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/*
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 * filter layer
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 * copyright (c) 2007 Bobby Bingham
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef AVFILTER_AVFILTER_H
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#define AVFILTER_AVFILTER_H
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#include "libavutil/avutil.h"
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#define LIBAVFILTER_VERSION_MAJOR  1
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#define LIBAVFILTER_VERSION_MINOR 18
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#define LIBAVFILTER_VERSION_MICRO  0
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#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
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                                               LIBAVFILTER_VERSION_MINOR, \
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                                               LIBAVFILTER_VERSION_MICRO)
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#define LIBAVFILTER_VERSION     AV_VERSION(LIBAVFILTER_VERSION_MAJOR,   \
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                                           LIBAVFILTER_VERSION_MINOR,   \
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                                           LIBAVFILTER_VERSION_MICRO)
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#define LIBAVFILTER_BUILD       LIBAVFILTER_VERSION_INT
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#include <stddef.h>
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#include "libavcodec/avcodec.h"
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/**
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 * Returns the LIBAVFILTER_VERSION_INT constant.
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 */
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unsigned avfilter_version(void);
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/**
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 * Returns the libavfilter build-time configuration.
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 */
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const char *avfilter_configuration(void);
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/**
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 * Returns the libavfilter license.
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 */
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const char *avfilter_license(void);
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typedef struct AVFilterContext AVFilterContext;
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typedef struct AVFilterLink    AVFilterLink;
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typedef struct AVFilterPad     AVFilterPad;
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/* TODO: look for other flags which may be useful in this structure (interlace
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 * flags, etc)
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 */
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/**
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 * A reference-counted picture data type used by the filter system. Filters
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 * should not store pointers to this structure directly, but instead use the
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 * AVFilterPicRef structure below.
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 */
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typedef struct AVFilterPic
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{
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    uint8_t *data[4];           ///< picture data for each plane
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    int linesize[4];            ///< number of bytes per line
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    enum PixelFormat format;    ///< colorspace
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    unsigned refcount;          ///< number of references to this image
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    /** private data to be used by a custom free function */
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    void *priv;
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    /**
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     * A pointer to the function to deallocate this image if the default
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     * function is not sufficient. This could, for example, add the memory
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     * back into a memory pool to be reused later without the overhead of
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     * reallocating it from scratch.
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     */
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    void (*free)(struct AVFilterPic *pic);
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    int w, h;                  ///< width and height of the allocated buffer
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} AVFilterPic;
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/**
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 * A reference to an AVFilterPic. Since filters can manipulate the origin of
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 * a picture to, for example, crop image without any memcpy, the picture origin
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 * and dimensions are per-reference properties. Linesize is also useful for
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 * image flipping, frame to field filters, etc, and so is also per-reference.
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 *
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 * TODO: add anything necessary for frame reordering
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 */
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typedef struct AVFilterPicRef
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{
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    AVFilterPic *pic;           ///< the picture that this is a reference to
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    uint8_t *data[4];           ///< picture data for each plane
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    int linesize[4];            ///< number of bytes per line
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    int w;                      ///< image width
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    int h;                      ///< image height
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    int64_t pts;                ///< presentation timestamp in units of 1/AV_TIME_BASE
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    int64_t pos;                ///< byte position in stream, -1 if unknown
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    AVRational pixel_aspect;    ///< pixel aspect ratio
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    int perms;                  ///< permissions
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#define AV_PERM_READ     0x01   ///< can read from the buffer
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#define AV_PERM_WRITE    0x02   ///< can write to the buffer
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#define AV_PERM_PRESERVE 0x04   ///< nobody else can overwrite the buffer
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#define AV_PERM_REUSE    0x08   ///< can output the buffer multiple times, with the same contents each time
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#define AV_PERM_REUSE2   0x10   ///< can output the buffer multiple times, modified each time
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} AVFilterPicRef;
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/**
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 * Adds a new reference to a picture.
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 * @param ref   an existing reference to the picture
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 * @param pmask a bitmask containing the allowable permissions in the new
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 *              reference
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 * @return      a new reference to the picture with the same properties as the
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 *              old, excluding any permissions denied by pmask
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 */
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AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref, int pmask);
