* Filter graphs
* copyright (c) 2007 Bobby Bingham
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * 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.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * 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 FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#ifndef FFMPEG_AVFILTERGRAPH_H
-#define FFMPEG_AVFILTERGRAPH_H
+#ifndef AVFILTER_AVFILTERGRAPH_H
+#define AVFILTER_AVFILTERGRAPH_H
#include "avfilter.h"
+#include "libavutil/log.h"
-/** Linked-list of filters to create for an AVFilterGraphDesc */
-typedef struct AVFilterGraphDescFilter
-{
- char *name; ///< filter instance name
- char *filter; ///< name of filter type
- char *args; ///< filter parameters
- struct AVFilterGraphDescFilter *next;
-} AVFilterGraphDescFilter;
-
-/** Linked-list of links between filters */
-typedef struct AVFilterGraphDescLink
-{
- /* TODO: allow referencing pads by name, not just by index */
- char *src; ///< name of the source filter
- unsigned srcpad; ///< index of the output pad on the source filter
-
- char *dst; ///< name of the dest filter
- unsigned dstpad; ///< index of the input pad on the dest filter
-
- struct AVFilterGraphDescLink *next;
-} AVFilterGraphDescLink;
-
-/** Linked-list of filter pads to be exported from the graph */
-typedef struct AVFilterGraphDescExport
-{
- /* TODO: allow referencing pads by name, not just by index */
- char *name; ///< name of the exported pad
- char *filter; ///< name of the filter
- unsigned pad; ///< index of the pad to be exported
-
- struct AVFilterGraphDescExport *next;
-} AVFilterGraphDescExport;
-
-/** Sections of a filter graph description */
-typedef enum
-{
- SEC_NONE = 0,
- SEC_FILTERS,
- SEC_LINKS,
- SEC_INPUTS,
- SEC_OUTPUTS
-} AVFilterGraphDescSection;
-
-/** Description of a graph to be loaded from a file, etc */
-typedef struct
-{
- AVFilterGraphDescFilter *filters; ///< filters in the graph
- AVFilterGraphDescLink *links; ///< links between the filters
- AVFilterGraphDescExport *inputs; ///< inputs to export
- AVFilterGraphDescExport *outputs; ///< outputs to export
-} AVFilterGraphDesc;
-
-typedef struct
-{
- AVFilterGraphDescSection section; ///< current section being parsed
-
- AVFilterGraphDescFilter **filterp; ///< last parsed filter
- AVFilterGraphDescLink **linkp; ///< last parsed link
- AVFilterGraphDescExport **inputp; ///< last parsed exported input
- AVFilterGraphDescExport **outputp; ///< last parsed exported output
-} AVFilterGraphDescParser;
-
-extern AVFilter avfilter_vf_graph;
-extern AVFilter avfilter_vf_graphfile;
-extern AVFilter avfilter_vf_graphdesc;
+typedef struct AVFilterGraph {
+#if FF_API_GRAPH_AVCLASS
+ const AVClass *av_class;
+#endif
+ unsigned filter_count;
+ AVFilterContext **filters;
+
+ char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
+} AVFilterGraph;
/**
- * Parse a graph composed of a simple chain of filters which is described by
- * a single string.
- * @param filters String listing filters and their arguments.
- * @return The parsed graph description.
+ * Allocate a filter graph.
*/
-AVFilterGraphDesc *avfilter_graph_parse_chain(const char *filters);
-
-/** Parse a line of a filter graph description.
- * @param desc Pointer to an AVFilterGraphDesc pointer. If *desc is NULL,
- * a new AVFilterGraphDesc structure will be created for you.
- * Must be the same between multiple invocations when parsing
- * the same description.
- * @param parser Parser state. Must be the same between multiple invocations
- * when parsing the same description
- * @param line Line of the graph description to parse.
- * @return Zero on success, negative on error.
+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.
*/
-int avfilter_graph_parse_desc(AVFilterGraphDesc **desc,
- AVFilterGraphDescParser **parser,
- char *line);
+AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name);
/**
- * Load a filter graph description from a file.
