dlib C++ Library - Old Release Notes

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- Version: 17.12

Last Modified: Nov 10, 2008

# Old Release Notes

# Release 17.2

Release date: Apr 21, 2008
Major Changes in this Release:

    New Stuff:
       - GUI Related
          - Added the scrollable_region widget
          - Added the text_grid widget
          - Added an event to the text_field so you can tell when the
            user modifies it.
          - Added the fit_to_contents() function to the tabbed_display
            widget.
       - Bayesian Network Related
          - Added the node_first_parent_assignment(), node_next_parent_assignment(),
            and node_cpt_filled_out() functions.

    Non-Backwards Compatible Changes:
       - Reverted the change in 17.0 where I made drawable::lastx and
         drawable::lasty not match the current location of the mouse inside
         the on_mouse_move() event.  I changed this back to how it was before,
         so now lastx and lasty represent the most current record of where
         the mouse is in *all* events.
       - Changed the functions that control text color in the label and text_field
         widgets to use rgb_pixel objects.  Also added a function to set the
         background color of a text_field.

    Bug fixes:
       - Fixed a bug in the bayesian_network_join_tree object that caused it to
         compute incorrect results for some networks.
       - GUI Related
          - Fixed a minor bug in the cursor drawing of the text_field
            gui widget.
          - Fixed a bug in the compute_cursor_rect() function.  It would return an
            incorrectly positioned rectangle for 0 length strings.
          - Changed the way wchar_t is handled in the serialize.h file.  Now
            everything should compile correctly in visual studio regardless of how
            you set the /Zc:wchar_t compiler option.
          - Fixed a bug in the menu_bar widget.  One of the members wasn't being
            initialized when it needed to be.
          - Fixed a bug in the tabbed_display where it didn't redraw itself
            correctly after it was moved by set_pos()

    Other:
       - Changed the xml parser so that it counts line numbers
         from the start of the input stream instead of from the
         root tag.
       - Changed the xml parser so that you will only get the fatal_error
         event once if it occurs.

# Release 17.1

Release date: Apr 13, 2008
Major Changes in this Release:

    New Stuff:
       - Added a zoomable_region widget
       - Added a directed_graph_drawer widget

    Non-Backwards Compatible Changes:
       - Changed the first_pixel argument of the draw_string() function
         to be a rectangle like all the other draw functions now use.

    Bug fixes:
       - Fixed a bug in the tooltip widget that was triggered when calling
         its member functions without calling set_tooltip_text().  This also
         fixed a bug in the button object that triggered when calling some button
         functions that referenced the tooltip widget.
       - Fixed a problem in the draw_circle and draw_solid_circle functions.
         They didn't draw themselves quite correctly in all cases.

    Other:

# Release 17.0

Release date: Apr 07, 2008
Major Changes in this Release:

    New Stuff:
      - Added a png_loader object
      - GUI related
        - Added a popup_menu widget
        - Added a menu_bar widget
        - Added a tooltip widget
        - Added a user selectable style to the gui button.
        - Added the draw_rounded_rectangle() and fill_gradient_rounded() functions
        - Added the mouse_over_event object to the base_widgets and made the
          button_action inherit from it.
        - Added the drawable::next_free_user_event_number() function
      - matrix and geometry:
        - Added a size() function to matrix_exp and matrix_ref objects.
        - Added a class that represents 2D points
        - Added the following matrix functions:
          - squared(), cubed(), get_rect(), a subm() function that takes
            rectangles, and normalize()
        - Added the following rectangle functions:
          - area(), centered_rect(), translate_rect(), move_rect(), resize_rect(),
            resize_rect_height(), resize_rect_width(), and nearest_point()

    Non-Backwards Compatible Changes:
      - Renamed atom() to array_to_matrix()
      - Moved the rectangle object from the gui_core into a new geometry folder
        (only matters if you were directly including the rectangle file)
      - Moved the vector object into the geometry folder.  Also removed the kernel_1a
        stuff.  So there is now only one possible vector implementation.
      - Changed the default position for a rectangle to (0,0) instead of (1,1)
      - Added edge data to the directed_graph.  This breaks backwards compatibility
        with the previous serialization format for directed_graphs.
      - GUI related:
        - Changed the base_window::on_keydown event signature so that it now
          reports more keyboard modifier keys (e.g. alt)
        - Made the functions for drawing on canvas objects take points and pixels
          instead of just a bunch of integers.  Also changed the order of the
          arguments so that the canvas comes first, followed by the location
          to draw on, then what to draw.
        - Moved the canvas drawing functions into the gui_widgets/canvas_drawing.h
          file.
        - Modified the drawable_window so that the drawable::lastx and drawable::lasty
          fields are updated after calls to on_mouse_move.  This way the x and y that
          go into the on_mouse_move actually tell you something.

    Bug fixes:
      - Fixed a bug in the floating point serialization code.  It
        didn't handle NaN or infinities correctly.
      - Fixed a bug in the win32 version of the gui_core component.  It was
        possible that calling set_size(), set_pos(), or set_title() could cause
        the program to deadlock.
      - Made the load_bmp() function more robust in the face of weirdly
        written BMP files.
      - Modified the draw_circle() and draw_solid_circle() functions so that they
        only touch each canvas pixel once.  This avoids messing up alpha blending
        if an rgb_alpha_pixel is used.

    Other:
      - Removed the old win32 only gui code in the dlib/gui folder.
      - Changed the default GUI font to a nicer Sans Serif font

# Release 16.5

Release date: Mar 04, 2008
Major Changes in this Release:

    New Stuff:
       - Added another constructor to the thread_function object.
         Now it can take proper function objects as well as normal function
         pointers.
       - Added the probabilistic_decision_function object and svm_nu_train_prob()
         function.

    Non-Backwards Compatible Changes:
       - Changed the svm train functions so that the cache_size argument
         now measures the max number of megabytes of memory to use rather
         than number of kernel matrix rows to cache.  It's default
         value is now 200MB.
       - changed the type typedef in the SVM kernel function objects to
         be named sample_type instead of type.

