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pull/166/head
xufulong 5 years ago
parent 781ec7444e
commit 3e4def578d
2 changed files with 65 additions and 81 deletions
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  1. 128
      app/src/main/cpp/media_player.c

128
app/src/main/cpp/media_player.c
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@ -72,23 +72,23 @@ jint JNICALL JNI_OnLoad(JavaVM* vm, void* reserved){
return JNI_VERSION_1_6; return JNI_VERSION_1_6;
} }
//初始化输入格式上下文 //init player
int init_input_format_context(MediaPlayer* player, const char* file_name){ int init_input_format_context(MediaPlayer* player, const char* file_name){
//注册所有组件 //register all modules
av_register_all(); av_register_all();
//分配上下文 //alloc format context
player->format_context = avformat_alloc_context(); player->format_context = avformat_alloc_context();
//打开视频文件 //open the input file
if(avformat_open_input(&player->format_context, file_name, NULL, NULL)!=0) { if(avformat_open_input(&player->format_context, file_name, NULL, NULL)!=0) {
LOGE(TAG, "Couldn't open file:%s\n", file_name); LOGE(TAG, "Couldn't open file:%s\n", file_name);
return -1; return -1;
} }
//检索多媒体流信息 //find the info of all streams
if(avformat_find_stream_info(player->format_context, NULL)<0) { if(avformat_find_stream_info(player->format_context, NULL)<0) {
LOGE(TAG, "Couldn't find stream information."); LOGE(TAG, "Couldn't find stream information.");
return -1; return -1;
} }
//寻找音视频流索引位置 //find the index of audio and video stream
int i; int i;
player->video_stream_index = -1; player->video_stream_index = -1;
player->audio_stream_index = -1; player->audio_stream_index = -1;
@ -114,11 +114,11 @@ int init_input_format_context(MediaPlayer* player, const char* file_name){
return 0; return 0;
} }
//打开音视频解码器 //open decoder
int init_condec_context(MediaPlayer* player){ int init_condec_context(MediaPlayer* player){
//获取codec上下文指针 //get codec context
player->video_codec_context = player->format_context->streams[player->video_stream_index]->codec; player->video_codec_context = player->format_context->streams[player->video_stream_index]->codec;
//寻找视频流的解码器 //find audio and video decoder
player->video_codec = avcodec_find_decoder(player->video_codec_context->codec_id); player->video_codec = avcodec_find_decoder(player->video_codec_context->codec_id);
if(player->video_codec == NULL) { if(player->video_codec == NULL) {
LOGE(TAG, "couldn't find video Codec."); LOGE(TAG, "couldn't find video Codec.");
@ -138,25 +138,24 @@ int init_condec_context(MediaPlayer* player){
LOGE(TAG, "Couldn't open audio codec."); LOGE(TAG, "Couldn't open audio codec.");
return -1; return -1;
} }
// 获取视频宽高 // width and height
player->video_width = player->video_codec_context->width; player->video_width = player->video_codec_context->width;
player->video_height = player->video_codec_context->height; player->video_height = player->video_codec_context->height;
return 0; return 0;
} }
//视频解码
void video_player_prepare(MediaPlayer* player, JNIEnv* env, jobject surface){ void video_player_prepare(MediaPlayer* player, JNIEnv* env, jobject surface){
// 获取native window // get native window
player->native_window = ANativeWindow_fromSurface(env, surface); player->native_window = ANativeWindow_fromSurface(env, surface);
} }
//获取当前播放时间 //get current playing time
int64_t get_play_time(MediaPlayer* player){ int64_t get_play_time(MediaPlayer* player){
