public void StartPlay(NetworkStream stream)
{
try
{
AVCodec *mCodec = ffmpeg.avcodec_find_decoder(AVCodecID.AV_CODEC_ID_H264);
if (mCodec == null)
{
Console.WriteLine("can not find h264 decoder");
return;
}
AVCodecContext *mCodecContext = ffmpeg.avcodec_alloc_context3(mCodec);
if (mCodecContext == null)
{
Console.WriteLine("can not allcote codec context");
return;
}
if (ffmpeg.avcodec_open2(mCodecContext, mCodec, null) < 0)
{
Console.WriteLine("can not open codec");
ffmpeg.avcodec_free_context(&mCodecContext);
return;
}
AVCodecParserContext *parser = ffmpeg.av_parser_init((int)AVCodecID.AV_CODEC_ID_H264);
if (parser == null)
{
Console.WriteLine("can not initialize parser");
ffmpeg.avcodec_close(mCodecContext);
ffmpeg.avcodec_free_context(&mCodecContext);
return;
}
//AVFrame用于存储解码后的像素数据(YUV)
//内存分配
AVFrame *pFrame = ffmpeg.av_frame_alloc();
//YUV420
AVFrame *pFrameYUV = ffmpeg.av_frame_alloc();
//只有指定了AVFrame的像素格式、画面大小才能真正分配内存
//缓冲区分配内存
int out_buffer_size = ffmpeg.avpicture_get_size(AVPixelFormat.AV_PIX_FMT_YUV420P, 720, 1280);
byte *out_buffer = (byte *)ffmpeg.av_malloc((ulong)out_buffer_size);
//初始化缓冲区
ffmpeg.avpicture_fill((AVPicture *)pFrameYUV, out_buffer, AVPixelFormat.AV_PIX_FMT_YUV420P, 720, 1280);
//用于转码（缩放）的参数，转之前的宽高，转之后的宽高，格式等
//SwsContext* sws_ctx = ffmpeg.sws_getContext(mCodecContext->width, mCodecContext->height, AVPixelFormat.AV_PIX_FMT_YUV420P /*pCodecCtx->pix_fmt*/, mCodecContext->width, mCodecContext->height, AVPixelFormat.AV_PIX_FMT_YUV420P, ffmpeg.SWS_BICUBIC, null, null, null);
SwsContext *sws_ctx = ffmpeg.sws_getContext(720, 1280, AVPixelFormat.AV_PIX_FMT_YUV420P /*pCodecCtx->pix_fmt*/, 720, 1280, AVPixelFormat.AV_PIX_FMT_YUV420P, ffmpeg.SWS_BICUBIC, null, null, null);
AVPacket packet;
ffmpeg.av_init_packet(&packet);
byte[] inbuffer = new byte[4096];
int cur_size, ret, got_picture;
int readLen = 0;
bool first_time = true;
sdlvideo.SDL_Init(720, 1280);
while (true)
{
readLen = 0;
cur_size = stream.Read(inbuffer, 0, 4096);
if (cur_size <= 0)
{
Console.WriteLine("read eof");
break;
}
while (cur_size > 0)
{
fixed(byte *cur_ptr = inbuffer)
{
int len = ffmpeg.av_parser_parse2(parser, mCodecContext,
&packet.data, &packet.size, cur_ptr + readLen, cur_size,
ffmpeg.AV_NOPTS_VALUE, ffmpeg.AV_NOPTS_VALUE, -1);
readLen += len;
cur_size -= len;
}
if (packet.size == 0)
{
continue;
}
Console.WriteLine($"[Packet]Size:{packet.size}");
ret = ffmpeg.avcodec_decode_video2(mCodecContext, pFrame, &got_picture, &packet);
if (ret < 0)
{
Console.WriteLine("Decode Error.\n");
break;
}
// 读取解码后的帧数据
if (got_picture > 0)
{
if (first_time)
{
Console.WriteLine($"width:{mCodecContext->width}\nheight:{mCodecContext->height}\n\n");
first_time = false;
}
//AVFrame转为像素格式YUV420，宽高
ffmpeg.sws_scale(sws_ctx, pFrame->data, pFrame->linesize, 0, mCodecContext->height, pFrameYUV->data, pFrameYUV->linesize);
//SDL播放YUV数据
var data = out_buffer;
sdlvideo.SDL_Display(mCodecContext->width, mCodecContext->height, (IntPtr)data, out_buffer_size, pFrameYUV->linesize[0]);
}
}
}
Console.WriteLine("exit loop");
ffmpeg.av_parser_close(parser);
ffmpeg.avcodec_close(mCodecContext);
ffmpeg.avcodec_free_context(&mCodecContext);
// todo notify stopped
}
catch (Exception ex)
{
Console.WriteLine("H264SocketParser.thread error:", ex);
}
}
/// <summary>
/// 视频H264转YUV并使用SDL进行播放
/// </summary>
/// <param name="fileName"></param>
/// <param name="sdlVideo"></param>
/// <returns></returns>
public unsafe int RunVideo(string fileName, SDLHelper sdlVideo)
{
IsRun = true;
exit_thread = false;
pause_thread = false;
threadVideo = Thread.CurrentThread;
