Vplayer.c

//
//		The following information is based on :
//		http://dranger.com/ffmpeg/tutorial01.html
//

#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavformat/avio.h>
#include <libswscale/swscale.h>
#include <libavutil/avstring.h>
#include <SDL/SDL.h>
#include <SDL/SDL_thread.h>
#ifdef __MINGW32__
#undef main /* Prevents SDL from overriding main() */
#endif
#include <stdio.h>
#include <math.h>
#define MAX_CHANNELS 3
#define SDL_AUDIO_BUFFER_SIZE 1024
#define MAX_AUDIOQ_SIZE (5 * 16 * 1024)
#define MAX_VIDEOQ_SIZE (5 * 256 * 1024)
#define AV_SYNC_THRESHOLD 0.01
#define AV_NOSYNC_THRESHOLD 10.0
#define SAMPLE_CORRECTION_PERCENT_MAX 10
#define AUDIO_DIFF_AVG_NB 20
#define FF_ALLOC_EVENT   (SDL_USEREVENT)
#define FF_REFRESH_EVENT (SDL_USEREVENT + 1)
#define FF_QUIT_EVENT (SDL_USEREVENT + 2)
#define VIDEO_PICTURE_QUEUE_SIZE 1
#define DEFAULT_AV_SYNC_TYPE AV_SYNC_VIDEO_MASTER

//extern URLProtocol e2URLProtocol;


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

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

typedef struct VideoState{
	int videoIndex, color_req, seek_req, seek_flag;
	int videoStream, audioStream;
	int av_sync_type;
	int audio_pkt_size, audio_hw_buf_size;
	int64_t seek_pos;
	int64_t external_clock_time;
	double external_clock, audio_clock; 
	AVFormatContext *pFormatCtx;
	AVStream *audio_st;
	PacketQueue audioq;	// Struct PacketQueue defined above
	uint8_t audio_buf[(AVCODEC_MAX_AUDIO_FRAME_SIZE * 3) / 2];
	unsigned int audio_buf_size,  audio_buf_index;
	AVPacket audio_pkt;
	uint8_t *audio_pkt_data;
	AVFrame audio_frame;
	AVStream *video_st;
	PacketQueue videoq;
	double audio_diff_cum, audio_diff_avg_coef, audio_diff_threshold; 
	int audio_diff_avg_count;
	double frame_timer, frame_last_pts, frame_last_delay;
	double video_current_pts; ///<current displayed pts (different from video_clock if frame fifos are used)
	int64_t video_current_pts_time; ///<time (av_gettime) at which we updated video_current_pts - used to have running video pts
	double video_clock; ///<pts of last decoded frame / predicted pts of next decoded frame
	VideoPicture pictq[VIDEO_PICTURE_QUEUE_SIZE];
	int pictq_size, pictq_rindex, pictq_windex;
	SDL_mutex *pictq_mutex;
	SDL_cond *pictq_cond;
	SDL_Thread *parse_tid;
	SDL_Thread *video_tid;
	AVIOContext *io_ctx;
	struct SwsContext *sws_ctx;
	struct SwsContext *sws_ctxRGB;
	char filename[1024];
	int quit;
	SDL_AudioSpec want_spec;
} VideoState;

enum{
	AV_SYNC_AUDIO_MASTER, AV_SYNC_VIDEO_MASTER, AV_SYNC_EXTERNAL_MASTER,
};

// global variables
int global_videoIndex = 0;
int global_audioIndex = 0;
SDL_Surface *screen[MAX_CHANNELS];		// global array of screens - size = number of channels
VideoState *global_video_state[MAX_CHANNELS];	// global array of video state - size = number of channels
SDL_mutex *global_mutex_lock;
SDL_cond *global_cond;
AVPacket f_pkt;


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) && (pkt != &f_pkt)){
		return -1;
	}
	pkt1 = 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 void packet_queue_f (PacketQueue *q){
	AVPacketList *pkt, *pkt2;
	SDL_LockMutex(q->mutex);

	pkt=q->first_pkt;
	while(pkt != NULL){
		pkt2 = pkt->next;
		av_free_packet(&pkt->pkt);
		av_freep(&pkt);
		pkt=pkt2;
	}
	q->last_pkt = NULL;
	q->first_pkt = NULL;
	q->size = 0;
	q->nb_packets = 0;
	SDL_UnlockMutex(q->mutex);
}


static int packet_queue_get(PacketQueue *q, AVPacket *pkt, int block, VideoState* is){
	AVPacketList *pkt1;
	int ret;
	SDL_LockMutex(q->mutex);

