Add avfilter_graph_create_filter().

Originally committed as revision 25862 to svn://svn.ffmpeg.org/ffmpeg/trunk

3 files changed, 45 insertions, 12 deletions

diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index f7aaf7fb6d..4dea65310c 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -25,7 +25,7 @@
 #include "libavutil/avutil.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  1
-#define LIBAVFILTER_VERSION_MINOR 66
+#define LIBAVFILTER_VERSION_MINOR 67
 #define LIBAVFILTER_VERSION_MICRO  0
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
diff --git a/libavfilter/avfiltergraph.c b/libavfilter/avfiltergraph.c
index 97dd120d89..8a258912df 100644
--- a/libavfilter/avfiltergraph.c
+++ b/libavfilter/avfiltergraph.c
@@ -53,6 +53,27 @@ int avfilter_graph_add_filter(AVFilterGraph *graph, AVFilterContext *filter)
     return 0;
 }
 
+int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
+                                 const char *name, const char *args, void *opaque,
+                                 AVFilterGraph *graph_ctx)
+{
+    int ret;
+
+    if ((ret = avfilter_open(filt_ctx, filt, name)) < 0)
+        goto fail;
+    if ((ret = avfilter_init_filter(*filt_ctx, args, opaque)) < 0)
+        goto fail;
+    if ((ret = avfilter_graph_add_filter(graph_ctx, *filt_ctx)) < 0)
+        goto fail;
+    return 0;
+
+fail:
+    if (*filt_ctx)
+        avfilter_free(*filt_ctx);
+    *filt_ctx = NULL;
+    return ret;
+}
+
 int ff_avfilter_graph_check_validity(AVFilterGraph *graph, AVClass *log_ctx)
 {
     AVFilterContext *filt;
@@ -113,7 +134,7 @@ AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name)
 
 static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
 {
-    int i, j;
+    int i, j, ret;
     int scaler_count = 0;
     char inst_name[30];
 
@@ -139,17 +160,12 @@ static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
                     /* couldn't merge format lists. auto-insert scale filter */
                     snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d",
                              scaler_count++);
-                    avfilter_open(&scale, avfilter_get_by_name("scale"), inst_name);
-
                     snprintf(scale_args, sizeof(scale_args), "0:0:%s", graph->scale_sws_opts);
-                    if(!scale || scale->filter->init(scale, scale_args, NULL) ||
-                                 avfilter_insert_filter(link, scale, 0, 0)) {
-                        avfilter_free(scale);
-                        return -1;
-                    }
-
-                    if (avfilter_graph_add_filter(graph, scale) < 0)
-                        return -1;
+                    if ((ret = avfilter_graph_create_filter(&scale, avfilter_get_by_name("scale"),
+                                                            inst_name, scale_args, NULL, graph)) < 0)
+                        return ret;
+                    if ((ret = avfilter_insert_filter(link, scale, 0, 0)) < 0)
+                        return ret;
 
                     scale->filter->query_formats(scale);
                     if (((link = scale-> inputs[0]) &&
diff --git a/libavfilter/avfiltergraph.h b/libavfilter/avfiltergraph.h
index ca369aa589..74d7a12812 100644
--- a/libavfilter/avfiltergraph.h
+++ b/libavfilter/avfiltergraph.h
@@ -53,6 +53,23 @@ AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name);
 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