    Bug fixes:
       - Fixed a bug in the trim, rtrim, and ltrim functions.  They
         didn't return empty strings when the input string contained all
         trim characters.
       - Fixed a bug in the decision_function's copy constructor

    Other:
       - Added an optimization to the working set selection for the svm training code.
         Now the algorithm will prefer to select indices that are in the kernel
         matrix cache when possible.
       - Fixed a problem with the chm documentation file where many of the links
         didn't work.
       - Made the support vector functions capable of operating with floats, doubles,
         and long doubles instead of just the double type.

# Release 16.4

Release date: Feb 22, 2008
Major Changes in this Release:

    New Stuff:
       - Added aversion of the draw_line() function for images.
       - Added the atom(), rowm(), colm(), and subm() matrix functions.
       - Added some push/pop_back() functions to the array object that are similar
         to the ones in the std::vector.
       - Added the std_vector_c class that wraps std::vector and checks its
         function's preconditions.
       - Added the polynomial_kernel object for use with the svm algorithm.

    Non-Backwards Compatible Changes:
       - Changed the svm_nu_cross_validate() function to return a vector
         of both the +1 and -1 cross validation accuracies.

    Bug fixes:
       - Fixed a bug in the list_box that caused it to not hide itself properly
         when told to do so.
       - Fixed canvas::fill() gui function so that it should work right
         on 64 bit platforms.

    Other:

# Release 16.3

Release date: Feb 12, 2008
Major Changes in this Release:

    New Stuff:
       - Added memory manager support to the matrix object.

    Non-Backwards Compatible Changes:
       - Made the assign_pixel() function saturate grayscale values bigger
         than the target pixel type can handle.  Previously it would just
         truncate the numbers.
       - Removed rand_kernel_1 and rand_kernel_2 because they gave very
         inferior results compared to rand_kernel_3.  I then renamed
         rand_kernel_3 to rand_kernel_1.
       - Renamed rand::get_random_number() to get_random_8bit_number() and also
         added a get_random_16bit_number() and get_random_32bit_number()
       - Added a checksum to compress_stream_kernel_1 and kernel_2.  This
         breaks backwards compatibility with the previous versions.  That is,
         the new implementations will complain that decompression fails if
         you give them data compressed with the old non-checksum version of
         the compression routines.
       - Removed the width() and height() functions from the array2d object.
         Now only the equivalent nc() and nr() member functions remain.
       - Changed array2d::set_size(width,height) to set_size(num_rows, num_cols).
         That is, I switched the order of the two arguments to this function.
         The reason for doing this is to make it have the same form as the
         set_size() member of the matrix object.  This way the usage of the
         set_size() member for these two very similar data structures is
         the same.  Hopefully this will reduce confusion rather than
         make things worse.

    Bug fixes:
       - Fixed a bug in the image_widget.  It didn't repaint the screen
         all the way if you gave it a smaller image to display.
       - Fixed a bug in the cat() function that caused the state of the queue
         to be broken if you called cat with an empty queue.
       - Made the queue_sort_1 use a better sorting algorithm.  In particular, it
         will not sort slowly for nearly sorted data.
       - Fixed a bug in the queue_kernel_2 object that caused it to not work
         correctly with the non-default memory managers.

    Other:
       - Added example code for the member_function_pointer as well as the matrix
         object.
       - Added some more regression tests and made some of the longer running
         ones execute a lot quicker.
       - Made the unit test suite easier to use.  Now tests just throw an exception
         to indicate an error rather than returning an error code.
       - Added an example program for the multi-layer perceptron neural network.

# Release 16.2

Release date: Jan 25, 2008
Major Changes in this Release:

    New Stuff:
       - Added the is_signed_type and is_unsigned_type templates
       - Image Processing stuff
          - Added the assign_all_pixels() function
          - Added the assign_border_pixels() function
          - Added the assign_pixel_intensity() function
          - Added the auto_threshold_image() function
          - Added the binary_union() function
          - Added the edge_orientation() function
          - Added the get_histogram() function
          - Added the get_pixel_intensity() function
          - Added the hysteresis_threshold() function
          - Added the sobel_edge_detector() function
          - Added the suppress_non_maximum_edges() function
          - Added the zero_border_pixels() function
          - Changed the pixel_traits structure so that it can support 8, 16, and 32
            bit grayscale pixels.

    Non-Backwards Compatible Changes:
       - Added more fields to the pixel_traits template so if you had defined your
         own pixel types you will need to update them.

    Bug fixes:
       - Fixed some compiler errors in Visual Studio 2008

    Other:
       - Generally tried to clean up the documentation and code in this release

# Release 16.1

Release date: Jan 1, 2008
Major Changes in this Release:

    New Stuff:
       - Added the randomize_samples() function
       - Added the set_main_font() and main_font() functions to the drawable object.
         So now the drawable widgets can use a user provided font.

    Non-Backwards Compatible Changes:
       - Made the named_rectangle object a little easier to use.  It now won't
         let you size it so small that it doesn't display its entire name.

    Bug fixes:
       - Fixed a bug in the svm_nu_train() function that caused a crash with
         some inputs.
       - Fixed a compile time error that occurred when compiling the bayesian
         network code in Mac OS X.
       - Fixed a bug in the compute_cursor_pos() function where it would
         return the incorrect value.

    Other:
       - Added an example showing how to use the svm functions.

