src/main/java/org/jcodec/containers/mp4/QTTimeUtil.java
public static int qtPlayerFrameNo(MovieBox movie, int mediaFrameNo) {
        TrakBox videoTrack = movie.getVideoTrack();

        long editedTv = mediaToEdited(videoTrack, frameToTimevalue(videoTrack, mediaFrameNo), movie.getTimescale());

        return tv2QTFrameNo(movie, editedTv);
    }
public static int qtPlayerFrameNo(MovieBox movie, int mediaFrameNo) {
        TrakBox videoTrack = movie.getVideoTrack();

        long editedTv = mediaToEdited(videoTrack, frameToTimevalue(videoTrack, mediaFrameNo), movie.getTimescale());

        return tv2QTFrameNo(movie, editedTv);
    }
Calculates frame number as it shows in quicktime player

@param movie
@param mediaFrameNo
@return