ffmpeg/libavfilter/internal.h

215 lines
6.9 KiB
C

/*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVFILTER_INTERNAL_H
#define AVFILTER_INTERNAL_H
/**
* @file
* internal API functions
*/
#include "avfilter.h"
#if !FF_API_AVFILTERPAD_PUBLIC
/**
* 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.
*/
enum AVMediaType type;
/**
* Callback function to get a video buffer. If NULL, the filter system will
* use avfilter_default_get_video_buffer().
*
* Input video pads only.
*/
AVFrame *(*get_video_buffer)(AVFilterLink *link, int w, int h);
/**
* Callback function to get an audio buffer. If NULL, the filter system will
* use avfilter_default_get_audio_buffer().
*
* Input audio pads only.
*/
AVFrame *(*get_audio_buffer)(AVFilterLink *link, int nb_samples);
/**
* Filtering callback. This is where a filter receives a frame with
* audio/video data and should do its processing.
*
* Input pads only.
*
* @return >= 0 on success, a negative AVERROR on error. This function
* must ensure that samplesref is properly unreferenced on error if it
* hasn't been passed on to another filter.
*/
int (*filter_frame)(AVFilterLink *link, AVFrame *frame);
/**
* Frame poll callback. This returns the number of immediately available
* samples. 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 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 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);
/**
* The filter expects a fifo to be inserted on its input link,
* typically because it has a delay.
*
* input pads only.
*/
int needs_fifo;
};
#endif
/** default handler for freeing audio/video buffer when there are no references left */
void ff_avfilter_default_free_buffer(AVFilterBuffer *buf);
/** Tell is a format is contained in the provided list terminated by -1. */
int ff_fmt_is_in(int fmt, const int *fmts);
#define FF_DPRINTF_START(ctx, func) av_dlog(NULL, "%-16s: ", #func)
void ff_dlog_link(void *ctx, AVFilterLink *link, int end);
/**
* Insert 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 ff_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
AVFilterPad **pads, AVFilterLink ***links,
AVFilterPad *newpad);
/** Insert a new input pad for the filter. */
static inline void ff_insert_inpad(AVFilterContext *f, unsigned index,
AVFilterPad *p)
{
ff_insert_pad(index, &f->nb_inputs, offsetof(AVFilterLink, dstpad),
&f->input_pads, &f->inputs, p);
#if FF_API_FOO_COUNT
f->input_count = f->nb_inputs;
#endif
}
/** Insert a new output pad for the filter. */
static inline void ff_insert_outpad(AVFilterContext *f, unsigned index,
AVFilterPad *p)
{
ff_insert_pad(index, &f->nb_outputs, offsetof(AVFilterLink, srcpad),
&f->output_pads, &f->outputs, p);
#if FF_API_FOO_COUNT
f->output_count = f->nb_outputs;
#endif
}
/**
* Poll 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 ff_poll_frame(AVFilterLink *link);
/**
* Request an input frame from the filter at the other end of the link.
*
* @param link the input link
* @return zero on success
*/
int ff_request_frame(AVFilterLink *link);
/**
* Send a frame of data to the next filter.
*
* @param link the output link over which the data is being sent
* @param frame a reference to the buffer of data being sent. The
* receiving filter will free this reference when it no longer
* needs it or pass it on to the next filter.
*
* @return >= 0 on success, a negative AVERROR on error. The receiving filter
* is responsible for unreferencing frame in case of error.
*/
int ff_filter_frame(AVFilterLink *link, AVFrame *frame);
/**
* Allocate a new filter context and return it.
*
* @param filter what filter to create an instance of
* @param inst_name name to give to the new filter context
*
* @return newly created filter context or NULL on failure
*/
AVFilterContext *ff_filter_alloc(const AVFilter *filter, const char *inst_name);
/**
* Remove a filter from a graph;
*/
void ff_filter_graph_remove_filter(AVFilterGraph *graph, AVFilterContext *filter);
#endif /* AVFILTER_INTERNAL_H */