# Release 16.0

Release date: Dec 10, 2007
Major Changes in this Release:

    New Stuff:
       - Added the left_substr() and right_substr() functions
       - Added the zero_extend_cast() function
       - Added the unsigned_type template
       - Added the uint8 typedef
       - Bayesian Network related
          - Added the assignment object
          - Added the bayes_node object
          - Added the joint_probability_table object
          - Added the conditional_probability_table object
          - Added the bayesian_network_gibbs_sampler object
            This object implements an algorithm that performs approximate inference
            in a Bayesian Network.
          - Added the bayesian_network_join_tree object
            This object implements an algorithm that performs exact inference
            in a Bayesian Network.
       - Set related
          - Added the set_intersection_size() function
          - Added the set_union() function
          - Added the set_intersection() function
          - Added the set_difference() function
       - Graph related
          - Added the graph object
          - Added the is_graph template
          - Added the is_directed_graph template
          - Added the create_moral_graph() function
          - Added the triangulate_graph_and_find_cliques() function
          - Added the graph_contains_length_one_cycle() function
          - Added the find_connected_nodes() function
          - Added the graph_is_connected() function
          - Added the is_clique() function
          - Added the is_maximal_clique() function
          - Added the copy_graph_structure() function
          - Added the create_join_tree() function
          - Added the is_join_tree() function
          - Added the edge() function
       - GUI related
          - Added the base_window::get_display_size() function
          - Added message_box_blocking()
          - Added the bdf_font object which is capable of loading BDF font files into
            the font object used by the gui_widgets
       - Better Unicode support
          - Added the basic_utf8_ifstream: An input stream that can read UTF-8 files
          - Added serialization support for wchar_t and std::wstring
          - Added the is_combining_char() function
          - Added the convert_utf8_to_utf32() function
          - Modified most of the string manipulation functions in dlib/string.h
            to work with any kind of character type
          - The gui widgets' font object now works with Unicode text (i.e. wchar_t
            and unichar strings) as well as with normal char data.

    Non-Backwards Compatible Changes:
       - The dlib/all_console.cpp and dlib/all_gui.cpp files have been deprecated
         in favor of a new file.  Now to build with dlib you simply add
         dlib/all/source.cpp to your project regardless of what type of project
         you are building.
       - The GUI program entry point, winmain(), has been removed.  You can now use
         the normal main() entry point or some other non-standard entry point
         provided by your compiler.
       - Renamed directed_graph::node::item to directed_graph::node::data

    Bug fixes:
       - Fixed some build issues in gcc 4.2 involving some uses of the std_allocator
       - Fixed some build issues in Visual Studio involving the dir_nav component
         and building with NO_MAKEFILE #defined.
       - Moved the #define that disables the old WinSock API into the sockets cpp
         file.  This should avoid conflicts with people who are using the old WinSock
         API.
       - Changed the tuple template slightly to avoid a bug in Visual Studio 7.1
         that caused a compile time error in some instances.

    Other:

# Release 15.12

Release date: Nov 18, 2007
Major Changes in this Release:

    New Stuff:
       - Added a destroy() function to the map, set, hash_map, and hash_set objects.
       - Added the tuple object
       - Added an overload of connect() that has a timeout
       - Added rand_kernel_3 as a random number generator that uses the Mersenne Twister
         algorithm.
       - Added the directed_graph object
       - Added the graph_contains_undirected_cycle() and graph_contains_directed_cycle()
         functions.
       - Added the std_allocator object.   It is a STL style allocator that can use
         the dlib memory manager objects.
       - std::string manipulation functions:
          - Added the cast_to_string() function.
          - Added the tolower() function
          - Added the toupper() function
          - Added the ltrim() function
          - Added the rtrim() function
          - Added the trim() function
          - Added the lpad() function
          - Added the rpad() function
          - Added the pad() function

    Non-Backwards Compatible Changes:
       - Changed the default logging level from LNONE to LERROR
       - Renamed the ASSERT macro to DLIB_ASSERT and CASSERT to DLIB_CASSERT.
         This rename avoids a conflict with a macro inside MFC.
       - Changed the logger so that settings are inherited when a new logger
         is instantiated rather than just having the new logger use the
         default settings.
       - Removed the logger::clear() function since it no longer really
         makes sense given the above change.
       - Removed the get_main_thread_id() function and replaced it with the
         is_dlib_thread() function.

    Bug fixes:
       - Pushed some things into cpp files because doing so avoids build and/or
         runtime errors on some platforms.

    Other:
       - Changed the string_cast() function so that it will recognize the words true
         and false as boolean values.  Also improved the error message inside the
         string_cast_error exception object.

# Release 15.11

Release date: Oct 25, 2007
Major Changes in this Release:

    New Stuff:
       - Added the covariance() function
       - Added the rgb_alpha_pixel pixel type and modified all relevant functions to
         support it.

    Non-Backwards Compatible Changes:
      - The GUI changes that are non-backwards compatible:
           - The alpha parameter is now an unsigned char instead of unsigned int
             and its range is now 0 to 255 instead of 0 to 256.
           - The image_widget no longer has any member functions dealing with
             alpha values.  If you want to use alpha blending you just give it an
             image that has an alpha channel.  The same goes for draw_image().
      - There are now more fields in the pixel_traits template.  So if you were
        defining your own pixels before you will need to update your pixel_traits
        specializations.

    Bug fixes:
      - Made some functions non-inline and put some things on the stack
        instead of heap.  Doing this avoids some problems with certain
        kinds of builds in visual studio.

    Other:
      - Modified the message_box() function so that it is safe to call end_program()
        from within its callback event.

# Release 15.10

Release date: Oct 09, 2007
Major Changes in this Release:

    New Stuff:
       - Modified the GUI drawing functions to take an alpha argument to allow
         alpha blending.
       - Added the svm_nu_cross_validate() function to perform k-fold
         cross validation using the svm_nu_train() function.
       - Added the boost enable_if templates
       - Added the rand_float extension to the rand object.
       - New matrix features:
          - Added the pinv() function
          - Changed round_zeros() to use the machine epsilon instead of 1e-6 as
            its default epsilon.
          - Modified the matrix object so that you can declare them with
            a static dimension and a dynamic dimension.  E.g. matrix<float,0,10>
            is now legal and declares a matrix with a fixed number of columns(10)
            and a variable number of rows.
          - Added the equal() function to compare two matrices of floating
            point numbers for near equality.
          - Changed the matrix so that operator(long) works for both
            column vectors and now also for row vectors.
          - Added a set_size() and constructor that takes a single long for use in
            sizing row and column vectors.
          - Added the scale_columns() function

    Non-Backwards Compatible Changes:

    Bug fixes:
       - Fixed an error in svm_nu_train() where it would incorrectly
         complain of incorrect nu values for some datasets.
       - Added a missing std:: qualifier at two points in the dlib/vector code that
         could cause a compiler error in some instances.