return (int64_t)(av_gettime() - player->start_time); return (int64_t)(av_gettime() - player->start_time);
} }
/** /**
* 延迟等待，音视频同步 * audio and video synchronization
*/ */
void player_wait_for_frame(MediaPlayer *player, int64_t stream_time) { void player_wait_for_frame(MediaPlayer *player, int64_t stream_time) {
pthread_mutex_lock(&player->mutex); pthread_mutex_lock(&player->mutex);
@ -180,7 +179,7 @@ void player_wait_for_frame(MediaPlayer *player, int64_t stream_time) {
// and check everything again // and check everything again
sleep_time = 500000ll; sleep_time = 500000ll;
} }
//TODO:等待指定时长 //TODO: waiting util time out
// pthread_cond_timeout_np(&player->cond, &player->mutex, // pthread_cond_timeout_np(&player->cond, &player->mutex,
// (unsigned int) (sleep_time / 1000ll)); // (unsigned int) (sleep_time / 1000ll));
gettimeofday(&now, NULL); gettimeofday(&now, NULL);
@ -191,14 +190,12 @@ void player_wait_for_frame(MediaPlayer *player, int64_t stream_time) {
pthread_mutex_unlock(&player->mutex); pthread_mutex_unlock(&player->mutex);
} }
//视频解码 //decode video packet as a frame
int decode_video(MediaPlayer* player, AVPacket* packet){ int decode_video(MediaPlayer* player, AVPacket* packet){
// 设置native window的buffer大小,可自动拉伸
ANativeWindow_setBuffersGeometry(player->native_window, player->video_width, ANativeWindow_setBuffersGeometry(player->native_window, player->video_width,
player->video_height, WINDOW_FORMAT_RGBA_8888); player->video_height, WINDOW_FORMAT_RGBA_8888);
ANativeWindow_Buffer windowBuffer; ANativeWindow_Buffer windowBuffer;
//申请内存
player->yuv_frame = av_frame_alloc(); player->yuv_frame = av_frame_alloc();
player->rgba_frame = av_frame_alloc(); player->rgba_frame = av_frame_alloc();
if(player->rgba_frame == NULL || player->yuv_frame == NULL) { if(player->rgba_frame == NULL || player->yuv_frame == NULL) {
@ -206,14 +203,13 @@ int decode_video(MediaPlayer* player, AVPacket* packet){
return -1; return -1;
} }
// buffer中数据用于渲染,且格式为RGBA // get buffer size, the format is RGBA
int numBytes=av_image_get_buffer_size(AV_PIX_FMT_RGBA, player->video_width, player->video_height, 1); int numBytes=av_image_get_buffer_size(AV_PIX_FMT_RGBA, player->video_width, player->video_height, 1);
player->buffer = (uint8_t *)av_malloc(numBytes*sizeof(uint8_t)); player->buffer = (uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
av_image_fill_arrays(player->rgba_frame->data, player->rgba_frame->linesize, player->buffer, AV_PIX_FMT_RGBA, av_image_fill_arrays(player->rgba_frame->data, player->rgba_frame->linesize, player->buffer, AV_PIX_FMT_RGBA,
player->video_width, player->video_height, 1); player->video_width, player->video_height, 1);
// 由于解码出来的帧格式不是RGBA的,在渲染之前需要进行格式转换
struct SwsContext *sws_ctx = sws_getContext( struct SwsContext *sws_ctx = sws_getContext(
player->video_width, player->video_width,
player->video_height, player->video_height,
@ -227,7 +223,7 @@ int decode_video(MediaPlayer* player, AVPacket* packet){
NULL); NULL);
int frameFinished; int frameFinished;
//对该帧进行解码 //decode video frame
int ret = avcodec_decode_video2(player->video_codec_context, player->yuv_frame, &frameFinished, packet); int ret = avcodec_decode_video2(player->video_codec_context, player->yuv_frame, &frameFinished, packet);
if(ret < 0){ if(ret < 0){
LOGE(TAG, "avcodec_decode_video2 error..."); LOGE(TAG, "avcodec_decode_video2 error...");