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/**
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 * Removes a reference to a picture. If this is the last reference to the
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 * picture, the picture itself is also automatically freed.
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 * @param ref reference to the picture
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 */
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void avfilter_unref_pic(AVFilterPicRef *ref);
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/**
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 * A list of supported formats for one end of a filter link. This is used
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 * during the format negotiation process to try to pick the best format to
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 * use to minimize the number of necessary conversions. Each filter gives a
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 * list of the formats supported by each input and output pad. The list
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 * given for each pad need not be distinct - they may be references to the
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 * same list of formats, as is often the case when a filter supports multiple
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 * formats, but will always output the same format as it is given in input.
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 *
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 * In this way, a list of possible input formats and a list of possible
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 * output formats are associated with each link. When a set of formats is
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 * negotiated over a link, the input and output lists are merged to form a
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 * new list containing only the common elements of each list. In the case
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 * that there were no common elements, a format conversion is necessary.
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 * Otherwise, the lists are merged, and all other links which reference
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 * either of the format lists involved in the merge are also affected.
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 *
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 * For example, consider the filter chain:
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 * filter (a) --> (b) filter (b) --> (c) filter
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 *
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 * where the letters in parenthesis indicate a list of formats supported on
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 * the input or output of the link. Suppose the lists are as follows:
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 * (a) = {A, B}
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 * (b) = {A, B, C}
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 * (c) = {B, C}
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 *
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 * First, the first link's lists are merged, yielding:
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 * filter (a) --> (a) filter (a) --> (c) filter
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 *
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 * Notice that format list (b) now refers to the same list as filter list (a).
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 * Next, the lists for the second link are merged, yielding:
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 * filter (a) --> (a) filter (a) --> (a) filter
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 *
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 * where (a) = {B}.
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 *
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 * Unfortunately, when the format lists at the two ends of a link are merged,
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 * we must ensure that all links which reference either pre-merge format list
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 * get updated as well. Therefore, we have the format list structure store a
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 * pointer to each of the pointers to itself.
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 */
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typedef struct AVFilterFormats AVFilterFormats;
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struct AVFilterFormats
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{
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    unsigned format_count;      ///< number of formats
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    enum PixelFormat *formats;  ///< list of pixel formats
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    unsigned refcount;          ///< number of references to this list
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    AVFilterFormats ***refs;    ///< references to this list
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};
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/**
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 * Creates a list of supported formats. This is intended for use in
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 * AVFilter->query_formats().
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 * @param pix_fmt list of pixel formats, terminated by PIX_FMT_NONE
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 * @return the format list, with no existing references
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 */
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AVFilterFormats *avfilter_make_format_list(const enum PixelFormat *pix_fmts);
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/**
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 * Adds pix_fmt to the list of pixel formats contained in *avff.
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 * If *avff is NULL the function allocates the filter formats struct
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 * and puts its pointer in *avff.
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 *
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 * @return a non negative value in case of success, or a negative
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 * value corresponding to an AVERROR code in case of error
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 */
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int avfilter_add_colorspace(AVFilterFormats **avff, enum PixelFormat pix_fmt);
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/**
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 * Returns a list of all colorspaces supported by FFmpeg.
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 */
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AVFilterFormats *avfilter_all_colorspaces(void);
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/**
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 * Returns a format list which contains the intersection of the formats of
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 * a and b. Also, all the references of a, all the references of b, and
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 * a and b themselves will be deallocated.
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 *
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 * If a and b do not share any common formats, neither is modified, and NULL
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 * is returned.
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 */
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AVFilterFormats *avfilter_merge_formats(AVFilterFormats *a, AVFilterFormats *b);
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/**
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 * Adds *ref as a new reference to formats.
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 * That is the pointers will point like in the ascii art below:
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 *   ________
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 *  |formats |<--------.
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 *  |  ____  |     ____|___________________
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 *  | |refs| |    |  __|_
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 *  | |* * | |    | |  | |  AVFilterLink
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 *  | |* *--------->|*ref|
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 *  | |____| |    | |____|