    Other:
       - Added a term index to the documentation.

# Release 15.9

Release date: Sep 25, 2007
Major Changes in this Release:

    New Stuff:
       - Added a nu support vector classifier training function.
       - Added a multilayer neural network object.
       - Added the "destructive aliasing" checks into the matrix code.  Now temporary
         matrices are only created during assignment if the right hand side aliases
         the left hand side in a destructive way.  This removes many of the previous
         uses of temporary matrices.
       - Made the sum() matrix function be able to sum matrices of matrices
       - New matrix functions:
          - acos(), asin(), atan(), ceil(), cos(), cosh(), exp(), floor(), log(),
            log10(), mean(), norm(), pow(), reciprocal(), round_zeros(), sin(),
            sinh(), sqrt(), tan(), tanh(), variance(), and more overloads of
            uniform_matrix().

    Non-Backwards Compatible Changes:

    Bug fixes:
       - Added missing nr() and nc() functions to the uniform_matrix() and
         identity_matrix() functions.
       - Forgot to add a destructor for the dynamically sized matrix resulting in a
         memory leak.  This is now fixed.
       - Fixed various potential compile time errors

    Other:

# Release 15.8

Release date: Sep 11, 2007
Major Changes in this Release:

    New Stuff:
       - Added a copy of the boost noncopyable base class.
       - added some smart pointers:
          - added shared_ptr
          - added weak_ptr
          - added scoped_ptr

    Non-Backwards Compatible Changes:

    Bug fixes:

    Other:
       - Cleaned up the assert code and removed the need for the dlib/error.ccp file
       - Made the matrix take better advantage of the compile time sized
         dimensions when it can.

# Release 15.7

Release date: Aug 26, 2007
Major Changes in this Release:

    New Stuff:
       - Made it so that command line options have a default conversion to bool
         and the bool tells you if they are on the command line or not.
       - Added an implicit conversion to a scalar to the matrix object
         when it is of dimension 1x1.
       - Added the thread_function object
       - Added a function to compute the singular value decomposition of a matrix.

    Non-Backwards Compatible Changes:
       - Added two new arguments to the on_request() function.  They allow you to
         see what HTTP headers the client sends you and to control which ones
         you send back.

    Bug fixes:

    Other:

# Release 15.6

Release date: Aug 18, 2007
Major Changes in this Release:

    New Stuff:
      - matrix object additions:
         - Added some functions to convert between matrix and pixel objects.
         - Added the clamp() function that operates on matrix objects.
         - Added the sigmoid function.
         - Made the matrix object capable of being sized at runtime in addition
           to its original compile time static sizing capability.
         - Added 3 and 4 argument versions of pointwise_multiply()
         - Added the +=, -=, *= and /= operators to the matrix object.

    Non-Backwards Compatible Changes:

    Bug fixes:
      - Fixed the line numbering in the color pretty printer.  Wasn't being
        done correctly.
      - Fixed a bug in the matrix round() function.
      - Fixed some miscellaneous compile time errors
      - Fixed a bug in the matrix removerc() function.
      - Added some missing checks to catch invalid negative index inputs to
        matrix objects.
      - Fixed a bug in the matrix inv() function.  It could sometimes
        segfault if used on certain singular matrices

    Other:
      - string_cast() can now convert hex strings to integers
      - You can now say myarray2d.set_size(0,0) and have it do what
        you would naturally expect.
      - Added some #pragma statements that tell visual studio
        to link the right system libraries automatically.
        So now you don't have to add these things in the
        project settings anymore.

# Release 15.5

Release date: Jul 12, 2007
Major Changes in this Release:

    New Stuff:
      - Added the set_all_logging_levels(), set_all_logging_output_streams()
        functions
      - Added the configure_loggers_from_file() function which allows you to
        easily configure all logger objects using a textual configuration
        file.

    Non-Backwards Compatible Changes:

    Bug fixes:
       - Added a workaround into the code that avoids a potential compilation
         error on Mac OS X systems.

    Other:

# Release 15.4

Release date: Jun 30, 2007
Major Changes in this Release:

    New Stuff:

    Non-Backwards Compatible Changes:

    Bug fixes:
       - Fixed a bug in the POSIX version of the hostname_to_ip() function. It was
         screwy if you asked for more than the first IP address (the same address
         might be returned more than once).
       - Fixed a bug in the pipe object's timeout functions.  The timeouts weren't
         working correctly.

    Other:

# Release 15.3

Release date: Jun 25, 2007
Major Changes in this Release:

    New Stuff:
       - Added the wait_for_num_blocked_dequeues(), enable_enqueue(),
         disable_enqueue(), and is_enqueue_enabled() functions to the pipe object.
       - The pipe object can now be used with a zero length buffer.

    Non-Backwards Compatible Changes:
       - There is no longer a pipe::kernel_1a_c typedef since the pipe
         no longer has any requirements to check (due to the change of allowing
         zero length buffer sizes)

    Bug fixes:

    Other:
       - Made the ASSERT and CASSERT macros call dlib_assert_breakpoint() when they
         fail.  This way you can easily set a breakpoint on them in a debugging
         tool by breaking on calls to this new function.
       - Fixed some typos and unclear parts of the pipe spec.

# Release 15.2

Release date: Jun 11, 2007
Major Changes in this Release:

    New Stuff:
       - Added a thread safe version of the config_reader object (in the form of an
         extension to the config_reader)
       - Added the wait_until_empty() function to the pipe object.

    Non-Backwards Compatible Changes:
       - Removed the connection::close() and listener::close() functions.  They have
         been replaced by destructors.  To upgrade old code all you have to do is
         replace statements of the form "object->close();" with "delete object;".
         Both statements do exactly the same thing.  However, for connection objects,
         you should probably be using the close_gracefully() function instead.

