mirror of https://git.ffmpeg.org/ffmpeg.git
690 lines
26 KiB
C
690 lines
26 KiB
C
/*
|
|
* filter layer
|
|
* copyright (c) 2007 Bobby Bingham
|
|
*
|
|
* This file is part of FFmpeg.
|
|
*
|
|
* FFmpeg is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* FFmpeg 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
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with FFmpeg; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#ifndef AVFILTER_AVFILTER_H
|
|
#define AVFILTER_AVFILTER_H
|
|
|
|
#include "libavutil/avutil.h"
|
|
|
|
#define LIBAVFILTER_VERSION_MAJOR 1
|
|
#define LIBAVFILTER_VERSION_MINOR 15
|
|
#define LIBAVFILTER_VERSION_MICRO 0
|
|
|
|
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
|
|
LIBAVFILTER_VERSION_MINOR, \
|
|
LIBAVFILTER_VERSION_MICRO)
|
|
#define LIBAVFILTER_VERSION AV_VERSION(LIBAVFILTER_VERSION_MAJOR, \
|
|
LIBAVFILTER_VERSION_MINOR, \
|
|
LIBAVFILTER_VERSION_MICRO)
|
|
#define LIBAVFILTER_BUILD LIBAVFILTER_VERSION_INT
|
|
|
|
#include <stddef.h>
|
|
#include "libavcodec/avcodec.h"
|
|
|
|
/**
|
|
* Returns the LIBAVFILTER_VERSION_INT constant.
|
|
*/
|
|
unsigned avfilter_version(void);
|
|
|
|
/**
|
|
* Returns the libavfilter build-time configuration.
|
|
*/
|
|
const char *avfilter_configuration(void);
|
|
|
|
/**
|
|
* Returns the libavfilter license.
|
|
*/
|
|
const char *avfilter_license(void);
|
|
|
|
|
|
typedef struct AVFilterContext AVFilterContext;
|
|
typedef struct AVFilterLink AVFilterLink;
|
|
typedef struct AVFilterPad AVFilterPad;
|
|
|
|
/* TODO: look for other flags which may be useful in this structure (interlace
|
|
* flags, etc)
|
|
*/
|
|
/**
|
|
* A reference-counted picture data type used by the filter system. Filters
|
|
* should not store pointers to this structure directly, but instead use the
|
|
* AVFilterPicRef structure below.
|
|
*/
|
|
typedef struct AVFilterPic
|
|
{
|
|
uint8_t *data[4]; ///< picture data for each plane
|
|
int linesize[4]; ///< number of bytes per line
|
|
enum PixelFormat format; ///< colorspace
|
|
|
|
unsigned refcount; ///< number of references to this image
|
|
|
|
/** private data to be used by a custom free function */
|
|
void *priv;
|
|
/**
|
|
* A pointer to the function to deallocate this image if the default
|
|
* function is not sufficient. This could, for example, add the memory
|
|
* back into a memory pool to be reused later without the overhead of
|
|
* reallocating it from scratch.
|
|
*/
|
|
void (*free)(struct AVFilterPic *pic);
|
|
|
|
int w, h; ///< width and height of the allocated buffer
|
|
} AVFilterPic;
|
|
|
|
/**
|
|
* A reference to an AVFilterPic. Since filters can manipulate the origin of
|
|
* a picture to, for example, crop image without any memcpy, the picture origin
|
|
* and dimensions are per-reference properties. Linesize is also useful for
|
|
* image flipping, frame to field filters, etc, and so is also per-reference.
