gstreamer/docs/random/porting-to-0.11.txt

The 0.11 porting guide
----------------------

* All deprecated methods were removed. Recompile against 0.10 with
  DISABLE_DEPRECATED and fix issues before attempting to port to 0.11.

* GST_BOILERPLATE is gone, use G_DEFINE_TYPE instead.

* various methods take a gsize instead of a guint when talking about memory
  sizes.

* multifdsink, tcpclientsink, tcpclientsrc, tcpserversrc the protocol property
  is removed, use gdppay and gdpdepay.

* Presets and plugins moved to $XDG_DATA_HOME/gstreamer-0.11/ root
  directory. Registry moved to $XDG_CACHE_HOME/gstreamer-0.11/.
  XDG_CACHE_HOME usually points to $HOME/.cache and XDG_DATA_HOME
  usually is $HOME/.local/share/.

* GstObject:
    GST_OBJECT_DISPOSING flag removed
    GST_OBJECT_IS_DISPOSING removed
    GST_OBJECT_FLOATING flag remove, GstObject is now GInitiallyUnowned
    GST_OBJECT_IS_FLOATING removed, use g_object_is_floating()

    GST_CLASS_GET_LOCK, GST_CLASS_LOCK, GST_CLASS_TRYLOCK, GST_CLASS_UNLOCK,
    used to be a workaround for thread-unsafe glib < 2.8

    gst_object_ref_sink() has gpointer as result to make it more like the
    GObject version.

    gst_object_sink() removed, use gst_object_ref_sink() instead.

    gst_class_signal_connect() removed, was only used for XML

    parent-set and parent-unset signals removed. Use notify:parent. Currently
    still disabled because of deep notify locking issues.

* GstElement:
    GstElementDetails is removed and replaced with more generic metadata.

    gst_element_class_set_details_simple() -> gst_element_class_set_metadata()
    gst_element_class_set_documentation_uri -> gst_element_class_add_metadata
    gst_element_class_set_icon_name -> gst_element_class_add_metadata

    gst_element_factory_get_longname -> gst_element_factory_get_metadata
    gst_element_factory_get_klass -> gst_element_factory_get_metadata
    gst_element_factory_get_description -> gst_element_factory_get_metadata
    gst_element_factory_get_author -> gst_element_factory_get_metadata
    gst_element_factory_get_documentation_uri -> gst_element_factory_get_metadata
    gst_element_factory_get_icon_name -> gst_element_factory_get_metadata

    gstelementmetadata.h contains the keys for all standard metadata.

    Element metadata and pad templates are inherited from parent classes and
    should be added in class_init instead of base_init.

    gst_element_class_add_pad_template() takes ownership of the template

    Elements that change the duration must post DURATION messages on the
    bus when the duration changes in PAUSED or PLAYING.

* GstPad:
    gst_pad_get_caps() does not return writable caps anymore and an explicit
    gst_caps_make_writable() needs to be performed. This was the functionality
    of gst_pad_get_caps_reffed(), which is removed now.

    A similar change was done for gst_pad_peer_get_caps() and
    gst_pad_peer_get_caps_reffed()

    gst_pad_set_bufferalloc_function(), gst_pad_alloc_buffer() and
    gst_pad_alloc_buffer_and_set_caps() are removed. Use the ALLOCATION query
    now to obtain a reference to a bufferpool object that can be used to
    allocate buffers.

* GstMiniObject
    A miniobject is now a simple refcounted structure holding the information
    common to buffers, events, messages, queries and caps.

    There is no more GST_TYPE_MINIOBJECT as the type for subclasses.
    G_TYPE_BOXED can be used as the type of all GstMiniObject based types such
    as buffers, events, messages, caps, etc. Signals, for example, would use the
    boxed type if the argument include GstMiniObject derived types.

    gst_mini_object_new() is removed. You would allocate memory with the the
    methods specific for the derived type.

