1、Seek功能

播放本地音视频才有用

对AVFormatContext加锁，因为在seek的时候，不能继续播放，也就是不能继续读取frame了；

pthread_mutex_lock(&seek_mutex);

int64_t rel = secs * AV_TIME_BASE;

avformat_seek_file(pFormatCtx, -1, INT64_MIN, rel, INT64_MAX, 0);

pthread_mutex_unlock(&seek_mutex);

pthread_mutex_lock(&seek_mutex);

ret = av_read_frame(pFormatCtx, packet);

pthread_mutex_unlock(&seek_mutex);

实现Seek方法；

void JfFFmpeg::seek(int64_t sec) {

if (duration < 0){

return;

}

if (sec >= 0 && sec <= duration){

if (audio != NULL){

playStatus->seeking = true;

audio->queue->clearAVPacket();//可能队列中还有一两秒的缓存，所以要清空

audio->clock = 0;//时间置零，需要重新计算

audio->last_time = 0;

pthread_mutex_lock(&seek_mutex);

int64_t rel = sec * AV_TIME_BASE;

avformat_seek_file(pAFmtCtx,-1,INT64_MIN,rel,INT64_MAX,0);

pthread_mutex_unlock(&seek_mutex);

playStatus->seeking = false;

}

}

}

seeking时不再av_read_frame()；

void JfFFmpeg::start() {

if (audio == NULL) {

if (LOG_DEBUG){

LOGE("AUDIO == NULL");

}

}

audio->play();

int count;

while (playStatus != NULL && !playStatus->exit) {

if (playStatus->seeking){

continue;//如果seeking中，不再往下执行

}

if (audio->queue->getQueueSize() > 40){//设置队列只保存40 frames，

continue;

}

AVPacket *avPacket = av_packet_alloc();

pthread_mutex_lock(&seek_mutex);

int ret = av_read_frame(pAFmtCtx,avPacket);

pthread_mutex_unlock(&seek_mutex);

if (ret == 0) {

if (avPacket->stream_index == audio->streamIndex){

count++;

/*if (LOG_DEBUG) {

LOGD("解码第%d帧",count);

}*/

audio->queue->putAVPacket(avPacket);

} else {

av_packet_free(&avPacket);

av_free(avPacket);

avPacket = NULL;

}

} else {

av_packet_free(&avPacket);

av_free(avPacket);

avPacket = NULL;

//队列中的avPacket还没有解码完

while (playStatus != NULL && !playStatus->exit){

if (audio->queue->getQueueSize() > 0){//把缓存中的avPacket也要释放出来

continue;

} else {

playStatus->exit = true;

break;

}

}

}

}

exit = true;

}

}

Java层调用

extern "C"

JNIEXPORT void JNICALL

Java_com_example_myplayer_player_JfPlayer_n_1seek(JNIEnv *env, jobject instance, jint sec) {

// TODO

if (ffmpeg != NULL){

ffmpeg->seek(sec);

}

}

2、完成播放回调

在最后调用完成接口即可。

创建完成播放接口，供C++层调用：

public interface JfOnCompleteListener {

void onComplete();

}

private JfOnCompleteListener jfOnCompleteListener;

public void setJfOnCompleteListener(JfOnCompleteListener jfOnCompleteListener) {

this.jfOnCompleteListener = jfOnCompleteListener;

}

public void onCallComplete(){

stop();

if (jfOnCompleteListener != null) {

jfOnCompleteListener.onComplete();

}

}

然后就是C++调用Java方法的流程，在

void JfFFmpeg::start() {

if (audio == NULL) {

if (LOG_DEBUG){

LOGE("AUDIO == NULL");

}

}

audio->play();

int count;

while (playStatus != NULL && !playStatus->exit) {

if (playStatus->seeking){

continue;//如果seeking中，不再往下执行

}

if (audio->queue->getQueueSize() > 40){//设置队列只保存40 frames，

continue;

}

AVPacket *avPacket = av_packet_alloc();

pthread_mutex_lock(&seek_mutex);

int ret = av_read_frame(pAFmtCtx,avPacket);

pthread_mutex_unlock(&seek_mutex);

if (ret == 0) {

if (avPacket->stream_index == audio->streamIndex){

count++;

/*if (LOG_DEBUG) {

LOGD("解码第%d帧",count);

}*/

audio->queue->putAVPacket(avPacket);

} else {

av_packet_free(&avPacket);

av_free(avPacket);

avPacket = NULL;

}

} else {

av_packet_free(&avPacket);

av_free(avPacket);

avPacket = NULL;

//队列中的avPacket还没有解码完

while (playStatus != NULL && !playStatus->exit){

if (audio->queue->getQueueSize() > 0){//把缓存中的avPacket也要释放出来

continue;

} else {

playStatus->exit = true;

break;

}

}

}

}

if (callJava != NULL){

callJava->onCallComplete(CHILD_THREAD);

}

exit = true;

}

}

并为start方法创建一个子线程：

void *startCallback(void *data){

JfFFmpeg *ffmpeg = (JfFFmpeg *)data;

ffmpeg->start();

pthread_exit(&thread_start);

}

extern "C"

JNIEXPORT void JNICALL

Java_com_example_myplayer_player_JfPlayer_n_1start(JNIEnv *env, jobject instance) {

// TODO

if (ffmpeg != NULL){

//ffmpeg->start();

pthread_create(&thread_start,NULL,startCallback,ffmpeg);

}

}