|
|
*
|
|
* TODO: add anything necessary for frame reordering
|
|
*/
|
|
typedef struct AVFilterPicRef
|
|
{
|
|
AVFilterPic *pic; ///< the picture that this is a reference to
|
|
uint8_t *data[4]; ///< picture data for each plane
|
|
int linesize[4]; ///< number of bytes per line
|
|
int w; ///< image width
|
|
int h; ///< image height
|
|
|
|
int64_t pts; ///< presentation timestamp in units of 1/AV_TIME_BASE
|
|
|
|
AVRational pixel_aspect; ///< pixel aspect ratio
|
|
|
|
int perms; ///< permissions
|
|
#define AV_PERM_READ 0x01 ///< can read from the buffer
|
|
#define AV_PERM_WRITE 0x02 ///< can write to the buffer
|
|
#define AV_PERM_PRESERVE 0x04 ///< nobody else can overwrite the buffer
|
|
#define AV_PERM_REUSE 0x08 ///< can output the buffer multiple times, with the same contents each time
|
|
#define AV_PERM_REUSE2 0x10 ///< can output the buffer multiple times, modified each time
|
|
} AVFilterPicRef;
|
|
|
|
/**
|
|
* Adds a new reference to a picture.
|
|
* @param ref an existing reference to the picture
|
|
* @param pmask a bitmask containing the allowable permissions in the new
|
|
* reference
|
|
* @return a new reference to the picture with the same properties as the
|
|
* old, excluding any permissions denied by pmask
|
|
*/
|
|
AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref, int pmask);
|
|
|
|
/**
|
|
* Removes a reference to a picture. If this is the last reference to the
|
|
* picture, the picture itself is also automatically freed.
|
|
* @param ref reference to the picture
|
|
*/
|
|
void avfilter_unref_pic(AVFilterPicRef *ref);
|
|
|
|
/**
|
|
* A list of supported formats for one end of a filter link. This is used
|
|
* during the format negotiation process to try to pick the best format to
|
|
* use to minimize the number of necessary conversions. Each filter gives a
|
|
* list of the formats supported by each input and output pad. The list
|
|
* given for each pad need not be distinct - they may be references to the
|
|
* same list of formats, as is often the case when a filter supports multiple
|
|
* formats, but will always output the same format as it is given in input.
|
|
*
|
|
* In this way, a list of possible input formats and a list of possible
|
|
* output formats are associated with each link. When a set of formats is
|
|
* negotiated over a link, the input and output lists are merged to form a
|
|
* new list containing only the common elements of each list. In the case
|
|
* that there were no common elements, a format conversion is necessary.
|
|
* Otherwise, the lists are merged, and all other links which reference
|
|
* either of the format lists involved in the merge are also affected.
|
|
*
|
|
* For example, consider the filter chain:
|
|
* filter (a) --> (b) filter (b) --> (c) filter
|
|
*
|
|
* where the letters in parenthesis indicate a list of formats supported on
|
|
* the input or output of the link. Suppose the lists are as follows:
|
|
* (a) = {A, B}
|
|
* (b) = {A, B, C}
|
|
* (c) = {B, C}
|
|
*
|
|
* First, the first link's lists are merged, yielding:
|
|
* filter (a) --> (a) filter (a) --> (c) filter
|
|
*
|
|
* Notice that format list (b) now refers to the same list as filter list (a).
|
|
* Next, the lists for the second link are merged, yielding:
|
|
* filter (a) --> (a) filter (a) --> (a) filter
|
|
*
|
|
* where (a) = {B}.
|
|
*
|
|
* Unfortunately, when the format lists at the two ends of a link are merged,
|
|
* we must ensure that all links which reference either pre-merge format list
|
|
* get updated as well. Therefore, we have the format list structure store a
|
|
* pointer to each of the pointers to itself.
|
|
*/
|
|
typedef struct AVFilterFormats AVFilterFormats;
|
|
struct AVFilterFormats
|
|
{
|
|
unsigned format_count; ///< number of formats
|
|
enum PixelFormat *formats; ///< list of pixel formats
|
|
|
|
unsigned refcount; ///< number of references to this list
|
|
AVFilterFormats ***refs; ///< references to this list
|
|
};
|
|
|
|
/**
|
|
* Creates a list of supported formats. This is intended for use in
|
|
* AVFilter->query_formats().
|
|
* @param pix_fmt list of pixel formats, terminated by PIX_FMT_NONE
|
|
* @return the format list, with no existing references
|
|
*/
|
|
AVFilterFormats *avfilter_make_format_list(const enum PixelFormat *pix_fmts);
|
|
|
|
/**
|
|
* Adds pix_fmt to the list of pixel formats contained in *avff.
