Extracting frames from videos files

Question

Hi!
I'm looking for a Object that can help me to extract video component such as I-Frame, P-frame.
As a matter of fact, I would like to modify the DCT of I-Frame of a MPEG4 video file.
Thanks

Answer 1

if your file hold byte[] data you can use the following code to get the byte[] data as RGB
public byte[][] getData(int frameNum) throws Exception {
FramePositioningControl fpc = getPositionControl();
FrameGrabbingControl      fgc = getGrabControl();
Buffer           buf;
RGBFormat     format;
int          width, height, pixelStride, lineStride, idx;
byte[][]     rgbData;
byte[]          data;
Object          dataObj;
// skip to the requested frame
fpc.seek(frameNum);
// get the data
buf = fgc.grabFrame();
// support RGB Format
format = (RGBFormat)buf.getFormat();
width = format.getSize().width;
height = format.getSize().height;
pixelStride = format.getPixelStride();
lineStride = format.getLineStride();
dataObj = buf.getData();
if (!(dataObj instanceof byte[]))
return null;
data = (byte[])dataObj;
// create the data;
rgbData = new byte[3][width*height];
idx = 0;
for (int i = 0; i < data.length; i += pixelStride) {
// bgr order
rgbData[2][idx] = data;
rgbData[1][idx] = data[i+1];
rgbData[0][idx] = data[i+2];
idx++;
if (format.getFlipped() == 1) {
rgbData[0] = flipImageTopBottom(rgbData[0], width, height);
rgbData[1] = flipImageTopBottom(rgbData[1], width, height);
rgbData[2] = flipImageTopBottom(rgbData[2], width, height);
return rgbData;