- * @param filename Name of the file from which to load the description.
- * @return Pointer to the description on success, NULL on failure.
+ * Add an existing filter instance to a filter graph.
+ *
+ * @param graphctx the filter graph
+ * @param filter the filter to be added
*/
-AVFilterGraphDesc *avfilter_graph_load_desc(const char *filename);
+int avfilter_graph_add_filter(AVFilterGraph *graphctx, AVFilterContext *filter);
/**
- * Free a filter graph description.
- * @param desc The graph description to free
+ * 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
*/
-void avfilter_graph_free_desc(AVFilterGraphDesc *desc);
+int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
+ const char *name, const char *args, void *opaque,
+ AVFilterGraph *graph_ctx);
/**
- * Add an existing filter instance to a filter graph.
- * @param graph The filter graph
- * @param filter The filter to be added
+ * 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
*/
-void avfilter_graph_add_filter(AVFilterContext *graphctx, AVFilterContext *filter);
+int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
/**
- * Configure the formats of all the links in the graph.
+ * Free a graph, destroy its links, and set *graph to NULL.
+ * If *graph is NULL, do nothing.
*/
-int avfilter_graph_config_formats(AVFilterContext *graphctx);
+void avfilter_graph_free(AVFilterGraph **graph);
/**
- * Configure the parameters (resolution, etc) of all links in the graph.
+ * A linked-list of the inputs/outputs of the filter chain.
+ *
+ * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
+ * where it is used to communicate open (unlinked) inputs and outputs from and
+ * to the caller.
+ * 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;
+
+/**
+ * Allocate a single AVFilterInOut entry.
+ * Must be freed with avfilter_inout_free().
+ * @return allocated AVFilterInOut on success, NULL on failure.
+ */
+AVFilterInOut *avfilter_inout_alloc(void);
+
+/**
+ * Free the supplied list of AVFilterInOut and set *inout to NULL.
+ * If *inout is NULL, do nothing.
+ */
+void avfilter_inout_free(AVFilterInOut **inout);
+
+/**
+ * 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,
+ void *log_ctx);
+
+/**
+ * Add a graph described by a string to a graph.
+ *
+ * @param[in] graph the filter graph where to link the parsed graph context
+ * @param[in] filters string to be parsed
+ * @param[out] inputs a linked list of all free (unlinked) inputs of the
+ * parsed graph will be returned here. It is to be freed
+ * by the caller using avfilter_inout_free().
+ * @param[out] outputs a linked list of all free (unlinked) outputs of the
+ * parsed graph will be returned here. It is to be freed by the
+ * caller using avfilter_inout_free().
+ * @return zero on success, a negative AVERROR code on error
+ *
+ * @note the difference between avfilter_graph_parse2() and
+ * avfilter_graph_parse() is that in avfilter_graph_parse(), the caller provides
+ * the lists of inputs and outputs, which therefore must be known before calling
+ * the function. On the other hand, avfilter_graph_parse2() \em returns the
+ * inputs and outputs that are left unlinked after parsing the graph and the
+ * caller then deals with them. Another difference is that in
+ * avfilter_graph_parse(), the inputs parameter describes inputs of the
+ * <em>already existing</em> part of the graph; i.e. from the point of view of
+ * the newly created part, they are outputs. Similarly the outputs parameter
+ * describes outputs of the already existing filters, which are provided as
+ * inputs to the parsed filters.
+ * avfilter_graph_parse2() takes the opposite approach -- it makes no reference
+ * whatsoever to already existing parts of the graph and the inputs parameter
+ * will on return contain inputs of the newly parsed part of the graph.
+ * Analogously the outputs parameter will contain outputs of the newly created
+ * filters.
*/
-int avfilter_graph_config_links(AVFilterContext *graphctx);
+int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
+ AVFilterInOut **inputs,
+ AVFilterInOut **outputs);
-#endif /* FFMPEG_AVFILTERGRAPH_H */
+#endif /* AVFILTER_AVFILTERGRAPH_H */