|
|
* If *avff is NULL the function allocates the filter formats struct
|
|
* and puts its pointer in *avff.
|
|
*
|
|
* @return a non negative value in case of success, or a negative
|
|
* value corresponding to an AVERROR code in case of error
|
|
*/
|
|
int avfilter_add_colorspace(AVFilterFormats **avff, enum PixelFormat pix_fmt);
|
|
|
|
/**
|
|
* Returns a list of all colorspaces supported by FFmpeg.
|
|
*/
|
|
AVFilterFormats *avfilter_all_colorspaces(void);
|
|
|
|
/**
|
|
* Returns a format list which contains the intersection of the formats of
|
|
* a and b. Also, all the references of a, all the references of b, and
|
|
* a and b themselves will be deallocated.
|
|
*
|
|
* If a and b do not share any common formats, neither is modified, and NULL
|
|
* is returned.
|
|
*/
|
|
AVFilterFormats *avfilter_merge_formats(AVFilterFormats *a, AVFilterFormats *b);
|
|
|
|
/**
|
|
* Adds *ref as a new reference to formats.
|
|
* That is the pointers will point like in the ascii art below:
|
|
* ________
|
|
* |formats |<--------.
|
|
* | ____ | ____|___________________
|
|
* | |refs| | | __|_
|
|
* | |* * | | | | | | AVFilterLink
|
|
* | |* *--------->|*ref|
|
|
* | |____| | | |____|
|
|
* |________| |________________________
|
|
*/
|
|
void avfilter_formats_ref(AVFilterFormats *formats, AVFilterFormats **ref);
|
|
|
|
/**
|
|
* If *ref is non-NULL, removes *ref as a reference to the format list
|
|
* it currently points to, deallocates that list if this was the last
|
|
* reference, and sets *ref to NULL.
|
|
*
|
|
* Before After
|
|
* ________ ________ NULL
|
|
* |formats |<--------. |formats | ^
|
|
* | ____ | ____|________________ | ____ | ____|________________
|
|
* | |refs| | | __|_ | |refs| | | __|_
|
|
* | |* * | | | | | | AVFilterLink | |* * | | | | | | AVFilterLink
|
|
* | |* *--------->|*ref| | |* | | | |*ref|
|
|
* | |____| | | |____| | |____| | | |____|
|
|
* |________| |_____________________ |________| |_____________________
|
|
*/
|
|
void avfilter_formats_unref(AVFilterFormats **ref);
|
|
|
|
/**
|
|
*
|
|
* Before After
|
|
* ________ ________
|
|
* |formats |<---------. |formats |<---------.
|
|
* | ____ | ___|___ | ____ | ___|___
|
|
* | |refs| | | | | | |refs| | | | | NULL
|
|
* | |* *--------->|*oldref| | |* *--------->|*newref| ^
|
|
* | |* * | | |_______| | |* * | | |_______| ___|___
|
|
* | |____| | | |____| | | | |
|
|
* |________| |________| |*oldref|
|
|
* |_______|
|
|
*/
|
|
void avfilter_formats_changeref(AVFilterFormats **oldref,
|
|
AVFilterFormats **newref);
|
|
|
|
/**
|
|
* A filter pad used for either input or output.
|
|
*/
|
|
struct AVFilterPad
|
|
{
|
|
/**
|
|
* Pad name. The name is unique among inputs and among outputs, but an
|
|
* input may have the same name as an output. This may be NULL if this
|
|
* pad has no need to ever be referenced by name.
|
|
*/
|
|
const char *name;
|
|
|
|
/**
|
|
* AVFilterPad type. Only video supported now, hopefully someone will
|
|
* add audio in the future.
|
|
*/
|
|
enum CodecType type;
|
|
|
|
/**
|
|
* Minimum required permissions on incoming buffers. Any buffer with
|
|
* insufficient permissions will be automatically copied by the filter
|
|
* system to a new buffer which provides the needed access permissions.
