| /* GStreamer |
| * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu> |
| * 2005 Wim Taymans <wim@fluendo.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., 51 Franklin St, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| */ |
| |
| #ifndef __GST_BASE_TRANSFORM_H__ |
| #define __GST_BASE_TRANSFORM_H__ |
| |
| #include <gst/gst.h> |
| |
| G_BEGIN_DECLS |
| |
| #define GST_TYPE_BASE_TRANSFORM (gst_base_transform_get_type()) |
| #define GST_BASE_TRANSFORM(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BASE_TRANSFORM,GstBaseTransform)) |
| #define GST_BASE_TRANSFORM_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_BASE_TRANSFORM,GstBaseTransformClass)) |
| #define GST_BASE_TRANSFORM_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS((obj),GST_TYPE_BASE_TRANSFORM,GstBaseTransformClass)) |
| #define GST_IS_BASE_TRANSFORM(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BASE_TRANSFORM)) |
| #define GST_IS_BASE_TRANSFORM_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_BASE_TRANSFORM)) |
| #define GST_BASE_TRANSFORM_CAST(obj) ((GstBaseTransform *)(obj)) |
| |
| /** |
| * GST_BASE_TRANSFORM_SINK_NAME: |
| * |
| * The name of the templates for the sink pad. |
| */ |
| #define GST_BASE_TRANSFORM_SINK_NAME "sink" |
| /** |
| * GST_BASE_TRANSFORM_SRC_NAME: |
| * |
| * The name of the templates for the source pad. |
| */ |
| #define GST_BASE_TRANSFORM_SRC_NAME "src" |
| |
| /** |
| * GST_BASE_TRANSFORM_SRC_PAD: |
| * @obj: base transform instance |
| * |
| * Gives the pointer to the source #GstPad object of the element. |
| */ |
| #define GST_BASE_TRANSFORM_SRC_PAD(obj) (GST_BASE_TRANSFORM_CAST (obj)->srcpad) |
| |
| /** |
| * GST_BASE_TRANSFORM_SINK_PAD: |
| * @obj: base transform instance |
| * |
| * Gives the pointer to the sink #GstPad object of the element. |
| */ |
| #define GST_BASE_TRANSFORM_SINK_PAD(obj) (GST_BASE_TRANSFORM_CAST (obj)->sinkpad) |
| |
| /** |
| * GST_BASE_TRANSFORM_FLOW_DROPPED: |
| * |
| * A #GstFlowReturn that can be returned from transform and transform_ip to |
| * indicate that no output buffer was generated. |
| */ |
| #define GST_BASE_TRANSFORM_FLOW_DROPPED GST_FLOW_CUSTOM_SUCCESS |
| |
| typedef struct _GstBaseTransform GstBaseTransform; |
| typedef struct _GstBaseTransformClass GstBaseTransformClass; |
| typedef struct _GstBaseTransformPrivate GstBaseTransformPrivate; |
| |
| /** |
| * GstBaseTransform: |
| * |
| * The opaque #GstBaseTransform data structure. |
| */ |
| struct _GstBaseTransform { |
| GstElement element; |
| |
| /*< protected >*/ |
| /* source and sink pads */ |
| GstPad *sinkpad; |
| GstPad *srcpad; |
| |
| /* MT-protected (with STREAM_LOCK) */ |
| gboolean have_segment; |
| GstSegment segment; |
| /* Default submit_input_buffer places the buffer here, |
| * for consumption by the generate_output method: */ |
| GstBuffer *queued_buf; |
| |
| /*< private >*/ |
| GstBaseTransformPrivate *priv; |
| |
| gpointer _gst_reserved[GST_PADDING_LARGE-1]; |
| }; |
| |
| /** |
| * GstBaseTransformClass: |
| * @parent_class: Element parent class |
| * @passthrough_on_same_caps: If set to %TRUE, passthrough mode will be |
| * automatically enabled if the caps are the same. |
| * Set to %FALSE by default. |
| * @transform_ip_on_passthrough: If set to %TRUE, @transform_ip will be called in |
| * passthrough mode. The passed buffer might not be |
| * writable. When %FALSE, neither @transform nor |
| * @transform_ip will be called in passthrough mode. |
| * Set to %TRUE by default. |
| * @transform_caps: Optional. Given the pad in this direction and the given |
| * caps, what caps are allowed on the other pad in this |
| * element ? |
| * @fixate_caps: Optional. Given the pad in this direction and the given |
| * caps, fixate the caps on the other pad. The function takes |
| * ownership of @othercaps and returns a fixated version of |
| * @othercaps. @othercaps is not guaranteed to be writable. |
| * @accept_caps: Optional. |
| * Subclasses can override this method to check if @caps can be |
| * handled by the element. The default implementation might not be |
| * the most optimal way to check this in all cases. |
| * @set_caps: allows the subclass to be notified of the actual caps set. |
| * @query: Optional. |
| * Handle a requested query. Subclasses that implement this |
| * should must chain up to the parent if they didn't handle the |
| * query |
| * @decide_allocation: Setup the allocation parameters for allocating output |
| * buffers. The passed in query contains the result of the |
