Windows平台RTSP|RTMP播放器如何实现实时录像功能

技术背景

RTSP、RTMP直播播放，这里不再赘述，我们可以很轻松的实现毫秒级的延迟体验，这里讲的是如何实现RTSP、RTSP流的实时录像功能。

我们理解的录像，可能觉得，只要有个开始录像、停止录像接口就够了，实际上的录像，如果需要细粒度设计，需要支持设置录像保存路径、开始录像停止录像录像状态回调、录像文件名是不是需要添加时间或前缀（便于查询遍历）、PCMA|PCMU|Speex的audio是不是要转AAC后保存、是不是只录制纯音频或纯视频、单个文件大小等。

技术设计

无图无真相，先说设置界面：

对应的代码如下：

/** RecordConfigForm.cs.cs* Created by daniusdk.com on 2017/04/19.* WeChat: xinsheng120*/using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;namespace SmartPlayer
{public partial class RecordConfigForm : Form{private bool is_rec_video_ = true;private bool is_rec_audio_ = true;private String rec_dir_ = "";private String rec_name_file_prefix_ = "";private UInt32 max_file_size_ = 200 * 1024; // 单位是KByte, 默认200MBprivate bool is_append_date_ = true;private bool is_append_time_ = true;private bool is_audio_transcode_aac_ = true;public bool IsRecVideo() { return is_rec_video_; }public bool IsRecAudio() { return is_rec_audio_; }public String RecDir() { return rec_dir_; }public String RecNameFilePrefix() { return rec_name_file_prefix_; }public UInt32 MaxFileSize() { return max_file_size_; }public bool IsAppendDate() { return is_append_date_; }public bool IsAppendTime() { return is_append_time_; }public bool IsAudioTanscodeAAC() { return is_audio_transcode_aac_; }public RecordConfigForm(bool is_rec_video, bool is_rec_audio, String rec_dir, String rec_name_file_prefix, UInt32 max_file_size, bool is_append_date, bool is_append_time, bool is_audio_transcode_aac){InitializeComponent();text_rec_max_file_size.Text = "200";if (is_rec_video){checkbox_rec_video.CheckState = CheckState.Checked;}else{checkbox_rec_video.CheckState = CheckState.Unchecked;}if (is_rec_audio){checkbox_rec_audio.CheckState = CheckState.Checked;}else{checkbox_rec_audio.CheckState = CheckState.Unchecked;}text_rec_dir.Text = rec_dir;text_rec_name_file_prefix.Text = rec_name_file_prefix;text_rec_max_file_size.Text = (max_file_size/1024).ToString();if (is_append_date){checkbox_append_date.CheckState = CheckState.Checked;}else{checkbox_append_date.CheckState = CheckState.Unchecked;}if (is_append_time){checkbox_append_time.CheckState = CheckState.Checked;}else{checkbox_append_time.CheckState = CheckState.Unchecked;}if (is_audio_transcode_aac){check_rec_audio_transcode_aac.CheckState = CheckState.Checked;}else{check_rec_audio_transcode_aac.CheckState = CheckState.Unchecked;}}private void btn_record_dir_Click(object sender, EventArgs e){FolderBrowserDialog dlg = new FolderBrowserDialog();if (dlg.ShowDialog() == DialogResult.OK){text_rec_dir.Text = dlg.SelectedPath.ToString();}}private void btn_ok_Click(object sender, EventArgs e){is_rec_video_ = checkbox_rec_video.Checked;is_rec_audio_ = checkbox_rec_audio.Checked;rec_dir_ = text_rec_dir.Text;rec_name_file_prefix_ = text_rec_name_file_prefix.Text;max_file_size_ = UInt32.Parse(text_rec_max_file_size.Text)*1024;is_append_date_ = checkbox_append_date.Checked;is_append_time_ = checkbox_append_time.Checked;is_audio_transcode_aac_ = check_rec_audio_transcode_aac.Checked;this.Close();this.Dispose();}private void btn_cancel_Click(object sender, EventArgs e){this.Close();this.Dispose();}}
}