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 *  |________|    |________________________
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 */
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void avfilter_formats_ref(AVFilterFormats *formats, AVFilterFormats **ref);
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/**
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 * If *ref is non-NULL, removes *ref as a reference to the format list
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 * it currently points to, deallocates that list if this was the last
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 * reference, and sets *ref to NULL.
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 *
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 *         Before                                 After
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 *   ________                               ________         NULL
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 *  |formats |<--------.                   |formats |         ^
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 *  |  ____  |     ____|________________   |  ____  |     ____|________________
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 *  | |refs| |    |  __|_                  | |refs| |    |  __|_
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 *  | |* * | |    | |  | |  AVFilterLink   | |* * | |    | |  | |  AVFilterLink
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 *  | |* *--------->|*ref|                 | |*   | |    | |*ref|
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 *  | |____| |    | |____|                 | |____| |    | |____|
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 *  |________|    |_____________________   |________|    |_____________________
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 */
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void avfilter_formats_unref(AVFilterFormats **ref);
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/**
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 *
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 *         Before                                 After
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 *   ________                         ________
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 *  |formats |<---------.            |formats |<---------.
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 *  |  ____  |       ___|___         |  ____  |       ___|___
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 *  | |refs| |      |   |   |        | |refs| |      |   |   |   NULL
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 *  | |* *--------->|*oldref|        | |* *--------->|*newref|     ^
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 *  | |* * | |      |_______|        | |* * | |      |_______|  ___|___
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 *  | |____| |                       | |____| |                |   |   |
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 *  |________|                       |________|                |*oldref|
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 *                                                             |_______|
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 */
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void avfilter_formats_changeref(AVFilterFormats **oldref,
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                                AVFilterFormats **newref);
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/**
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 * A filter pad used for either input or output.
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 */
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struct AVFilterPad
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{
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    /**
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     * Pad name. The name is unique among inputs and among outputs, but an
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     * input may have the same name as an output. This may be NULL if this
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     * pad has no need to ever be referenced by name.
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     */
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    const char *name;
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    /**
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     * AVFilterPad type. Only video supported now, hopefully someone will
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     * add audio in the future.
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     */
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    enum CodecType type;
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    /**
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     * Minimum required permissions on incoming buffers. Any buffer with
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     * insufficient permissions will be automatically copied by the filter
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     * system to a new buffer which provides the needed access permissions.
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     *
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     * Input pads only.
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     */
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    int min_perms;
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    /**
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     * Permissions which are not accepted on incoming buffers. Any buffer
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     * which has any of these permissions set will be automatically copied
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     * by the filter system to a new buffer which does not have those
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     * permissions. This can be used to easily disallow buffers with
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     * AV_PERM_REUSE.
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     *
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     * Input pads only.
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     */
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    int rej_perms;
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    /**
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     * Callback called before passing the first slice of a new frame. If
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     * NULL, the filter layer will default to storing a reference to the
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     * picture inside the link structure.
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     *
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     * Input video pads only.
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     */
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    void (*start_frame)(AVFilterLink *link, AVFilterPicRef *picref);
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    /**
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     * Callback function to get a buffer. If NULL, the filter system will
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     * use avfilter_default_get_video_buffer().
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     *
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     * Input video pads only.
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     */
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    AVFilterPicRef *(*get_video_buffer)(AVFilterLink *link, int perms, int w, int h);
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    /**
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     * Callback called after the slices of a frame are completely sent. If
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     * NULL, the filter layer will default to releasing the reference stored
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     * in the link structure during start_frame().
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     *
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     * Input video pads only.
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     */
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    void (*end_frame)(AVFilterLink *link);
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    /**
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     * Slice drawing callback. This is where a filter receives video data
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     * and should do its processing.
