FFMPEG教程7_快进和快退(使用2014年新SDK重新整理编译通过）

#include "stdafx.h"
#include <math.h>
#include <Windows.h>

#pragma warning( disable : 4312 )
#pragma warning( disable : 4244 )
#pragma warning( disable : 4311 )

#ifdef  __cplusplus
extern "C" {
#endif
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavutil/avutil.h>
#include <libswscale/swscale.h>
#include <libavutil/avstring.h>

#include <SDL/SDL.h>
#include <SDL/SDL_video.h>      // SDL
#include <SDL/SDL_thread.h>      // SDL

#ifdef __cplusplus
}
#endif

#pragma comment( lib, "libgcc.a")
#pragma comment( lib, "libmingwex.a")
#pragma comment( lib, "libcoldname.a")
#pragma comment( lib, "libavcodec.a")
#pragma comment( lib, "libavformat.a")
#pragma comment( lib, "libavutil.a")
#pragma comment( lib, "libswscale.a")
#pragma comment( lib, "libz.a")
#pragma comment( lib, "libfaac.a")
#pragma comment( lib, "libgsm.a")
#pragma comment( lib, "libmp3lame.a")
#pragma comment( lib, "libogg.a")
#pragma comment( lib, "libspeex.a")
#pragma comment( lib, "libtheora.a")
#pragma comment( lib, "libvorbis.a")
#pragma comment( lib, "libvorbisenc.a")
#pragma comment( lib, "libx264.a")
#pragma comment( lib, "xvidcore.a")
#pragma comment( lib, "wsock32.lib")
#pragma comment( lib, "vfw32.lib")

#pragma comment( lib, "sdl2main.lib")
#pragma comment( lib, "sdl2.lib")
#pragma   comment(lib, "winmm.lib ")
#pragma	  comment(lib,"Version.lib")
#pragma	  comment(lib,"imm32.lib")

/*  Prevents SDL from overriding main() */
#ifdef __MINGW32__
#undef main
#endif

#define SDL_AUDIO_BUFFER_SIZE 1024
#define MAX_AUDIO_FRAME_SIZE 192000

#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

typedef struct VideoPicture {
AVFrame* rawdata;
int width, height; /* source height & width */
int allocated;
double pts;
SDL_Texture* texture;
} VideoPicture;

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

typedef struct VideoState {

AVFormatContext *pFormatCtx;
int             videoStream, audioStream;

int             av_sync_type;
double          external_clock; /* external clock base */
int64_t         external_clock_time;
int             seek_req;
int             seek_flags;
int64_t         seek_pos;

double          audio_clock;
AVStream        *audio_st;
PacketQueue     audioq;
uint8_t         audio_buf[(MAX_AUDIO_FRAME_SIZE * 3) / 2];
unsigned int    audio_buf_size;
unsigned int    audio_buf_index;
AVFrame         audio_frame;
AVPacket        audio_pkt;
uint8_t         *audio_pkt_data;
int             audio_pkt_size;
int             audio_hw_buf_size;
double          audio_diff_cum; /* used for AV difference average computation */
double          audio_diff_avg_coef;
double          audio_diff_threshold;
int             audio_diff_avg_count;
double          frame_timer;
double          frame_last_pts;
double          frame_last_delay;
double          video_clock; ///<pts of last decoded frame / predicted pts of next decoded frame
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
AVStream        *video_st;
PacketQueue     videoq;

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;

char            filename[1024];
int             quit;

AVIOContext     *io_context;
struct SwsContext *sws_ctx;
struct SDL_Window *pScreen;

} VideoState;

enum {
AV_SYNC_AUDIO_MASTER,
AV_SYNC_VIDEO_MASTER,
AV_SYNC_EXTERNAL_MASTER,
};

/* Since we only have one decoding thread, the Big Struct
can be global in case we need it. */
VideoState *global_video_state;
AVPacket flush_pkt;
//PacketQueue audioq;
//int quit = 0;

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(pkt != &flush_pkt && 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(global_video_state->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;
}
static void packet_queue_flush(PacketQueue *q) {
AVPacketList *pkt, *pkt1;