录像设置按钮如下：

private void btn_record_config_Click(object sender, EventArgs e)
{RecordConfigForm record_config_dlg = new RecordConfigForm(is_rec_video_, is_rec_audio_, rec_dir_, rec_name_file_prefix_, max_file_size_, is_append_date_, is_append_time_, is_audio_transcode_aac_);record_config_dlg.ShowDialog();String rec_dir = record_config_dlg.RecDir();if (!String.IsNullOrEmpty(rec_dir)){rec_dir_ = rec_dir;}else{MessageBox.Show("未设置录像保存路径，默认保存到rec文件夹下..");}is_rec_video_ = record_config_dlg.IsRecVideo();is_rec_audio_ = record_config_dlg.IsRecAudio();rec_name_file_prefix_ = record_config_dlg.RecNameFilePrefix();max_file_size_ = record_config_dlg.MaxFileSize();is_append_date_ = record_config_dlg.IsAppendDate();is_append_time_ = record_config_dlg.IsAppendTime();is_audio_transcode_aac_ = record_config_dlg.IsAudioTanscodeAAC();
}

开始录像、结束录像设计如下：

/** SmartPlayerForm.cs.cs* Created by daniusdk.com on 2017/04/19.* WeChat: xinsheng120*/private void btn_record_Click(object sender, EventArgs e)
{if (player_handle_ == IntPtr.Zero)return;if (btn_record.Text == "录像"){if (!is_rec_video_ && !is_rec_audio_){MessageBox.Show("音频录制选项和视频录制选项至少需要选择一个!");return;}if (!is_playing_){if (!InitCommonSDKParam()){MessageBox.Show("设置参数错误!");return;}}NTSmartPlayerSDK.NT_SP_SetRecorderVideo(player_handle_, is_rec_video_ ? 1 : 0);NTSmartPlayerSDK.NT_SP_SetRecorderAudio(player_handle_, is_rec_audio_ ? 1 : 0);UInt32 ret = NTSmartPlayerSDK.NT_SP_SetRecorderDirectoryW(player_handle_, rec_dir_);if (NT.NTBaseCodeDefine.NT_ERC_OK != ret){MessageBox.Show("设置录像目录失败");return;}NTSmartPlayerSDK.NT_SP_SetRecorderFileMaxSize(player_handle_, max_file_size_);NT_SP_RecorderFileNameRuler rec_name_ruler = new NT_SP_RecorderFileNameRuler();rec_name_ruler.type_ = 0;rec_name_ruler.file_name_prefix_ = rec_name_file_prefix_;rec_name_ruler.append_date_ = is_append_date_ ? 1 : 0;rec_name_ruler.append_time_ = is_append_time_ ? 1 : 0;NTSmartPlayerSDK.NT_SP_SetRecorderFileNameRuler(player_handle_, ref rec_name_ruler);record_call_back_ = new SP_SDKRecorderCallBack(SDKRecorderCallBack);NTSmartPlayerSDK.NT_SP_SetRecorderCallBack(player_handle_, IntPtr.Zero, record_call_back_);NTSmartPlayerSDK.NT_SP_SetRecorderAudioTranscodeAAC(player_handle_, is_audio_transcode_aac_ ? 1 : 0);if (NT.NTBaseCodeDefine.NT_ERC_OK != NTSmartPlayerSDK.NT_SP_StartRecorder(player_handle_)){MessageBox.Show("录像失败!");return;}btn_record.Text = "停止录像";is_recording_ = true;}else{StopRecorder();}
}

录像状态回调处理如下，包含了开始录像回调和单个文件录制结束回调：

public void SDKRecorderCallBack(IntPtr handle, IntPtr userData, UInt32 status, [MarshalAs(UnmanagedType.LPStr)] String file_name)
{if (playWnd.InvokeRequired){BeginInvoke(set_record_call_back_, status, file_name);}else{set_record_call_back_(status, file_name);}
}private void RecordCallBack(UInt32 status, [MarshalAs(UnmanagedType.LPStr)] String file_name)
{byte[] utf8_bytes = Encoding.Default.GetBytes(file_name);byte[] default_bytes = Encoding.Convert(Encoding.UTF8, Encoding.Default, utf8_bytes);String recorder_file_name = Encoding.Default.GetString(default_bytes);StringBuilder sb = new StringBuilder();sb.Append("录像状态：");if (status == 1){sb.Append("new file: ");}else if(status == 2){sb.Append("finished file: ");}sb.Append(recorder_file_name);MessageBox.Show(sb.ToString());
}

总结

以上是Windows平台RTSP、RTMP播放器实时录像接口设计，实际上，除了Windows平台，我们Linux、Android、iOS平台也是一样的设计，单纯的录像模块，如果做的全面，也不是一两个接口可以搞定的，此外，录像设计，需要和RTSP|RTMP拉流播放设计，可以做到一起，也可以拆分使用，如果同时录像和直播播放，要注意的是，这时候只需要在一个实例操作，不要播放一个实例，录像一个实例，造成下载两路试试RTSP|RTMP流下来。