    GstParamSpecMiniObject is removed, use boxed param spec now with the GType
    of the specific GstMiniObject derived type. Also
    gst_param_spec_mini_object().

    gst_param_spec_mini_object() -> g_param_spec_boxed()

    The specific gst_value_*_mini_object() methods are removed, used the generic
    boxed methods instead.

    gst_value_set_mini_object() -> g_value_set_boxed()
    gst_value_take_mini_object() -> g_value_take_boxed()
    gst_value_take_get_object() -> g_value_get_boxed()
    gst_value_take_dup_object() -> g_value_dup_boxed()

    The GST_MINI_OBJECT_READONLY flag was removed as it used to mark the
    memory in buffers as READONLY. Marking memory READONLY can now be done
    with the GstMemory API. Writability of miniobjects is now only done by using
    the refcount.

* GstBuffer
    A GstBuffer is now a simple boxed type this means that subclassing is not
    possible anymore. 

    To add data to the buffer you would now use gst_buffer_take_memory() with
    a GstMemory object containing the data. Multiple memory blocks can added to
    a GstBuffer that can then be retrieved with gst_buffer_peek_memory().

    GST_BUFFER_DATA(), GST_BUFFER_MALLOCDATA(), GST_BUFFER_FREE_FUNC() and
    GST_BUFFER_SIZE() are gone, along with the fields in GstBuffer. Use the
    memory API to get access to the buffer data. GST_BUFFER_SIZE() can be
    replaced with gst_buffer_get_size() but if also access to the data is
    required, gst_buffer_map() can return both the size and data in one go.

    The most common way to access all the data in a buffer is by using
    gst_buffer_map() and gst_buffer_unmap(). These calls require you to specify
    the access mode required to the data and will automatically merge and return
    a writable copy of the data.

    The buffer must be writable (gst_buffer_is_writable()) in order to modify
    the fields, metadata or buffer memory. gst_buffer_make_writable() will not
    automatically make a writable copy of the memory but will instead increase
    the refcount of the memory. The _map() and _peek_memory() methods will
    automatically create writable copies when needed.
    
    gst_buffer_make_metadata_writable() is gone, you can replace this safely
    with gst_buffer_make_writable().

    gst_buffer_create_sub() is gone and can be safely replaced with
    gst_buffer_copy_region(). 

    Changing the size of the buffer data can be done with gst_buffer_resize(),
    which will also update the metadata fields correctly. gst_buffer_set_size()
    is #defined to a special case of gst_buffer_resize() with a 0 offset.

    gst_buffer_try_new_and_alloc() is replaced with gst_buffer_new_and_alloc(),
    which now returns NULL when memory allocation fails.

* GstBufferList
    The GstBufferList object is much simplified because most of the
    functionality in the groups is now part of the GstMemory in buffers.
    
    The object is reduced to encapsulating an array of buffers that you can send
    with the regular gst_pad_push_list. The iterator is not needed anymore
    because you can simply use gst_buffer_list_len() and gst_buffer_list_get()
    to iterate the array.

    For dealing with the groups, it's now needed to add the memory blocks to
    GstBuffer and use the normal buffer API to get and merge the groups.

* GstEvent
    GST_EVENT_SRC is removed. Don't use this anymore.

* GstQuery
    Boxed types derived from GstMiniObject.

* GstBufferList
    Is now a boxed type derived from GstMiniObject.

* GstMessage
    Is now a boxed type derived from GstMiniObject

* GstCaps
    Is now a boxed type derived from GstMiniObject. 

* GstTypeFind
    gst_type_find_peek() returns a const guin8 * now.

* GstAdapter
    gst_adapter_peek() is removed, use gst_adapter_map() and gst_adapter_unmap()
    to get access to raw data from the adapter.

    Arguments renamed from guint to gsize.

* GstBitReader, GstByteReader, GstByteWriter
    gst_*_reader_new_from_buffer(), gst_*_reader_init_from_buffer() removed, get
    access to the buffer data with _map() and then use the _new() functions.

    gst_byte_reader_new_from_buffer() and gst_byte_reader_init_from_buffer()
    removed, get access to the buffer data and then use the _new() functions.

* GstCollectPads
    gst_collect_pads_read() removed, use _read_buffer() or _take_buffer() and
    then use the memory API to get to the memory.