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我正在开发一个适用于 Linux 的 C++ 图像查看器，它是使用 GTK+3 (gtkmm) 创建的用于 GUI 和 Magick++ 用于图像处理。我的目标是支持尽可能多的图像文件格式，包括动画 GIF。

获取 Magick++ 图像并将其绘制在 GTK+3 小部件中的最佳方法是什么，以便它适用于（几乎）任何图像文件格式？

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What is the best approach to take a Magick++ Image and draw it in a GTK+3 widget, such that it would work for (just about) any image file format?

As long as ImageMagick has the format delegate, you should be able to draw the GtkWidget image.

image = Gtk::manage(new Gtk::Image());
// Load image into ImageMagick
Magick::Image img("wizard:");
/// Calculate how much memory to allocate
size_t to_allocate = img.columns() * img.rows() * 3;
// Create a buffer
guint8 * buffer = new guint8[to_allocate];
// Write pixel data to buffer.
img.write(0, 0, img.columns(), img.rows(), "RGB", Magick::CharPixel, buffer);
// Build a Pixbuf from pixel data in memory.
Glib::RefPtr<Gdk::Pixbuf> pBuff = Gdk::Pixbuf::create_from_data(buffer, Gdk::COLORSPACE_RGB, false, 8, img.columns(), img.rows(), img.columns()*3 );
// Set GtkImage from Pixbuf
image->set(pBuff);

GtkImage from Magick++

Original Answer mixing C/C++ methods.

Use the following Magick++ method signature to export the pixel data into memory.

Magick::Image.write(const ssize_t x_,
                    const ssize_t y_,
                    const size_t columns_,
                    const size_t rows_,
                    const std::string &map_,           //<= Usually "RGB"
                    const StorageType type_,           //<= Usually CharType
                    void *pixels_)                     //<= Be sure to allocate _all_ the memory required (size of storage * number of channels * columns * rows)

Create a GdkPixBuf from the pixels exported above with the following GTK method.

GdkPixbuf *
gdk_pixbuf_new_from_bytes (GBytes *data,               //<= Same as pixels_.
                           GdkColorspace colorspace,   //<= Match colorspace channels from map_.
                           gboolean has_alpha,         //<= Usually no.
                           int bits_per_sample,        //<= Match StorageType bits
                           int width,                  //<= Same as columns_.
                           int height,                 //<= Same as rows_.
                           int rowstride);             //<= size of data-type * number of channel * width.

Finally, build a GtkImage from the PixBuf with the following method.

GtkWidget * gtk_image_new_from_pixbuf (GdkPixbuf *pixbuf);
于 2018-03-02T13:31:45.147 回答
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我想@emcconville 适合 ImageMagick 部分，因为我对此一无所知。

不过，对于 GTKmm 部分，您需要坚持使用 C++ API，因此请使用Gdk::Pixbuf::create_from_data从 ImageMagick 读取图像。

此外，在创建图像查看器时，您需要更改由Gtk::Image. 所以在启动时只需使用用Gtk::Image::Image（或 Glade 和）Gtk::Image创建的空图像，然后用Gtk::Image::set更改其中显示的图像，并将其传递给您的 pixbuf。Gtk::Builder

于 2018-03-02T14:57:13.837 回答