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     *
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     * Input video pads only.
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     */
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    void (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir);
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    /**
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     * Frame poll callback. This returns the number of immediately available
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     * frames. It should return a positive value if the next request_frame()
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     * is guaranteed to return one frame (with no delay).
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     *
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     * Defaults to just calling the source poll_frame() method.
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     *
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     * Output video pads only.
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     */
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    int (*poll_frame)(AVFilterLink *link);
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    /**
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     * Frame request callback. A call to this should result in at least one
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     * frame being output over the given link. This should return zero on
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     * success, and another value on error.
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     *
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     * Output video pads only.
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     */
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    int (*request_frame)(AVFilterLink *link);
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    /**
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     * Link configuration callback.
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     *
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     * For output pads, this should set the link properties such as
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     * width/height. This should NOT set the format property - that is
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     * negotiated between filters by the filter system using the
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     * query_formats() callback before this function is called.
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     *
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     * For input pads, this should check the properties of the link, and update
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     * the filter's internal state as necessary.
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     *
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     * For both input and output filters, this should return zero on success,
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     * and another value on error.
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     */
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    int (*config_props)(AVFilterLink *link);
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};
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/** default handler for start_frame() for video inputs */
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void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
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/** default handler for draw_slice() for video inputs */
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void avfilter_default_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);
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/** default handler for end_frame() for video inputs */
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void avfilter_default_end_frame(AVFilterLink *link);
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/** default handler for config_props() for video outputs */
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int avfilter_default_config_output_link(AVFilterLink *link);
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/** default handler for config_props() for video inputs */
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int avfilter_default_config_input_link (AVFilterLink *link);
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/** default handler for get_video_buffer() for video inputs */
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AVFilterPicRef *avfilter_default_get_video_buffer(AVFilterLink *link,
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                                                  int perms, int w, int h);
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/**
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 * A helper for query_formats() which sets all links to the same list of
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 * formats. If there are no links hooked to this filter, the list of formats is
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 * freed.
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 */
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void avfilter_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats);
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/** Default handler for query_formats() */
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int avfilter_default_query_formats(AVFilterContext *ctx);
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/** start_frame() handler for filters which simply pass video along */
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void avfilter_null_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
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/** draw_slice() handler for filters which simply pass video along */
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void avfilter_null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);
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/** end_frame() handler for filters which simply pass video along */
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void avfilter_null_end_frame(AVFilterLink *link);
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/** get_video_buffer() handler for filters which simply pass video along */
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AVFilterPicRef *avfilter_null_get_video_buffer(AVFilterLink *link,
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                                                  int perms, int w, int h);
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/**
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 * Filter definition. This defines the pads a filter contains, and all the
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 * callback functions used to interact with the filter.
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 */
415
typedef struct AVFilter
416
{
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    const char *name;         ///< filter name
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    int priv_size;      ///< size of private data to allocate for the filter
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    /**
422
     * Filter initialization function. Args contains the user-supplied
423
     * parameters. FIXME: maybe an AVOption-based system would be better?
424
     * opaque is data provided by the code requesting creation of the filter,
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     * and is used to pass data to the filter.
426
     */
427
    int (*init)(AVFilterContext *ctx, const char *args, void *opaque);
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    /**
430
     * Filter uninitialization function. Should deallocate any memory held
431
     * by the filter, release any picture references, etc. This does not need
432
     * to deallocate the AVFilterContext->priv memory itself.
433
     */
434
    void (*uninit)(AVFilterContext *ctx);
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    /**
437
     * Queries formats supported by the filter and its pads, and sets the
438
     * in_formats for links connected to its output pads, and out_formats
439
     * for links connected to its input pads.
440
     *
441
     * @return zero on success, a negative value corresponding to an
442
     * AVERROR code otherwise
443
     */
444
    int (*query_formats)(AVFilterContext *);
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446
    const AVFilterPad *inputs;  ///< NULL terminated list of inputs. NULL if none
447
    const AVFilterPad *outputs; ///< NULL terminated list of outputs. NULL if none
448

