SDL播放视频

// PlayVideo.cpp : Defines the entry point for the console application.
//

extern "C"
{
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libswscale/swscale.h>
#include <libswresample/swresample.h>
#include <libavutil/avstring.h>
#include <libavutil/pixfmt.h>
#include <libavutil/log.h>
};
#include <windows.h>
#include <stdio.h>
#include <math.h>
#include <SDL.h>
#include <SDL_thread.h>
#include <SDL_main.h>

#pragma comment(lib, "libmingwex.lib")
#pragma comment(lib, "libgcc.lib")
#pragma comment(lib, "avformat.lib")
#pragma comment(lib, "avutil.lib")
#pragma comment(lib, "avcodec.lib")
#pragma comment(lib, "swresample.lib")
#pragma comment(lib, "swscale.lib")

#pragma comment(lib, "SDL.lib")
#pragma comment(lib, "SDLmain.lib")

//speedloss is decided by scale
//#define PICTURE_W 640
//#define PICTURE_H 352
//#define PICTURE_PW 640
//#define PICTURE_PH 352
//change 100
#define MAX_QUEUE_SIZE     50

#define VIDEO_PICTURE_QUEUE_SIZE 2  

typedef struct VideoPicture_t{
	SDL_Overlay *bmp;
	double pts;
	double duration;
	int width,height;
}VideoPicture;  

struct play_info_t{
	//先注释掉同步
	double audio_clock;//解码时钟
	double audio_current_pts;//当前音频的pts
	double vedio_clock;//解码时钟
	double last_frame_pts;//上一帧的PTS值
	double last_frame_delay;//上一帧的延时
	double frame_timer;  

	AVCodecContext *pVideoCodecCtx;
	AVCodecContext *pAudioCodecCtx;  

	VideoPicture pictq[VIDEO_PICTURE_QUEUE_SIZE];
	int pictq_size, pictq_rindex, pictq_windex;
	SDL_mutex *pictq_mutex;
	SDL_cond *pictq_cond;  

	struct SwrContext *audio_conv;
	struct SwsContext *video_conv;
};  

struct play_info_t g_play_info;  

typedef struct PacketQueue {
	AVPacketList *first_pkt, *last_pkt;
	int nb_packets;
	int size;
	SDL_mutex *mutex;
	SDL_cond *cond;
} PacketQueue;  

PacketQueue audio_queue;
PacketQueue video_queue;
int quit = 0;
SDL_Surface *screen;
SDL_Overlay *bmp;
SDL_Rect rect;  

int global_video_pkt_pts=0;
int our_get_buffer(struct AVCodecContext *c, AVFrame *pic) {
	int ret = avcodec_default_get_buffer(c, pic);
	uint64_t *pts = (uint64_t *)av_malloc(sizeof(uint64_t));
	*pts = global_video_pkt_pts;
	pic->opaque = pts;
	return ret;
}
void our_release_buffer(struct AVCodecContext *c, AVFrame *pic) {
	if(pic) av_freep(&pic->opaque);
	avcodec_default_release_buffer(c, pic);
}  

double get_audio_clock(void)
{
	return g_play_info.audio_current_pts;
} 

double get_video_clock(void)
{
	return g_play_info.vedio_clock;
} 

void picture_queque_init(struct play_info_t *play)
{
	int i;
	play->pictq_cond=SDL_CreateCond();
	play->pictq_mutex=SDL_CreateMutex();
	play->pictq_rindex=play->pictq_windex=0;
	play->pictq_size=0;
	memset(play->pictq,0,sizeof(play->pictq));
	for(i=0;i<VIDEO_PICTURE_QUEUE_SIZE;i++){  //注释掉   g_play_info.pVideoCodecCtx->height
		//play->pictq[i].bmp=SDL_CreateYUVOverlay(PICTURE_W,PICTURE_H,SDL_YUY2_OVERLAY,screen);
		play->pictq[i].bmp=SDL_CreateYUVOverlay(g_play_info.pVideoCodecCtx->width,g_play_info.pVideoCodecCtx->height,SDL_YUY2_OVERLAY,screen);
	}
}  