SDL_LockMutex(q->mutex);
for(pkt = q->first_pkt; pkt != NULL; pkt = pkt1) {
pkt1 = pkt->next;
av_free_packet(&pkt->pkt);
av_freep(&pkt);
}
q->last_pkt = NULL;
q->first_pkt = NULL;
q->nb_packets = 0;
q->size = 0;
SDL_UnlockMutex(q->mutex);
}
double get_audio_clock(VideoState *is) {
double pts;
int hw_buf_size, bytes_per_sec, n;

pts = is->audio_clock; /* maintained in the audio thread */
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;// nb_samples;

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) {
/* remove samples */
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 {
/* difference is TOO big; reset diff stuff */
is->audio_diff_avg_count = 0;
is->audio_diff_cum = 0;
}
}
return samples_size;
}

//int audio_decode_frame(VideoState *is, uint8_t *audio_buf, int buf_size, double *pts_ptr)
//int audio_decode_frame(VideoState *is) {
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) {
/* if error, skip frame */
is->audio_pkt_size = 0;
break;
}
if (got_frame)
{
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;
}
/* We have data, return it and come back for more later */
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);

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) < 0) {
return -1;
}
if(pkt->data == flush_pkt.data) {
avcodec_flush_buffers(is->audio_st->codec);
continue;
}
is->audio_pkt_data = pkt->data;
is->audio_pkt_size = pkt->size;
if(pkt->pts != AV_NOPTS_VALUE) {
is->audio_clock = av_q2d(is->audio_st->time_base)*pkt->pts;
}
}
}

void audio_callback(void *userdata, Uint8 *stream, int len) {

VideoState *is = (VideoState *)userdata;
int len1, audio_size;
double pts;

//这个为SDL2.0增加 ，gongxp 2014注释
SDL_memset(stream, 0, len);
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_Renderer* renderer,SDL_Texture* texture) {

SDL_Rect rect;
VideoPicture *vp;
//AVPicture pict;
float aspect_ratio;
//int w=0, h=0, x=0, y=0;
//screen->w;
//int i;

//renderer->w;

vp = &is->pictq[is->pictq_rindex];
if(vp->rawdata) {
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;
}
//screen->h;
//        h = screen->h;
//        w = ((int)rint(h * aspect_ratio)) & -3;
//        if(w > screen->w) {
//            w = screen->w;
//            h = ((int)rint(w / aspect_ratio)) & -3;
//        }
//        x = (screen->w - w) / 2;
//        y = (screen->h - h) / 2;

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

//SDL_SetRenderDrawColor(renderer, 120, 0, 0, 255);
//SDL_RenderFillRect(renderer, &rect);

//设置窗口大小和视频一样大
SDL_SetWindowSize(is->pScreen,vp->width, vp->height);

SDL_UpdateTexture( texture, &rect, vp->rawdata->data[0], vp->rawdata->linesize[0] );
SDL_RenderClear( renderer );
SDL_RenderCopy( renderer,texture , &rect, &rect );
SDL_RenderPresent( renderer );

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

void video_refresh_timer(void *userdata,SDL_Renderer* renderer) {

VideoState *is = (VideoState *)userdata;
// vp is used in later tutorials for synchronization
VideoPicture *vp = &is->pictq[is->pictq_windex];
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];
/* Now, normally here goes a ton of code
about timing, etc. we're just going to
guess at a delay for now. You can
increase and decrease this value and hard code
the timing - but I don't suggest that ;)
We'll learn how to do it for real later.
schedule_refresh(is, 30);*/
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;

if(is->av_sync_type != AV_SYNC_VIDEO_MASTER) {
/* update delay to sync to audio */
ref_clock = get_audio_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,renderer,vp->texture);

/* 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,SDL_Renderer* renderer) {

VideoState *is = (VideoState *)userdata;
VideoPicture *vp;

vp = &is->pictq[is->pictq_windex];
if(vp->rawdata) {
av_free(vp->rawdata);
}

vp->width = is->video_st->codec->width;
vp->height = is->video_st->codec->height;

//if(vp->texture)SDL_DestroyTexture(vp->texture);
//else vp->texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, vp->width, vp->height);

AVCodecContext *pCodecCtx = NULL;
pCodecCtx = is->video_st->codec;