	for (;;){
		if (is->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;
}


double get_audio_clock(VideoState *is){
	double pts;
	int hw_buf_size, bytes_per_sec, n;

	pts = is->audio_clock; 
	hw_buf_size = is->audio_buf_size - is->audio_buf_index;
	bytes_per_sec = 0;
	n = is->audio_st->codec->channels * 2;
	if (is->audio_st){
		bytes_per_sec = is->audio_st->codec->sample_rate * n;
	}
	if (bytes_per_sec){
		pts -= (double) hw_buf_size / bytes_per_sec;
	}
	return pts;
}


double get_video_clock(VideoState *is){
	double delta;
	delta = (av_gettime() - is->video_current_pts_time) / 1000000.0;
	return is->video_current_pts + delta;
}


double get_external_clock(VideoState *is){
	return av_gettime() / 1000000.0;
}


double get_master_clock(VideoState *is){
	if (is->av_sync_type == AV_SYNC_VIDEO_MASTER){
		return get_video_clock(is);
	}else if (is->av_sync_type == AV_SYNC_AUDIO_MASTER){
		return get_audio_clock(is);
	}else{
		return get_external_clock(is);
	}
}


/* Add or subtract samples to get a better sync, return new audio buffer size */
int synchronize_audio(VideoState *is, short *samples, int samples_size,double pts){
	int n;
	double ref_clock;

	n = 2 * is->audio_st->codec->channels;
	if (is->av_sync_type != AV_SYNC_AUDIO_MASTER){
		double diff, avg_diff;
		int wanted_size, min_size, max_size;
		ref_clock = get_master_clock(is);
		diff = get_audio_clock(is) - ref_clock;
		if (diff < AV_NOSYNC_THRESHOLD){
			// accumulate the diffs
			is->audio_diff_cum = diff+ is->audio_diff_avg_coef * is->audio_diff_cum;
			if (is->audio_diff_avg_count < AUDIO_DIFF_AVG_NB){
				is->audio_diff_avg_count++;
			}else{
				avg_diff = is->audio_diff_cum * (1.0 - is->audio_diff_avg_coef);
				if (fabs(avg_diff) >= is->audio_diff_threshold){
				wanted_size = samples_size+ ((int) (diff * is->audio_st->codec->sample_rate)* n);
				min_size = samples_size* ((100 - SAMPLE_CORRECTION_PERCENT_MAX) / 100);
				max_size = samples_size* ((100 + SAMPLE_CORRECTION_PERCENT_MAX) / 100);
					if (wanted_size < min_size){
						wanted_size = min_size;
					}else if(wanted_size > max_size){
						wanted_size = max_size;
					}
					if (wanted_size < samples_size){
						samples_size = wanted_size;
					}else if(wanted_size > samples_size){
						uint8_t *samples_end, *q;
						int nb;
						/* add samples by copying final sample*/
						nb = (samples_size - wanted_size);
						samples_end = (uint8_t *) samples + samples_size - n;
						q = samples_end + n;
				    	while (nb > 0) {
						memcpy(q, samples_end, n);
						q += n;
						nb -= n;
						}
					samples_size = wanted_size;
					}
				}
			}
		}else{
			is->audio_diff_avg_count = 0;
			is->audio_diff_cum = 0;
		}
	}
	return samples_size;
}


int audio_decode_frame(VideoState *is, double *pts_ptr){

	int len1, data_size = 0, n;
	AVPacket *pkt = &is->audio_pkt;
	double pts;

	for (;;){
		while (is->audio_pkt_size > 0){
			int got_frame = 0;
			len1 = avcodec_decode_audio4(is->audio_st->codec, &is->audio_frame,&got_frame, pkt);
			if (len1 < 0){
				is->audio_pkt_size = 0;
				break;
			}
			if (got_frame){
				//data_size = is->audio_frame.linesize[0];
				data_size = av_samples_get_buffer_size(NULL,
				is->audio_st->codec->channels,
				is->audio_frame.nb_samples,
				is->audio_st->codec->sample_fmt, 1);
				memcpy(is->audio_buf, is->audio_frame.data[0], data_size);
			}
			is->audio_pkt_data += len1;
			is->audio_pkt_size -= len1;
			if (data_size <= 0) {
				/* No data yet, get more frames */
				continue;
			}
			pts = is->audio_clock;
			*pts_ptr = pts;
			n = 2 * is->audio_st->codec->channels;
			is->audio_clock += (double) data_size/(double) (n * is->audio_st->codec->sample_rate);

