src/main/java/org/jcodec/api/FrameGrab.java
public static Picture getNativeFrameAtSec(SeekableDemuxerTrack vt, ContainerAdaptor decoder, double second)
            throws IOException, JCodecException {
        return new FrameGrab(vt, decoder).seekToSecondPrecise(second).getNativeFrame();
    }
public static Picture getNativeFrameAtSec(SeekableDemuxerTrack vt, ContainerAdaptor decoder, double second)
            throws IOException, JCodecException {
        return new FrameGrab(vt, decoder).seekToSecondPrecise(second).getNativeFrame();
    }
Get a specified frame by second from an already open demuxer track

@param vt
@param decoder
@param frameNumber
@return
@throws IOException
@throws JCodecException