@ -236,27 +232,26 @@ int decode_video(MediaPlayer* player, AVPacket* packet){
if (frameFinished) { if (frameFinished) {
// lock native window // lock native window
ANativeWindow_lock(player->native_window, &windowBuffer, 0); ANativeWindow_lock(player->native_window, &windowBuffer, 0);
// 格式转换 // yuv to rgba
sws_scale(sws_ctx, (uint8_t const * const *)player->yuv_frame->data, sws_scale(sws_ctx, (uint8_t const * const *)player->yuv_frame->data,
player->yuv_frame->linesize, 0, player->video_height, player->yuv_frame->linesize, 0, player->video_height,
player->rgba_frame->data, player->rgba_frame->linesize); player->rgba_frame->data, player->rgba_frame->linesize);
// 获取stride
uint8_t * dst = windowBuffer.bits; uint8_t * dst = windowBuffer.bits;
int dstStride = windowBuffer.stride * 4; int dstStride = windowBuffer.stride * 4;
uint8_t * src = player->rgba_frame->data[0]; uint8_t * src = player->rgba_frame->data[0];
int srcStride = player->rgba_frame->linesize[0]; int srcStride = player->rgba_frame->linesize[0];
// 由于window的stride和帧的stride不同,因此需要逐行复制 // copy data to the target buffer
int h; int h;
for (h = 0; h < player->video_height; h++) { for (h = 0; h < player->video_height; h++) {
memcpy(dst + h * dstStride, src + h * srcStride, (size_t) srcStride); memcpy(dst + h * dstStride, src + h * srcStride, (size_t) srcStride);
} }
//计算延迟 //calculate pts
int64_t pts = av_frame_get_best_effort_timestamp(player->yuv_frame); int64_t pts = av_frame_get_best_effort_timestamp(player->yuv_frame);
AVStream *stream = player->format_context->streams[player->video_stream_index]; AVStream *stream = player->format_context->streams[player->video_stream_index];
//转换（不同时间基时间转换） //convert to real time
int64_t time = av_rescale_q(pts, stream->time_base, AV_TIME_BASE_Q); int64_t time = av_rescale_q(pts, stream->time_base, AV_TIME_BASE_Q);
//音视频帧同步 //synchronize
player_wait_for_frame(player, time); player_wait_for_frame(player, time);
ANativeWindow_unlockAndPost(player->native_window); ANativeWindow_unlockAndPost(player->native_window);
@ -264,21 +259,21 @@ int decode_video(MediaPlayer* player, AVPacket* packet){
return 0; return 0;
} }
//音频解码初始化 //init audio decoder
void audio_decoder_prepare(MediaPlayer* player) { void audio_decoder_prepare(MediaPlayer* player) {
player->swrContext = swr_alloc(); player->swrContext = swr_alloc();
//输入的采样格式 //input format
enum AVSampleFormat in_sample_fmt = player->audio_codec_context->sample_fmt; enum AVSampleFormat in_sample_fmt = player->audio_codec_context->sample_fmt;
//输出采样格式16bit PCM //output format
player->out_sample_fmt = AV_SAMPLE_FMT_S16; player->out_sample_fmt = AV_SAMPLE_FMT_S16;
//输入采样率 //input sampleRate
int in_sample_rate = player->audio_codec_context->sample_rate; int in_sample_rate = player->audio_codec_context->sample_rate;
//输出采样率 //output sampleRate
player->out_sample_rate = in_sample_rate; player->out_sample_rate = in_sample_rate;
//声道布局（2个声道，默认立体声stereo） //channel layout (stereo by default)
uint64_t in_ch_layout = player->audio_codec_context->channel_layout; uint64_t in_ch_layout = player->audio_codec_context->channel_layout;
//输出的声道布局（立体声） //output channel layout
uint64_t out_ch_layout = AV_CH_LAYOUT_STEREO; uint64_t out_ch_layout = AV_CH_LAYOUT_STEREO;
swr_alloc_set_opts(player->swrContext, swr_alloc_set_opts(player->swrContext,
@ -286,17 +281,15 @@ void audio_decoder_prepare(MediaPlayer* player) {
