gstreamer/subprojects/gst-plugins-bad/gst/frei0r/frei0r.h

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/** @mainpage frei0r - a minimalistic plugin API for video effects
*
* @section sec_intro Introduction
*
* This is frei0r - a minimalistic plugin API for video effects.
*
* The main emphasis is on simplicity - there are many different applications
* that use video effects, and they all have different requirements regarding
* their internal plugin API. And that's why frei0r does not try to be a
* one-in-all general video plugin API, but instead an API for the most
* common video effects: simple filters, sources and mixers that can be
* controlled by parameters.
*
* It's our hope that this way these simple effects can be shared between
* many applications, avoiding their reimplementation by different
* projects.
*
* On the other hand, this is not meant as a competing standard to
* more ambitious efforts that try to satisfy the needs of many different
* applications and more complex effects.
*
*
* @section sec_overview Overview
*
* If you are new to frei0r, the best thing is probably to have
* a look at the <a href="frei0r_8h-source.html">frei0r header</a>,
* which is quite simple.
*
* After that, you might want to look at the
* <a href="frei0r_8h.html">frei0r functions</a> in more detail.
*
* When developing a new frei0r effect, you have to choose
* - which effect type to use (\ref PLUGIN_TYPE),
* - which color model to use (\ref COLOR_MODEL), and
* - which parameter types (\ref PARAM_TYPE) your effect will support.
*
* To round things up, you should decide whether your effect should have
* an associated icon (\ref icons), and where it will be installed
* (\ref pluglocations).
*
* @section sec_changes Changes
*
* @subsection sec_changes_1_1_1_2 From frei0r 1.1 to frei0r 1.2
* - make <vendor> in plugin path optional
* - added section on FREI0R_PATH environment variable
* - added requirement to initialize all parameters in f0r_construct()
*
* @subsection sec_changes_1_0_1_1 From frei0r 1.0 to frei0r 1.1
*
* - added specifications for plugin locations
* - added specifications for frei0r icons
* - added RGBA8888 color model
* - added packed32 color model
* - added better specification of color models
* - added string type
* - added bounds to resolution (8 <= width, height <= 2048)
* - width and height must be an integer multiple of 8
* - frame data must be 16 byte aligned
* - improved update specification (must not change parameters,
* must restore fpu state)
* - added note for applications to ignore effects with unknown fields
* - added new plugin types mixer2 and mixer3
* - added section about \ref concurrency
*/
/**
* \addtogroup pluglocations Plugin Locations
* @section sec_pluglocations Plugin Locations
*
* For Unix platforms there are rules for the location of frei0r plugins.
*
* frei0r 1.x plugin files should be located in
*
* - (1) /usr/lib/frei0r-1/\<vendor\>
* - (2) /usr/local/lib/frei0r-1/\<vendor\>
* - (3) $HOME/.frei0r-1/lib/\<vendor\>
*
* Examples:
*
* - /usr/lib/frei0r-1/mob/flippo.so
* - /usr/lib/frei0r-1/drone/flippo.so
* - /usr/local/lib/frei0r-1/gephex/coma/invert0r.so
* - /home/martin/.frei0r-1/lib/martin/test.so
*
* Like in these examples plugins should be placed in "vendor" subdirs
* to reduce name clashes. However, <vendor> is optional and may be left blank.
*
* @subsection sec_order Plugin Loading Order
*
* The application shall load plugins in the following order: 3, 2, 1.
* If a name clash occurs (two or more frei0r plugins with identical
* effect name), the plugins in directory 3 have precedence over plugins
* in directory 2, and those in directory 2 have precedence over plugins
* in directory 1.
*
* This makes it possible for users to "override" effects that are
* installed in system wide directories by placing plugins in their
* home directory.
*
* The order of loading plugins inside each of the directories
* 1, 2, and 3 is not defined.
*
* @subsection sec_path FREI0R_PATH Environment Variable
*
* If the environment variable FREI0R_PATH is defined, then it shall be
* considered a colon separated list of directories which replaces the
* default list.
*
* For example:
*
* FREI0R_PATH=/home/foo/frei0r-plugins:/usr/lib/frei0r-1:/etc/frei0r
*/
/**
*\addtogroup icons Icons for frei0r effects
* @section sec_icons Icons for frei0r effects
*
* Each frei0r effect can have an associated icon.
*
* @subsection sec_icon_format Icon Format
*
* The format of frei0r icons must be png.
* Recommended resolution is 64x64.