| * downstream allocation query. This function is only called |
| * when not operating in passthrough mode. The default |
| * implementation will remove all memory dependent metadata. |
| * If there is a @filter_meta method implementation, it will |
| * be called for all metadata API in the downstream query, |
| * otherwise the metadata API is removed. |
| * @filter_meta: Return %TRUE if the metadata API should be proposed in the |
| * upstream allocation query. The default implementation is %NULL |
| * and will cause all metadata to be removed. |
| * @propose_allocation: Propose buffer allocation parameters for upstream elements. |
| * This function must be implemented if the element reads or |
| * writes the buffer content. The query that was passed to |
| * the decide_allocation is passed in this method (or %NULL |
| * when the element is in passthrough mode). The default |
| * implementation will pass the query downstream when in |
| * passthrough mode and will copy all the filtered metadata |
| * API in non-passthrough mode. |
| * @transform_size: Optional. Given the size of a buffer in the given direction |
| * with the given caps, calculate the size in bytes of a buffer |
| * on the other pad with the given other caps. |
| * The default implementation uses get_unit_size and keeps |
| * the number of units the same. |
| * @get_unit_size: Required if the transform is not in-place. |
| * get the size in bytes of one unit for the given caps. |
| * @start: Optional. |
| * Called when the element starts processing. |
| * Allows opening external resources. |
| * @stop: Optional. |
| * Called when the element stops processing. |
| * Allows closing external resources. |
| * @sink_event: Optional. |
| * Event handler on the sink pad. The default implementation |
| * handles the event and forwards it downstream. |
| * @src_event: Optional. |
| * Event handler on the source pad. The default implementation |
| * handles the event and forwards it upstream. |
| * @prepare_output_buffer: Optional. |
| * Subclasses can override this to do their own |
| * allocation of output buffers. Elements that only do |
| * analysis can return a subbuffer or even just |
| * return a reference to the input buffer (if in |
| * passthrough mode). The default implementation will |
| * use the negotiated allocator or bufferpool and |
| * transform_size to allocate an output buffer or it |
| * will return the input buffer in passthrough mode. |
| * @copy_metadata: Optional. |
| * Copy the metadata from the input buffer to the output buffer. |
| * The default implementation will copy the flags, timestamps and |
| * offsets of the buffer. |
| * @transform_meta: Optional. Transform the metadata on the input buffer to the |
| * output buffer. By default this method copies all meta without |
| * tags. subclasses can implement this method and return %TRUE if |
| * the metadata is to be copied. |
| * @before_transform: Optional. |
| * This method is called right before the base class will |
| * start processing. Dynamic properties or other delayed |
| * configuration could be performed in this method. |
| * @transform: Required if the element does not operate in-place. |
| * Transforms one incoming buffer to one outgoing buffer. |
| * The function is allowed to change size/timestamp/duration |
| * of the outgoing buffer. |
| * @transform_ip: Required if the element operates in-place. |
| * Transform the incoming buffer in-place. |
| * @submit_input_buffer: Function which accepts a new input buffer and pre-processes it. |
| * The default implementation performs caps (re)negotiation, then |
| * QoS if needed, and places the input buffer into the @queued_buf |
| * member variable. If the buffer is dropped due to QoS, it returns |
| * GST_BASE_TRANSFORM_FLOW_DROPPED. If this input buffer is not |
| * contiguous with any previous input buffer, then @is_discont |
| * is set to #TRUE. (Since 1.6) |
| * @generate_output: Called after each new input buffer is submitted repeatedly |
| * until it either generates an error or fails to generate an output |
| * buffer. The default implementation takes the contents of the |
| * @queued_buf variable, generates an output buffer if needed |
| * by calling the class @prepare_output_buffer, and then |
| * calls either @transform or @transform_ip. Elements that don't |
| * do 1-to-1 transformations on input to output buffers can either |
| * return GST_BASE_TRANSFORM_FLOW_DROPPED or simply not generate |