    
449
    /**
450
     * A description for the filter. You should use the
451
     * NULL_IF_CONFIG_SMALL() macro to define it.
452
     */
453
    const char *description;
454
} AVFilter;
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456
/** An instance of a filter */
457
struct AVFilterContext
458
{
459
    const AVClass *av_class;              ///< needed for av_log()
460

    
461
    AVFilter *filter;               ///< the AVFilter of which this is an instance
462

    
463
    char *name;                     ///< name of this filter instance
464

    
465
    unsigned input_count;           ///< number of input pads
466
    AVFilterPad   *input_pads;      ///< array of input pads
467
    AVFilterLink **inputs;          ///< array of pointers to input links
468

    
469
    unsigned output_count;          ///< number of output pads
470
    AVFilterPad   *output_pads;     ///< array of output pads
471
    AVFilterLink **outputs;         ///< array of pointers to output links
472

    
473
    void *priv;                     ///< private data for use by the filter
474
};
475

    
476
/**
477
 * A link between two filters. This contains pointers to the source and
478
 * destination filters between which this link exists, and the indexes of
479
 * the pads involved. In addition, this link also contains the parameters
480
 * which have been negotiated and agreed upon between the filter, such as
481
 * image dimensions, format, etc.
482
 */
483
struct AVFilterLink
484
{
485
    AVFilterContext *src;       ///< source filter
486
    unsigned int srcpad;        ///< index of the output pad on the source filter
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488
    AVFilterContext *dst;       ///< dest filter
489
    unsigned int dstpad;        ///< index of the input pad on the dest filter
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491
    /** stage of the initialization of the link properties (dimensions, etc) */
492
    enum {
493
        AVLINK_UNINIT = 0,      ///< not started
494
        AVLINK_STARTINIT,       ///< started, but incomplete
495
        AVLINK_INIT             ///< complete
496
    } init_state;
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498
    int w;                      ///< agreed upon image width
499
    int h;                      ///< agreed upon image height
500
    enum PixelFormat format;    ///< agreed upon image colorspace
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502
    /**
503
     * Lists of formats supported by the input and output filters respectively.
504
     * These lists are used for negotiating the format to actually be used,
505
     * which will be loaded into the format member, above, when chosen.
506
     */
507
    AVFilterFormats *in_formats;
508
    AVFilterFormats *out_formats;
509

    
510
    /**
511
     * The picture reference currently being sent across the link by the source
512
     * filter. This is used internally by the filter system to allow
513
     * automatic copying of pictures which do not have sufficient permissions
514
     * for the destination. This should not be accessed directly by the
515
     * filters.
516
     */
517
    AVFilterPicRef *srcpic;
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519
    AVFilterPicRef *cur_pic;
520
    AVFilterPicRef *outpic;
521
};
522

    
523
/**
524
 * Links two filters together.
525
 * @param src    the source filter
526
 * @param srcpad index of the output pad on the source filter
527
 * @param dst    the destination filter
528
 * @param dstpad index of the input pad on the destination filter
529
 * @return       zero on success
530
 */
531
int avfilter_link(AVFilterContext *src, unsigned srcpad,
532
                  AVFilterContext *dst, unsigned dstpad);
533

    
534
/**
535
 * Negotiates the colorspace, dimensions, etc of all inputs to a filter.
536
 * @param filter the filter to negotiate the properties for its inputs
537
 * @return       zero on successful negotiation
538
 */
539
int avfilter_config_links(AVFilterContext *filter);
540

    
541
/**
542
 * Requests a picture buffer with a specific set of permissions.
543
 * @param link  the output link to the filter from which the picture will
544
 *              be requested
545
 * @param perms the required access permissions
546
 * @param w     the minimum width of the buffer to allocate
547
 * @param h     the minimum height of the buffer to allocate
548
 * @return      A reference to the picture. This must be unreferenced with
549
 *              avfilter_unref_pic when you are finished with it.
550
 */
551
AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms,
552
                                          int w, int h);
553

    
554
/**
555
 * Requests an input frame from the filter at the other end of the link.
556
 * @param link the input link
557
 * @return     zero on success
558
 */
559
int avfilter_request_frame(AVFilterLink *link);
560

    
561
/**
562
 * Polls a frame from the filter chain.
563
 * @param  link the input link
564
 * @return the number of immediately available frames, a negative
565
 * number in case of error
566
 */
567
int avfilter_poll_frame(AVFilterLink *link);
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569
/**
570
 * Notifies the next filter of the start of a frame.
571
 * @param link   the output link the frame will be sent over
572
 * @param picref A reference to the frame about to be sent. The data for this
573
 *               frame need only be valid once draw_slice() is called for that
574
 *               portion. The receiving filter will free this reference when
575
 *               it no longer needs it.
576
 */
577
void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref);
578

    
579
/**
580
 * Notifies the next filter that the current frame has finished.
581
 * @param link the output link the frame was sent over
582
 */
583
void avfilter_end_frame(AVFilterLink *link);
584

    
585
/**
586
 * Sends a slice to the next filter.
587
 *
588
 * Slices have to be provided in sequential order, either in
589
 * top-bottom or bottom-top order. If slices are provided in
590
 * non-sequential order the behavior of the function is undefined.
591
 *
592
 * @param link the output link over which the frame is being sent
593
 * @param y    offset in pixels from the top of the image for this slice
594
 * @param h    height of this slice in pixels
595
 * @param slice_dir the assumed direction for sending slices,
596
 *             from the top slice to the bottom slice if the value is 1,
597
 *             from the bottom slice to the top slice if the value is -1,
598
 *             for other values the behavior of the function is undefined.
599
 */
600
void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);
601

