Merge pull request #1 from cnadler86/AvailableFramesPR

Available frames pr from espressif#723

Author: cnadler86

driver/cam_hal.c

@@ -535,3 +535,8 @@ void cam_give_all(void) {
         cam_obj->frames[x].en = 1;
     }
 }
+
+bool cam_get_available_frames(void)
+{
+    return 0 < uxQueueMessagesWaiting(cam_obj->frame_buffer_queue);
+}

driver/esp_camera.c

@@ -490,3 +490,10 @@ void esp_camera_return_all(void) {
     cam_give_all();
 }
 
+bool esp_camera_available_frames(void)
+{
+    if (s_state == NULL) {
+        return false;
+    }
+    return cam_get_available_frames();
+}

driver/include/esp_camera.h

@@ -240,6 +240,11 @@ esp_err_t esp_camera_load_from_nvs(const char *key);
  */
 void esp_camera_return_all(void);
 
+/**
+ * @brief Check if there are available frames to be immediately acquired
+ */
+bool esp_camera_available_frames(void);
+
 
 #ifdef __cplusplus
 }

driver/private_include/cam_hal.h

@@ -57,6 +57,8 @@ void cam_give(camera_fb_t *dma_buffer);
 
 void cam_give_all(void);
 
+bool cam_get_available_frames(void);
+
 #ifdef __cplusplus
 }
 #endif