PeerStreamer

/*

 * 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);

/**

 * Check for the validity of graph.

 *

 * A graph is considered valid if all its input and output pads are

 * connected.

 *

 * @return 0 in case of success, a negative value otherwise

 */

int avfilter_graph_check_validity(AVFilterGraph *graphctx, AVClass *log_ctx);

/**

 * Configure all the links of graphctx.

 *

 * @return 0 in case of success, a negative value otherwise

 */

int avfilter_graph_config_links(AVFilterGraph *graphctx, AVClass *log_ctx);

/**

 * Configure the formats of all the links in the graph.

 */

int avfilter_graph_config_formats(AVFilterGraph *graphctx, AVClass *log_ctx);

/**

 * Check validity and configure all the links and formats in the graph.

 *

 * @see avfilter_graph_check_validity(), avfilter_graph_config_links(),

 * avfilter_graph_config_formats()

 */

int avfilter_graph_config(AVFilterGraph *graphctx, AVClass *log_ctx);

/**

 * Free a graph and destroy its links.

 */

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 */