@@ -26,6 +26,7 @@

 #include "libavutil/audioconvert.h"

 #include "libavutil/imgutils.h"

 #include "libavutil/avassert.h"

+#include "libavutil/avstring.h"

 #include "avfilter.h"

 #include "internal.h"

@@ -616,6 +617,17 @@ void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)

     draw_slice(link, y, h, slice_dir);

 }

+int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags)

+{

+    if(!strcmp(cmd, "ping")){

+        av_strlcatf(res, res_len, "pong from:%s %s\n", filter->filter->name, filter->name);

+        return 0;

+    }else if(filter->filter->process_command) {

+        return filter->filter->process_command(filter, cmd, arg, res, res_len, flags);

+    }

+    return AVERROR(ENOSYS);

+}

+

 void avfilter_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref)

 {

     void (*filter_samples)(AVFilterLink *, AVFilterBufferRef *);

@@ -29,7 +29,7 @@

 #include "libavutil/rational.h"

 #define LIBAVFILTER_VERSION_MAJOR  2

-#define LIBAVFILTER_VERSION_MINOR 35

+#define LIBAVFILTER_VERSION_MINOR 36

 #define LIBAVFILTER_VERSION_MICRO  0

 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \

@@ -552,6 +552,20 @@ typedef struct AVFilter {

      * NULL_IF_CONFIG_SMALL() macro to define it.

      */

     const char *description;

+

+    /**

+     * Make the filter instance process a command.

+     *

+     * @param cmd    the command to process, for handling simplicity all commands must be alphanumeric only

+     * @param arg    the argument for the command

+     * @param res    a buffer with size res_size where the filter(s) can return a response. This must not change when the command is not supported.

+     * @param flags  if AVFILTER_CMD_FLAG_FAST is set and the command would be

+     *               timeconsuming then a filter should treat it like an unsupported command

+     *

+     * @returns >=0 on success otherwise an error code.

+     *          AVERROR(ENOSYS) on unsupported commands

+     */

+    int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags);

 } AVFilter;

 /** An instance of a filter */

@@ -791,6 +805,15 @@ void avfilter_end_frame(AVFilterLink *link);

  */

 void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir);

+#define AVFILTER_CMD_FLAG_ONE   1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically

+#define AVFILTER_CMD_FLAG_FAST  2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw)

+

+/**

+ * Make the filter instance process a command.

+ * It is recommanded to use avfilter_graph_send_command().

+ */

+int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags);

+

 /**

  * Send a buffer of audio samples to the next filter.

  *

@@ -253,3 +253,33 @@ int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)

     return 0;

 }

+

+int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags)

+{

+    int i, r = AVERROR(ENOSYS);

+

+    if(!graph)

+        return r;

+

+    if((flags & AVFILTER_CMD_FLAG_ONE) && !(flags & AVFILTER_CMD_FLAG_FAST)) {

+        r=avfilter_graph_send_command(graph, target, cmd, arg, res, res_len, flags | AVFILTER_CMD_FLAG_FAST);

+        if(r != AVERROR(ENOSYS))

+            return r;

+    }

+

+    if(res_len && res)

+        res[0]= 0;

+

+    for (i = 0; i < graph->filter_count; i++) {

+        AVFilterContext *filter = graph->filters[i];

+        if(!strcmp(target, "all") || !strcmp(target, filter->name) || !strcmp(target, filter->filter->name)){

+            r = avfilter_process_command(filter, cmd, arg, res, res_len, flags);

+            if(r != AVERROR(ENOSYS)) {

+                if((flags & AVFILTER_CMD_FLAG_ONE) || r<0)

+                    return r;

+            }

+        }

+    }

+

+    return r;

+}

@@ -136,4 +136,21 @@ int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,

                          AVFilterInOut **inputs, AVFilterInOut **outputs,

                          void *log_ctx);

+/**

+ * Send a command to 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 alphanumeric only

+ * @param arg    the argument for the command

+ * @param res    a buffer with size res_size where the filter(s) can return a response.

+ *

+ * @returns >=0 on success otherwise an error code.

+ *              AVERROR(ENOSYS) on unsupported commands

+ */

+int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);

+

 #endif /* AVFILTER_AVFILTERGRAPH_H */