			/* We have data, return it and come back for more later */
			return data_size;
		}
		if (pkt->data){
			av_free_packet(pkt);
		}
		if (is->quit) {
			return -1;
		}
		/* next packet */
		if (packet_queue_get(&is->audioq, pkt, 1, is) < 0){
			return -1;
		}
		if (pkt->data == f_pkt.data){
			avcodec_flush_buffers(is->audio_st->codec);
			continue;	
		}
		is->audio_pkt_data = pkt->data;
		is->audio_pkt_size = pkt->size;

		/* if update, update the audio clock w/pts */
		if (pkt->pts != AV_NOPTS_VALUE){
			is->audio_clock = av_q2d(is->audio_st->time_base) * pkt->pts;
		}
	}
	return 0;	
}


void audio_callback(void *userdata, Uint8 *stream, int len){
	//VideoState *is = (VideoState *) userdata;
	SDL_LockMutex(global_mutex_lock);
	VideoState *is = global_video_state[global_audioIndex];
	SDL_UnlockMutex(global_mutex_lock);
	int len1, audio_size;
	double pts;

	while (len > 0){
		if (is->audio_buf_index >= is->audio_buf_size){
			/* We have already sent all our data; get more */
			audio_size = audio_decode_frame(is, &pts);
			if (audio_size < 0){
				/* If error, output silence */
				is->audio_buf_size = 1024;
				memset(is->audio_buf, 0, is->audio_buf_size);
			}else{
				audio_size = synchronize_audio(is, (int16_t *) is->audio_buf,audio_size, pts);
				is->audio_buf_size = audio_size;
			}
			is->audio_buf_index = 0;
		}
		len1 = is->audio_buf_size - is->audio_buf_index;
		if (len1 > len){
			len1 = len;
		}
		memcpy(stream, (uint8_t *) is->audio_buf + is->audio_buf_index, len1);
		len -= len1;
		stream += len1;
		is->audio_buf_index += len1;
	}
}


static Uint32 sdl_refresh_timer_cb(Uint32 interval, void *opaque){
	SDL_Event event;
	event.type = FF_REFRESH_EVENT;
	event.user.data1 = opaque;
	SDL_PushEvent(&event);
	return 0; /* 0 means stop timer */
}


		/* schedule a video refresh in 'delay' ms */
static void schedule_refresh(VideoState *is, int delay){
	SDL_AddTimer(delay, sdl_refresh_timer_cb, is);
}


void video_display(VideoState *is){
	SDL_Rect rect;
	VideoPicture *vp;
	float aspect_ratio;
	int w, h, x, y;

	vp = &is->pictq[is->pictq_rindex];
	if (vp->bmp){
		if (is->video_st->codec->sample_aspect_ratio.num == 0){
			aspect_ratio = 0;
		}else{
			aspect_ratio = av_q2d(is->video_st->codec->sample_aspect_ratio)* is->video_st->codec->width / is->video_st->codec->height;
		}
		if (aspect_ratio <= 0.0){
			aspect_ratio = (float) is->video_st->codec->width/ (float) is->video_st->codec->height;
		}
		h = screen[is->videoIndex]->h;
		w = ((int) rint(h * aspect_ratio)) & -3;
		if (w > screen[is->videoIndex]->w){
			w = screen[is->videoIndex]->w;
			h = ((int) rint(w / aspect_ratio)) & -3;
		}
		x = (screen[is->videoIndex]->w - w) / 2;
		y = (screen[is->videoIndex]->h - h) / 2;

		rect.x = x;
		rect.y = y;
		rect.w = w;
		rect.h = h;
		SDL_LockMutex(global_mutex_lock);
		if(is->videoIndex == global_videoIndex){
	    	SDL_DisplayYUVOverlay(vp->bmp, &rect);
		}
		SDL_UnlockMutex(global_mutex_lock);
	}
}


void video_refresh_timer(void *userdata){
	VideoState *is = (VideoState *) userdata;
	VideoPicture *vp;
	double actual_delay, delay, sync_threshold, ref_clock, diff;

	if (is->video_st){
		if (is->pictq_size == 0){
			schedule_refresh(is, 1);
		}else{
			vp = &is->pictq[is->pictq_rindex];
			is->video_current_pts = vp->pts;
			is->video_current_pts_time = av_gettime();
			delay = vp->pts - is->frame_last_pts; /* the pts from last time */
			if (delay <= 0 || delay >= 1.0){
				/* if incorrect delay, use previous one */
				delay = is->frame_last_delay;
			}
			/* save for next time */
			is->frame_last_delay = delay;
			is->frame_last_pts = vp->pts;

			/* update delay to sync to audio */
			ref_clock = get_audio_clock(is);
			diff = vp->pts - ref_clock;

