Android 采集摄像头数据 , 通过ffmpeg推送流, 通过AdobeMediaServer查看 , 为什么播放视频总是隔一段时间一缓冲 , 而且播放有延迟。求大神帮忙啊
AVFormatContext *ofmt_ctx;
AVStream* video_st;
//视音频流对应的结构体,用于视音频编解码。
AVCodecContext* pCodecCtx;
AVCodec* pCodec;
AVPacket enc_pkt; // 存储压缩数据(视频对应H.264等码流数据,音频对应AAC/MP3等码流数据)
AVFrame *pFrameYUV; // 存储非压缩的数据(视频对应RGB/YUV像素数据,音频对应PCM采样数据)
int framecnt = 0;
int yuv_width;
int yuv_height;
int y_length;
int uv_length;
int64_t start_time;
//const char* out_path = "rtmp://192.168.2.176/live/livestream";
//Output FFmpeg's av_log()
void custom_log(void *ptr, int level, const char* fmt, va_list vl) {
FILE *fp = fopen("/storage/emulated/0/av_log.txt", "a+");
if (fp) {
vfprintf(fp, fmt, vl);
fflush(fp);
fclose(fp);
}
}
JNIEXPORT jint JNICALL Java_com_zhanghui_test_MainActivity_initial(JNIEnv *env,
jobject obj, jint width, jint height) {
const char* out_path = "rtmp://192.168.2.176/live/livestream";
yuv_width = width;
yuv_height = height;
y_length = width * height;
uv_length = width * height / 4;
//FFmpeg av_log() callback
av_log_set_callback(custom_log);
av_register_all();
avformat_network_init();
//output initialize
avformat_alloc_output_context2(&ofmt_ctx, NULL, "flv", out_path);
//output encoder initialize
//函数的参数是一个解码器的ID,返回查找到的解码器(没有找到就返回NULL)。
pCodec = avcodec_find_encoder(AV_CODEC_ID_H264);
if (!pCodec) {
LOGE("Can not find encoder!\n");
return -1;
}
pCodecCtx = avcodec_alloc_context3(pCodec);
pCodecCtx->pix_fmt = PIX_FMT_YUV420P;
pCodecCtx->width = width;
pCodecCtx->height = height;
pCodecCtx->time_base.num = 1;
pCodecCtx->time_base.den = 25;
pCodecCtx->bit_rate = 400000;
pCodecCtx->gop_size = 250;
/* Some formats want stream headers to be separate. */
if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
pCodecCtx->flags |= CODEC_FLAG_GLOBAL_HEADER;
//H264 codec param
//pCodecCtx->me_range = 16;
//pCodecCtx->max_qdiff = 4;
//pCodecCtx->qcompress = 0.6;
pCodecCtx->qmin = 10;
pCodecCtx->qmax = 51;
//Optional Param
pCodecCtx->max_b_frames = 1;
// Set H264 preset and tune
AVDictionary *param = 0;
// av_dict_set(¶m, "preset", "ultrafast", 0);
// av_dict_set(¶m, "tune", "zerolatency", 0);
av_opt_set(pCodecCtx->priv_data, "preset", "superfast", 0);
av_opt_set(pCodecCtx->priv_data, "tune", "zerolatency", 0);
//打开编码器
if (avcodec_open2(pCodecCtx, pCodec, ¶m) < 0) {
LOGE("Failed to open encoder!\n");
return -1;
}
//Add a new stream to output,should be called by the user before avformat_write_header() for muxing
video_st = avformat_new_stream(ofmt_ctx, pCodec);
if (video_st == NULL) {
return -1;
}
video_st->time_base.num = 1;
video_st->time_base.den = 25;
video_st->codec = pCodecCtx;
//Open output URL,set before avformat_write_header() for muxing
if (avio_open(&ofmt_ctx->pb, out_path, AVIO_FLAG_READ_WRITE) < 0) {
LOGE("Failed to open output file!\n");
return -1;
}
//Write File Header
avformat_write_header(ofmt_ctx, NULL);
start_time = av_gettime();
return 0;
}
JNIEXPORT jint JNICALL Java_com_zhanghui_test_MainActivity_encode(JNIEnv *env,
jobject obj, jbyteArray yuv) {
int ret;
int enc_got_frame = 0;
int i = 0;
// 为解码帧分配内存
pFrameYUV = avcodec_alloc_frame();
uint8_t *out_buffer = (uint8_t *) av_malloc(
avpicture_get_size(PIX_FMT_YUV420P, pCodecCtx->width,
pCodecCtx->height));
avpicture_fill((AVPicture *) pFrameYUV, out_buffer, PIX_FMT_YUV420P,
pCodecCtx->width, pCodecCtx->height);
//安卓摄像头数据为NV21格式,此处将其转换为YUV420P格式
jbyte* in = (jbyte*) (*env)->GetByteArrayElements(env, yuv, 0);
