ref: eac7952b194921bd8792d5d35675bd7a4721c8cf
dir: /frame.h/
typedef struct Frame Frame; struct Frame { uvlong dt; int w, h; struct { int left, top, right, bottom; }crop; u8int *yuv[3]; int ystride; int uvstride; u8int data[1]; }; Frame *newframe(int w, int h, u8int *yuv[3], int ystride, int vstride);