* @return the position of the first byte of the next frame, or -1
*/
static int find_frame_end(MJPEGParserContext *m, const uint8_t *buf, int buf_size){
* @return the position of the first byte of the next frame, or -1
*/
static int find_frame_end(MJPEGParserContext *m, const uint8_t *buf, int buf_size){