@@ -171,6 +171,12 @@ avconv -i in.avi -f image2 -frames:v 1 img.jpeg

 @table @option

 @item -start_number @var{number}

 Start the sequence from @var{number}.

+

+@item -update @var{number}

+If @var{number} is nonzero, the filename will always be interpreted as just a

+filename, not a pattern, and this file will be continuously overwritten with new

+images.

+

 @end table

 @section MOV/MP4/ISMV

@@ -33,6 +33,7 @@ typedef struct {

     int img_number;

     int is_pipe;

     char path[1024];

+    int update;

 } VideoMuxData;

 static int write_header(AVFormatContext *s)

@@ -59,8 +60,10 @@ static int write_packet(AVFormatContext *s, AVPacket *pkt)

     int i;

     if (!img->is_pipe) {

-        if (av_get_frame_filename(filename, sizeof(filename),

-                                  img->path, img->img_number) < 0 && img->img_number > 1) {

+        if (img->update) {

+            av_strlcpy(filename, img->path, sizeof(filename));

+        } else if (av_get_frame_filename(filename, sizeof(filename), img->path, img->img_number) < 0 &&

+                   img->img_number > 1) {

             av_log(s, AV_LOG_ERROR,

                    "Could not get frame filename number %d from pattern '%s'\n",

                    img->img_number, img->path);

@@ -128,6 +131,7 @@ error:

 #define ENC AV_OPT_FLAG_ENCODING_PARAM

 static const AVOption muxoptions[] = {

     { "start_number", "first number in the sequence", OFFSET(img_number), AV_OPT_TYPE_INT, { .i64 = 1 }, 1, INT_MAX, ENC },

+    { "update",       "continuously overwrite one file", OFFSET(update),  AV_OPT_TYPE_INT, { .i64 = 0 }, 0,       1, ENC },

     { NULL },

 };