avfilter: Add avfilter_graph_que_command()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavfilter/avfilter.c

@@ -45,6 +45,15 @@ const char *avfilter_license(void)
     return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;
 }
 
+static void command_queue_pop(AVFilterContext *filter)
+{
+    AVFilterCommand *c= filter->command_queue;
+    av_freep(&c->arg);
+    av_freep(&c->command);
+    filter->command_queue= c->next;
+    av_free(c);
+}
+
 AVFilterBufferRef *avfilter_ref_buffer(AVFilterBufferRef *ref, int pmask)
 {
     AVFilterBufferRef *ret = av_malloc(sizeof(AVFilterBufferRef));
@@ -534,6 +543,7 @@ void avfilter_start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
     void (*start_frame)(AVFilterLink *, AVFilterBufferRef *);
     AVFilterPad *dst = link->dstpad;
     int perms = picref->perms;
+    AVFilterCommand *cmd= link->dst->command_queue;
 
     FF_DPRINTF_START(NULL, start_frame); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " "); ff_dlog_ref(NULL, picref, 1);
 
@@ -556,6 +566,11 @@ void avfilter_start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
     else
         link->cur_buf = picref;
 
+    if(cmd && cmd->time <= picref->pts * av_q2d(link->time_base)){
+        avfilter_process_command(link->dst, cmd->command, cmd->arg, 0, 0, cmd->flags);
+        command_queue_pop(link->dst);
+    }
+
     start_frame(link, link->cur_buf);
 }
 
@@ -815,6 +830,9 @@ void avfilter_free(AVFilterContext *filter)
     av_freep(&filter->inputs);
     av_freep(&filter->outputs);
     av_freep(&filter->priv);
+    while(filter->command_queue){
+        command_queue_pop(filter);
+    }
     av_free(filter);
 }
 

libavfilter/avfilter.h

@@ -29,7 +29,7 @@
 #include "libavutil/rational.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  2
-#define LIBAVFILTER_VERSION_MINOR 36
+#define LIBAVFILTER_VERSION_MINOR 37
 #define LIBAVFILTER_VERSION_MICRO  0
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
@@ -585,6 +585,8 @@ struct AVFilterContext {
     AVFilterLink **outputs;         ///< array of pointers to output links
 
     void *priv;                     ///< private data for use by the filter
+
+    struct AVFilterCommand *command_queue;
 };
 
 enum AVFilterPacking {

libavfilter/avfiltergraph.c

@@ -283,3 +283,28 @@ int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const
 
     return r;
 }
+
+int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *command, const char *arg, int flags, double ts)
+{
+    int i;
+
+    if(!graph)
+        return 0;
+
+    for (i = 0; i < graph->filter_count; i++) {
+        AVFilterContext *filter = graph->filters[i];
+        if(filter && (!strcmp(target, "all") || !strcmp(target, filter->name) || !strcmp(target, filter->filter->name))){
+            AVFilterCommand **que = &filter->command_queue;
+            while(*que) que = &(*que)->next;
+            *que= av_mallocz(sizeof(AVFilterCommand));
+            (*que)->command = av_strdup(command);
+            (*que)->arg     = av_strdup(arg);
+            (*que)->time    = ts;
+            (*que)->flags   = flags;
+            if(flags & AVFILTER_CMD_FLAG_ONE)
+                return 0;
+        }
+    }
+
+    return 0;
+}

libavfilter/avfiltergraph.h

@@ -153,4 +153,22 @@ int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
  */
 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
 
+/**
+ * Queue a command for one or more filter instances.
+ *
+ * @param graph  the filter graph
+ * @param target the filter(s) to which the command should be sent
+ *               "all" sends to all filters
+ *               otherwise it can be a filter or filter instance name
+ *               which will send the command to all matching filters.
+ * @param cmd    the command to sent, for handling simplicity all commands must be alphanummeric only
+ * @param arg    the argument for the command
+ * @param ts     time at which the command should be sent to the filter
+ *
+ * @note As this executes commands after this function returns, no return code
+ *       from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
+ */
+int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
+
+
 #endif /* AVFILTER_AVFILTERGRAPH_H */

libavfilter/internal.h

@@ -33,6 +33,13 @@ typedef struct AVFilterPool {
     int count;
 } AVFilterPool;
 
+typedef struct AVFilterCommand {
+    double time;
+    char *command, *arg;
+    int flags;
+    struct AVFilterCommand *next;
+} AVFilterCommand;
+
 /**
  * Check for the validity of graph.
  *