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ffmpeg版本：ffmpeg-20160413-git-0efafc5

#include 
   
    #include 
    
     #include 
     
      extern "C"{#include "libavcodec/avcodec.h"#include "libavformat/avformat.h"#include "libswresample/swresample.h"#include "SDL.h"};#define MAX_AUDIO_FRAME_SIZE 192000 // 1 second of 48khz 32bit audioUint32  audio_len;//音频数据大小Uint8  *audio_pos;//指向音频数据的指针//回调函数void  fill_audio(void *userdata, Uint8 *stream, int len){	//SDL 2.0	SDL_memset(stream, 0, len);	if (audio_len == 0)	{		return;	}	len = (len > audio_len ? audio_len : len);	SDL_MixAudio(stream, audio_pos, len, SDL_MIX_MAXVOLUME);	audio_pos += len;	audio_len -= len;}int main(int argc, char* argv[]){	//FFmpeg	AVFormatContext		*pFormatCtx;	AVCodecContext		*pCodecCtx;	AVCodec				*pCodec;	AVPacket			packet;	AVFrame				*pFrame;	struct SwrContext	*au_convert_ctx;	int					got_picture;	int					audioIndex;		//SDL	uint8_t				*out_buffer;	SDL_AudioSpec		wanted_spec;	int					index = 0;		char filepath[1024] = "";	printf("Usage: player.exe *.mp3\n");	if (argc == 2)	{		strcpy(filepath, argv[1]);	}	else	{		printf("Could not find a audio file\n");		return -1;	}	av_register_all();	pFormatCtx = avformat_alloc_context();		if (avformat_open_input(&pFormatCtx, filepath, NULL, NULL) != 0)	{		printf("Couldn't open input stream.\n");		return -1;	}		if (avformat_find_stream_info(pFormatCtx, NULL) < 0)	{		printf("Couldn't find stream information.\n");		return -1;	}		av_dump_format(pFormatCtx, -1, filepath, 0);		audioIndex = -1;	for (unsigned int i = 0; i < pFormatCtx->nb_streams; i++)	{		//AVStream->codec不推荐使用		if (pFormatCtx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)		{			audioIndex = i;			break;		}	}	if (audioIndex == -1)	{		printf("Didn't find a audio stream.\n");		return -1;	}	//------------------------------------------------	//新版本:分配、填充AVCodecContext	pCodecCtx = avcodec_alloc_context3(NULL);	if (pCodecCtx == NULL)	{		printf("Could not allocate AVCodecContext\n");		return -1;	}	if (avcodec_parameters_to_context(pCodecCtx, pFormatCtx->streams[audioIndex]->codecpar) < 0)	{		printf("Could not initialize AVCodecContext\n");		return -1;	}	//------------------------------------------------	pCodec = avcodec_find_decoder(pCodecCtx->codec_id);	if (pCodec == NULL)	{		printf("Codec not found.\n");		return -1;	}	if (avcodec_open2(pCodecCtx, pCodec, NULL)<0)	{		printf("Could not open codec.\n");		return -1;	}	//Out Audio Param	uint64_t out_channel_layout = AV_CH_LAYOUT_STEREO;	//nb_samples: AAC-1024 MP3-1152	int out_nb_samples = pCodecCtx->frame_size;	AVSampleFormat out_sample_fmt = AV_SAMPLE_FMT_S16;	int out_sample_rate = 44100;	int out_channels = av_get_channel_layout_nb_channels(out_channel_layout);	//Out Buffer Size	int out_buffer_size = av_samples_get_buffer_size(NULL, out_channels, out_nb_samples, out_sample_fmt, 1);	out_buffer = (uint8_t *)av_malloc(MAX_AUDIO_FRAME_SIZE * 2);	pFrame = av_frame_alloc();	//Init	if (SDL_Init(SDL_INIT_AUDIO)) 	{		printf("Could not initialize SDL - %s\n", SDL_GetError());		return -1;	}	//SDL_AudioSpec	wanted_spec.freq = out_sample_rate;	wanted_spec.format = AUDIO_S16SYS;	wanted_spec.channels = out_channels;	wanted_spec.silence = 0;	wanted_spec.samples = out_nb_samples;	wanted_spec.callback = fill_audio;	wanted_spec.userdata = pCodecCtx;	if (SDL_OpenAudio(&wanted_spec, NULL) < 0)	{		printf("can't open audio.\n");		return -1;	}	au_convert_ctx = swr_alloc();	au_convert_ctx = swr_alloc_set_opts(au_convert_ctx, out_channel_layout, out_sample_fmt, out_sample_rate,		pCodecCtx->channel_layout, pCodecCtx->sample_fmt, pCodecCtx->sample_rate, 0, NULL);	swr_init(au_convert_ctx);	//Play	SDL_PauseAudio(0);	while (av_read_frame(pFormatCtx, &packet) >= 0)	{		if (packet.stream_index == audioIndex)		{			if (avcodec_decode_audio4(pCodecCtx, pFrame, &got_picture, &packet) < 0)			{				printf("Error in decoding audio frame.\n");				return -1;			}			if (got_picture)			{				swr_convert(au_convert_ctx, &out_buffer, MAX_AUDIO_FRAME_SIZE, (const uint8_t **)pFrame->data, pFrame->nb_samples);				printf("index:%5d\t pts:%lld\t packet size:%d\n", index, packet.pts, packet.size);				index++;			}			while (audio_len > 0)//Wait until finish			{				SDL_Delay(1);			}			//Audio buffer length			audio_len = out_buffer_size;			audio_pos = (Uint8 *)out_buffer;		}		av_packet_unref(&packet);	}	swr_free(&au_convert_ctx);	SDL_CloseAudio();//Close SDL	SDL_Quit();	av_free(out_buffer);	avcodec_free_context(&pCodecCtx);	avformat_close_input(&pFormatCtx);	return 0;}