			/* update delay to sync to audio if not master source */
			if (is->av_sync_type != AV_SYNC_VIDEO_MASTER) {
				ref_clock = get_master_clock(is);
				diff = vp->pts - ref_clock;

				/* Skip or repeat the frame. Take delay into account
				FFPlay still doesn't "know if this is the best guess." */
				sync_threshold =(delay > AV_SYNC_THRESHOLD) ? delay : AV_SYNC_THRESHOLD;
			if (fabs(diff) < AV_NOSYNC_THRESHOLD){
				if (diff <= -sync_threshold) {
					delay = 0;
				}else if (diff >= sync_threshold){
					delay = 2 * delay;
				}
			}
		}
		is->frame_timer += delay;
		/* computer the REAL delay */
		actual_delay = is->frame_timer - (av_gettime() / 1000000.0);
		if (actual_delay < 0.010){
			/* Really it should skip the picture instead */
			actual_delay = 0.010;
		}
		schedule_refresh(is, (int) (actual_delay * 1000 + 0.5));

		/* show the picture! */
		video_display(is);

		/* update queue for next picture! */
		if (++is->pictq_rindex == VIDEO_PICTURE_QUEUE_SIZE){
			is->pictq_rindex = 0;
		}
		SDL_LockMutex(is->pictq_mutex);
		is->pictq_size--;
		SDL_CondSignal(is->pictq_cond);
		SDL_UnlockMutex(is->pictq_mutex);
	}
	}else{
		schedule_refresh(is, 100);
	}
} 


void alloc_picture(void *userdata){
	VideoState *is = (VideoState *) userdata;
	VideoPicture *vp;

	vp = &is->pictq[is->pictq_windex];
	if (vp->bmp){
		// we already have one make another, bigger/smaller
		SDL_FreeYUVOverlay(vp->bmp);
	}
	// Allocate a place to put our YUV image on that screen
	vp->bmp = SDL_CreateYUVOverlay(is->video_st->codec->width,is->video_st->codec->height, SDL_YV12_OVERLAY, screen[is->videoIndex]);
	vp->width = is->video_st->codec->width;
	vp->height = is->video_st->codec->height;

	SDL_LockMutex(is->pictq_mutex);
	vp->allocated = 1;
	SDL_CondSignal(is->pictq_cond);
	SDL_UnlockMutex(is->pictq_mutex);
}


int queue_picture(VideoState *is, AVFrame *pFrame,AVFrame *pFrameRGB, double pts){
	VideoPicture *vp;
	AVPicture pict;
	int k;
	

	/* wait until we have space for a new pic */
	SDL_LockMutex(is->pictq_mutex);
	while (is->pictq_size >= VIDEO_PICTURE_QUEUE_SIZE && !is->quit){
		SDL_CondWait(is->pictq_cond, is->pictq_mutex);
	}
	SDL_UnlockMutex(is->pictq_mutex);

	if (is->quit){
		return -1;
	}
	// windex is set to 0 initially
	vp = &is->pictq[is->pictq_windex];
	/* allocate or resize the buffer! */
	if (!vp->bmp || vp->width != is->video_st->codec->width || vp->height != is->video_st->codec->height){
		SDL_Event event;
		vp->allocated = 0;
		/* we have to do it in the main thread */
		event.type = FF_ALLOC_EVENT;
		event.user.data1 = is;
		SDL_PushEvent(&event);

		/* wait until we have a picture allocated */
		SDL_LockMutex(is->pictq_mutex);
		while (!vp->allocated && !is->quit){
			SDL_CondWait(is->pictq_cond, is->pictq_mutex);
		}
		SDL_UnlockMutex(is->pictq_mutex);
		if (is->quit){
			return -1;
		}
	}
	/* We have a place to put our picture on the queue */
	/* If we are skipping a frame, do we set this to null
	but still return vp->allocated = 1? */
	if (vp->bmp){
		// Convert the image into YUV format that SDL uses
	    sws_scale(is->sws_ctxRGB,(const uint8_t * const *) pFrame->data,pFrame->linesize, 0, is->video_st->codec->height,pFrameRGB->data, pFrameRGB->linesize);
		int videoSize = (is->video_st->codec->height) * (is->video_st->codec->width);
		if(is->color_req=='b'){
			for (k=0; k<videoSize; ++k) {
				pFrameRGB->data[0][3*k]='\0';
				pFrameRGB->data[0][3*k+1]='\0';
			}
		}else if(is->color_req=='r'){
			for (k=0; k<videoSize; ++k) {
				pFrameRGB->data[0][3*k+1]='\0';
				pFrameRGB->data[0][3*k+2]='\0';
			}
		}else if(is->color_req=='g'){
			for (k=0; k<videoSize; ++k) {
				pFrameRGB->data[0][3*k]='\0';
				pFrameRGB->data[0][3*k+2]='\0';
			}
		}		  
    	SDL_LockYUVOverlay(vp->bmp);
		//dst_pix_fmt = PIX_FMT_YUV420P;
		/* point pict at the queue */
		pict.data[0] = vp->bmp->pixels[0];
		pict.data[1] = vp->bmp->pixels[2];
		pict.data[2] = vp->bmp->pixels[1];