memcpy(pFrameYUV->data[0], in, y_length);
for (i = 0; i < uv_length; i++) {
*(pFrameYUV->data[2] + i) = *(in + y_length + i * 2);
*(pFrameYUV->data[1] + i) = *(in + y_length + i * 2 + 1);
}
pFrameYUV->format = AV_PIX_FMT_YUV420P;
pFrameYUV->width = yuv_width;
pFrameYUV->height = yuv_height;
enc_pkt.data = NULL;
enc_pkt.size = 0;
// 定义AVPacket对象后,请使用av_init_packet进行初始化
av_init_packet(&enc_pkt);
/** 编码一帧视频数据
* int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
const AVFrame *frame, int *got_packet_ptr);
该函数每个参数的含义在注释里面已经写的很清楚了,在这里用中文简述一下:
avctx:编码器的AVCodecContext。
avpkt:编码输出的AVPacket。
frame:编码输入的AVFrame。
got_packet_ptr:成功编码一个AVPacket的时候设置为1。
函数返回0代表编码成功。
*/
ret = avcodec_encode_video2(pCodecCtx, &enc_pkt, pFrameYUV, &enc_got_frame);
av_frame_free(&pFrameYUV);
if (enc_got_frame == 1) {
LOGI("Succeed to encode frame: %5d\tsize:%5d\n", framecnt,
enc_pkt.size);
framecnt++;
//标识该AVPacket所属的视频/音频流。
enc_pkt.stream_index = video_st->index; //标识该视频/音频流
//Write PTS
AVRational time_base = ofmt_ctx->streams[0]->time_base; //{ 1, 1000 };
AVRational r_framerate1 = { 60, 2 }; //{ 50, 2 };
AVRational time_base_q = { 1, AV_TIME_BASE };
//Duration between 2 frames (us)
int64_t calc_duration = (double) (AV_TIME_BASE)
* (1 / av_q2d(r_framerate1)); //内部时间戳
//Parameters
//enc_pkt.pts = (double)(framecnt*calc_duration)*(double)(av_q2d(time_base_q)) / (double)(av_q2d(time_base));
enc_pkt.pts = av_rescale_q(framecnt * calc_duration, time_base_q,
time_base);
enc_pkt.dts = enc_pkt.pts;
enc_pkt.duration = av_rescale_q(calc_duration, time_base_q, time_base); //(double)(calc_duration)*(double)(av_q2d(time_base_q)) / (double)(av_q2d(time_base));
enc_pkt.pos = -1;
//Delay
int64_t pts_time = av_rescale_q(enc_pkt.dts, time_base, time_base_q);
int64_t now_time = av_gettime() - start_time;
if (pts_time > now_time)
av_usleep(pts_time - now_time);
ret = av_interleaved_write_frame(ofmt_ctx, &enc_pkt);
av_free_packet(&enc_pkt);
}
// output(ofmt_ctx);
return 0;
}
JNIEXPORT jint JNICALL Java_com_zhanghui_test_MainActivity_flush(JNIEnv *env,
jobject obj) {
int ret;
int got_frame;
AVPacket enc_pkt;
if (!(ofmt_ctx->streams[0]->codec->codec->capabilities & CODEC_CAP_DELAY))
return 0;
while (1) {
enc_pkt.data = NULL;
enc_pkt.size = 0;
av_init_packet(&enc_pkt);
ret = avcodec_encode_video2(ofmt_ctx->streams[0]->codec, &enc_pkt, NULL,
&got_frame);
if (ret < 0)
break;
if (!got_frame) {
ret = 0;
break;
}
LOGI("Flush Encoder: Succeed to encode 1 frame!\tsize:%5d\n",
enc_pkt.size);
//Write PTS
AVRational time_base = ofmt_ctx->streams[0]->time_base; //{ 1, 1000 };
AVRational r_framerate1 = { 60, 2 };
AVRational time_base_q = { 1, AV_TIME_BASE };
//Duration between 2 frames (us)
int64_t calc_duration = (double) (AV_TIME_BASE)
* (1 / av_q2d(r_framerate1)); //内部时间戳
//Parameters
enc_pkt.pts = av_rescale_q(framecnt * calc_duration, time_base_q,
time_base);
enc_pkt.dts = enc_pkt.pts;
enc_pkt.duration = av_rescale_q(calc_duration, time_base_q, time_base);
//转换PTS/DTS(Convert PTS/DTS)
enc_pkt.pos = -1;
framecnt++;
ofmt_ctx->duration = enc_pkt.duration * framecnt;
/* mux encoded frame */
ret = av_interleaved_write_frame(ofmt_ctx, &enc_pkt);
if (ret < 0)
break;
}
//Write file trailer
av_write_trailer(ofmt_ctx);
return 0;
}
JNIEXPORT jint JNICALL Java_com_zhanghui_test_MainActivity_close(JNIEnv *env,
jobject obj) {
if (video_st)
avcodec_close(video_st->codec);
avio_close(ofmt_ctx->pb);
avformat_free_context(ofmt_ctx);
return 0;
}