|
|
*
|
|
* Input pads only.
|
|
*/
|
|
int min_perms;
|
|
|
|
/**
|
|
* Permissions which are not accepted on incoming buffers. Any buffer
|
|
* which has any of these permissions set will be automatically copied
|
|
* by the filter system to a new buffer which does not have those
|
|
* permissions. This can be used to easily disallow buffers with
|
|
* AV_PERM_REUSE.
|
|
*
|
|
* Input pads only.
|
|
*/
|
|
int rej_perms;
|
|
|
|
/**
|
|
* Callback called before passing the first slice of a new frame. If
|
|
* NULL, the filter layer will default to storing a reference to the
|
|
* picture inside the link structure.
|
|
*
|
|
* Input video pads only.
|
|
*/
|
|
void (*start_frame)(AVFilterLink *link, AVFilterPicRef *picref);
|
|
|
|
/**
|
|
* Callback function to get a buffer. If NULL, the filter system will
|
|
* use avfilter_default_get_video_buffer().
|
|
*
|
|
* Input video pads only.
|
|
*/
|
|
AVFilterPicRef *(*get_video_buffer)(AVFilterLink *link, int perms, int w, int h);
|
|
|
|
/**
|
|
* Callback called after the slices of a frame are completely sent. If
|
|
* NULL, the filter layer will default to releasing the reference stored
|
|
* in the link structure during start_frame().
|
|
*
|
|
* Input video pads only.
|
|
*/
|
|
void (*end_frame)(AVFilterLink *link);
|
|
|
|
/**
|
|
* Slice drawing callback. This is where a filter receives video data
|
|
* and should do its processing.
|
|
*
|
|
* Input video pads only.
|
|
*/
|
|
void (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir);
|
|
|
|
/**
|
|
* Frame poll callback. This returns the number of immediately available
|
|
* frames. It should return a positive value if the next request_frame()
|
|
* is guaranteed to return one frame (with no delay).
|
|
*
|
|
* Defaults to just calling the source poll_frame() method.
|
|
*
|
|
* Output video pads only.
|
|
*/
|
|
int (*poll_frame)(AVFilterLink *link);
|
|
|
|
/**
|
|
* Frame request callback. A call to this should result in at least one
|
|
* frame being output over the given link. This should return zero on
|
|
* success, and another value on error.
|
|
*
|
|
* Output video pads only.
|
|
*/
|
|
int (*request_frame)(AVFilterLink *link);
|
|
|
|
/**
|
|
* Link configuration callback.
|
|
*
|
|
* For output pads, this should set the link properties such as
|
|
* width/height. This should NOT set the format property - that is
|
|
* negotiated between filters by the filter system using the
|
|
* query_formats() callback before this function is called.
|
|
*
|
|
* For input pads, this should check the properties of the link, and update
|
|
* the filter's internal state as necessary.
|
|
*
|
|
* For both input and output filters, this should return zero on success,
|
|
* and another value on error.
|
|
*/
|
|
int (*config_props)(AVFilterLink *link);
|
|
};
|
|
|
|
/** default handler for start_frame() for video inputs */
|
|
void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
|
|
/** default handler for draw_slice() for video inputs */
|
|
void avfilter_default_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);
|
|
/** default handler for end_frame() for video inputs */
|
|
void avfilter_default_end_frame(AVFilterLink *link);
|
|
/** default handler for config_props() for video outputs */
|
|
int avfilter_default_config_output_link(AVFilterLink *link);
|
|
/** default handler for config_props() for video inputs */
|
|
int avfilter_default_config_input_link (AVFilterLink *link);
|
|
/** default handler for get_video_buffer() for video inputs */
|
|
AVFilterPicRef *avfilter_default_get_video_buffer(AVFilterLink *link,
|
|
int perms, int w, int h);
|
|
/**
|
|
* A helper for query_formats() which sets all links to the same list of
|
|
* formats. If there are no links hooked to this filter, the list of formats is
|
|
* freed.