* The icon filename of an effect with effect name "frei0r"
* must be "frei0r.png".
*
* @subsection sec_icon_location Icon location
*
* The exact location where the application should look for the
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* plugin is platform dependent.
*
* For Windows platforms, the icon should be at the same place as
* the plugin containing the effect.
*
* For Unix platforms, the following mapping from plugin location
* to icon location must be used:
*
* Let \<plugin_path\>/\<plugin\> be a frei0r plugin with name \<effect_name\>.
* Then the corresponding icon (if any) shall be located in
* \<icon_path\>/\<effect_name\>.png.
* \<icon_path\> can be obtained in the following way:
*
* @verbatim
<plugin_path> | <icon_path>
----------------------------------------------------------------------------
$HOME/.frei0r-1/lib/<vendor> | $HOME/.frei0r-1/icons/<vendor>
/usr/local/lib/frei0r-1/<vendor> | /usr/local/share/frei0r-1/icons/<vendor>
/usr/lib/frei0r-1/<vendor> | /usr/share/frei0r-1/icons/<vendor>
* | <plugin_path>
@endverbatim
*
* (The wildcard '*' stands for any other plugin_path)
*
* For other platforms, no location is defined. We recommend to use the
* plugin path where possible.
*/
/**
* \addtogroup concurrency Concurrency
* @section sec_concurrency Concurrency
*
* - \ref f0r_init
* - \ref f0r_deinit
*
* These methods must not be called more than once. It is obvious that no
* concurrent calls are allowed.
*
*
* - \ref f0r_get_plugin_info
* - \ref f0r_get_param_info
* - \ref f0r_construct
* - \ref f0r_destruct
*
* Concurrent calls of these functions are allowed.
*
*
* - \ref f0r_set_param_value
* - \ref f0r_get_param_value
* - \ref f0r_update
* - \ref f0r_update2
*
* If a thread is in one of these methods its allowed for another thread to
* enter one of theses methods for a different effect instance. But for one
* effect instance only one thread is allowed to execute any of these methods.
*/
/** \file
* \brief This file defines the frei0r api, version 1.2.
*
* A conforming plugin must implement and export all functions declared in
* this header.
*
* A conforming application must accept only those plugins which use
* allowed values for the described fields.
*/
#ifndef INCLUDED_FREI0R_H
#define INCLUDED_FREI0R_H
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#include <glib.h>
/**
* The frei0r API major version
*/
#define FREI0R_MAJOR_VERSION 1
/**
* The frei0r API minor version
*/
#define FREI0R_MINOR_VERSION 2
//---------------------------------------------------------------------------
/**
* f0r_init() is called once when the plugin is loaded by the application.
* \see f0r_deinit
*/
int f0r_init();
/**
* f0r_deinit is called once when the plugin is unloaded by the application.
* \see f0r_init
*/
void f0r_deinit();
//---------------------------------------------------------------------------
/** \addtogroup PLUGIN_TYPE Type of the Plugin
* These defines determine whether the plugin is a
* source, a filter or one of the two mixer types
* @{
*/
/** one input and one output */
#define F0R_PLUGIN_TYPE_FILTER 0
/** just one output */
#define F0R_PLUGIN_TYPE_SOURCE 1
/** two inputs and one output */
#define F0R_PLUGIN_TYPE_MIXER2 2
/** three inputs and one output */
#define F0R_PLUGIN_TYPE_MIXER3 3
/** @} */
//---------------------------------------------------------------------------
/** \addtogroup COLOR_MODEL Color Models
* List of supported color models.
*
* Note: the color models are endian independent, because the
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* color components are defined by their position in memory, not
* by their significance in an uint32_t value.
*
* For effects that work on the color components,
* RGBA8888 is the recommended color model for frei0r-1.2 effects.
* For effects that only work on pixels, PACKED32 is the recommended
* color model since it helps the application to avoid unnecessary
* color conversions.
*
* Effects can choose an appropriate color model, applications must support
* all color models and do conversions if necessary. Source effects
* must not use the PACKED32 color model because the application must know
* in which color model the created framebuffers are represented.
*
* For each color model, a frame consists of width*height pixels which
* are stored row-wise and consecutively in memory. The size of a pixel is
* 4 bytes. There is no extra pitch parameter
* (i.e. the pitch is simply width*4).
*
* The following additional constraints must be honored:
* - The top-most line of a frame is stored first in memory.
* - A frame must be aligned to a 16 byte border in memory.