		pict.linesize[0] = vp->bmp->pitches[0];
		pict.linesize[1] = vp->bmp->pitches[2];
		pict.linesize[2] = vp->bmp->pitches[1];
				
		sws_scale(is->sws_ctx, (const uint8_t * const *) pFrameRGB->data,
		pFrameRGB->linesize, 0, is->video_st->codec->height, pict.data,
		pict.linesize);
	
		if(is->color_req=='w'){		// Change color to black & white
			memset(pict.data[1],128, 480*240);
			memset(pict.data[2],128, 480*240);
		}
		SDL_UnlockYUVOverlay(vp->bmp);
		vp->pts = pts;
		/* now we inform our display thread that we have a pic ready */
		if (++is->pictq_windex == VIDEO_PICTURE_QUEUE_SIZE){
			is->pictq_windex = 0;
		}
		SDL_LockMutex(is->pictq_mutex);
		is->pictq_size++;
		SDL_UnlockMutex(is->pictq_mutex);
	}
	return 0;
}


double synchronize_video(VideoState *is, AVFrame *src_frame, double pts){
	double frame_delay;

	if (pts != 0){
		/* if we have pts, set video clock to it */
		is->video_clock = pts;
	}else{
		/* if we aren't given a pts, set it to the clock */
		pts = is->video_clock;
	}
	/* update the video clock */
	frame_delay = av_q2d(is->video_st->codec->time_base);
	/* if we are repeating a frame, adjust clock accordingly */
	frame_delay += src_frame->repeat_pict * (frame_delay * 0.5);
	is->video_clock += frame_delay;
	return pts;
}


uint64_t global_video_pkt_pts = AV_NOPTS_VALUE;

		/* These are called whenever we allocate a frame
		* buffer. We use this to store the global_pts in
		* a frame at the time it is allocated.
		*/


int our_get_buffer(struct AVCodecContext *c, AVFrame *pic){
	int ret = avcodec_default_get_buffer(c, pic);
	uint64_t *pts = 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);
}


int video_thread(void *arg){
	VideoState *is = (VideoState *) arg;
	AVPacket pkt1, *packet = &pkt1;
	int frameFinished;
	AVFrame *pFrame;
	AVFrame *pFrameRGB;
	double pts;
	int numBytes;
	uint8_t *buffer;
		
	
	// Allocate an AVFrame structure
	pFrameRGB = avcodec_alloc_frame();
	if (pFrameRGB == NULL){
		return -1;
	}
	// Determine required buffer size and allocate buffer
	numBytes = avpicture_get_size(PIX_FMT_RGB24, is->video_st->codec->width, is->video_st->codec->height);
    buffer = (uint8_t *) av_malloc(numBytes * sizeof(uint8_t));

	// Assign appropriate parts of buffer to image planes in pFrameRGB
	// Note that pFrameRGB is an AVFrame, but AVFrame is a superset
	// of AVPicture
	avpicture_fill((AVPicture *) pFrameRGB, buffer, PIX_FMT_RGB24, is->video_st->codec->width, is->video_st->codec->height);
	
	pFrame = avcodec_alloc_frame();
	for (;;){
		if (packet_queue_get(&is->videoq, packet, 1, is) < 0){
			// means we quit getting packets
			break;
		}
		if (packet->data == f_pkt.data){
			avcodec_flush_buffers(is->video_st->codec);
			continue;
		}
		pts = 0;
		// Save global pts to be stored in pFrame in first call
		global_video_pkt_pts = packet->pts;
		// Decode video frame
		//len1 =
		avcodec_decode_video2(is->video_st->codec, pFrame, &frameFinished,packet);
		if (packet->dts == AV_NOPTS_VALUE && pFrame->opaque && *(uint64_t*) pFrame->opaque != AV_NOPTS_VALUE){
			pts = *(uint64_t *) pFrame->opaque;
		}else if (packet->dts != AV_NOPTS_VALUE){
			pts = packet->dts;
		}else{
			pts = 0;
		}
		pts *= av_q2d(is->video_st->time_base);
		// Did we get a video frame?
		if (frameFinished){
			pts = synchronize_video(is, pFrame,pts);
			if (queue_picture(is, pFrame,pFrameRGB, pts) < 0){
    			break;
    		}
		}
	   	av_free_packet(packet);
	}
	av_free(pFrame);
	return 0;
}