void picture_queque_destroy(struct play_info_t *play)
{
	int i;
	for(i=0;i<VIDEO_PICTURE_QUEUE_SIZE;i++){
		SDL_FreeYUVOverlay(play->pictq[i].bmp);
	}
}  

void packet_queue_init(PacketQueue *q) {
	memset(q, 0, sizeof(PacketQueue));
	q->mutex = SDL_CreateMutex();
	q->cond = SDL_CreateCond();
}  

int packet_queue_put(PacketQueue *q, AVPacket *pkt) {
	AVPacketList *pkt1;
	if(av_dup_packet(pkt) < 0) {
		return -1;
	}
	pkt1 = (AVPacketList *)av_malloc(sizeof(AVPacketList));
	if (!pkt1)
		return -1;
	pkt1->pkt = *pkt;
	pkt1->next = NULL;
	SDL_LockMutex(q->mutex);
	if (!q->last_pkt)
		q->first_pkt = pkt1;
	else
		q->last_pkt->next = pkt1;
	q->last_pkt = pkt1;
	q->nb_packets++;
	q->size += pkt1->pkt.size;
	SDL_CondSignal(q->cond);
	SDL_UnlockMutex(q->mutex);
	return 0;
}  

static int packet_queue_get(PacketQueue *q, AVPacket *pkt, int block) {
	AVPacketList *pkt1;
	int ret;
	SDL_LockMutex(q->mutex);
	for(;;) {
		if(quit) {
			ret = -1;
			break;
		}
		pkt1 = q->first_pkt;
		if (pkt1) {
			q->first_pkt = pkt1->next;
			if (!q->first_pkt)
				q->last_pkt = NULL;
			q->nb_packets--;
			q->size -= pkt1->pkt.size;
			*pkt = pkt1->pkt;
			av_free(pkt1);
			ret = 1;
			break;
		} else if (!block) {
			ret = 0;
			break;
		} else {
			SDL_CondWait(q->cond, q->mutex);
		}
	}
	SDL_UnlockMutex(q->mutex);
	return ret;
}  

int decode_interrupt_cb(void) {
	return quit;
}  

//计算正确的pts值
double sync_video(struct play_info_t *play,AVFrame* frame,double pts)
{
	double frame_delay;
	if(pts!=0)
		play->vedio_clock=pts;
	else
		pts=play->vedio_clock;
	frame_delay=av_q2d(play->pVideoCodecCtx->time_base);//一帧占用的时间
	frame_delay+=frame->repeat_pict*(frame_delay*0.5);//计算重复帧
	play->vedio_clock+=frame_delay;
	return pts;
}  

int audio_decode_frame(struct play_info_t* play, uint8_t *audio_buf,int buf_size) {
	AVCodecContext *aCodecCtx=play->pAudioCodecCtx;
	AVFrame *pAudioFrame=avcodec_alloc_frame();
	AVPacket pkt,pkt1;
	int frame_finished=0;
	int pkt_pos,pkt_len;
	int src_len=0,dst_len=0,data_size=0;
	float pts=0;
	avcodec_get_frame_defaults(pAudioFrame);  

	uint8_t *out[]={audio_buf};  

	for(;!quit;){
		if(packet_queue_get(&audio_queue, &pkt, 1) < 0) {
			av_free(pAudioFrame);
			return -1;
		}
		pkt1=pkt;
		pkt_pos=0;
		pkt_len=pkt.size;  

		while(pkt_pos<pkt.size && !quit){
			if((src_len=avcodec_decode_audio4(aCodecCtx,pAudioFrame,&frame_finished,&pkt1))<0){
				av_free_packet(&pkt);
				av_free(pAudioFrame);
				return -1;
			}  

		/*	play->audio_clock+=(double)(pAudioFrame->linesize[0])/
				(aCodecCtx->channels*aCodecCtx->sample_rate*av_get_bytes_per_sample(aCodecCtx->sample_fmt));  */
			if(video_queue.nb_packets>= 100 || audio_queue.nb_packets>= 200){  //改写
				//printf("%d---%d\n",video_queue.nb_packets,audio_queue.nb_packets);
				Sleep(20); //  change   10000