int error, frame_count = 0;
int got_picture, ret;
SwsContext * pSwsCtx = null;
AVFormatContext *ofmt_ctx = null;
IntPtr convertedFrameBufferPtr = IntPtr.Zero;
try
{
// 注册编解码器
ffmpeg.avcodec_register_all();
// 获取文件信息上下文初始化
ofmt_ctx = ffmpeg.avformat_alloc_context();
// 打开媒体文件
error = ffmpeg.avformat_open_input(&ofmt_ctx, fileName, null, null);
if (error != 0)
{
throw new ApplicationException($"ffmpeg avformat_open_input error {error}");
}
// 获取流的通道
for (int i = 0; i < ofmt_ctx->nb_streams; i++)
{
if (ofmt_ctx->streams[i]->codec->codec_type == AVMediaType.AVMEDIA_TYPE_VIDEO)
{
videoindex = i;
Console.WriteLine("video.............." + videoindex);
}
}
if (videoindex == -1)
{
Console.WriteLine("Couldn't find a video stream.（没有找到视频流）");
return(-1);
}
// 视频流处理
if (videoindex > -1)
{
//获取视频流中的编解码上下文
AVCodecContext *pCodecCtx = ofmt_ctx->streams[videoindex]->codec;
//根据编解码上下文中的编码id查找对应的解码
AVCodec *pCodec = ffmpeg.avcodec_find_decoder(pCodecCtx->codec_id);
if (pCodec == null)
{
Console.WriteLine("没有找到编码器");
return(-1);
}
//打开编码器
if (ffmpeg.avcodec_open2(pCodecCtx, pCodec, null) < 0)
{
Console.WriteLine("编码器无法打开");
return(-1);
}
Console.WriteLine("Find a video stream.channel=" + videoindex);
//输出视频信息
var format = ofmt_ctx->iformat->name->ToString();
var len = (ofmt_ctx->duration) / 1000000;
var width = pCodecCtx->width;
var height = pCodecCtx->height;
Console.WriteLine("video format：" + format);
Console.WriteLine("video length：" + len);
Console.WriteLine("video width&height：width=" + width + " height=" + height);
Console.WriteLine("video codec name：" + pCodec->name->ToString());
//准备读取
//AVPacket用于存储一帧一帧的压缩数据（H264）
//缓冲区，开辟空间
AVPacket *packet = (AVPacket *)ffmpeg.av_malloc((ulong)sizeof(AVPacket));
//AVFrame用于存储解码后的像素数据(YUV)
//内存分配
AVFrame *pFrame = ffmpeg.av_frame_alloc();
//YUV420
AVFrame *pFrameYUV = ffmpeg.av_frame_alloc();
//只有指定了AVFrame的像素格式、画面大小才能真正分配内存
//缓冲区分配内存
int out_buffer_size = ffmpeg.avpicture_get_size(AVPixelFormat.AV_PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
byte *out_buffer = (byte *)ffmpeg.av_malloc((ulong)out_buffer_size);
//初始化缓冲区
ffmpeg.avpicture_fill((AVPicture *)pFrameYUV, out_buffer, AVPixelFormat.AV_PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
//用于转码（缩放）的参数，转之前的宽高，转之后的宽高，格式等
SwsContext *sws_ctx = ffmpeg.sws_getContext(pCodecCtx->width, pCodecCtx->height, AVPixelFormat.AV_PIX_FMT_YUV420P /*pCodecCtx->pix_fmt*/, pCodecCtx->width, pCodecCtx->height, AVPixelFormat.AV_PIX_FMT_YUV420P, ffmpeg.SWS_BICUBIC, null, null, null);
// 初始化sdl
sdlVideo.SDL_Init(pCodecCtx->width, pCodecCtx->height);
while (ffmpeg.av_read_frame(ofmt_ctx, packet) >= 0)
{
// 退出线程
if (exit_thread)
{
break;
}
// 暂停解析
if (pause_thread)
{
while (pause_thread)
{
Thread.Sleep(100);
}
}
//只要视频压缩数据（根据流的索引位置判断）
if (packet->stream_index == videoindex)
{
//解码一帧视频压缩数据，得到视频像素数据
ret = ffmpeg.avcodec_decode_video2(pCodecCtx, pFrame, &got_picture, packet);
if (ret < 0)
{
Console.WriteLine("视频解码错误");
return(-1);
}
// 读取解码后的帧数据
if (got_picture > 0)
{
frame_count++;
Console.WriteLine("视频帧数:第 " + frame_count + " 帧");
//AVFrame转为像素格式YUV420，宽高
ffmpeg.sws_scale(sws_ctx, pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameYUV->data, pFrameYUV->linesize);
//SDL播放YUV数据
var data = out_buffer;
sdlVideo.SDL_Display(pCodecCtx->width, pCodecCtx->height, (IntPtr)data, out_buffer_size, pFrameYUV->linesize[0]);
}
}
//释放资源
ffmpeg.av_free_packet(packet);
}
}
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
finally
{
if (&ofmt_ctx != null)
{
ffmpeg.avformat_close_input(&ofmt_ctx);//关闭流文件
}
}
IsRun = false;
return(0);
}