|
|
*/
|
|
void avfilter_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats);
|
|
/** Default handler for query_formats() */
|
|
int avfilter_default_query_formats(AVFilterContext *ctx);
|
|
|
|
/**
|
|
* Filter definition. This defines the pads a filter contains, and all the
|
|
* callback functions used to interact with the filter.
|
|
*/
|
|
typedef struct AVFilter
|
|
{
|
|
const char *name; ///< filter name
|
|
|
|
int priv_size; ///< size of private data to allocate for the filter
|
|
|
|
/**
|
|
* Filter initialization function. Args contains the user-supplied
|
|
* parameters. FIXME: maybe an AVOption-based system would be better?
|
|
* opaque is data provided by the code requesting creation of the filter,
|
|
* and is used to pass data to the filter.
|
|
*/
|
|
int (*init)(AVFilterContext *ctx, const char *args, void *opaque);
|
|
|
|
/**
|
|
* Filter uninitialization function. Should deallocate any memory held
|
|
* by the filter, release any picture references, etc. This does not need
|
|
* to deallocate the AVFilterContext->priv memory itself.
|
|
*/
|
|
void (*uninit)(AVFilterContext *ctx);
|
|
|
|
/**
|
|
* Queries formats supported by the filter and its pads, and sets the
|
|
* in_formats for links connected to its output pads, and out_formats
|
|
* for links connected to its input pads.
|
|
*
|
|
* @return zero on success, a negative value corresponding to an
|
|
* AVERROR code otherwise
|
|
*/
|
|
int (*query_formats)(AVFilterContext *);
|
|
|
|
const AVFilterPad *inputs; ///< NULL terminated list of inputs. NULL if none
|
|
const AVFilterPad *outputs; ///< NULL terminated list of outputs. NULL if none
|
|
|
|
/**
|
|
* A description for the filter. You should use the
|
|
* NULL_IF_CONFIG_SMALL() macro to define it.
|
|
*/
|
|
const char *description;
|
|
} AVFilter;
|
|
|
|
/** An instance of a filter */
|
|
struct AVFilterContext
|
|
{
|
|
const AVClass *av_class; ///< needed for av_log()
|
|
|
|
AVFilter *filter; ///< the AVFilter of which this is an instance
|
|
|
|
char *name; ///< name of this filter instance
|
|
|
|
unsigned input_count; ///< number of input pads
|
|
AVFilterPad *input_pads; ///< array of input pads
|
|
AVFilterLink **inputs; ///< array of pointers to input links
|
|
|
|
unsigned output_count; ///< number of output pads
|
|
AVFilterPad *output_pads; ///< array of output pads
|
|
AVFilterLink **outputs; ///< array of pointers to output links
|
|
|
|
void *priv; ///< private data for use by the filter
|
|
};
|
|
|
|
/**
|
|
* A link between two filters. This contains pointers to the source and
|
|
* destination filters between which this link exists, and the indexes of
|
|
* the pads involved. In addition, this link also contains the parameters
|
|
* which have been negotiated and agreed upon between the filter, such as
|
|
* image dimensions, format, etc.
|
|
*/
|
|
struct AVFilterLink
|
|
{
|
|
AVFilterContext *src; ///< source filter
|
|
unsigned int srcpad; ///< index of the output pad on the source filter
|
|
|
|
AVFilterContext *dst; ///< dest filter
|
|
unsigned int dstpad; ///< index of the input pad on the dest filter
|
|
|
|
/** stage of the initialization of the link properties (dimensions, etc) */
|
|
enum {
|
|
AVLINK_UNINIT = 0, ///< not started
|
|
AVLINK_STARTINIT, ///< started, but incomplete
|
|
AVLINK_INIT ///< complete
|
|
} init_state;
|
|
|
|
int w; ///< agreed upon image width
|
|
int h; ///< agreed upon image height
|
|
enum PixelFormat format; ///< agreed upon image colorspace
|
|
|
|
/**
|
|
* Lists of formats supported by the input and output filters respectively.
|
|
* These lists are used for negotiating the format to actually be used,
|
|
* which will be loaded into the format member, above, when chosen.