    
602
/** Initializes the filter system. Registers all builtin filters. */
603
void avfilter_register_all(void);
604

    
605
/** Uninitializes the filter system. Unregisters all filters. */
606
void avfilter_uninit(void);
607

    
608
/**
609
 * Registers a filter. This is only needed if you plan to use
610
 * avfilter_get_by_name later to lookup the AVFilter structure by name. A
611
 * filter can still by instantiated with avfilter_open even if it is not
612
 * registered.
613
 * @param filter the filter to register
614
 * @return 0 if the registration was succesfull, a negative value
615
 * otherwise
616
 */
617
int avfilter_register(AVFilter *filter);
618

    
619
/**
620
 * Gets a filter definition matching the given name.
621
 * @param name the filter name to find
622
 * @return     the filter definition, if any matching one is registered.
623
 *             NULL if none found.
624
 */
625
AVFilter *avfilter_get_by_name(const char *name);
626

    
627
/**
628
 * If filter is NULL, returns a pointer to the first registered filter pointer,
629
 * if filter is non-NULL, returns the next pointer after filter.
630
 * If the returned pointer points to NULL, the last registered filter
631
 * was already reached.
632
 */
633
AVFilter **av_filter_next(AVFilter **filter);
634

    
635
/**
636
 * Creates a filter instance.
637
 * @param filter    the filter to create an instance of
638
 * @param inst_name Name to give to the new instance. Can be NULL for none.
639
 * @return          Pointer to the new instance on success. NULL on failure.
640
 */
641
AVFilterContext *avfilter_open(AVFilter *filter, const char *inst_name);
642

    
643
/**
644
 * Initializes a filter.
645
 * @param filter the filter to initialize
646
 * @param args   A string of parameters to use when initializing the filter.
647
 *               The format and meaning of this string varies by filter.
648
 * @param opaque Any extra non-string data needed by the filter. The meaning
649
 *               of this parameter varies by filter.
650
 * @return       zero on success
651
 */
652
int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque);
653

    
654
/**
655
 * Destroys a filter.
656
 * @param filter the filter to destroy
657
 */
658
void avfilter_destroy(AVFilterContext *filter);
659

    
660
/**
661
 * Inserts a filter in the middle of an existing link.
662
 * @param link the link into which the filter should be inserted
663
 * @param filt the filter to be inserted
664
 * @param in   the input pad on the filter to connect
665
 * @param out  the output pad on the filter to connect
666
 * @return     zero on success
667
 */
668
int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
669
                           unsigned in, unsigned out);
670

    
671
/**
672
 * Inserts a new pad.
673
 * @param idx Insertion point. Pad is inserted at the end if this point
674
 *            is beyond the end of the list of pads.
675
 * @param count Pointer to the number of pads in the list
676
 * @param padidx_off Offset within an AVFilterLink structure to the element
677
 *                   to increment when inserting a new pad causes link
678
 *                   numbering to change
679
 * @param pads Pointer to the pointer to the beginning of the list of pads
680
 * @param links Pointer to the pointer to the beginning of the list of links
681
 * @param newpad The new pad to add. A copy is made when adding.
682
 */
683
void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
684
                         AVFilterPad **pads, AVFilterLink ***links,
685
                         AVFilterPad *newpad);
686

    
687
/** Inserts a new input pad for the filter. */
688
static inline void avfilter_insert_inpad(AVFilterContext *f, unsigned index,
689
                                         AVFilterPad *p)
690
{
691
    avfilter_insert_pad(index, &f->input_count, offsetof(AVFilterLink, dstpad),
692
                        &f->input_pads, &f->inputs, p);
693
}
694

    
695
/** Inserts a new output pad for the filter. */
696
static inline void avfilter_insert_outpad(AVFilterContext *f, unsigned index,
697
                                          AVFilterPad *p)
698
{
699
    avfilter_insert_pad(index, &f->output_count, offsetof(AVFilterLink, srcpad),
700
                        &f->output_pads, &f->outputs, p);
701
}
702

    
703
#endif  /* AVFILTER_AVFILTER_H */