FFmpeg/libavfilter/avfiltergraph.h
Stefano Sabatini ab543afe47 Make avfilter_graph_free() free the graph.
Make avfilter_graph_free() free not only the internal structures, but
also the allocated graph, and set the graph pointer to NULL for
increased safety.

Simplify usage.

Signed-off-by: Mans Rullgard <mans@mansr.com>
(cherry picked from commit 4359288c56)
2011-02-06 20:31:42 +01:00

124 lines
4.0 KiB
C

/*
* Filter graphs
* 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_AVFILTERGRAPH_H
#define AVFILTER_AVFILTERGRAPH_H
#include "avfilter.h"
typedef struct AVFilterGraph {
unsigned filter_count;
AVFilterContext **filters;
char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
} AVFilterGraph;
/**
* Allocate a filter graph.
*/
AVFilterGraph *avfilter_graph_alloc(void);
/**
* Get a filter instance with name name from graph.
*
* @return the pointer to the found filter instance or NULL if it
* cannot be found.
*/
AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name);
/**
* Add an existing filter instance to a filter graph.
*
* @param graphctx the filter graph
* @param filter the filter to be added
*/
int avfilter_graph_add_filter(AVFilterGraph *graphctx, AVFilterContext *filter);
/**
* Create and add a filter instance into an existing graph.
* The filter instance is created from the filter filt and inited
* with the parameters args and opaque.
*
* In case of success put in *filt_ctx the pointer to the created
* filter instance, otherwise set *filt_ctx to NULL.
*
* @param name the instance name to give to the created filter instance
* @param graph_ctx the filter graph
* @return a negative AVERROR error code in case of failure, a non
* negative value otherwise
*/
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
const char *name, const char *args, void *opaque,
AVFilterGraph *graph_ctx);
/**
* Check validity and configure all the links and formats in the graph.
*
* @param graphctx the filter graph
* @param log_ctx context used for logging
* @return 0 in case of success, a negative AVERROR code otherwise
*/
int avfilter_graph_config(AVFilterGraph *graphctx, AVClass *log_ctx);
/**
* Free a graph, destroy its links, and set *graph to NULL.
* If *graph is NULL, do nothing.
*/
void avfilter_graph_free(AVFilterGraph **graph);
/**
* A linked-list of the inputs/outputs of the filter chain.
*
* This is mainly useful for avfilter_graph_parse(), since this
* function may accept a description of a graph with not connected
* input/output pads. This struct specifies, per each not connected
* pad contained in the graph, the filter context and the pad index
* required for establishing a link.
*/
typedef struct AVFilterInOut {
/** unique name for this input/output in the list */
char *name;
/** filter context associated to this input/output */
AVFilterContext *filter_ctx;
/** index of the filt_ctx pad to use for linking */
int pad_idx;
/** next input/input in the list, NULL if this is the last */
struct AVFilterInOut *next;
} AVFilterInOut;
/**
* Add a graph described by a string to a graph.
*
* @param graph the filter graph where to link the parsed graph context
* @param filters string to be parsed
* @param inputs linked list to the inputs of the graph
* @param outputs linked list to the outputs of the graph
* @return zero on success, a negative AVERROR code on error
*/
int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
AVFilterInOut *inputs, AVFilterInOut *outputs,
AVClass *log_ctx);
#endif /* AVFILTER_AVFILTERGRAPH_H */