			}
			else if(video_queue.nb_packets>= 50 || audio_queue.nb_packets>= 100)
			{
				Sleep(10);

			}

			if(frame_finished){
				const uint8_t **in=(const uint8_t **)pAudioFrame->data;
				int len=swr_convert(play->audio_conv,out,buf_size/aCodecCtx->channels/av_get_bytes_per_sample(AV_SAMPLE_FMT_S16),
					in,pAudioFrame->linesize[0]/aCodecCtx->channels/av_get_bytes_per_sample((AVSampleFormat)pAudioFrame->format));
				len=len*aCodecCtx->channels*av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
				av_free(pAudioFrame);
				av_free_packet(&pkt);
				return len;
			}else{
				if (!pkt1.data && aCodecCtx->codec->capabilities & CODEC_CAP_DELAY){
					break;
				}
			}
			pkt_pos+=src_len;//已经解码的长度
			pkt1.data=pkt.data+pkt_pos;
			pkt1.size=pkt.size-pkt_pos;  

		}
		av_free_packet(&pkt);
	}
	av_free(pAudioFrame);
	return dst_len;
}  

//decode the audio data ,and copy the result to stream
void SDLCALL audio_callback(void *userdata, Uint8 *stream, int len)
{
	struct play_info_t *play=(struct play_info_t*)userdata;
	AVCodecContext *aCodecCtx = play->pAudioCodecCtx;
	int len1, audio_size;
	static uint8_t audio_buf[(AVCODEC_MAX_AUDIO_FRAME_SIZE * 3) / 2];
	static unsigned int audio_buf_size = 0;
	static unsigned int audio_buf_index = 0;
	int bytes_per_sec=2*aCodecCtx->channels*aCodecCtx->sample_rate;  

	while(len > 0 && !quit) {
		if(audio_buf_index >= audio_buf_size) {
			audio_size = audio_decode_frame(play, audio_buf,sizeof(audio_buf));
			if(audio_size < 0) {
				audio_buf_size = 1024;
				memset(audio_buf, 0, audio_buf_size);
			} else {
				audio_buf_size = audio_size;
			}
			audio_buf_index = 0;
		}
		len1 = audio_buf_size - audio_buf_index;  

		if(len1 > len)
			len1 = len;
		memcpy(stream, (uint8_t *)audio_buf + audio_buf_index, len1);
		len -= len1;
		stream += len1;
		audio_buf_index += len1;
	}
	//先注释掉同步,自然播放
	if(audio_buf_size > audio_buf_index){
		play->audio_current_pts=play->audio_clock-((double)(audio_buf_size-audio_buf_index)/(double)bytes_per_sec);
		if(play->audio_current_pts<0)
			play->audio_current_pts=play->audio_clock;
		printf("audio-pts:%f\n",play->audio_current_pts);
	}
}  

int SDLCALL video_decode_callback(void* arg)
{
	printf("---in video decode thread ---\n");
	struct play_info_t* play=(struct play_info_t*)arg;
	AVCodecContext *pVideoCodecCtx=play->pVideoCodecCtx;
	double pts;
	VideoPicture *vp;
	AVPacket pkt;
	int frame_finished;
	AVPicture pict = { { 0 } };
	AVFrame *pVideoFrame=avcodec_alloc_frame();
	if(pVideoFrame==NULL){
		printf("can't alloc video frame!\n");
		return -1;
	}  

	while(!quit){
		if(packet_queue_get(&video_queue, &pkt, 1) < 0) {
			return -1;
		}
		pts = 0;
		// Save global pts to be stored in pFrame in first call
		global_video_pkt_pts = pkt.pts;
		avcodec_decode_video2(pVideoCodecCtx,pVideoFrame,&frame_finished,&pkt);
		if(pkt.dts == AV_NOPTS_VALUE && pVideoFrame->opaque && *(uint64_t*)pVideoFrame->opaque != AV_NOPTS_VALUE){
			pts = *(uint64_t *)pVideoFrame->opaque;
		} else if(pkt.dts!=AV_NOPTS_VALUE){
			pts=pkt.dts;
		}else{
			pts=0;
		}
		pts*=av_q2d(pVideoCodecCtx->time_base);  

		av_free_packet(&pkt);
		if(video_queue.nb_packets>= 100 || audio_queue.nb_packets>= 200){  //改写
			printf("%d---%d\n",video_queue.nb_packets,audio_queue.nb_packets);
			Sleep(20); //  change   10000

