diff --git a/main.cc b/main.cc
index 2a2b25c..210d5b4 100644
--- a/main.cc
+++ b/main.cc
@@ -12,6 +12,9 @@
 #include "audioDecoder.h"
 using std::cout;
 
+constexpr int SCREEN_WIDTH = 640;
+constexpr int SCREEN_HEIGHT = 480;
+
 struct OpenglVideoParam
 {
 	SDL_GLContext glContext;
@@ -19,17 +22,20 @@ struct OpenglVideoParam
 	unsigned int texs[3];
 };
 
-int InitAudio(const char* targetFilePath, MediaParam& param)
+int InitAudio(SDL_Window* window, SDL_Renderer* renderer, const char* targetFilePath, MediaParam& param)
 {
 	InitDecoder(targetFilePath, param);
+	window = SDL_CreateWindow("mp", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);
+	renderer= SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
 	std::jthread(RequestAudioPacket, std::ref(param)).detach();
 	SDL_AudioSpec des;
 	des.freq = param.audioParam.codecCtx->sample_rate;
-	des.channels = param.audioParam.codecCtx->channels;
+	des.channels = param.audioParam.codecCtx->ch_layout.nb_channels;
 	des.format = AUDIO_S16SYS;
 	des.samples = 1024;
 	des.silence = 0;
-	des.userdata = &(param.audioParam);
+	std::tuple<SDL_Window*, SDL_Renderer*, AudioParam*>* callbackParam = new std::tuple{window, renderer, &(param.audioParam)};
+	des.userdata = callbackParam;
 	des.callback = audioCallback;
 	if (SDL_OpenAudio(&des, nullptr) < 0)
 	{
@@ -221,7 +227,7 @@ int main(int argc, char** argv)
 	}
 	case FileType::AUDIO:
 	{
-		InitAudio(targetFilepath, mediaParam);
+		InitAudio(window, renderer, targetFilepath, mediaParam);
 		break;
 	}
 	case FileType::ERRORTYPE:
diff --git a/src/audioDecoder.cc b/src/audioDecoder.cc
index 2b84f59..273950b 100644
--- a/src/audioDecoder.cc
+++ b/src/audioDecoder.cc
@@ -3,13 +3,14 @@
 #include <iostream>
 #include <SDL2/SDL_audio.h>
 #include <SDL2/SDL_stdinc.h>
+#include <SDL2/SDL.h>
 
 extern "C" {
 #include "libswresample/swresample.h"
 #include "fftw3.h"
 }
 
-int RequestAudioFrame(AudioParam& param, uint8_t* audioBuffer, int bufSize)
+int RequestAudioFrame(AudioParam& param, uint8_t* audioBuffer, int bufSize, SDL_Window* window, SDL_Renderer* renderer)
 {
 	AVFrame* frame = av_frame_alloc();
 	int dataSize = 0;
@@ -69,19 +70,41 @@ int RequestAudioFrame(AudioParam& param, uint8_t* audioBuffer, int bufSize)
 	const uint64_t dstNbSamples = av_rescale_rnd(swr_get_delay(swrCtx, frame->sample_rate) + frame->nb_samples, frame->sample_rate, frame->sample_rate, static_cast<AVRounding>(1));
 	const int nb = swr_convert(swrCtx, &audioBuffer, static_cast<int>(dstNbSamples), const_cast<const uint8_t**>(frame->data), frame->nb_samples);
 	dataSize = frame->ch_layout.nb_channels * nb * av_get_bytes_per_sample(dstFormat);
+
+	//render wave
+	int nbSamples = frame->nb_samples;
+	fftw_complex* in = static_cast<fftw_complex*>(fftw_malloc(sizeof(fftw_complex) * nbSamples));
+	fftw_complex* out = static_cast<fftw_complex*>(fftw_malloc(sizeof(fftw_complex) * nbSamples));
+
+	for(int i= 0; i < nbSamples; i++) {
+		in[i][0] = frame->data[0][i];
+		in[i][1] = 0;
+	}
+
+	fftw_plan p = fftw_plan_dft_1d(nbSamples, in, out, FFTW_FORWARD, FFTW_ESTIMATE);
+	fftw_execute(p);
+	fftw_destroy_plan(p);
+	//TODO: render wave
+
+	SDL_SetRenderDrawColor(renderer, 0x00, 0x00, 0x00, 0xff);
+	SDL_RenderClear(renderer);
+	SDL_SetRenderDrawColor(renderer, 0xff, 0xff, 0xff, 0xff);
+	SDL_RenderDrawLine(renderer, 0, 0, 300, 300);
+	SDL_RenderPresent(renderer);
 	av_frame_free(&frame);
 	swr_free(&swrCtx);
 	return dataSize;
 }
 
 void audioCallback(void* userdata, uint8_t* stream, int len) {
-	AudioParam* param = static_cast<AudioParam*>(userdata);
+	const auto callbackParam = *static_cast<std::tuple<SDL_Window*, SDL_Renderer*, AudioParam*>*>(userdata);
+	const auto param = std::get<2>(callbackParam);
 	SDL_memset(stream, 0, len);
 	while (len > 0)
 	{
 		if (param->bufferIndex >= param->bufferSize)
 		{
-			const int audioSize = RequestAudioFrame(*param, param->buffer, sizeof(param->buffer));
+			const int audioSize = RequestAudioFrame(*param, param->buffer, sizeof(param->buffer), std::get<0>(callbackParam), std::get<1>(callbackParam));
 			if (audioSize < 0)
 			{
 				param->bufferSize = 0;