* - The width and height of a frame must be positive
* - The width and height of a frame must be integer multiples of 8
*
* These constraints make sure that each line is stored at an address aligned
* to 16 byte.
*/
/*@{*/
/**
* In BGRA8888, each pixel is represented by 4 consecutive
* unsigned bytes, where the first byte value represents
* the blue, the second the green, and the third the red color
* component of the pixel. The last value represents the
* alpha value.
*/
#define F0R_COLOR_MODEL_BGRA8888 0
/**
* In RGBA8888, each pixel is represented by 4 consecutive
* unsigned bytes, where the first byte value represents
* the red, the second the green, and the third the blue color
* component of the pixel. The last value represents the
* alpha value.
*/
#define F0R_COLOR_MODEL_RGBA8888 1
/**
* In PACKED32, each pixel is represented by 4 consecutive
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* bytes, but it is not defined how the color components are
* stored. The true color format could be RGBA8888,
* BGRA8888, a packed 32 bit YUV format, or any other
* color format that stores pixels in 32 bit.
*
* This is useful for effects that don't work on color but
* only on pixels (for example a mirror effect).
*
* Note that source effects must not use this color model.
*/
#define F0R_COLOR_MODEL_PACKED32 2
/*@}*/
/**
* The f0r_plugin_info_t structure is filled in by the plugin
* to tell the application about its name, type, number of parameters,
* and version.
*
* An application should ignore (i.e. not use) frei0r effects that
* have unknown values in the plugin_type or color_model field.
* It should also ignore effects with a too high frei0r_version.
*
* This is necessary to be able to extend the frei0r spec (e.g.
* by adding new color models or plugin types) in a way that does not
* result in crashes when loading effects that make use of these
* extensions into an older application.
*
* All strings are unicode, 0-terminated, and the encoding is utf-8.
*/
typedef struct f0r_plugin_info
{
const char* name; /**< The (short) name of the plugin */
const char* author; /**< The plugin author */
/** The plugin type
* \see PLUGIN_TYPE
*/
int plugin_type;
int color_model; /**< The color model used */
int frei0r_version; /**< The frei0r major version this plugin is built for*/
int major_version; /**< The major version of the plugin */
int minor_version; /**< The minor version of the plugin */
int num_params; /**< The number of parameters of the plugin */
const char* explanation; /**< An optional explanation string */
} f0r_plugin_info_t;
/**
* Is called once after init. The plugin has to fill in the values in info.
*
* \param info Pointer to an info struct allocated by the application.
*/
void f0r_get_plugin_info(f0r_plugin_info_t* info);
//---------------------------------------------------------------------------
/** \addtogroup PARAM_TYPE Parameter Types
*
* @{
*/
/**
* Parameter type for boolean values
* \see f0r_param_bool
*/
#define F0R_PARAM_BOOL 0
/**
* Parameter type for doubles
* \see f0r_param_double
*/
#define F0R_PARAM_DOUBLE 1
/**
* Parameter type for color
* \see f0r_param_color
*/
#define F0R_PARAM_COLOR 2
/**
* Parameter type for position
* \see f0r_param_position
*/
#define F0R_PARAM_POSITION 3
/**
* Parameter type for string
* \see f0r_param_string
*/
#define F0R_PARAM_STRING 4
/**
* The boolean type. The allowed range of values is [0, 1].
* [0, 0.5[ is mapped to false and [0.5, 1] is mapped to true.
*/
typedef double f0r_param_bool;
/**
* The double type. The allowed range of values is [0, 1].
*/
typedef double f0r_param_double;
/**
* The color type. All three color components are in the range [0, 1].
*/
typedef struct f0r_param_color
{
float r; /**< red color component */
float g; /**< green color component */
float b; /**< blue color component */
} f0r_param_color_t;
/**
* The position type. Both position coordinates are in the range [0, 1].
*/
typedef struct f0r_param_position
{
double x; /**< x coordinate */
double y; /**< y coordinate */
} f0r_param_position_t;
/**
* The string type.
* Zero terminated array of 8-bit values in utf-8 encoding
*/
typedef char f0r_param_string;
/** @} */
/**
* Similar to f0r_plugin_info_t, this structure is filled by the plugin
* for every parameter.
*
* All strings are unicode, 0-terminated, and the encoding is utf-8.
*/
typedef struct f0r_param_info
{
const char* name; /**<The (short) name of the param */
int type; /**<The type (see the F0R_PARAM_* defines) */
const char* explanation; /**<Optional explanation (can be 0) */
} f0r_param_info_t;
/**
* f0r_get_param_info is called by the application to query the type of
* each parameter.