		}
		else if(video_queue.nb_packets>= 50 || audio_queue.nb_packets>= 100)
		{
			Sleep(10);

		}
		if(frame_finished){
			SDL_LockMutex(play->pictq_mutex);
			while(play->pictq_size >= VIDEO_PICTURE_QUEUE_SIZE && !quit){
				SDL_CondWait(play->pictq_cond,play->pictq_mutex);
			}
			SDL_UnlockMutex(play->pictq_mutex);
			if(quit)
				goto out;  

			vp=&play->pictq[play->pictq_windex];
			SDL_Overlay *bmp=vp->bmp; //定义
			//序列化帧
			pts=sync_video(&g_play_info,pVideoFrame,pts);
			vp->pts=pts;
			printf("video-pts:%f\n",pts);  

			SDL_LockYUVOverlay(bmp);  //加锁
			pict.data[0]=bmp->pixels[0];
			pict.data[1]=bmp->pixels[2];
			pict.data[2]=bmp->pixels[1];
			pict.linesize[0]=bmp->pitches[0];
			pict.linesize[1]=bmp->pitches[2];
			pict.linesize[2]=bmp->pitches[1];
			sws_scale(play->video_conv,pVideoFrame->data,pVideoFrame->linesize,0,
				pVideoFrame->height,pict.data,pict.linesize);
			SDL_UnlockYUVOverlay(bmp);  

			play->pictq_windex=(play->pictq_windex+1)%VIDEO_PICTURE_QUEUE_SIZE;
			SDL_LockMutex(play->pictq_mutex);
			play->pictq_size++;
			SDL_UnlockMutex(play->pictq_mutex);  

		}
	}
out:
	av_free(pVideoFrame);
	printf("---- exit video_decode_callback ----\n");
	return 0;
}  

void video_image_display(struct play_info_t *play)
{
	double delay,time;
	VideoPicture *vp;
	double diff,sync_threshold;
	if(play->pictq_size>0){
		vp=&play->pictq[play->pictq_rindex];
		delay=vp->pts - play->last_frame_pts;
		if(delay>0 && delay<10){
			play->last_frame_delay=delay;
		}
		delay=play->last_frame_delay;  

		diff=vp->pts-get_audio_clock();
		sync_threshold = FFMAX(0.01, delay);
		if (fabs(diff) < 10) {
			if (diff <= -sync_threshold)
				delay = 0;
			else if (diff >= sync_threshold)
				delay = 2 * delay;
		}  

		time=av_gettime()/1000000.0;
		if(time < play->frame_timer+delay)
			return ;  

		if(delay>0)
			play->frame_timer+=delay;
		play->last_frame_pts=vp->pts;  

		SDL_DisplayYUVOverlay(vp->bmp,&rect);  //显示

		play->pictq_rindex=(play->pictq_rindex+1)%VIDEO_PICTURE_QUEUE_SIZE;  

		SDL_LockMutex(play->pictq_mutex);
		play->pictq_size--;
		SDL_CondSignal(play->pictq_cond);
		SDL_UnlockMutex(play->pictq_mutex);  

	}
}  

int SDLCALL video_show_callback(void* arg)
{
	double delay=80;  
	struct play_info_t *play=(struct play_info_t*)arg;
	while(!quit){
		video_image_display(play);
		Sleep(delay);
	}
	printf("----exit video_show_callback ----\n");
	return 0;
}  

void player_log_callback(void* ptr, int level, const char* fmt, va_list vl)
{
	static int print_prefix = 0;
	static int count;
	char line[1024];
	av_log_format_line(ptr, level, fmt, vl, line, sizeof(line), &print_prefix);
	printf("%s",line);
}  

int main(int argc,char *argv[])
{
	if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)<0){
		printf("Init SDL err!\n");
		return -1;
	}  

	av_log_set_callback(player_log_callback);
	av_register_all();  

