typedef struct Packet Packet;typedef struct Packetctx Packetctx; typedef int (*packet_f)(Biobuf *out, Packetctx *ctx, Packet *p, int np, uvlong ts, int key); struct Packet {	uchar *data;	int sz;}; struct Packetctx {	uvlong frid;	uvlong duration;	uvlong seekpreroll;	vlong discardpad;	vlong blockdur;	struct {		char name[16];		vlong delay;		struct {			uchar *data;			int sz;		}priv;	}codec;	struct {		uchar *data;		int sz;		int algo;	}comp;	u32int trackuid;	u32int fmt; 	struct {		int width;		int height;	}video;	struct {		float samplerate;		float outsamplerate;		int channels;		int bps;	}audio; 	/* private stuff for packet_f functions */	uchar adts[7];	struct {		uchar *p;		int n;	}ps[16];	int nps;	int key;	int nonkey;	int kfgshift;}; int aacpacket(Biobuf *out, Packetctx *ctx, Packet *p, int np, uvlong ts, int key);int asspacket(Biobuf *out, Packetctx *ctx, Packet *p, int np, uvlong ts, int key);int ivfpacket(Biobuf *out, Packetctx *ctx, Packet *p, int np, uvlong ts, int key);int oggpacket(Biobuf *out, Packetctx *ctx, Packet *p, int np, uvlong ts, int key);int srtpacket(Biobuf *out, Packetctx *ctx, Packet *p, int np, uvlong ts, int key);