in_ch_layout, in_sample_fmt, in_sample_rate, in_ch_layout, in_sample_fmt, in_sample_rate,
0, NULL); 0, NULL);
swr_init(player->swrContext); swr_init(player->swrContext);
//输出的声道个数
player->out_channel_nb = av_get_channel_layout_nb_channels(out_ch_layout); player->out_channel_nb = av_get_channel_layout_nb_channels(out_ch_layout);
} }
//音频播放器
void audio_player_prepare(MediaPlayer* player, JNIEnv* env, jclass jthiz){ void audio_player_prepare(MediaPlayer* player, JNIEnv* env, jclass jthiz){
jclass player_class = (*env)->GetObjectClass(env,jthiz); jclass player_class = (*env)->GetObjectClass(env,jthiz);
if(!player_class){ if(!player_class){
LOGE(TAG, "player_class not found..."); LOGE(TAG, "player_class not found...");
} }
//AudioTrack对象 //get AudioTrack by reflection
jmethodID audio_track_method = (*env)->GetMethodID( jmethodID audio_track_method = (*env)->GetMethodID(
env,player_class,"createAudioTrack","(II)Landroid/media/AudioTrack;"); env,player_class,"createAudioTrack","(II)Landroid/media/AudioTrack;");
if(!audio_track_method){ if(!audio_track_method){
@ -305,38 +298,41 @@ void audio_player_prepare(MediaPlayer* player, JNIEnv* env, jclass jthiz){
jobject audio_track = (*env)->CallObjectMethod( jobject audio_track = (*env)->CallObjectMethod(
env,jthiz,audio_track_method, player->out_sample_rate, player->out_channel_nb); env,jthiz,audio_track_method, player->out_sample_rate, player->out_channel_nb);
//调用play方法
jclass audio_track_class = (*env)->GetObjectClass(env, audio_track); jclass audio_track_class = (*env)->GetObjectClass(env, audio_track);
jmethodID audio_track_play_mid = (*env)->GetMethodID(env,audio_track_class,"play","()V"); jmethodID audio_track_play_mid = (*env)->GetMethodID(env,audio_track_class,"play","()V");
(*env)->CallVoidMethod(env, audio_track, audio_track_play_mid); (*env)->CallVoidMethod(env, audio_track, audio_track_play_mid);
player->audio_track = (*env)->NewGlobalRef(env, audio_track); player->audio_track = (*env)->NewGlobalRef(env, audio_track);
//获取write()方法
player->audio_track_write_mid = (*env)->GetMethodID(env,audio_track_class,"write","([BII)I"); player->audio_track_write_mid = (*env)->GetMethodID(env,audio_track_class,"write","([BII)I");
//16bit 44100 PCM 数据 //malloc buffer
player->audio_buffer = (uint8_t *)av_malloc(MAX_AUDIO_FRAME_SIZE); player->audio_buffer = (uint8_t *)av_malloc(MAX_AUDIO_FRAME_SIZE);
//解压缩数据
player->audio_frame = av_frame_alloc(); player->audio_frame = av_frame_alloc();
} }
//音频解码 //audio decode function
int decode_audio(MediaPlayer* player, AVPacket* packet){ int decode_audio(MediaPlayer* player, AVPacket* packet){
int got_frame = 0, ret; int got_frame = 0, ret;
//解码
ret = avcodec_decode_audio4(player->audio_codec_context, player->audio_frame, &got_frame, packet); ret = avcodec_decode_audio4(player->audio_codec_context, player->audio_frame, &got_frame, packet);
if(ret < 0){ if(ret < 0){
LOGE(TAG, "avcodec_decode_audio4 error..."); LOGE(TAG, "avcodec_decode_audio4 error...");
return -1; return -1;
} }
//解码一帧成功 //decode success
if(got_frame > 0){ if(got_frame > 0){
//音频格式转换 //convert audio format
swr_convert(player->swrContext, &player->audio_buffer, MAX_AUDIO_FRAME_SIZE, (const uint8_t **)player->audio_frame->data, player->audio_frame->nb_samples); swr_convert(player->swrContext,
int out_buffer_size = av_samples_get_buffer_size(NULL, player->out_channel_nb, &player->audio_buffer,
