call bink2w32.dll to extract the raw sound

extract_bink_pcm.c

#include <windows.h>
#include <stdio.h>

typedef void* (__stdcall *BinkOpen_t)(const char*, unsigned);
typedef void (__stdcall *BinkNextFrame_t)(void*);
typedef void (__stdcall *BinkClose_t)(void*);
typedef int (__stdcall *BinkSetVideoOnOff_t)(void*, int);
typedef void* (__stdcall *BinkOpenTrack_t)(void*, unsigned);
typedef void (__stdcall *BinkCloseTrack_t)(void*);
typedef unsigned (__stdcall *BinkGetTrackData_t)(void*, void*);
typedef void (__stdcall *BinkSetSoundTrack_t)(unsigned, unsigned*);

int main(int argc, const char* argv[])
{
	if (argc != 3) {
		printf("Usage: extract_pcm <input.bk2> <output.pcm>\n");
		return 1;
	}
	HANDLE bink2w32 = LoadLibrary(TEXT("bink2w32.dll"));
	if (!bink2w32) {
		printf("failed to load bink2w32.dll\n");
		return 1;
	}
	BinkOpen_t BinkOpen = (BinkOpen_t)GetProcAddress(bink2w32, "_BinkOpen@8");
	BinkNextFrame_t BinkNextFrame = (BinkNextFrame_t)GetProcAddress(bink2w32, "_BinkNextFrame@4");
	BinkClose_t BinkClose = (BinkClose_t)GetProcAddress(bink2w32, "_BinkClose@4");
	BinkSetVideoOnOff_t BinkSetVideoOnOff = (BinkSetVideoOnOff_t)GetProcAddress(bink2w32, "_BinkSetVideoOnOff@8");
	BinkOpenTrack_t BinkOpenTrack = (BinkOpenTrack_t)GetProcAddress(bink2w32, "_BinkOpenTrack@8");
	BinkCloseTrack_t BinkCloseTrack = (BinkCloseTrack_t)GetProcAddress(bink2w32, "_BinkCloseTrack@4");
	BinkGetTrackData_t BinkGetTrackData = (BinkGetTrackData_t)GetProcAddress(bink2w32, "_BinkGetTrackData@8");
	BinkSetSoundTrack_t BinkSetSoundTrack = (BinkSetSoundTrack_t)GetProcAddress(bink2w32, "_BinkSetSoundTrack@8");
	if (!BinkOpen || !BinkNextFrame || !BinkClose || !BinkSetVideoOnOff || !BinkOpenTrack || !BinkCloseTrack || !BinkGetTrackData || !BinkSetSoundTrack) {
		printf("required functions not found\n");
		FreeLibrary(bink2w32);
		return 1;
	}
	BinkSetSoundTrack(0, NULL);
	// 0x400 = don't allocate frame buffers, we're not interested in video anyway
	// 0x4000 = use data from BinkSetSoundTrack
	void* bink = BinkOpen(argv[1], 0x4400);
	if (!bink) {
		printf("failed to open %s\n", argv[1]);
		FreeLibrary(bink2w32);
		return 1;
	}
	BinkSetVideoOnOff(bink, 0);
	void* track = BinkOpenTrack(bink, 0);
	if (!track) {
		printf("failed to open track\n");
		BinkClose(bink);
		FreeLibrary(bink2w32);
		return 1;
	}
	unsigned largestAudio = ((unsigned*)track)[3];
	void* pcm = malloc(largestAudio + 0x20);
	if (!pcm) {
		printf("failed to allocate memory\n");
		BinkCloseTrack(track);
		BinkClose(bink);
		FreeLibrary(bink2w32);
		return 1;
	}
	void* pcm_aligned = (char*)pcm + (-(unsigned)pcm & 0x1F);
	FILE* out = fopen(argv[2], "wb");
	if (!out) {
		printf("failed to create %s\n", argv[2]);
		free(pcm);
		BinkCloseTrack(track);
		BinkClose(bink);
		FreeLibrary(bink2w32);
		return 1;
	}
	int ret = 0;
	for (;;) {
		unsigned n = BinkGetTrackData(track, pcm_aligned);
		if (n > largestAudio) printf("internal error\n");
		if (fwrite(pcm_aligned, 1, n, out) != n) {
			printf("write error\n");
			ret = 1;
			break;
		}
		if (((int*)bink)[2] == ((int*)bink)[3])
			break;
		BinkNextFrame(bink);
	}
	if (fclose(out)) {
		if (!ret) {
			printf("write error\n");
			ret = 1;
		}
	}
	if (!ret)
		printf("ok\n");
	free(pcm);
	BinkCloseTrack(track);
	BinkClose(bink);
	FreeLibrary(bink2w32);
	return ret;
}