baseparse: Create baseparse library

1 files changed, 358 insertions, 0 deletions

diff --git a/gst-libs/gst/baseparse/gstbaseparse.h b/gst-libs/gst/baseparse/gstbaseparse.h
new file mode 100644
index 000000000..82ec5f6fb
--- /dev/null
+++ b/gst-libs/gst/baseparse/gstbaseparse.h
@@ -0,0 +1,358 @@
+/* GStreamer
+ * Copyright (C) 2008 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Stefan Kost <stefan.kost@nokia.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef __GST_BASE_PARSE_H__
+#define __GST_BASE_PARSE_H__
+
+#include <gst/gst.h>
+#include <gst/base/gstadapter.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_BASE_PARSE		   (gst_base_parse_get_type())
+#define GST_BASE_PARSE(obj)		   (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BASE_PARSE,GstBaseParse))
+#define GST_BASE_PARSE_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_BASE_PARSE,GstBaseParseClass))
+#define GST_BASE_PARSE_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS((obj),GST_TYPE_BASE_PARSE,GstBaseParseClass))
+#define GST_IS_BASE_PARSE(obj)	   (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BASE_PARSE))
+#define GST_IS_BASE_PARSE_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_BASE_PARSE))
+#define GST_BASE_PARSE_CAST(obj)	((GstBaseParse *)(obj))
+
+/**
+ * GST_BASE_PARSE_SINK_NAME:
+ *
+ * the name of the templates for the sink pad
+ */
+#define GST_BASE_PARSE_SINK_NAME	"sink"
+/**
+ * GST_BASE_PARSE_SRC_NAME:
+ *
+ * the name of the templates for the source pad
+ */
+#define GST_BASE_PARSE_SRC_NAME	        "src"
+
+/**
+ * GST_BASE_PARSE_SRC_PAD:
+ * @obj: base parse instance
+ *
+ * Gives the pointer to the source #GstPad object of the element.
+ *
+ * Since: 0.10.x
+ */
+#define GST_BASE_PARSE_SRC_PAD(obj)	(GST_BASE_PARSE_CAST (obj)->srcpad)
+
+/**
+ * GST_BASE_PARSE_SINK_PAD:
+ * @obj: base parse instance
+ *
+ * Gives the pointer to the sink #GstPad object of the element.
+ *
+ * Since: 0.10.x
+ */
+#define GST_BASE_PARSE_SINK_PAD(obj)	(GST_BASE_PARSE_CAST (obj)->sinkpad)
+
+/**
+ * GST_BASE_PARSE_SEGMENT:
+ * @obj: base parse instance
+ *
+ * Gives the segment of the element.
+ *
+ * Since: 0.10.x
+ */
+#define GST_BASE_PARSE_SEGMENT(obj)     (GST_BASE_PARSE_CAST (obj)->segment)
+
+/**
+ * GST_BASE_PARSE_FLOW_DROPPED:
+ *
+ * A #GstFlowReturn that can be returned from parse_frame to
+ * indicate that no output buffer was generated, or from pre_push_buffer to
+ * to forego pushing buffer.
+ *
+ * Since: 0.10.x
+ */
+#define GST_BASE_PARSE_FLOW_DROPPED     GST_FLOW_CUSTOM_SUCCESS
+
+/**
+ * GstBaseParseFrameFlags:
+ * @GST_BASE_PARSE_FRAME_FLAG_NONE: no flag
+ * @GST_BASE_PARSE_FRAME_FLAG_SYNC: indicates if parsing is 'in sync'
+ * @GST_BASE_PARSE_FRAME_FLAG_DRAIN: indicates if parser is 'draining'.
+ *   That is, leftover data (e.g. in FLUSH or EOS situation) is being parsed.
+ * @GST_BASE_PARSE_FRAME_FLAG_NO_FRAME: set to indicate this buffer should not be
+ *   counted as frame, e.g. if this frame is dependent on a previous one.
+ *   As it is not counted as a frame, bitrate increases but frame to time
+ *   conversions are maintained.
+ * @GST_BASE_PARSE_FRAME_FLAG_CLIP: @pre_push_buffer can set this to indicate
+ *    that regular segment clipping can still be performed (as opposed to
+ *    any custom one having been done).
+ *
+ * Flags to be used in a #GstBaseParseFrame.
+ *
+ * Since: 0.10.x
+ */
+typedef enum {
+  GST_BASE_PARSE_FRAME_FLAG_NONE         = 0,
+  GST_BASE_PARSE_FRAME_FLAG_SYNC         = (1 << 0),
+  GST_BASE_PARSE_FRAME_FLAG_DRAIN        = (1 << 1),
+  GST_BASE_PARSE_FRAME_FLAG_NO_FRAME     = (1 << 2),
+  GST_BASE_PARSE_FRAME_FLAG_CLIP         = (1 << 3)
+} GstBaseParseFrameFlags;
+
+/**
+ * GstBaseParseFrame:
+ * @buffer: data to check for valid frame or parsed frame.
+ *   Subclass is allowed to replace this buffer.
