLevels(),
                                     m_input_tiled->numYLevels());
            m_spec.attribute ("openexr:roundingmode", m_roundingmode);
        } else {
            m_nmiplevels = 1;
        }
    } else {
        m_levelmode = Imf::ONE_LEVEL;
        m_nmiplevels = 1;
    }

    const Imf::EnvmapAttribute *envmap;
    envmap = m_header->findTypedAttribute<Imf::EnvmapAttribute>("envmap");
    if (envmap) {
        m_cubeface = (envmap->value() == Imf::ENVMAP_CUBE);
        m_spec.attribute ("textureformat", m_cubeface ? "CubeFace Environment" : "LatLong Environment");
        // OpenEXR conventions for env maps
        if (! m_cubeface)
            m_spec.attribute ("oiio:updirection", "y");
        m_spec.attribute ("oiio:sampleborder", 1);
        // FIXME - detect CubeFace Shadow?
    } else {
        m_cubeface = false;
        if (tiled && m_levelmode == Imf::MIPMAP_LEVELS)
            m_spec.attribute ("textureformat", "Plain Texture");
        // FIXME - detect Shadow
    }

    const Imf::CompressionAttribute *compressattr;
    compressattr = m_header->findTypedAttribute<Imf::CompressionAttribute>("compression");
    if (compressattr) {
        const char *comp = NULL;
        switch (compressattr->value()) {
        case Imf::NO_COMPRESSION    : comp = "none"; break;
//.........这里部分代码省略.........

bool
OpenEXRInput::seek_subimage (int subimage, int miplevel, ImageSpec &newspec)
{
    if (subimage < 0 || subimage >= m_nsubimages)   // out of range
        return false;

    if (miplevel < 0 || miplevel >= m_nmiplevels)   // out of range
        return false;

    m_subimage = subimage;
    m_miplevel = miplevel;

    if (miplevel == 0 && m_levelmode == Imf::ONE_LEVEL) {
        newspec = m_spec;
        return true;
    }

    // Compute the resolution of the requested mip level.
    int w = m_topwidth, h = m_topheight;
    if (m_levelmode == Imf::MIPMAP_LEVELS) {
        while (miplevel--) {
            if (m_roundingmode == Imf::ROUND_DOWN) {
                w = w / 2;
                h = h / 2;
            } else {
                w = (w + 1) / 2;
                h = (h + 1) / 2;
            }
            w = std::max (1, w);
            h = std::max (1, h);
        }
    } else if (m_levelmode == Imf::RIPMAP_LEVELS) {
        // FIXME
    } else {
        ASSERT(0);
    }

    m_spec.width = w;
    m_spec.height = h;
    // N.B. OpenEXR doesn't support data and display windows per MIPmap
    // level.  So always take from the top level.
    Imath::Box2i datawindow = m_header->dataWindow();
    Imath::Box2i displaywindow = m_header->displayWindow();
    m_spec.x = datawindow.min.x;
    m_spec.y = datawindow.min.y;
    if (miplevel == 0) {
        m_spec.full_x = displaywindow.min.x;
        m_spec.full_y = displaywindow.min.y;
        m_spec.full_width = displaywindow.max.x - displaywindow.min.x + 1;
        m_spec.full_height = displaywindow.max.y - displaywindow.min.y + 1;
    } else {
        m_spec.full_x = m_spec.x;
        m_spec.full_y = m_spec.y;
        m_spec.full_width = m_spec.width;
        m_spec.full_height = m_spec.height;
    }
    if (m_cubeface) {
        m_spec.full_width = w;
        m_spec.full_height = w;
    }
    newspec = m_spec;

    return true;
}