* if d is non-NULL, returns the next registered input audio/video device after d
* or NULL if d is the last one.
*/
-AVInputFormat *av_input_audio_device_next(AVInputFormat *d);
+const AVInputFormat *av_input_audio_device_next(const AVInputFormat *d);
/**
* Video input devices iterator.
* if d is non-NULL, returns the next registered input audio/video device after d
* or NULL if d is the last one.
*/
-AVInputFormat *av_input_video_device_next(AVInputFormat *d);
+const AVInputFormat *av_input_video_device_next(const AVInputFormat *d);
/**
* Audio output devices iterator.
* if d is non-NULL, returns the next registered output audio/video device after d
* or NULL if d is the last one.
*/
-AVOutputFormat *av_output_audio_device_next(AVOutputFormat *d);
+const AVOutputFormat *av_output_audio_device_next(const AVOutputFormat *d);
/**
* Video output devices iterator.
* if d is non-NULL, returns the next registered output audio/video device after d
* or NULL if d is the last one.
*/
-AVOutputFormat *av_output_video_device_next(AVOutputFormat *d);
+const AVOutputFormat *av_output_video_device_next(const AVOutputFormat *d);
typedef struct AVDeviceRect {
int x; /**< x coordinate of top left corner */