int stream_component_open(VideoState *is, int stream_index){
	AVFormatContext *pFormatCtx = is->pFormatCtx;
	AVCodecContext *codecCtx;
	AVCodec *codec;
	SDL_AudioSpec wanted_spec, spec;

	if (stream_index < 0 || stream_index >= pFormatCtx->nb_streams){
		return -1;
	}
	// Get a pointer to the codec context for the video stream
	codecCtx = pFormatCtx->streams[stream_index]->codec;

	if (codecCtx->codec_type == AVMEDIA_TYPE_AUDIO){
		// Set audio settings from codec info
		wanted_spec.freq = codecCtx->sample_rate;
		wanted_spec.format = AUDIO_S16SYS;
		wanted_spec.channels = codecCtx->channels;
		wanted_spec.silence = 0;
		wanted_spec.samples = SDL_AUDIO_BUFFER_SIZE;
		wanted_spec.callback = audio_callback;
		wanted_spec.userdata = is;

		is->want_spec = wanted_spec; 	// check it!
		SDL_LockMutex(global_mutex_lock);
		if(is->videoIndex == global_videoIndex){
			if (SDL_OpenAudio(&wanted_spec, &spec) < 0){
				fprintf(stderr, "SDL_OpenAudio: %s\n", SDL_GetError());
				SDL_UnlockMutex(global_mutex_lock);
				return -1;
	  		}
			is->audio_hw_buf_size = spec.size;
		}
		SDL_UnlockMutex(global_mutex_lock);
	}
	codec = avcodec_find_decoder(codecCtx->codec_id);
	if (!codec || (avcodec_open2(codecCtx, codec, NULL) < 0)){ //&optionDict
		fprintf(stderr, "Unsupported codec!\n");
		return -1;
	}

	switch (codecCtx->codec_type){
		case AVMEDIA_TYPE_AUDIO:
			is->audioStream = stream_index;
			is->audio_st = pFormatCtx->streams[stream_index];
			is->audio_buf_size = 0;
			is->audio_buf_index = 0;

			/* averaging filter for audio sync */
			is->audio_diff_avg_coef = exp(log(0.01 / AUDIO_DIFF_AVG_NB));
			is->audio_diff_avg_count = 0;
			/* Correct audio only if larger error than this */
			is->audio_diff_threshold = 2.0 * SDL_AUDIO_BUFFER_SIZE/ codecCtx->sample_rate;

			memset(&is->audio_pkt, 0, sizeof(is->audio_pkt));
			packet_queue_init(&is->audioq);
			SDL_PauseAudio(0);
			break;
		case AVMEDIA_TYPE_VIDEO:
			is->videoStream = stream_index;
			is->video_st = pFormatCtx->streams[stream_index];

			is->sws_ctxRGB = sws_getContext(is->video_st->codec->width,
			is->video_st->codec->height, is->video_st->codec->pix_fmt,
			is->video_st->codec->width, is->video_st->codec->height,
			PIX_FMT_RGB24, SWS_FAST_BILINEAR, NULL, NULL, NULL);

			if (is->sws_ctxRGB == NULL) {
				fprintf(stderr, "Cannot initialize the sws context\n");
				return -1;
			}

			is->sws_ctx = sws_getContext(is->video_st->codec->width,
			is->video_st->codec->height, PIX_FMT_RGB24,
			is->video_st->codec->width, is->video_st->codec->height,
			PIX_FMT_YUV420P, SWS_FAST_BILINEAR, NULL, NULL, NULL);

			is->frame_timer = (double) av_gettime() / 1000000.0;
			is->frame_last_delay = 40e-3;
			is->video_current_pts_time = av_gettime();

			packet_queue_init(&is->videoq);
			is->video_tid = SDL_CreateThread(video_thread, is);
			codecCtx->get_buffer = our_get_buffer;
			codecCtx->release_buffer = our_release_buffer;
			break;
		default:
			break;
	}
	return 0;
}


int decode_interrupt_cb(void *opaque){
	VideoState* is = (VideoState*) opaque;
	return (is && is->quit);
}


int decode_thread(void *arg){

	VideoState *is = (VideoState *) arg;
	AVFormatContext *pFormatCtx = NULL;
	AVPacket pkt1, *packet = &pkt1;
	int video_index = -1;
	int audio_index = -1;
	int i;
	is->videoStream = -1;
	is->audioStream = -1;
	AVDictionary *io_dic = NULL;
	AVIOInterruptCB interupt_cb;
	//global_video_state = is;