    Bug fixes:
       - Removed a potential compile time error in the dng image format handling code.
       - Fixed a bug in the bigint object.  The destructor was using "delete"
         when it should have been using "delete []"
       - Fixed a resource leak in the POSIX version hostname_to_ip()
       - Fixed a significant memory leak in memory_manager_kernel_1
       - Fixed a memory leak that could occur in memory_manager_kernel_2
         and memory_manager_kernel_3 when the constructor for the object
         being constructed threw an exception.
       - Added a missing delete statement to plug a memory leak
         in the md5 computation code.
       - Fixed an uninitialized variable warning from valgrind
         (in lz77_buffer/lz77_buffer_kernel_2.h).  I think this could
         also potentially result in an error when decoding data but I'm not totally
         sure.  But either way it is fixed now.
       - Changed a call to memcpy to memmove in the sockstreambuf_kernel_2
         implementation since the copy could potentially be of overlapped memory.

    Other:
       - Changed the connection::read() and connection::write() functions to take
         longs instead of unsigned longs as the buffer sizes.  They also now
         return longs instead of ints.  This should be a backwards compatible change.
       - Started using the valgrind tool to check for memory errors in the project and
         found a few things.  Very nice tool :)

# Release 15.1

Release date: Jun 04, 2007
Major Changes in this Release:

    New Stuff:
       - Added the multithreaded_object extension to the threads API
       - Added the load_dng() and save_dng() functions which can load and store
         the DNG lossless compressed image format (which I just made up).

    Non-Backwards Compatible Changes:
       - Changed the serialization format for bool to use a 1 byte code rather than 2
         bytes.  So this breaks compatibility with the old format.

    Bug fixes:
       - The serialization for bool didn't always work right.  This is now fixed.

    Other:

# Release 15.0

Release date: May 16, 2007
Major Changes in this Release:

    New Stuff:
       - New faster version of the bigint object (bigint_kernel_2) that uses
         the Fast Fourier Transform to perform multiplications.
       - The base_window can now be an "undecorated" window.  This new type is suitable
         for making things like popup menus and the like.
       - Added the on_focus_lost() event to the base_window object
       - Added the on_focus_gained() event to the base_window object
       - Added the on_window_moved() event to the base_window object
       - Added the get_pos() function to the base_window object
       - Updated the gui_widgets's drawable interface stuff to support the three
         new event types and the new window type.
       - Added the drawable::draw_rectangle() function
       - Added serialization support for std::complex.
       - Added the assign_image() function

    Non-Backwards Compatible Changes:
       - Removed the color arguments from the drawable_window object's constructor and
         added a new boolean argument (if it is an undecorated window or not).  This
         probably won't break any code but if it does you should get a compiler error
         about it.
       - Made it so you must disable the events in the destructor for your
         drawable gui widgets.  Doing so avoids potential race conditions when
         destructing drawable objects.
       - Made it so that you are required to call close_window() in a window object's
         destructor.  This avoids a potential race condition.

    Bug fixes:
       - Added a workaround for a bug in MinGW that caused the regression test suite
         to crash when compiled with -O3.
       - Fixed a potential bug in the X Windows version of the gui_core component.
          Added an extra XFlush() to end_program() because without it a
          program can crash when calling end_program() in certain instances.
       - The spec for the pipe object said that objects you enqueue into it
         had an "initial value for their type" after the function completes. This
         is incorrect, they are swapped into the pipe so they have an undefined
         value afterwards.  I fixed the spec for the pipe to say this.
       - Fixed a bug in the font rendering functions in the gui_widgets
         component.  It could cause a segmentation fault sometimes.
       - Fixed some potential deadlocks in the windows version of the gui_core
         component.
       - Fixed a bug in the rsignaler object.  When you called wait() or
         wait_or_timeout() it only unlocked the associated rmutex once (it could be
         locked more than once and thus might cause a deadlock since the thread
         calling wait() wouldn't actually unlock the mutex in this case).
       - Fixed the initialize_array() function in memory_manger_kernel_3 to be
         exception safe.  Previously if an exception occurred while creating
         an array then a resource leak was created.

    Other:
       - Changed the package format for the library somewhat.  The examples are now
         located in their own top level folder.  Additionally, the HTML version of the
         documentation also comes in the same archive as the source rather than in a
         separate download.
       - Started using major and minor version numbers rather than just major ones.

# Release 14

Release date: Apr 11, 2007
Major Changes in this Release:

    New Stuff:
       - Added operator<< and operator>> iostream operators to the vector object.

    Non-Backwards Compatible Changes:
       - Changed the xml_parser's document_handler interface:
         made empty element tags (<like_this/>) trigger the end_element() callback
         and removed the is_empty bool from start_element().

    Bug fixes:
       - Fixed a potential race condition between the destruction of the thread pool
         and the "program ending handlers" stuff.

    Other:
       - Made the xml parser more robust to different types of new line characters.
       - Modified the source slightly so that it works with mingw.

# Release 13

Release date: Mar 01, 2007
Major Changes in this Release:

    New Stuff:
       - The config_reader is now enumerable.
       - Added the image_widget gui object.
       - Added nr() and nc() to the array2d object.
       - Added the shutdown_connection() function to the iostream extension
         to the server object.
       - Added the timer_kernel_2 implementation which is a version of the timer object
         that is more efficient in its allocation of threads.
       - Added the timeout object.
       - There is now a CMakeLists.txt file located in the dlib folder.  See
         dlib/examples/CMakeLists.txt and dlib/test/CMakeLists.txt for examples
         that use CMake to build projects using this library.
       - Added the register_program_ending_handler() function to the threading API.

    Non-Backwards Compatible Changes:
       - Removed the config_reader::get_blocks() function.  Use the
         new enumerable interface for the config_reader instead.
       - The array2d object now uses longs instead of unsigned longs to report
         its dimensions and access its elements.
       - Added a uint64 to the on_connect() callback in the iostream
         extension to the server object.
       - timer::set_delay_time() now throws and timer::start() now may throw
         std::bad_alloc.

    Bug fixes:
       - Fixed a bug in end_program().  In X Windows it might not cause the
         program to end right away if it was called from outside the event
         handling thread.
       - Fixed a bug in the implementation of the timeout part of the
         close_gracefully() function.

    Other:
       - The library now works on HP-UX
       - The regression test suite now has command line arguments that
         enable tests to send debug messages to a file.

