ihmcrobotics/ihmc-video-codecs

This library provides a Java library for H264 and MJPEG encoding and decoding as well as support for MP4.

ihmc-video-codecs's Issues

Optimize for YUV420

@calvertdw, I am using your library to encode YUV420 to H264, really appreciate your effort.

Right now I am trying to optimize the performance for my encoder, and I noticed that I have to slice my YUV420 ByteBuffer into 3 ByteBuffer objects and copy the data from the buffer into U and V buffers (Tried to re-use the same ByteBuffer but couldn't figure out a way, could be due to my lack of experience), I wonder whether we could add a new constructor like this one which takes a single YUV420 buffer:

`// Constructor dedicated for YUV420
YUVPicture::YUVPicture(int width, int height, int yStride, int uStride, int vStride, uint8 *in) :
type(type), width(width), height(height), yStride(yStride), uStride(uStride), vStride(vStride) {

int ySize = yStride * height;
int uSize = uStride * YUVPicture::divideByTwoRoundUp(height);
int vSize = vStride * YUVPicture::divideByTwoRoundUp(height);

Y = (uint8*) malloc(ySize);
U = (uint8*) malloc(uSize);
V = (uint8*) malloc(vSize);

memcpy(Y, in, ySize);
memcpy(U, in + width, uSize);
memcpy(V, in + (width / 4), vSize);

}
`
I did some profiling in my Java code, it takes around 100ms to slice YUV buffer into 3 for 30 full HD frames, so the performance improvement is not trivial. And since it's YUV420 frame, so we may be able to simplify the above constructor to derive yuvStride from width and height.