AVFrame* pFrameYUV = avcodec_alloc_frame();
if( pFrameYUV == NULL )
return;
int numBytes = avpicture_get_size(PIX_FMT_YUV420P, pCodecCtx->width,pCodecCtx->height);
uint8_t* buffer = (uint8_t *)av_malloc(numBytes*sizeof(uint8_t));

avpicture_fill((AVPicture *)pFrameYUV, buffer, PIX_FMT_YUV420P,pCodecCtx->width, pCodecCtx->height);
vp->rawdata = pFrameYUV;

if(vp->texture)SDL_DestroyTexture(vp->texture);
else vp->texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, vp->width, vp->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, double pts){
//int queue_picture(VideoState *is, AVFrame *pFrame) {

VideoPicture *vp;
//AVCodecContext *pCodecCtx;

/* 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->rawdata ||
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(vp->rawdata) {

//SDL_LockYUVOverlay(vp->bmp);

/* 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];

// Convert the image into YUV format that SDL uses
sws_scale(is->sws_ctx,
(uint8_t const * const *)pFrame->data,pFrame->linesize,0,
is->video_st->codec->height,vp->rawdata->data,vp->rawdata->linesize);
//        SDL_Rect rect;
//        rect.x = 0;
//        rect.y = 0;
//        rect.w = vp->width;
//        rect.h = vp->height;
//printf("%d,%d\n",rect.w,rect.h);

//SDL_UpdateTexture( vp->texture, &rect, pFrameYUV->data[0], pFrameYUV->linesize[0] );

//av_free(pFrameYUV);

//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 = (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);
}

int video_thread(void *arg) {
VideoState *is = (VideoState *)arg;
AVPacket pkt1, *packet = &pkt1;
int frameFinished;
AVFrame *pFrame;
double pts;

pFrame = avcodec_alloc_frame();

for(;;) {
if(packet_queue_get(&is->videoq, packet, 1) < 0) {
// means we quit getting packets
break;
}
if(packet->data == flush_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
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);
//printf("video_thread\n");
if(queue_picture(is, pFrame,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 = NULL;
AVCodec *codec = NULL;
AVDictionary *optionsDict = NULL;
SDL_AudioSpec wanted_spec, spec;

if(stream_index < 0 || stream_index >= (int)pFormatCtx->nb_streams) {
return -1;
}

codecCtx = pFormatCtx->streams[stream_index]->codec;

if(codecCtx->codec_type == AVMEDIA_TYPE_AUDIO) {
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;

if(SDL_OpenAudio(&wanted_spec, &spec) < 0) {
fprintf(stderr, "SDL_OpenAudio 失败: %s\n\n", SDL_GetError());
return -1;
}
is->audio_hw_buf_size = spec.size;
}

codec = avcodec_find_decoder(codecCtx->codec_id);
if(!codec || (avcodec_open2(codecCtx, codec, &optionsDict) < 0)) {
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->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, "video_thread",is);
is->sws_ctx = 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_YUV420P,SWS_BILINEAR,NULL,NULL,NULL);

codecCtx->get_buffer = our_get_buffer;
codecCtx->release_buffer = our_release_buffer;

break;
default:
break;
}
return 0;
}

int decode_interrupt_cb(void *opaque) {
return (global_video_state && global_video_state->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;

AVDictionary *io_dict = NULL;
AVIOInterruptCB callback;

is->videoStream=-1;
is->audioStream=-1;

if(SDL_Init( SDL_INIT_AUDIO)) {
fprintf(stderr, "Could not initialize SDL - %s\n", SDL_GetError());
exit(1);
}

//SDL_RenderSetViewport(ctx.renderer, NULL );
//ctx.displayrect.w = ctx.window_w = event.window.data1;
//ctx.displayrect.h = ctx.window_h = event.window.data2;

global_video_state = is;
// will interrupt blocking functions if we quit!
callback.callback = decode_interrupt_cb;
callback.opaque = is;
if (avio_open2(&is->io_context, is->filename, 0, &callback, &io_dict))
{
fprintf(stderr, "Unable to 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

// Dump information about file onto standard error
av_dump_format(pFormatCtx, 0, is->filename, 0);