+ * @overhead: subclass can set this to indicates the metadata overhead
+ *   for the given frame, which is then used to enable more accurate bitrate
+ *   computations. If this is -1, it is assumed that this frame should be
+ *   skipped in bitrate calculation.
+ * @flags: a combination of input and output #GstBaseParseFrameFlags that
+ *  convey additional context to subclass or allow subclass to tune
+ *  subsequent #GstBaseParse actions.
+ *
+ * Frame (context) data passed to each frame parsing virtual methods.  In
+ * addition to providing the data to be checked for a valid frame or an already
+ * identified frame, it conveys additional metadata or control information
+ * from and to the subclass w.r.t. the particular frame in question (rather
+ * than global parameters).  Some of these may apply to each parsing stage, others
+ * only to some a particular one.  These parameters are effectively zeroed at start
+ * of each frame's processing, i.e. parsing virtual method invocation sequence.
+ *
+ * Since: 0.10.x
+ */
+typedef struct {
+  GstBuffer       *buffer;
+  guint           flags;
+  gint            overhead;
+} GstBaseParseFrame;
+
+/**
+ * GST_BASE_PARSE_FRAME_SYNC:
+ * @frame: base parse frame instance
+ *
+ * Obtains current sync status indicated in frame.
+ *
+ * Since: 0.10.x
+ */
+#define GST_BASE_PARSE_FRAME_SYNC(frame)     (!!(frame->flags & GST_BASE_PARSE_FRAME_FLAG_SYNC))
+
+/**
+ * GST_BASE_PARSE_FRAME_DRAIN:
+ * @frame: base parse frame instance
+ *
+ * Obtains current drain status indicated in frame.
+ *
+ * Since: 0.10.x
+ */
+#define GST_BASE_PARSE_FRAME_DRAIN(frame)    (!!(frame->flags & GST_BASE_PARSE_FRAME_FLAG_DRAIN))
+
+/**
+ * GstBaseParseFormat:
+ * @GST_BASE_PARSE_FORMAT_NONE: default setting
+ * @GST_BASE_PARSE_FORMAT_PASSTHROUGH: nature of format or configuration
+ *   does not allow (much) parsing, so parser should operate in passthrough mode
+ *   (which only applies operating in pull mode).  That is, incoming buffers
+ *   are pushed through unmodified, i.e. no @check_valid_frame or @parse_frame
+ *   callbacks will be invoked.  On the other hand, @pre_push_buffer is still invoked,
+ *   where subclass can perform as much or as little is appropriate for
+ *   "passthrough" semantics.
+ * @GST_BASE_PARSE_FORMAT_HAS_TIME: frames carry timing info which subclass
+ *   can (generally) parse and provide.  In particular, intrinsic time
+ *   (rather than estimated) can be obtained following seek.
+ *
+ * Since: 0.10.x
+ */
+typedef enum _GstBaseParseFormat {
+  GST_BASE_PARSE_FORMAT_NONE               = 0,
+  GST_BASE_PARSE_FORMAT_PASSTHROUGH        = (1 << 0),
+  GST_BASE_PARSE_FORMAT_HAS_TIME           = (1 << 1),
+} GstBaseParseFormat;
+
+/**
+ * GstBaseParseSeekable:
+ * @GST_BASE_PARSE_SEEK_NONE: No seeking possible.
+ * @GST_BASE_PARSE_SEEK_DEFAULT: Default seeking possible using estimated bitrate.
+ * @GST_BASE_PARSE_SEEK_TABLE: Additional metadata provides more accurate seeking.
+ *
+ * Indicates what level (of quality) of seeking is possible.
+ *
+ * Since: 0.10.x
+ */
+typedef enum _GstBaseParseSeekable {
+  GST_BASE_PARSE_SEEK_NONE,
+  GST_BASE_PARSE_SEEK_DEFAULT,
+  GST_BASE_PARSE_SEEK_TABLE
+} GstBaseParseSeekable;
+
+typedef struct _GstBaseParse GstBaseParse;
+typedef struct _GstBaseParseClass GstBaseParseClass;
+typedef struct _GstBaseParsePrivate GstBaseParsePrivate;
+
+/**
+ * GstBaseParse:
+ * @element: the parent element.
+ *
+ * The opaque #GstBaseParse data structure.
+ */
+struct _GstBaseParse {
+  GstElement     element;
+  GstAdapter    *adapter;
+
+  /*< protected >*/
+  /* source and sink pads */
+  GstPad         *sinkpad;
+  GstPad         *srcpad;
+
+  /* MT-protected (with STREAM_LOCK) */
+  GstSegment      segment;
+
+  /* Newsegment event to be sent after SEEK */
+  GstEvent       *pending_segment;
+
+  /* Segment event that closes the running segment prior to SEEK */
+  GstEvent       *close_segment;
+
+  /*< private >*/
+  gpointer       _gst_reserved[GST_PADDING_LARGE];
+  GstBaseParsePrivate *priv;
+};
+
+/**
+ * GstBaseParseClass:
+ * @start:          Optional.
+ *                  Called when the element starts processing.