	AVFormatContext *pFormatCtx;
	pFormatCtx=avformat_alloc_context();
	argv[1]="test.mp4";
	if(avformat_open_input(&pFormatCtx,argv[1],NULL,NULL)<0){
		printf("avformat_open_input err!\n");
		return -1;
	}  

	if(avformat_find_stream_info(pFormatCtx,NULL)<0){
		printf("avformat_find_stream_info err!\n");
		return -1;
	}  

	//av_dump_format(pFormatCtx,0,argv[1],0);  

	int video_stream=-1,audio_stream=-1,i;
	for(i=0;i<pFormatCtx->nb_streams;i++){
		if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){
			video_stream=i;
		}
		if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO){
			audio_stream=i;
		}
	}
	if(video_stream==-1 || audio_stream==-1){
		printf("not find video or audio stream!\n");
		avformat_close_input(&pFormatCtx);
		return -1;
	}
	g_play_info.pVideoCodecCtx=pFormatCtx->streams[video_stream]->codec;
	g_play_info.pAudioCodecCtx=pFormatCtx->streams[audio_stream]->codec;  

	//find the decoder
	AVCodec *pVideoCodec=avcodec_find_decoder(g_play_info.pVideoCodecCtx->codec_id);
	if(pVideoCodec==NULL){
		printf("not find video decoder!\n");
		avformat_close_input(&pFormatCtx);
		return -1;
	}
	AVCodec *pAudioCodec=avcodec_find_decoder(g_play_info.pAudioCodecCtx->codec_id);
	if(pVideoCodec==NULL){
		printf("not find audio decoder!\n");
		avformat_close_input(&pFormatCtx);
		return -1;
	}
	//open the codec
	if(avcodec_open(g_play_info.pVideoCodecCtx,pVideoCodec)<0){
		printf("can't open the video decoder!\n");
		avformat_close_input(&pFormatCtx);
		return -1;
	}
	if(avcodec_open(g_play_info.pAudioCodecCtx,pAudioCodec)<0){
		printf("can't open the audio decoder!\n");
		avcodec_close(g_play_info.pVideoCodecCtx);
		avformat_close_input(&pFormatCtx);
		return -1;
	}  

	//setup SDL
	screen = SDL_SetVideoMode(g_play_info.pVideoCodecCtx->width, g_play_info.pVideoCodecCtx->height, 0, 0);//设置视频模式参数
	picture_queque_init(&g_play_info);
	packet_queue_init(&video_queue);
	packet_queue_init(&audio_queue);  

	rect.x=0;
	rect.y=0;
	rect.w = g_play_info.pVideoCodecCtx->width;
	rect.h = g_play_info.pVideoCodecCtx->height;  

	//setup the sdl audio
	SDL_AudioSpec sdl_audio;
	int64_t wanted_channel_layout = 0;
	int wanted_nb_channels;
	wanted_channel_layout =
		(g_play_info.pAudioCodecCtx->channel_layout &&
		g_play_info.pAudioCodecCtx->channels == av_get_channel_layout_nb_channels(g_play_info.pAudioCodecCtx->channel_layout)) ? g_play_info.pAudioCodecCtx->channel_layout : av_get_default_channel_layout(g_play_info.pAudioCodecCtx->channels);
	wanted_channel_layout &= ~AV_CH_LAYOUT_STEREO_DOWNMIX;
	wanted_nb_channels = av_get_channel_layout_nb_channels(wanted_channel_layout);
	/* SDL only supports 1, 2, 4 or 6 channels at the moment, so we have to make sure not to request anything else. */
	while (wanted_nb_channels > 0 && (wanted_nb_channels == 3 || wanted_nb_channels == 5 || wanted_nb_channels > 6)) {
		wanted_nb_channels--;
		wanted_channel_layout = av_get_default_channel_layout(wanted_nb_channels);
	}
	sdl_audio.channels=av_get_channel_layout_nb_channels(wanted_channel_layout);
	g_play_info.pAudioCodecCtx->channels=sdl_audio.channels;
	g_play_info.pAudioCodecCtx->channel_layout=wanted_channel_layout;  