|
|
*/
|
|
AVFilterFormats *in_formats;
|
|
AVFilterFormats *out_formats;
|
|
|
|
/**
|
|
* The picture reference currently being sent across the link by the source
|
|
* filter. This is used internally by the filter system to allow
|
|
* automatic copying of pictures which do not have sufficient permissions
|
|
* for the destination. This should not be accessed directly by the
|
|
* filters.
|
|
*/
|
|
AVFilterPicRef *srcpic;
|
|
|
|
AVFilterPicRef *cur_pic;
|
|
AVFilterPicRef *outpic;
|
|
};
|
|
|
|
/**
|
|
* Links two filters together.
|
|
* @param src the source filter
|
|
* @param srcpad index of the output pad on the source filter
|
|
* @param dst the destination filter
|
|
* @param dstpad index of the input pad on the destination filter
|
|
* @return zero on success
|
|
*/
|
|
int avfilter_link(AVFilterContext *src, unsigned srcpad,
|
|
AVFilterContext *dst, unsigned dstpad);
|
|
|
|
/**
|
|
* Negotiates the colorspace, dimensions, etc of all inputs to a filter.
|
|
* @param filter the filter to negotiate the properties for its inputs
|
|
* @return zero on successful negotiation
|
|
*/
|
|
int avfilter_config_links(AVFilterContext *filter);
|
|
|
|
/**
|
|
* Requests a picture buffer with a specific set of permissions.
|
|
* @param link the output link to the filter from which the picture will
|
|
* be requested
|
|
* @param perms the required access permissions
|
|
* @param w the minimum width of the buffer to allocate
|
|
* @param h the minimum height of the buffer to allocate
|
|
* @return A reference to the picture. This must be unreferenced with
|
|
* avfilter_unref_pic when you are finished with it.
|
|
*/
|
|
AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms,
|
|
int w, int h);
|
|
|
|
/**
|
|
* Requests an input frame from the filter at the other end of the link.
|
|
* @param link the input link
|
|
* @return zero on success
|
|
*/
|
|
int avfilter_request_frame(AVFilterLink *link);
|
|
|
|
/**
|
|
* Polls a frame from the filter chain.
|
|
* @param link the input link
|
|
* @return the number of immediately available frames, a negative
|
|
* number in case of error
|
|
*/
|
|
int avfilter_poll_frame(AVFilterLink *link);
|
|
|
|
/**
|
|
* Notifies the next filter of the start of a frame.
|
|
* @param link the output link the frame will be sent over
|
|
* @param picref A reference to the frame about to be sent. The data for this
|
|
* frame need only be valid once draw_slice() is called for that
|
|
* portion. The receiving filter will free this reference when
|
|
* it no longer needs it.
|
|
*/
|
|
void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
|
|
|
|
/**
|
|
* Notifies the next filter that the current frame has finished.
|
|
* @param link the output link the frame was sent over
|
|
*/
|
|
void avfilter_end_frame(AVFilterLink *link);
|
|
|
|
/**
|
|
* Sends a slice to the next filter.
|
|
*
|
|
* Slices have to be provided in sequential order, either in
|
|
* top-bottom or bottom-top order. If slices are provided in
|
|
* non-sequential order the behavior of the function is undefined.
|
|
*
|
|
* @param link the output link over which the frame is being sent
|
|
* @param y offset in pixels from the top of the image for this slice
|
|
* @param h height of this slice in pixels
|
|
* @param slice_dir the assumed direction for sending slices,
|
|
* from the top slice to the bottom slice if the value is 1,
|
|
* from the bottom slice to the top slice if the value is -1,
|
|
* for other values the behavior of the function is undefined.
|
|
*/
|
|
void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);
|
|
|
|
/** Initializes the filter system. Registers all builtin filters. */
|
|
void avfilter_register_all(void);
|
|
|
|
/** Uninitializes the filter system. Unregisters all filters. */
|
|
void avfilter_uninit(void);
|
|
|
|
/**
|
|
* Registers a filter. This is only needed if you plan to use
|
|
* avfilter_get_by_name later to lookup the AVFilter structure by name. A
|
|
* filter can still by instantiated with avfilter_open even if it is not
|
|
* registered.