# Release 12

Release date: Feb 07, 2007
Major Changes in this Release:

    New Stuff:
       - The http server extension now supports the POST HTTP method.
       - The attribute list object in the xml_parser is now enumerable.
       - Added the threaded object extension
       - Added the uintn.h file which defines fixed sized unsigned integral types.

    Non-Backwards Compatible Changes:
       - Renamed the on_get() callback in the http extension to the server object to
         on_request()
       - Removed the network byte order functions from the sockets api.  (They are still
         really there though since they come from actual OS header files.  But
         officially they have been replaced by the byte_orderer component).
       - Renamed dlib/uint64.h to dlib/uintn.h

    Bug fixes:

    Other:
       - The command line parser will now let you declare long named options with -
         characters in them.
       - Made it so you can use the COMPILE_TIME_ASSERT macros anywhere rather than
         just inside functions.

# Release 11

Release date: Dec 27, 2006
Major Changes in this Release:

    New Stuff:
       - For dlib::matrix
          - Added the tmp() function
          - Added optimized specializations of inv() and det() for 1x1, 2x2, 3x3 and
            4x4 matrices.
          - Added the removerc() function
       - Sockets related
          - Added the connect() function
          - Added the is_ip_address() function.
          - Added the close_gracefully() function
          - Added the iostream extension to the server object.
          - Added the http extension to the server object.

    Non-Backwards Compatible Changes:
       - Changed the cpp_tokenizer to not convert characters to their html form.

    Bug fixes:
       - Removed some potential compile time errors.  See the change log for details.

    Other:
       - Improved the web site
       - Added some more example code
       - Added more colors to cpp_pretty_printer_kernel_1.

# Release 10

Release date: Nov 28, 2006
Major Changes in this Release:

    New Stuff:
       - std::map is now serializable
       - Added the matrix object and a bunch of supporting code.
       - Added the list_box graphical widget
       - Added the fill_rect_with_vertical_gradient() function to the
         drawable interfaces list of drawing helpers.
       - Added the open_file_box() function which provides a simple file chooser.

    Non-Backwards Compatible Changes:

    Bug fixes:
       - Made timestamper::get_timestamp() be a const function like it should.  Fixes
         some compile errors.
       - Fixed a bug in the font::draw_string() function.  It didn't redraw
         multi-line strings right.
       - Fixed a bug in the scroll_bar object that would cause a compile
         error if you tried to call its width() function.
       - Fixed a bug in the array_kernel_1 object.  It would cause a segmentation fault
         when used sometimes.

    Other:

# Release 9

Release date: Oct 23, 2006
Major Changes in this Release:

    New Stuff:
       - Added the following image transformation functions:
          - Added the equalize_histogram() function
          - Added the spatially_filter_image() function
          - Added the threshold_image() function
          - Added the binary_dilation() function
          - Added the binary_erosion() function
          - Added the binary_open() function
          - Added the binary_close() function
          - Added the binary_intersection() function
          - Added the binary_difference() function
          - Added the binary_complement() function
       - Added the clear(), load_from() and default constructor back into the
         config_reader.
       - Made the member_function_pointer copyable and also added operator== and !=
         to it.

    Non-Backwards Compatible Changes:
       - Made the vector object templated so you can use types other than double with it.
         But now you
         have to specify what type you want to use which is slightly different.
       - The asc_pair_remover and asc_remover abstract classes now take a third template
         argument.  I highly doubt this effects any code outside the library but it is
         possible.

    Bug fixes:
       - Fixed a bug in the base_window::set_size() function.  If you specified a size
         of (0,0) it caused your program to error out.  This has now been fixed.
       - Fixed a bug in the scroll_bar widget.
       - Fixed a bug in save_bmp().  For some image sizes it would output a goofy
         looking skewed image.

    Other:
       - Switched everything that used to call operator< directly to instead use
         std::less or to take a template argument that provides a compare functor that
         defaults to std::less.

# Release 8

Release date: Oct 03, 2006
Major Changes in this Release:

    New Stuff:
       - Added the assign_pixel() function
       - Added the hsi pixel type
       - Added the save_bmp() function
       - Added the static_switch template

    Non-Backwards Compatible Changes:
       - Changed how the config_reader works.  It now has a more powerful syntax and
         improved interface.  Converting any old code to use the new version should be
         simple since the new file syntax is very nearly backwards compatible with the
         old syntax.  (i.e. You probably won't have to change anything about your
         config files)
       - Renamed the dlib/image_loader.h file to dlib/image_io.h since it now includes
         the image saver stuff.
       - Renamed the pixel struct to rgb_pixel
       - Renamed pixel_traits::color to pixel_traits::rgb
       - Renamed pixel_traits::scalar to pixel_traits::grayscale

    Bug fixes:
       - Fixed a bug in the load_bmp() function.  It would load 24bit bmp files
         incorrectly.
       - Changed the logger so that it won't deadlock if you write something similar to
         my_log << LINFO << function_that_also_logs();.  Although this is a
         dumb thing to do.  But even so, it shouldn't deadlock.
       - Fixed a potential linking problem with the vector object.

    Other:
       - I decided I'm not going to support Borland v5.5.1 anymore.  There are just too
         many bugs in this compiler.  It is very old at this point so I don't see this
         being a big deal.
       - Made the drawable::draw_image() and load_bmp() functions able to handle images
         of any type of pixel.
       - Pulled the imaging, algorithmic and metaprogramming stuff out of the
         miscellaneous section of the web page and gave them all their own sections.

# Release 7

Release date: Sep 18, 2006
Major Changes in this Release:

    New Stuff:
       - Added a logger header that prints the date and time.
       - Added the LTRACE logging level
       - Added a buffered implementation of sockstreambuf.

    Non-Backwards Compatible Changes:
       - Changed the specs to say that sockstreambuf may be buffered.
         sockstreambuf_kernel_1 is still just as it always has been though.  So all old
         code will still work just as it always has.  But all the same, the specs have
         been changed and now allow for an implementation that is not 100% backwards
         compatible.
       - rand_kernel_2 now emits a different string of random numbers.