// Find the first video stream

for(i=0; i<(int)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 stream_index= -1;
int64_t seek_target = is->seek_pos;

if     (is->videoStream >= 0) stream_index = is->videoStream;
else if(is->audioStream >= 0) stream_index = is->audioStream;

if(stream_index>=0){
AVRational r = {1,AV_TIME_BASE };
seek_target= av_rescale_q(seek_target, r, pFormatCtx->streams[stream_index]->time_base);
}
if(!av_seek_frame(is->pFormatCtx, stream_index, seek_target, is->seek_flags)) {
fprintf(stderr, "%s: error while seeking\n", is->pFormatCtx->filename);
} else {
if(is->audioStream >= 0) {
packet_queue_flush(&is->audioq);
packet_queue_put(&is->audioq, &flush_pkt);
}
if(is->videoStream >= 0) {
packet_queue_flush(&is->videoq);
packet_queue_put(&is->videoq, &flush_pkt);
}
}
is->seek_req = 0;
}

if(is->audioq.size > MAX_AUDIOQ_SIZE ||
is->videoq.size > MAX_VIDEOQ_SIZE) {
SDL_Delay(10);
continue;
}
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:
if(1){
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_flags = rel < 0 ? AVSEEK_FLAG_BACKWARD : 0;
is->seek_req = 1;
}
}

int _tmain(int argc, _TCHAR* argv[])
{
SDL_Event       event;
//double          pts;
VideoState      *is;

struct SDL_Window     *pScreen;
struct SDL_Renderer   *pRenderer;

is = (VideoState  *)av_mallocz(sizeof(VideoState));
memset(is,0,sizeof(VideoState));

if(argc < 2) {
fprintf(stderr, "Usage: test <file>\n");
exit(1);
}
// Register all formats and codecs
av_register_all();

//if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)) {
if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER)) {
fprintf(stderr, "Could not initialize SDL - %s\n", SDL_GetError());
exit(1);
}

pScreen = SDL_CreateWindow("audio & video", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 640,480, SDL_WINDOW_OPENGL);
if(!pScreen) {
fprintf(stderr, "SDL: could not set video mode - exiting\n");
exit(1);
}
pRenderer = SDL_CreateRenderer(pScreen, -1, 0);
is->pScreen = pScreen;

SDL_Texture* texture = SDL_CreateTexture(pRenderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, 649, 480);

av_strlcpy(is->filename, argv[1], 1024);

is->pictq_mutex = SDL_CreateMutex();
is->pictq_cond = SDL_CreateCond();

schedule_refresh(is, 40);

is->av_sync_type = DEFAULT_AV_SYNC_TYPE;
is->parse_tid = SDL_CreateThread(decode_thread,"parse_thread", is);
if(!is->parse_tid) {
av_free(is);
return -1;
}

av_init_packet(&flush_pkt);
flush_pkt.data = (uint8_t *)"FLUSH";
for(;;) {
double incr, pos;
SDL_WaitEvent(&event);
switch(event.type) {
case SDL_KEYDOWN:
printf_s("SDL_KEYDOWN\n");
switch(event.key.keysym.sym)
{
case SDLK_LEFT:
incr = -10.0;
goto do_seek;
case SDLK_RIGHT:
incr = 10.0;
goto do_seek;
case SDLK_UP:
incr = 60.0;
goto do_seek;
case SDLK_DOWN:
incr = -60.0;
goto do_seek;
do_seek:
if(global_video_state) {
pos = get_master_clock(global_video_state);
pos += incr;
stream_seek(global_video_state, (int64_t)(pos * AV_TIME_BASE), incr);
}
break;
default:
break;
}
break;
case FF_QUIT_EVENT:
case SDL_QUIT:
is->quit = 1;
/*
* If the video has finished playing, then both the picture and
* audio queues are waiting for more data.  Make them stop
* waiting and terminate normally.
*/
SDL_CondSignal(is->audioq.cond);
SDL_CondSignal(is->videoq.cond);
SDL_Quit();
return 0;
break;
case FF_ALLOC_EVENT:
alloc_picture(event.user.data1,pRenderer);
break;
case FF_REFRESH_EVENT:
video_refresh_timer(event.user.data1,pRenderer);
break;
default:
break;
}
}

SDL_DestroyTexture(texture);

return 0;

}