mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
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299 lines
4.4 KiB
Text
299 lines
4.4 KiB
Text
<!-- ##### SECTION Title ##### -->
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GstBuffer
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<!-- ##### SECTION Short_Description ##### -->
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Data-passing buffer type, supporting sub-buffers and metadata
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<!-- ##### SECTION Long_Description ##### -->
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<para>
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Buffers are the basic unit of data transfer in GST. The GstBuffer type
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provides all the state necessary to define a region of memory as part of a
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stream. Sub-buffer are also supported, allowing a smaller region of a
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buffer to become its own buffer, with mechanisms in place to ensure that
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nither memory space goes away. Metadata is supported as a list of
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pointers to arbitrary metadata.
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</para>
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<!-- ##### SECTION See_Also ##### -->
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<para>
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</para>
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<!-- ##### MACRO GST_BUFFER_FLAGS ##### -->
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<para>
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get the flags from this buffer
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</para>
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@buf: GstBuffer to retrieve the flags from
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<!-- ##### MACRO GST_BUFFER_FLAG_IS_SET ##### -->
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<para>
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gives the status of a given flag
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</para>
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@buf: GstBuffer to query
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@flag: the flag to check
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<!-- ##### MACRO GST_BUFFER_FLAG_SET ##### -->
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<para>
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set a flag in a buffer
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</para>
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@buf: GstBuffer to query
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@flag: the flag to set
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<!-- ##### MACRO GST_BUFFER_FLAG_UNSET ##### -->
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<para>
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clear a flag in a buffer
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</para>
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@buf: GstBuffer to modify
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@flag: the flag to clear
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<!-- ##### MACRO GST_BUFFER_TYPE ##### -->
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<para>
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Retrieves the type id of the data in the buffer.
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</para>
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@buf: GstBuffer
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<!-- ##### MACRO GST_BUFFER_DATA ##### -->
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<para>
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retrieves a pointer to the data element of this buffer
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</para>
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@buf: GstBuffer
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<!-- ##### MACRO GST_BUFFER_SIZE ##### -->
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<para>
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get the size of the data in this buffer
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</para>
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@buf: GstBuffer
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<!-- ##### MACRO GST_BUFFER_OFFSET ##### -->
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<para>
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</para>
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@buf: GstBuffer
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<!-- ##### MACRO GST_BUFFER_MAXSIZE ##### -->
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<para>
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</para>
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@buf: GstBuffer
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<!-- ##### MACRO GST_BUFFER_TIMESTAMP ##### -->
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<para>
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get the timestamp for this buffer
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</para>
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@buf: GstBuffer
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<!-- ##### MACRO GST_BUFFER_LOCK ##### -->
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<para>
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This macro will obtain a lock on the object, making serialization
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possible.
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</para>
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@buf: GstBuffer to lock
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<!-- ##### MACRO GST_BUFFER_TRYLOCK ##### -->
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<para>
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This macro will try to obtain a lock on the object, but will return with
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FALSE if it can't get it immediately.
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</para>
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@buf: GstBuffer to try to lock
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<!-- ##### MACRO GST_BUFFER_UNLOCK ##### -->
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<para>
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this macro releases a lock on the object.
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</para>
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@buf: GstBuffer to unlock.
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<!-- ##### ENUM GstBufferFlags ##### -->
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<para>
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<informaltable pgwide=1 frame="none" role="enum">
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<tgroup cols="2"><colspec colwidth="2*"><colspec colwidth="8*">
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<tbody>
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<row>
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<entry>GST_BUFFER_READONLY</entry>
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<entry>the buffer is read only</entry>
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</row>
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<row>
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<entry>GST_BUFFER_EOS</entry>
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<entry>this buffer is the last one in the stream</entry>
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</row>
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<row>
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<entry>GST_BUFFER_ORIGINAL</entry>
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<entry>this buffer not a copy</entry>
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</row>
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<row>
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<entry>GST_BUFFER_DONTFREE</entry>
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<entry>do not try to free the data when this buffer is unref-ed</entry>
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</row>
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<row>
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<entry>GST_BUFFER_FLUSH</entry>
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<entry>this buffer is not related to previous buffers. This flag is mainly
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used when data in a stream has been skipped</entry>
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</row>
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</tbody></tgroup></informaltable>
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</para>
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@GST_BUFFER_READONLY:
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@GST_BUFFER_EOS:
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@GST_BUFFER_ORIGINAL:
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@GST_BUFFER_DONTFREE:
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@GST_BUFFER_FLUSH:
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<!-- ##### STRUCT GstBuffer ##### -->
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<para>
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</para>
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@lock:
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@flags:
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@data:
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@size:
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@maxsize:
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@offset:
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@timestamp:
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@maxage:
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@metas:
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@parent:
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@pool:
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<!-- ##### FUNCTION gst_buffer_new ##### -->
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<para>
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</para>
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@Returns:
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<!-- ##### FUNCTION gst_buffer_new_from_pool ##### -->
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<para>
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</para>
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@pool:
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@Returns:
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<!-- ##### FUNCTION gst_buffer_create_sub ##### -->
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<para>
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</para>
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@parent:
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@offset:
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@size:
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@Returns:
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<!-- ##### FUNCTION gst_buffer_append ##### -->
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<para>
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</para>
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@buffer:
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@append:
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@Returns:
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<!-- ##### FUNCTION gst_buffer_ref ##### -->
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<para>
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</para>
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@buffer:
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<!-- ##### FUNCTION gst_buffer_ref_by_count ##### -->
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<para>
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</para>
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@buffer:
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@count:
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<!-- ##### FUNCTION gst_buffer_unref ##### -->
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<para>
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</para>
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@buffer:
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<!-- ##### FUNCTION gst_buffer_destroy ##### -->
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<para>
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</para>
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@buffer:
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<!-- ##### FUNCTION gst_buffer_add_meta ##### -->
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<para>
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</para>
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@buffer:
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@meta:
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<!-- ##### FUNCTION gst_buffer_get_first_meta ##### -->
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<para>
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</para>
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@buffer:
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@Returns:
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<!-- ##### FUNCTION gst_buffer_get_metas ##### -->
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<para>
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</para>
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@buffer:
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@Returns:
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<!-- ##### FUNCTION gst_buffer_remove_meta ##### -->
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<para>
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</para>
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@buffer:
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@meta:
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