    Bug fixes:
       - Changed the logger object's implementation to not try to register
         a thread end handler for the main program thread anymore.  This was
         technically a bug according to the spec but it actually did end up
         working the way it was supposed to.  But even so, it shouldn't have
         been doing that.
       - Changed binary_search_tree_kernel_1 so that it avoids a bug in the version of
         gcc on SuSE Enterprise Linux 9.
       - Fixed a bug in the rand_kernel_2 implementation.  It wasn't giving good
         random numbers.

    Other:
       - Modified the code so that you don't get any warnings when -Wall is used with
         GCC.

# Release 6

Release date: Aug 30, 2006
Major Changes in this Release:

    New Stuff:
       - Added the ASSERT_ARE_SAME_TYPE macro
       - Added the is_same_type template
       - Added the get_main_thread_id() function to the threading API
       - Added the thread_specific_data extension to the threading API
       - Added the logger object.
       - Added the auto_unlock object to the threading API.

    Non-Backwards Compatible Changes:

    Bug fixes:

    Other:
       - Added an example that is specifically about using threads
       - Added two examples about using the logger object

# Release 5

Release date: Aug 18, 2006
Major Changes in this Release:

    New Stuff:
       - Added the memory_manager_stateless object and two implementations of it.
       - Added the MACOSX macro to dlib/platform.h
       - Added a templated version of create_new_thread() that allow you to start
         a thread with a member function.
       - Added the register_thread_end_handler() function to the threading kernel API.
       - Added memory_manager_kernel_3

    Non-Backwards Compatible Changes:
       - Changed the meaning of the memory_manager_global::get_number_of_allocations()
         function because the previous definition of it didn't really make sense for
         this object.
       - Changed the threading API to wait for all outstanding threads to terminate
         before allowing the program to end.  It used to just let the OS trash those
         threads when main() ended but this isn't a safe or portable thing to do.  I
         used to assume the user would make sure all their threads were done and had
         cleaned up whatever they were doing before main() ended but this is too much
         of a burden on the end user.  So now the library will wait for your threads to
         end.  You still need to have some way of telling them it is time to stop though.

    Bug fixes:
       - Fixed a minor bug in dlib/timer/timer_kernel_1.h.  Its implementation was
         slightly off according to the specification of a timer object.

    Other:
       - The byte_order object is now capable of flipping entire arrays.
       - Made it so that the ENABLE_ASSERTS macro is defined whenever ASSERT is
         on.
       - Made the array container use the memory managers.

# Release 4

Release date: Jul 18, 2006
Major Changes in this Release:

    New Stuff:
       - Added functions to explicitly convert to/from little and big endian to the
         byte_order object.
       - Added the allocate_array() and deallocate_array() functions to the
         memory_manager.
       - Created the memory_manager_global object
       - Added the remove_last_in_order(), position_enumerator() and
         remove_current_element() functions to the binary_search_tree object.

    Non-Backwards Compatible Changes:
       - I put an #error directive in the old GUI component to notify anyone
         trying to use it that it is deprecated.  I will be removing it from the
         library in a few months.
       - Switched the reference_counter object back to not using the memory_manager.
         I realized it isn't safe for this object to use the memory_manager since
         it could result in memory_managers freeing each other's allocations.
       - I redefined the pixel_traits template.  It is now a lot simpler and more
         convenient.

    Bug fixes:
       - Fixed a minor bug in dlib/rand/rand_kernel_2.cpp

    Other:
       - Added some more compile time checks to the byte_orderer object.
       - Changed some includes and preprocessor macros around a little so now
         everything but the GUI stuff compiles in mac OS X.
       - Added inclusion guards to all the .cpp files
       - Added the all_gui.cpp and all_console.cpp files.  They
         include all the .cpp files you need to make gui and
         console applications respectively into one file.
       - Made more containers use the memory_manager.

# Release 3

Release date: May 06, 2006
Major Changes in this Release:

    New Stuff:
       - Added the enqueue_or_timeout() and dequeue_or_timeout() functions
         to the pipe object.
       - Gave the mouse_tracker the ability to display the mouse position
         relative to a user selected point.
       - Added the message_box() function to the gui_widgets component.
       - Gave the label widget the ability to draw newlines in strings.
       - added the close_window() and is_closed() methods to the base_window
         object.
       - Added the rsignaler extension to the threading API.
       - You can now control the thread pool timeout time by setting the
         DLIB_THREAD_POOL_TIMEOUT #define.
       - Added the get_from_clipboard() and put_on_clipboard() functions
         to the gui_core component.
       - Added the stop_and_wait() function to the timer object.
       - Added the trigger_user_event() function and on_user_event() event
         to the base_window object.  This new event is also forwarded
         to drawable interfaces inside the receiving window.
       - Added the wrap_around() function to the named_rectangle widget.
       - Added the top(), left(), right(), bottom(), width() and height()
         functions to the drawable interface.

    Non-Backwards Compatible Changes:
       - Made the radio_button and check_box widgets pass references to themselves
         when they call their click handlers.
       - Switched the sync_extension to use the rmutex and rsignaler objects
         rather than the normal non-reentrant ones. ( Chances are that old
         code that used this will still compile fine anyway. )
       - Changed the return type of rand::get_random_number() to be an
         unsigned char.  I also changed both the implementations of
         rand because they weren't very good at all.
       - Changed the functions related to drawing strings in the font class.
       - Changed the drawable's rectangle to default to being empty
         rather than being a single point.  Most code should not notice
         the difference.

    Bug fixes:
       - The event handlers in gui_widgets/drawable.h were private.  They
         should be protected.  This is now fixed.
       - Fixed a bug in the way the scroll_bar was drawn when it was
         the HORIZONTAL type.
       - Changed how the thread pool destructs itself when the program
         is ending.  Previously it was possible to get an error on
         NetBSD when the program was ending.  This is now fixed.
       - The functions related to setting the jump size in the scroll_bar
         widget were private.  They are now public.
       - There was a bug in the MS Windows version of the gui_core component
         where the members of the base_window would not work if called from
         within the on_window_close() event.  This has now been fixed.
       - Made the set_pos() function work right for the mouse_tracker widget.
       - Fixed a bug in the base64 object where the string "" could potentially
         be decoded incorrectly.
       - Made the global swap function for crc32_kernel_1 inline.  This fixes a
         potential linker error.
       - Fixed some potential deadlocking that could occur while using the
         gui widgets.