	g_play_info.audio_conv=swr_alloc_set_opts(NULL,wanted_channel_layout,AV_SAMPLE_FMT_S16,g_play_info.pAudioCodecCtx->sample_rate,
		wanted_channel_layout,g_play_info.pAudioCodecCtx->sample_fmt,
		g_play_info.pAudioCodecCtx->sample_rate,0,NULL);
	swr_init(g_play_info.audio_conv);  

	sdl_audio.freq=g_play_info.pAudioCodecCtx->sample_rate;
	sdl_audio.format=AUDIO_S16SYS;
	sdl_audio.channels=g_play_info.pAudioCodecCtx->channels;
	sdl_audio.silence=0;
	sdl_audio.samples=1024;
	sdl_audio.callback=audio_callback;//calls when the audio device need more data
	sdl_audio.userdata=&g_play_info;
	if(SDL_OpenAudio(&sdl_audio,NULL)<0){
		printf("can't open audio device!\n");
		goto err_alloc_frame1;
	}
	g_play_info.vedio_clock=0;
	g_play_info.audio_clock=0;
	g_play_info.audio_current_pts=0;
	g_play_info.last_frame_pts=0;
	g_play_info.last_frame_delay=0;
	g_play_info.frame_timer=av_gettime()/1000000.0;
	g_play_info.pVideoCodecCtx->get_buffer=our_get_buffer;
	g_play_info.pVideoCodecCtx->release_buffer=our_release_buffer;  

	SDL_PauseAudio(0); 
	g_play_info.video_conv=sws_getContext(g_play_info.pVideoCodecCtx->width,g_play_info.pVideoCodecCtx->height,
	g_play_info.pVideoCodecCtx->pix_fmt,
	g_play_info.pVideoCodecCtx->width,g_play_info.pVideoCodecCtx->height,PIX_FMT_YUYV422,SWS_POINT,NULL,NULL,NULL);
	SDL_Thread * video_decode_thread=SDL_CreateThread(video_decode_callback,(void*)&g_play_info);  
	SDL_Thread * video_show_thread=SDL_CreateThread(video_show_callback,(void*)&g_play_info);
	SDL_Event sdl_event;
	AVPacket packet;  

	while(!quit){
		SDL_PollEvent(&sdl_event);
		if(sdl_event.type==SDL_QUIT){
			SDL_CondSignal(video_queue.cond);
			SDL_CondSignal(audio_queue.cond);
			quit=1;
			break;
		}
			if(av_read_frame(pFormatCtx,&packet)<0){
			quit=1;
			continue;
		}
		if(packet.stream_ndex==video_stream){
			packet_queue_put(&video_queue,&packet);
			//change
                  Sleep(25);//change
		}else if(packet.stream_index==audio_stream){
			packet_queue_put(&audio_queue,&packet);
			//change
		}else{
			av_free_packet(&packet);
		}  

		//usleep(5000);
	}
	SDL_CloseAudio();
	SDL_CondSignal(g_play_info.pictq_cond);
	SDL_WaitThread(video_decode_thread,NULL);
	SDL_WaitThread(video_show_thread,NULL);
	picture_queque_destroy(&g_play_info);  

	swr_free(&g_play_info.audio_conv);
	sws_freeContext(g_play_info.video_conv);  

	SDL_FreeSurface(screen);
	avcodec_close(g_play_info.pVideoCodecCtx);
	avcodec_close(g_play_info.pAudioCodecCtx);
	avformat_close_input(&pFormatCtx);
	return 0;  

err_alloc_frame1:
	avcodec_close(g_play_info.pAudioCodecCtx);
	avcodec_close(g_play_info.pVideoCodecCtx);
	avformat_close_input(&pFormatCtx);
	return -1;
}