| * an output buffer until they are ready to do so. (Since 1.6) |
| * |
| * Subclasses can override any of the available virtual methods or not, as |
| * needed. At minimum either @transform or @transform_ip need to be overridden. |
| * If the element can overwrite the input data with the results (data is of the |
| * same type and quantity) it should provide @transform_ip. |
| */ |
| struct _GstBaseTransformClass { |
| GstElementClass parent_class; |
| |
| /*< public >*/ |
| gboolean passthrough_on_same_caps; |
| gboolean transform_ip_on_passthrough; |
| |
| /* virtual methods for subclasses */ |
| GstCaps* (*transform_caps) (GstBaseTransform *trans, |
| GstPadDirection direction, |
| GstCaps *caps, GstCaps *filter); |
| GstCaps* (*fixate_caps) (GstBaseTransform *trans, |
| GstPadDirection direction, GstCaps *caps, |
| GstCaps *othercaps); |
| gboolean (*accept_caps) (GstBaseTransform *trans, GstPadDirection direction, |
| GstCaps *caps); |
| gboolean (*set_caps) (GstBaseTransform *trans, GstCaps *incaps, |
| GstCaps *outcaps); |
| gboolean (*query) (GstBaseTransform *trans, GstPadDirection direction, |
| GstQuery *query); |
| |
| /* decide allocation query for output buffers */ |
| gboolean (*decide_allocation) (GstBaseTransform *trans, GstQuery *query); |
| gboolean (*filter_meta) (GstBaseTransform *trans, GstQuery *query, |
| GType api, const GstStructure *params); |
| |
| /* propose allocation query parameters for input buffers */ |
| gboolean (*propose_allocation) (GstBaseTransform *trans, GstQuery *decide_query, |
| GstQuery *query); |
| |
| /* transform size */ |
| gboolean (*transform_size) (GstBaseTransform *trans, |
| GstPadDirection direction, |
| GstCaps *caps, gsize size, |
| GstCaps *othercaps, gsize *othersize); |
| |
| gboolean (*get_unit_size) (GstBaseTransform *trans, GstCaps *caps, |
| gsize *size); |
| |
| /* states */ |
| gboolean (*start) (GstBaseTransform *trans); |
| gboolean (*stop) (GstBaseTransform *trans); |
| |
| /* sink and src pad event handlers */ |
| gboolean (*sink_event) (GstBaseTransform *trans, GstEvent *event); |
| gboolean (*src_event) (GstBaseTransform *trans, GstEvent *event); |
| |
| GstFlowReturn (*prepare_output_buffer) (GstBaseTransform * trans, |
| GstBuffer *input, GstBuffer **outbuf); |
| |
| /* metadata */ |
| gboolean (*copy_metadata) (GstBaseTransform *trans, GstBuffer *input, |
| GstBuffer *outbuf); |
| gboolean (*transform_meta) (GstBaseTransform *trans, GstBuffer *outbuf, |
| GstMeta *meta, GstBuffer *inbuf); |
| |
| void (*before_transform) (GstBaseTransform *trans, GstBuffer *buffer); |
| |
| /* transform */ |
| GstFlowReturn (*transform) (GstBaseTransform *trans, GstBuffer *inbuf, |
| GstBuffer *outbuf); |
| GstFlowReturn (*transform_ip) (GstBaseTransform *trans, GstBuffer *buf); |
| |
| GstFlowReturn (*submit_input_buffer) (GstBaseTransform *trans, gboolean is_discont, GstBuffer *input); |
| GstFlowReturn (*generate_output) (GstBaseTransform *trans, GstBuffer **outbuf); |
| |
| /*< private >*/ |
| gpointer _gst_reserved[GST_PADDING_LARGE - 2]; |
| }; |
| |
| GType gst_base_transform_get_type (void); |
| |
| void gst_base_transform_set_passthrough (GstBaseTransform *trans, |
| gboolean passthrough); |
| gboolean gst_base_transform_is_passthrough (GstBaseTransform *trans); |
| |
| void gst_base_transform_set_in_place (GstBaseTransform *trans, |
| gboolean in_place); |
| gboolean gst_base_transform_is_in_place (GstBaseTransform *trans); |
| |
| void gst_base_transform_update_qos (GstBaseTransform *trans, |
| gdouble proportion, |
| GstClockTimeDiff diff, |
| GstClockTime timestamp); |
| void gst_base_transform_set_qos_enabled (GstBaseTransform *trans, |
| gboolean enabled); |
| gboolean gst_base_transform_is_qos_enabled (GstBaseTransform *trans); |
| |
| void gst_base_transform_set_gap_aware (GstBaseTransform *trans, |
| gboolean gap_aware); |
| |
| void gst_base_transform_set_prefer_passthrough (GstBaseTransform *trans, |
| gboolean prefer_passthrough); |
| |
| GstBufferPool * gst_base_transform_get_buffer_pool (GstBaseTransform *trans); |
| void gst_base_transform_get_allocator (GstBaseTransform *trans, |
| GstAllocator **allocator, |
| GstAllocationParams *params); |
| |
| void gst_base_transform_reconfigure_sink (GstBaseTransform *trans); |
| void gst_base_transform_reconfigure_src (GstBaseTransform *trans); |
| gboolean gst_base_transform_update_src_caps (GstBaseTransform *trans, |
| GstCaps *updated_caps); |
| G_END_DECLS |
| |
| #endif /* __GST_BASE_TRANSFORM_H__ */ |