|
|
* @param filter the filter to register
|
|
* @return 0 if the registration was succesfull, a negative value
|
|
* otherwise
|
|
*/
|
|
int avfilter_register(AVFilter *filter);
|
|
|
|
/**
|
|
* Gets a filter definition matching the given name.
|
|
* @param name the filter name to find
|
|
* @return the filter definition, if any matching one is registered.
|
|
* NULL if none found.
|
|
*/
|
|
AVFilter *avfilter_get_by_name(const char *name);
|
|
|
|
/**
|
|
* If filter is NULL, returns a pointer to the first registered filter pointer,
|
|
* if filter is non-NULL, returns the next pointer after filter.
|
|
* If the returned pointer points to NULL, the last registered filter
|
|
* was already reached.
|
|
*/
|
|
AVFilter **av_filter_next(AVFilter **filter);
|
|
|
|
/**
|
|
* Creates a filter instance.
|
|
* @param filter the filter to create an instance of
|
|
* @param inst_name Name to give to the new instance. Can be NULL for none.
|
|
* @return Pointer to the new instance on success. NULL on failure.
|
|
*/
|
|
AVFilterContext *avfilter_open(AVFilter *filter, const char *inst_name);
|
|
|
|
/**
|
|
* Initializes a filter.
|
|
* @param filter the filter to initialize
|
|
* @param args A string of parameters to use when initializing the filter.
|
|
* The format and meaning of this string varies by filter.
|
|
* @param opaque Any extra non-string data needed by the filter. The meaning
|
|
* of this parameter varies by filter.
|
|
* @return zero on success
|
|
*/
|
|
int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque);
|
|
|
|
/**
|
|
* Destroys a filter.
|
|
* @param filter the filter to destroy
|
|
*/
|
|
void avfilter_destroy(AVFilterContext *filter);
|
|
|
|
/**
|
|
* Inserts a filter in the middle of an existing link.
|
|
* @param link the link into which the filter should be inserted
|
|
* @param filt the filter to be inserted
|
|
* @param in the input pad on the filter to connect
|
|
* @param out the output pad on the filter to connect
|
|
* @return zero on success
|
|
*/
|
|
int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
|
|
unsigned in, unsigned out);
|
|
|
|
/**
|
|
* Inserts a new pad.
|
|
* @param idx Insertion point. Pad is inserted at the end if this point
|
|
* is beyond the end of the list of pads.
|
|
* @param count Pointer to the number of pads in the list
|
|
* @param padidx_off Offset within an AVFilterLink structure to the element
|
|
* to increment when inserting a new pad causes link
|
|
* numbering to change
|
|
* @param pads Pointer to the pointer to the beginning of the list of pads
|
|
* @param links Pointer to the pointer to the beginning of the list of links
|
|
* @param newpad The new pad to add. A copy is made when adding.
|
|
*/
|
|
void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
|
|
AVFilterPad **pads, AVFilterLink ***links,
|
|
AVFilterPad *newpad);
|
|
|
|
/** Inserts a new input pad for the filter. */
|
|
static inline void avfilter_insert_inpad(AVFilterContext *f, unsigned index,
|
|
AVFilterPad *p)
|
|
{
|
|
avfilter_insert_pad(index, &f->input_count, offsetof(AVFilterLink, dstpad),
|
|
&f->input_pads, &f->inputs, p);
|
|
}
|
|
|
|
/** Inserts a new output pad for the filter. */
|
|
static inline void avfilter_insert_outpad(AVFilterContext *f, unsigned index,
|
|
AVFilterPad *p)
|
|
{
|
|
avfilter_insert_pad(index, &f->output_count, offsetof(AVFilterLink, srcpad),
|
|
&f->output_pads, &f->outputs, p);
|
|
}
|
|
|
|
#endif /* AVFILTER_AVFILTER_H */
|