*
* \param info is allocated by the application and filled by the plugin
* \param param_index the index of the parameter to be queried (from 0 to
* num_params-1)
*/
void f0r_get_param_info(f0r_param_info_t* info, int param_index);
//---------------------------------------------------------------------------
/**
* Transparent instance pointer of the frei0r effect.
*/
typedef void* f0r_instance_t;
/**
* Constructor for effect instances. The plugin returns a pointer to
* its internal instance structure.
*
* The resolution must be an integer multiple of 8,
* must be greater than 0 and be at most 2048 in both dimensions.
* The plugin must set default values for all parameters in this function.
*
* \param width The x-resolution of the processed video frames
* \param height The y-resolution of the processed video frames
* \returns 0 on failure or a pointer != 0 on success
*
* \see f0r_destruct
*/
f0r_instance_t f0r_construct(unsigned int width, unsigned int height);
/**
* Destroys an effect instance.
*
* \param instance The pointer to the plugins internal instance structure.
*
* \see f0r_construct
*/
void f0r_destruct(f0r_instance_t instance);
//---------------------------------------------------------------------------
/**
* Transparent parameter handle.
*/
typedef void* f0r_param_t;
/**
* This function allows the application to set the parameter values of an
* effect instance. Validity of the parameter pointer is handled by the
* application thus the data must be copied by the effect.
*
* Furthermore, if d an update event/signal is needed in a host
* application to notice when parameters have changed, this should be
* implemented inside its own update() call. The host application
* would presumably need to store the current value as well to see if
* it changes; to make this thread safe, it should store a copy of the
* current value in a struct which uses instance as a key.
*
* \param instance the effect instance
* \param param pointer to the parameter value
* \param param_index index of the parameter
*
* \see f0r_get_param_value
*/
void f0r_set_param_value(f0r_instance_t instance,
f0r_param_t param, int param_index);
/**
* This function allows the application to query the parameter values of an
* effect instance.
*
* \param instance the effect instance
* \param param pointer to the parameter value
* \param param_index index of the parameter
*
* \see f0r_set_param_value
*/
void f0r_get_param_value(f0r_instance_t instance,
f0r_param_t param, int param_index);
//---------------------------------------------------------------------------
/**
* This is where the core effect processing happens. The application calls it
* after it has set the necessary parameter values.
* inframe and outframe must be aligned to an integer multiple of 16 bytes
* in memory.
*
* This funcition should not alter the parameters of the effect in any
* way (\ref f0r_get_param_value should return the same values after a call
* to \ref f0r_update as before the call).
*
* The function is responsible to restore the fpu state (e.g. rounding mode)
* and mmx state if applicable before it returns to the caller.
*
* The host mustn't call \ref f0r_update for effects of type
* \ref F0R_PLUGIN_TYPE_MIXER2 and \ref F0R_PLUGIN_TYPE_MIXER3.
*
* \param instance the effect instance
* \param time the application time in seconds but with subsecond resolution
* (e.g. milli-second resolution). The resolution should be at least
* the inter-frame period of the application.
* \param inframe the incoming video frame (can be zero for sources)
* \param outframe the resulting video frame
*
* \see f0r_update2
*/
void f0r_update(f0r_instance_t instance,
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double time, const guint32* inframe, guint32* outframe);
//---------------------------------------------------------------------------
/**
* For effects of type \ref F0R_PLUGIN_TYPE_SOURCE or
* \ref F0R_PLUGIN_TYPE_FILTER this method is optional. The \ref f0r_update
* method must still be exported for these two effect types. If both are
* provided the behavior of them must be the same.
*
* Effects of type \ref F0R_PLUGIN_TYPE_MIXER2 or \ref F0R_PLUGIN_TYPE_MIXER3 must provide the new \ref f0r_update2 method.
* \param instance the effect instance
* \param time the application time in seconds but with subsecond resolution
* (e.g. milli-second resolution). The resolution should be at least
* the inter-frame period of the application.
* \param inframe1 the first incoming video frame (can be zero for sources)
* \param inframe2 the second incoming video frame
(can be zero for sources and filters)
* \param inframe3 the third incoming video frame
(can be zero for sources, filters and mixer2)
* \param outframe the resulting video frame
*
* \see f0r_update
*/
void f0r_update2(f0r_instance_t instance,
double time,
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const guint32* inframe1,
const guint32* inframe2,
const guint32* inframe3,
guint32* outframe);
//---------------------------------------------------------------------------
#endif