Commit eeec129c authored by Tim-Philipp Müller's avatar Tim-Philipp Müller 🐠

New API: gst_type_find_helper_get_range() (#333042).

Original commit message from CVS:
* docs/libs/gstreamer-libs-sections.txt:
* libs/gst/base/gsttypefindhelper.c: (helper_find_peek),
(helper_find_suggest), (gst_type_find_helper_get_range),
(gst_type_find_helper):
* libs/gst/base/gsttypefindhelper.h:
New API: gst_type_find_helper_get_range() (#333042).
parent 96188677
2006-03-02 Tim-Philipp Müller <tim at centricular dot net>
* docs/libs/gstreamer-libs-sections.txt:
* libs/gst/base/gsttypefindhelper.c: (helper_find_peek),
(helper_find_suggest), (gst_type_find_helper_get_range),
(gst_type_find_helper):
* libs/gst/base/gsttypefindhelper.h:
New API: gst_type_find_helper_get_range() (#333042).
2006-03-02 Michael Smith <msmith@fluendo.com>
* gst/gstregistryxml.c: (load_feature):
......
......@@ -260,6 +260,8 @@ gst_push_src_get_type
<INCLUDE>gst/base/gsttypefindhelper.h</INCLUDE>
gst_type_find_helper
gst_type_find_helper_for_buffer
GstTypeFindHelperGetRangeFunction
gst_type_find_helper_get_range
<SUBSECTION Private>
</SECTION>
......
......@@ -56,12 +56,14 @@ type_find_factory_rank_cmp (gconstpointer fac1, gconstpointer fac2)
typedef struct
{
GstPad *src;
guint best_probability;
GstCaps *caps;
guint64 size;
GSList *buffers;
GstTypeFindFactory *factory;
GstTypeFindHelperGetRangeFunction func;
GstObject *obj;
}
GstTypeFindHelper;
......@@ -70,14 +72,12 @@ helper_find_peek (gpointer data, gint64 offset, guint size)
{
GstTypeFindHelper *find;
GstBuffer *buffer;
GstPad *src;
GstFlowReturn ret;
find = (GstTypeFindHelper *) data;
src = find->src;
GST_LOG_OBJECT (src, "'%s' called peek (%" G_GINT64_FORMAT ", %u)",
GST_PLUGIN_FEATURE_NAME (find->factory), offset, size);
GST_LOG_OBJECT (find->obj, "'%s' called peek (%" G_GINT64_FORMAT
", %u)", GST_PLUGIN_FEATURE_NAME (find->factory), offset, size);
if (size == 0)
return NULL;
......@@ -104,7 +104,7 @@ helper_find_peek (gpointer data, gint64 offset, guint size)
}
buffer = NULL;
ret = GST_PAD_GETRANGEFUNC (src) (src, offset, size, &buffer);
ret = find->func (find->obj, offset, size, &buffer);
if (ret != GST_FLOW_OK)
goto error;
......@@ -134,7 +134,7 @@ helper_find_suggest (gpointer data, guint probability, const GstCaps * caps)
{
GstTypeFindHelper *find = (GstTypeFindHelper *) data;
GST_LOG_OBJECT (find->src,
GST_LOG_OBJECT (find->obj,
"'%s' called called suggest (%u, %" GST_PTR_FORMAT ")",
GST_PLUGIN_FEATURE_NAME (find->factory), probability, caps);
......@@ -148,18 +148,30 @@ helper_find_suggest (gpointer data, guint probability, const GstCaps * caps)
}
/**
* gst_type_find_helper:
* @src: A source #GstPad
* gst_type_find_helper_get_range:
* @obj: A #GstObject that will be passed as first argument to @func
* @func: A generic #GstTypeFindHelperGetRangeFunction that will be used
* to access data at random offsets when doing the typefinding
* @size: The length in bytes
* @prob: location to store the probability of the found caps, or #NULL
*
* Tries to find what type of data is flowing from the given source #GstPad.