+ *                  Allows opening external resources.
+ * @stop:           Optional.
+ *                  Called when the element stops processing.
+ *                  Allows closing external resources.
+ * @set_sink_caps:  allows the subclass to be notified of the actual caps set.
+ * @check_valid_frame:  Check if the given piece of data contains a valid
+ *                      frame.
+ * @parse_frame:    Parse the already checked frame. Subclass need to
+ *                  set the buffer timestamp, duration, caps and possibly
+ *                  other necessary metadata. This is called with srcpad's
+ *                  STREAM_LOCK held.
+ * @convert:        Optional.
+ *                  Convert between formats.
+ * @find_frame:     Optional.
+ *                  Finds a frame. Gets a position passed and should return
+ *                  TRUE and the offset in bytes where this position is.
+ *                  Will only be called in pull mode and the subclass can pull
+ *                  whatever it wants from upstream. If not implemented,
+ *                  the base class will implement it by calling
+ *                  @check_valid_frame and @parse_frame to find the wanted
+ *                  frame and build a seek table.
+ * @event:          Optional.
+ *                  Event handler on the sink pad. This function should return
+ *                  TRUE if the event was handled and can be dropped.
+ * @src_event:      Optional.
+ *                  Event handler on the source pad. Should return TRUE
+ *                  if the event was handled and can be dropped.
+ *
+ * @get_frame_overhead: Finds the metadata overhead for the given frame. This
+ *                      is used to enable more accurate bitrate computations.
+ *                      If NULL, the per-frame overhead is assumed to be 0. If
+ *                      this returns -1, it is assumed that this frame should
+ *                      be skipped in bitrate calculation.
+ *
+ * @pre_push_buffer: Optional.
+ *                   Called just prior to pushing a frame (after any pending
+ *                   events have been sent) to give subclass a chance to perform
+ *                   additional actions at this time (e.g. tag sending) or to
+ *                   decide whether this buffer should be dropped or not
+ *                   (e.g. custom segment clipping).
+ *
+ * Subclasses can override any of the available virtual methods or not, as
+ * needed. At minimum @check_valid_frame and @parse_frame needs to be
+ * overridden.
+ */
+struct _GstBaseParseClass {
+  GstElementClass parent_class;
+
+  /*< public >*/
+  /* virtual methods for subclasses */
+
+  gboolean      (*start)              (GstBaseParse *parse);
+
+  gboolean      (*stop)               (GstBaseParse *parse);
+
+  gboolean      (*set_sink_caps)      (GstBaseParse *parse,
+                                       GstCaps *caps);
+
+  gboolean      (*check_valid_frame)  (GstBaseParse *parse,
+                                       GstBaseParseFrame *frame,
+                                       guint *framesize,
+                                       gint *skipsize);
+
+  GstFlowReturn (*parse_frame)        (GstBaseParse *parse,
+                                       GstBaseParseFrame *frame);
+
+  GstFlowReturn (*pre_push_frame)     (GstBaseParse *parse,
+                                       GstBaseParseFrame *frame);
+
+  gboolean      (*convert)            (GstBaseParse * parse,
+                                       GstFormat src_format,
+                                       gint64 src_value,
+                                       GstFormat dest_format,
+                                       gint64 * dest_value);
+
+  gboolean      (*event)              (GstBaseParse *parse,
+                                       GstEvent *event);
+
+  gboolean      (*src_event)          (GstBaseParse *parse,
+                                       GstEvent *event);
+
+  /*< private >*/
+  gpointer       _gst_reserved[GST_PADDING_LARGE];
+};
+
+GType           gst_base_parse_get_type         (void);
+
+void            gst_base_parse_frame_init (GstBaseParse * parse,
+                                           GstBaseParseFrame * frame);
+GstFlowReturn   gst_base_parse_push_frame (GstBaseParse *parse,
+                                           GstBaseParseFrame *frame);
+
+void            gst_base_parse_set_duration (GstBaseParse *parse,
+                                             GstFormat fmt, gint64 duration,
+                                              gint interval);
+void            gst_base_parse_set_seek (GstBaseParse * parse,
+                                         GstBaseParseSeekable seek,
+                                         guint bitrate);
+void            gst_base_parse_set_min_frame_size (GstBaseParse *parse,
+                                                   guint min_size);
+void            gst_base_parse_set_format (GstBaseParse * parse,
+                                           GstBaseParseFormat flag,
+                                           gboolean on);
+void            gst_base_parse_set_frame_props (GstBaseParse * parse,
+                                                guint fps_num, guint fps_den,
+                                                guint lead_in, guint lead_out);
+
+gboolean        gst_base_parse_convert_default (GstBaseParse * parse,
+                                                GstFormat src_format, gint64 src_value,
+                                                GstFormat dest_format, gint64 * dest_value);
+
+gboolean        gst_base_parse_add_index_entry (GstBaseParse * parse,
+                                                guint64 offset, GstClockTime ts,
+                                                gboolean key, gboolean force);
+
+G_END_DECLS
+
+#endif /* __GST_BASE_PARSE_H__ */