@@ -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);

 }

@@ -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 {

@@ -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;

+}

@@ -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 */

@@ -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.

  *