	
	interupt_cb.callback = decode_interrupt_cb;		// will interrupt blocking functions if we quit!
	interupt_cb.opaque = is;
	if (avio_open2(&is->io_ctx, is->filename, 0, &interupt_cb, &io_dic)){
		fprintf(stderr, "Cannot open I/O for %s\n", is->filename);
		return -1;
	}
	// Open video file
	if (avformat_open_input(&pFormatCtx, is->filename, NULL, NULL) != 0){
		return -1; // Couldn't open file
	}
	is->pFormatCtx = pFormatCtx;
	// Retrieve stream information
	if (avformat_find_stream_info(pFormatCtx, NULL) < 0){
		return -1; 		// Couldn't find stream information
	}	
	av_dump_format(pFormatCtx, 0, is->filename, 0);		// Dump information about file onto standard error

	// Find the first video stream
	for (i = 0; i < pFormatCtx->nb_streams; i++){
		if (pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO && video_index < 0){
			video_index = i;
		}
		if (pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_AUDIO && audio_index < 0){
			audio_index = i;
		}
	}
	if (audio_index >= 0){
		stream_component_open(is, audio_index);
	}
	if (video_index >= 0){
		stream_component_open(is, video_index);
	}
	if (is->videoStream < 0 || is->audioStream < 0){
		fprintf(stderr, "%s: could not open codecs\n", is->filename);
		goto fail;
	}

	// main decode loop
	for (;;) {
		if (is->quit){
		break;
	}
	// seek stuff goes here
	if(is->seek_req){
		int str_index = -1;
		int64_t seek_trgt = is->seek_pos;
		if (is->videoStream >= 0 ){
			str_index = is->videoStream;
		}else if (is->audioStream >= 0){
			str_index = is->audioStream;
		}
		if (str_index >= 0){
			seek_trgt = av_rescale_q(seek_trgt, AV_TIME_BASE_Q, pFormatCtx->streams[str_index]->time_base);
		}
		if(av_seek_frame(is->pFormatCtx, str_index, seek_trgt, is->seek_flag) < 0 ){
			fprintf(stderr , "%s : seeking error\n", is->pFormatCtx->filename);
		}else{
			if (is->audioStream >= 0){
				packet_queue_f(&is->audioq);
				packet_queue_put(&is->audioq,&f_pkt);
			}
			if (is->videoStream >= 0){
				packet_queue_f(&is->videoq);
				packet_queue_put(&is->videoq,&f_pkt);
			}
		}
		is->seek_req = 0 ;
	}
	/*if (is->audioq.size > MAX_AUDIOQ_SIZE || is->videoq.size > MAX_VIDEOQ_SIZE){
		SDL_Delay(10);
		continue;
	}		// !!!! maybe need to remove this func !!! ^^^*/
	if (av_read_frame(is->pFormatCtx, packet) < 0){
	    if (is->pFormatCtx->pb->error == 0) {
			SDL_Delay(100); /* no error; wait for user input */
		  	continue;
		} else {
			break;
		}
	}
	// Is this a packet from the video stream?
	if (packet->stream_index == is->videoStream){
		packet_queue_put(&is->videoq, packet);
	} else if (packet->stream_index == is->audioStream){
		packet_queue_put(&is->audioq, packet);
	} else {
		av_free_packet(packet);
		}
	}
	/* all done - wait for it */
	while (!is->quit) {
		SDL_Delay(100);
	}

	fail:{
		SDL_Event event;
		event.type = FF_QUIT_EVENT;
		event.user.data1 = is;
		SDL_PushEvent(&event);
	}
	return 0;
}


void stream_seek(VideoState *is, int64_t pos, int rel){

	if(!is->seek_req){
		is->seek_pos = pos;
		is->seek_flag = rel < 0 ? AVSEEK_FLAG_BACKWARD : 0;
		is->seek_req = 1;
	}
}


void change_audchannel (int next){
	SDL_LockMutex(global_mutex_lock);
	global_audioIndex = next -1;
	SDL_UnlockMutex(global_mutex_lock);
}

void change_vidchannel (int next){
	SDL_LockMutex(global_mutex_lock);
	global_videoIndex = next -1;
	SDL_UnlockMutex(global_mutex_lock);
}

void change_channel (int next){
	SDL_LockMutex(global_mutex_lock);
	global_audioIndex = next -1;
	global_videoIndex = next -1;
	SDL_UnlockMutex(global_mutex_lock);
}

int main(int argc, char *argv[]) {

	SDL_Event event;
	VideoState *is;
	int i;
	puts("start");
	global_mutex_lock = SDL_CreateMutex();