* Utility function to do pull-based typefinding. Unlike gst_type_find_helper()
* however, this function will use the specified function @func to obtain the
* data needed by the typefind functions, rather than operating on a given
* source pad. This is useful mostly for elements like tag demuxers which
* strip off data at the beginning and/or end of a file and want to typefind
* the stripped data stream before adding their own source pad (the specified
* callback can then call the upstream peer pad with offsets adjusted for the
* tag size, for example).
*
* Returns: The #GstCaps corresponding to the data stream.
* Returns #NULL if no #GstCaps matches the data stream.
*/
GstCaps *
gst_type_find_helper (GstPad * src, guint64 size)
gst_type_find_helper_get_range (GstObject * obj,
GstTypeFindHelperGetRangeFunction func, guint64 size,
GstTypeFindProbability * prob)
{
GstTypeFind gst_find;
GstTypeFindHelper find;
......@@ -167,18 +179,19 @@ gst_type_find_helper (GstPad * src, guint64 size)
GList *walk, *type_list = NULL;
GstCaps *result = NULL;
g_return_val_if_fail (src != NULL, NULL);
g_return_val_if_fail (GST_PAD_GETRANGEFUNC (src) != NULL, NULL);
g_return_val_if_fail (GST_IS_OBJECT (obj), NULL);
g_return_val_if_fail (func != NULL, NULL);
type_list = gst_type_find_factory_get_list ();
type_list = g_list_sort (type_list, type_find_factory_rank_cmp);
find.src = src;
find.best_probability = 0;
find.caps = NULL;
find.size = size;
find.buffers = NULL;
find.func = func;
find.obj = obj;
gst_find.data = &find;
gst_find.peek = helper_find_peek;
gst_find.suggest = helper_find_suggest;
......@@ -205,9 +218,39 @@ gst_type_find_helper (GstPad * src, guint64 size)
gst_buffer_unref (GST_BUFFER_CAST (l->data));
g_slist_free (find.buffers);
if (prob)
*prob = find.best_probability;
GST_LOG_OBJECT (obj, "Returning %" GST_PTR_FORMAT " (probability = %u)",
result, (guint) find.best_probability);
return result;
}
/**
* gst_type_find_helper:
* @src: A source #GstPad
* @size: The length in bytes
*
* Tries to find what type of data is flowing from the given source #GstPad.
*
* Returns: The #GstCaps corresponding to the data stream.
* Returns #NULL if no #GstCaps matches the data stream.
*/
GstCaps *
gst_type_find_helper (GstPad * src, guint64 size)
{
GstTypeFindHelperGetRangeFunction func;
g_return_val_if_fail (GST_IS_OBJECT (src), NULL);
g_return_val_if_fail (GST_PAD_GETRANGEFUNC (src) != NULL, NULL);
func = (GstTypeFindHelperGetRangeFunction) (GST_PAD_GETRANGEFUNC (src));
return gst_type_find_helper_get_range (GST_OBJECT (src), func, size, NULL);
}
/* ********************** typefinding for buffers ************************* */
typedef struct
......
......@@ -34,6 +34,33 @@ GstCaps * gst_type_find_helper_for_buffer (GstObject *obj,
GstBuffer *buf,
GstTypeFindProbability *prob);
/**
* GstTypeFindHelperGetRangeFunction:
* @obj: a #GstObject that will handle the getrange request
* @offset: the offset of the range
* @length: the length of the range
* @buffer: a memory location to hold the result buffer
*
* This function will be called by gst_type_find_helper_get_range() when
* typefinding functions request to peek at the data of a stream at certain
* offsets. If this function returns GST_FLOW_OK, the result buffer will be
* stored in @buffer. The contents of @buffer is invalid for any other
* return value.
*
* This function is supposed to behave exactly like a #GstPadGetRangeFunction.
*
* Returns: GST_FLOW_OK for success
*/
typedef GstFlowReturn (*GstTypeFindHelperGetRangeFunction) (GstObject *obj,
guint64 offset,
guint length,
GstBuffer **buffer);
GstCaps * gst_type_find_helper_get_range (GstObject * obj,
GstTypeFindHelperGetRangeFunction func,
guint64 size,
GstTypeFindProbability *prob);
G_END_DECLS
#endif /* __GST_TYPEFINDHELPER_H__ */
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