FS-8380 Improve mod_av's handling of vw and vh core file params

This allows for the core file params vw and vh to be used to modify the
resolution of recordings. If the specified resolution does not match
the resolution of the call being recorded, the video will be scaled.

src/mod/applications/mod_av/avformat.c

@@ -513,7 +513,7 @@ static void *SWITCH_THREAD_FUNC video_thread_run(switch_thread_t *thread, void *
 	record_helper_t *eh = (record_helper_t *) obj;
 	void *pop = NULL;
 	switch_image_t *img = NULL, *tmp_img = NULL;
-	int d_w = 0, d_h = 0;
+	int d_w = eh->video_st->width, d_h = eh->video_st->height;
 	int size = 0, skip = 0, skip_freq = 0, skip_count = 0, skip_total = 0, skip_total_count = 0;
 
 	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_NOTICE, "video thread start\n");