player->audio_frame->nb_samples, player->out_sample_fmt, 1); MAX_AUDIO_FRAME_SIZE,
(const uint8_t **)player->audio_frame->data,
//音视频帧同步 player->audio_frame->nb_samples);
int out_buffer_size = av_samples_get_buffer_size(NULL,
player->out_channel_nb,
player->audio_frame->nb_samples,
player->out_sample_fmt,
1);
//synchronize
int64_t pts = packet->pts; int64_t pts = packet->pts;
if (pts != AV_NOPTS_VALUE) { if (pts != AV_NOPTS_VALUE) {
AVStream *stream = player->format_context->streams[player->audio_stream_index]; AVStream *stream = player->format_context->streams[player->audio_stream_index];
@ -349,14 +345,12 @@ int decode_audio(MediaPlayer* player, AVPacket* packet){
(*javaVM)->AttachCurrentThread(javaVM, &env, NULL); (*javaVM)->AttachCurrentThread(javaVM, &env, NULL);
jbyteArray audio_sample_array = (*env)->NewByteArray(env,out_buffer_size); jbyteArray audio_sample_array = (*env)->NewByteArray(env,out_buffer_size);
jbyte* sample_byte_array = (*env)->GetByteArrayElements(env,audio_sample_array,NULL); jbyte* sample_byte_array = (*env)->GetByteArrayElements(env,audio_sample_array,NULL);
//拷贝缓冲数据
memcpy(sample_byte_array, player->audio_buffer, (size_t) out_buffer_size); memcpy(sample_byte_array, player->audio_buffer, (size_t) out_buffer_size);
//释放数组
(*env)->ReleaseByteArrayElements(env,audio_sample_array,sample_byte_array,0); (*env)->ReleaseByteArrayElements(env,audio_sample_array,sample_byte_array,0);
//调用AudioTrack的write方法进行播放 //call write method of AudioTrack to play
(*env)->CallIntMethod(env, player->audio_track, player->audio_track_write_mid, (*env)->CallIntMethod(env, player->audio_track, player->audio_track_write_mid,
audio_sample_array,0,out_buffer_size); audio_sample_array,0,out_buffer_size);
//释放局部引用 //release local reference
(*env)->DeleteLocalRef(env,audio_sample_array); (*env)->DeleteLocalRef(env,audio_sample_array);
} }
} }
@ -366,7 +360,6 @@ int decode_audio(MediaPlayer* player, AVPacket* packet){
return 0; return 0;
} }
//初始化队列
void init_queue(MediaPlayer* player, int size){ void init_queue(MediaPlayer* player, int size){
int i; int i;
for (i = 0; i < 2; ++i) { for (i = 0; i < 2; ++i) {
@ -375,7 +368,6 @@ void init_queue(MediaPlayer* player, int size){
} }
} }
//释放队列
void delete_queue(MediaPlayer* player){ void delete_queue(MediaPlayer* player){
int i; int i;
for (i = 0; i < 2; ++i) { for (i = 0; i < 2; ++i) {
@ -383,7 +375,7 @@ void delete_queue(MediaPlayer* player){
} }
} }
//读取AVPacket线程(生产者) //the thread of write packet
void* write_packet_to_queue(void* arg){ void* write_packet_to_queue(void* arg){
MediaPlayer* player = (MediaPlayer*)arg; MediaPlayer* player = (MediaPlayer*)arg;
AVPacket packet, *pkt = &packet; AVPacket packet, *pkt = &packet;
@ -394,23 +386,20 @@ void* write_packet_to_queue(void* arg){
break; break;
} }
if(pkt->stream_index == player->video_stream_index || pkt->stream_index == player->audio_stream_index){ if(pkt->stream_index == player->video_stream_index || pkt->stream_index == player->audio_stream_index){
//根据AVPacket->stream_index获取对应的队列
AVPacketQueue *queue = player->packets[pkt->stream_index]; AVPacketQueue *queue = player->packets[pkt->stream_index];
pthread_mutex_lock(&player->mutex); pthread_mutex_lock(&player->mutex);
AVPacket* data = queue_push(queue, &player->mutex, &player->cond); AVPacket* data = queue_push(queue, &player->mutex, &player->cond);
pthread_mutex_unlock(&player->mutex); pthread_mutex_unlock(&player->mutex);