	is = av_mallocz(sizeof(VideoState));
	if (argc < 2){
		fprintf(stderr, "Usage: test <file>\n");
		exit(1);
	}
		
	av_register_all();		// Register all formats and codecs
	puts("avregister");
	//if (av_register_protocol(&e2URLProtocol) < 0){
	//	printf("Error - URL protocol \n");
	//	exit(-1)
	//}
	if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)){
		fprintf(stderr, "Could not initialize SDL - %s\n", SDL_GetError());
		exit(1);
	}
	for(i=0; i<MAX_CHANNELS;i++){
		// Make a screen to put our video
		#ifndef __DARWIN__
		screen[i] = SDL_SetVideoMode(640, 480, 0, 0);
		#else
		screen[i] = SDL_SetVideoMode(640, 480, 24, 0);
		#endif
		if (!screen[i]){
			fprintf(stderr, "SDL: could not set video mode - exiting\n");
			exit(1);
		}
	}
	for(i=0; i<MAX_CHANNELS;i++){
		global_video_state[i] = av_mallocz(sizeof(VideoState));
		global_video_state[i]->videoIndex = i;
		puts("screen created");
		printf("i is: %d\n",i);
		av_strlcpy(global_video_state[i]->filename, argv[i+1], sizeof(global_video_state[i]->filename));
		puts("avstrlcpy");	
		global_video_state[i]->pictq_mutex = SDL_CreateMutex();
		global_video_state[i]->pictq_cond = SDL_CreateCond();
		schedule_refresh(global_video_state[i], 40);
		global_video_state[i]->av_sync_type = DEFAULT_AV_SYNC_TYPE;
		global_video_state[i]->parse_tid = SDL_CreateThread(decode_thread, global_video_state[i]);
		puts("main var created");
		if (!global_video_state[i]->parse_tid) {
			av_free(global_video_state[i]);
			return -1;
		}
	}
	av_init_packet(&f_pkt);
	puts("av_init_packet");
	f_pkt.data = (unsigned char*)"FLUSH";

	for (;;) {
		double inc , pos;
		SDL_WaitEvent(&event);
		switch (event.type) {
			case SDL_KEYDOWN:
				switch (event.key.keysym.sym) {
					case SDLK_LEFT:
						inc = -10.0;
						goto do_seek;
					case SDLK_RIGHT:
						inc = 10.0;
						goto do_seek;
					case SDLK_UP:
						inc = 60.0;
						goto do_seek;
					case SDLK_DOWN:
						inc = -60.0;
						goto do_seek;
					do_seek:
						SDL_LockMutex(global_mutex_lock);
						if (global_video_state[global_videoIndex]){
							pos = get_master_clock(global_video_state[global_videoIndex]);
							pos += inc;
							stream_seek(global_video_state[global_videoIndex],(int64_t)(pos *AV_TIME_BASE),inc);
						}
						SDL_UnlockMutex(global_mutex_lock);
						break;
					case SDLK_b:
						global_video_state[global_videoIndex]->color_req = 'b';
						break;
					case SDLK_r:
						global_video_state[global_videoIndex]->color_req = 'r';
						break;
					case SDLK_g:
						global_video_state[global_videoIndex]->color_req = 'g';
						break;
					case SDLK_w:
						global_video_state[global_videoIndex]->color_req = 'w';
						break;
					case SDLK_n:
						global_video_state[global_videoIndex]->color_req = 'n';
						break;
					case SDLK_1:
						change_channel(1);
						break;
					case SDLK_2:
						change_channel(2);
						break;
					case SDLK_3:
						change_channel(3);
						break;
					case SDLK_4:
						change_vidchannel(1);
						break;
					case SDLK_5:
						change_vidchannel(2);
						break;
					case SDLK_6:
						change_vidchannel(3);
						break;
					case SDLK_7:
						change_audchannel(1);
						break;
					case SDLK_8:
						change_audchannel(2);
						break;
					case SDLK_9:
						change_audchannel(3);
						break;
				default:
					break;
				}
				break;
			case FF_QUIT_EVENT:
				case SDL_QUIT:
					for(i=0; i<MAX_CHANNELS; i++){
						global_video_state[i]->quit = 1;
						SDL_CondSignal(global_video_state[i]->audioq.cond);
						SDL_CondSignal(global_video_state[i]->videoq.cond);
					}
					SDL_Quit();
					exit(0);
					break;
				case FF_ALLOC_EVENT:
					alloc_picture(event.user.data1);
					break;
				case FF_REFRESH_EVENT:
					video_refresh_timer(event.user.data1);
					break;
			default:
				break;
		}
	}
	return 0;

}