    Other:
       - I moved all the regression tests into the dlib/test folder and
         made a nice driver program to run all of them.
       - I have been using the sourceforge compile farms to test the library
         on various platforms.  It now works for Solaris and some of the BSDs
         in addition to Linux and Windows.

# Release 2

Release date: Apr 08, 2006
Major Changes in this Release:

    New Stuff:
       - Added the array_expand extension to the array object.
       - Added the cmd_line_parser_check extension to the command line parser.
       - Added the pipe object.
       - All applicable container classes now use the memory_manager component for
         their memory allocation.
       - New implementations of the memory_manager object.
       - Added the copy_functor class.

    Non-Backwards Compatible Changes:
       - Moved the wrap_string, narrow, and string_cast functions
         to a new file.  You now have to include dlib/string.h to get
         them.  (This makes a bunch of other things work right in gcc 2.95)
       - Renamed the _L macro to _dT
       - Removed the scopy class
       - Simplified the interface to the memory manager.  It is basically the same
         though.
       - Removed the max_size() methods from the hash_table and binary_search_tree
         objects.
       - Removed the T_is_POD template arguments from the hash_table and
         binary_search_tree objects.
       - Simplified the template arguments to all checking components and extensions.
         They now take the class they are to extend or check as their only template
         argument.  This only affects you if you haven't been using the kernel_nx
         typedefs.

    Bug fixes:

    Other:
       - I changed a few things around and now a majority of the library
         again compiles under gcc 2.95.  But some things don't and I currently
         don't plan on making them work because it involves hackish workarounds
         of 2.95's bugs.
       - Changed the compress_stream_kernel_1 object so that it will detect data
         corruptions better.  This change will prevent it from correctly decompressing
         data that was compressed with a previous version and has an uncompressed size
         greater than about 20,000 bytes.
       - There is a new cpp file you need to compile:  dlib/error.cpp
       - Moved all the regression testing stuff into the dlib/test folder and made
         a nicer test driver to run them.

# Release 1

Release date: Mar 19, 2006
Major Changes in this Release:

    New Stuff:
        - Created the byte_orderer object.
        - Created the mouse_tracker gui widget.
        - The sliding_buffer object is now enumerable and serializable.
        - Added the get_filesystem_roots() function to the dir_nar component.
        - Added the create_directory() function to the misc_api component.

    Non-Backwards Compatible Changes:
        - The ASSERT macro is now only enabled if DEBUG or ENABLE_ASSERTS
          is defined.

    Bug fixes:
        - Fixed a minor bug in the cmd_line_parser object.  If you gave
          an option such as --option=arg when option didn't take any
          arguments it could hang your program.
        - Fixed a bug in wait_or_timeout() in the posix version of the threading
          api.  The time to wait for was being calculated incorrectly and could
          result in an excessive number of spurious returns.
        - Fixed a minor bug in the on_keydown() event for windows.
          I had it set such that the shift and ctrl bools would be false
          if they were the actual keys being pressed.  This isn't what the
          specs say should happen but I had a comment in the windows code
          that made it clear that I did it on purpose.  Go figure :)
          This is now fixed.

    Other:
        - Improved the cpp_tokenizer object's ability to recognize numerical
          constants.
        - Improved the text_field gui widget.
        - There are now two assert macros.  One called ASSERT
          and another CASSERT.  They both do the same thing but ASSERT
          is only enabled when DEBUG or ENABLE_ASSERTS is defined.
          All the old ASSERT statements were changed to CASSERT statements.

# Release 2006-02-23.01

Major Changes in this Release:

    New Stuff:
        - Added array_kernel_2 which is a simple layer on top of a C array.
        - Added the tabbed_display GUI widget
        - Added the widget_group GUI widget
        - Added the named_rectangle GUI widget
        - Added the pixel_traits template

    Non-Backwards Compatible Changes:
        - The default maximum size for an array object is now 0 rather than
          20,000.
    Bug fixes:

    Other:
        - made the cpp_pretty_printer a little better about how it handles
          C style code.  Also added support for /*!A html_anchor_name !*/
          style comments.

# Release 2006-01-31.02

Major Changes in this Release:

    New Stuff:
        - Created the array2d object.
        - Created the base64 object.
        - Created the pixel struct.
        - Created the load_bmp() function which can load a BMP image file
          into an array2d object of pixels.
        - Created the drawable::draw_image() function

    Non-Backwards Compatible Changes:
        - In the drawable interface I made the z order a long rather
          than unsigned long.
        - The cpp_tokenizer object now has a NUMBER token type.
        - removed the get_ prefix from functions in the cmd_line_parser
          and cmd_line_parser_option objects.  Also changed the
          cmd_line_parser_option::operator[] function to a normal member
          function called argument().

    Bug fixes:

    Other:
        - cpp_pretty_printer now colors numeric literals a shade of yellow.

# Release 2006-01-15.03

Major Changes in this Release:

    New Stuff:
        - Created the member_function_pointer object.
        - Created the button_action object.
        - Created the arrow_button object.
        - Created the check_box object.
        - Created the radio_button object.
        - Created the scroll_bar object.
        - More drawing functions to draw various things
          onto a canvas object.
        - Added enable/disable functions to the
          drawable interface.

    Non-Backwards Compatible Changes:
        - The gui widgets are no longer templated at the
          class level.
        - The drawable object's constructor now takes a
          bit set rather than a bunch of bools to tell it
          which events to enable.
        - I changed the names of some of the functions in the
          gui_widgets component so that they all reflected a
          uniform naming style.

    Bug fixes:
        - Fixed a minor bug in the cpp_tokenizer.
        - Minor bug in the timer object. See change log for
          details.

    Other:
        - Made the timer object a little more robust