//拷贝（间接赋值，拷贝结构体数据）
*data = packet; *data = packet;
} }
} }
} }
//音视频解码线程(消费者) //the thread of decoding
void* decode_func(void* arg){ void* decode_func(void* arg){
Decoder *decoder_data = (Decoder*)arg; Decoder *decoder_data = (Decoder*)arg;
MediaPlayer *player = decoder_data->player; MediaPlayer *player = decoder_data->player;
int stream_index = decoder_data->stream_index; int stream_index = decoder_data->stream_index;
//根据stream_index获取对应的AVPacket队列
AVPacketQueue *queue = player->packets[stream_index]; AVPacketQueue *queue = player->packets[stream_index];
int ret = 0; int ret = 0;
@ -419,9 +408,9 @@ void* decode_func(void* arg){
AVPacket *packet = (AVPacket*)queue_pop(queue, &player->mutex, &player->cond); AVPacket *packet = (AVPacket*)queue_pop(queue, &player->mutex, &player->cond);
pthread_mutex_unlock(&player->mutex); pthread_mutex_unlock(&player->mutex);
if(stream_index == player->video_stream_index) {//视频流 if(stream_index == player->video_stream_index) {//video stream
ret = decode_video(player, packet); ret = decode_video(player, packet);
} else if(stream_index == player->audio_stream_index) {//音频流 } else if(stream_index == player->audio_stream_index) {//audio stream
ret = decode_audio(player, packet); ret = decode_audio(player, packet);
} }
av_packet_unref(packet); av_packet_unref(packet);
@ -439,23 +428,21 @@ MEDIA_PLAYER_FUNC(jint, setup, jstring filePath, jobject surface){
if(player == NULL){ if(player == NULL){
return -1; return -1;
} }
//初始化输入格式上下文
ret = init_input_format_context(player, file_name); ret = init_input_format_context(player, file_name);
if(ret < 0){ if(ret < 0){
return ret; return ret;
} }
//初始化音视频解码器
ret = init_condec_context(player); ret = init_condec_context(player);
if(ret < 0){ if(ret < 0){
return ret; return ret;
} }
//初始化视频surface //init surface
video_player_prepare( player, env, surface); video_player_prepare( player, env, surface);
//初始化音频相关参数 //init params of player
audio_decoder_prepare(player); audio_decoder_prepare(player);
//初始化音频播放器 //init player
audio_player_prepare(player, env, thiz); audio_player_prepare(player, env, thiz);
//初始化音视频packet队列 //init queue
init_queue(player, PACKET_SIZE); init_queue(player, PACKET_SIZE);
return 0; return 0;
@ -465,12 +452,10 @@ MEDIA_PLAYER_FUNC(jint, play){
pthread_mutex_init(&player->mutex, NULL); pthread_mutex_init(&player->mutex, NULL);
pthread_cond_init(&player->cond, NULL); pthread_cond_init(&player->cond, NULL);
//生产者线程
pthread_create(&player->write_thread, NULL, write_packet_to_queue, (void*)player); pthread_create(&player->write_thread, NULL, write_packet_to_queue, (void*)player);
sleep(1); sleep(1);
player->start_time = 0; player->start_time = 0;
//消费者线程
Decoder data1 = {player, player->video_stream_index}, *decoder_data1 = &data1; Decoder data1 = {player, player->video_stream_index}, *decoder_data1 = &data1;
pthread_create(&player->video_thread, NULL, decode_func, (void*)decoder_data1); pthread_create(&player->video_thread, NULL, decode_func, (void*)decoder_data1);
@ -486,7 +471,6 @@ MEDIA_PLAYER_FUNC(jint, play){
} }
MEDIA_PLAYER_FUNC(void, release){ MEDIA_PLAYER_FUNC(void, release){
//释放内存以及关闭文件
free(player->audio_track); free(player->audio_track);
free(player->audio_track_write_mid); free(player->audio_track_write_mid);
av_free(player->buffer); av_free(player->buffer);

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