4. Video例程讲解

1. 概述

K230 支持对视频流进行 H264 或 H265 编码，CanMV 中提供的 API 使用户能够进行 MP4 文件的录制与播放，同时支持 RTSP 推流。

2. 示例

2.1 MP4录制

本示例程序用于在 CanMV 开发板进行 mp4 muxer 的功能展示。

# Save MP4 file example
#
# Note: You will need an SD card to run this example.
#
# You can capture audio and video and save them as MP4.The current version only supports MP4 format, video supports 264/265, and audio supports g711a/g711u.

from media.mp4format import *
import os

def mp4_muxer_test():
    print("mp4_muxer_test start")
    width = 1280
    height = 720
    # 实例化mp4 container
    mp4_muxer = Mp4Container()
    mp4_cfg = Mp4CfgStr(mp4_muxer.MP4_CONFIG_TYPE_MUXER)
    if mp4_cfg.type == mp4_muxer.MP4_CONFIG_TYPE_MUXER:
        file_name = "/sdcard/examples/test.mp4"
        mp4_cfg.SetMuxerCfg(file_name, mp4_muxer.MP4_CODEC_ID_H265, width, height, mp4_muxer.MP4_CODEC_ID_G711U)
    # 创建mp4 muxer
    mp4_muxer.Create(mp4_cfg)
    # 启动mp4 muxer
    mp4_muxer.Start()

    frame_count = 0
    try:
        while True:
            os.exitpoint()
            # 处理音视频数据，按MP4格式写入文件
            mp4_muxer.Process()
            frame_count += 1
            print("frame_count = ", frame_count)
            if frame_count >= 200:
                break
    except BaseException as e:
        print(e)
    # 停止mp4 muxer
    mp4_muxer.Stop()
    # 销毁mp4 muxer
    mp4_muxer.Destroy()
    print("mp4_muxer_test stop")

if __name__ == "__main__":
    os.exitpoint(os.EXITPOINT_ENABLE)
    mp4_muxer_test()

提示

具体接口定义请参考 player

2.2 MP4播放

本示例程序用于对 CanMV 开发板进行一个 mp4 文件播放器的功能展示。

# play mp4 file example
#
# Note: You will need an SD card to run this example.
#
# You can load local files to play. The current version only supports MP4 format, video supports 264/265, and audio supports g711a/g711u.

from media.player import * #导入播放器模块，用于播放mp4文件
import os

start_play = False #播放结束flag
def player_event(event,data):
    global start_play
    if(event == K_PLAYER_EVENT_EOF): #播放结束标识
        start_play = False #设置播放结束标识

def play_mp4_test(filename):
    global start_play
    # player=Player() #创建播放器对象
    # 使用IDE作为输出显示，可以设定任意分辨率
    player=Player(Display.VIRT)
    # 使用ST7701 LCD屏幕作为输出显示，最大分辨率800*480
    # player=Player(Display.ST7701)
    # 使用HDMI作为输出显示
    # player=Player(Display.LT9611)
    player.load(filename) #加载mp4文件
    player.set_event_callback(player_event) #设置播放器事件回调
    player.start() #开始播放
    start_play = True

    #等待播放结束
    try:
        while(start_play):
            time.sleep(0.1)
            os.exitpoint()
    except KeyboardInterrupt as e:
        print("user stop: ", e)
    except BaseException as e:
        sys.print_exception(e)

    player.stop() #停止播放
    print("play over")

if __name__ == "__main__":
    os.exitpoint(os.EXITPOINT_ENABLE)
    play_mp4_test("/sdcard/examples/test.mp4")#播放mp4文件

提示

具体接口定义请参考 player

2.3 H264/H265编码

本示例程序用于在 CanMV 开发板进行 venc 视频编码的功能展示。

# Video encode example
#
# Note: You will need an SD card to run this example.
#
# You can capture videos and encode them into 264/265 files

from media.vencoder import *
from media.sensor import *
from media.media import *
import time, os

def vi_bind_venc_test(file_name,width=1280, height=720):
    print("venc_test start")
    venc_chn = VENC_CHN_ID_0
    width = ALIGN_UP(width, 16)
    venc_payload_type = K_PT_H264

    # 判断文件类型
    suffix = file_name.split('.')[-1]
    if suffix == '264':
        venc_payload_type = K_PT_H264
    elif suffix == '265':
        venc_payload_type = K_PT_H265
    else:
        print("Unknown file extension")
        return

    # 初始化sensor
    sensor = Sensor()
    sensor.reset()
    # 设置camera 输出buffer
    # set chn0 output size
    sensor.set_framesize(width = width, height = height, alignment=12)
    # set chn0 output format
    sensor.set_pixformat(Sensor.YUV420SP)


    # 实例化video encoder
    encoder = Encoder()
    # 设置video encoder 输出buffer
    encoder.SetOutBufs(venc_chn, 8, width, height)

    # 绑定camera和venc
    link = MediaManager.link(sensor.bind_info()['src'], (VIDEO_ENCODE_MOD_ID, VENC_DEV_ID, venc_chn))

    # init media manager
    MediaManager.init()

    if (venc_payload_type == K_PT_H264):
        chnAttr = ChnAttrStr(encoder.PAYLOAD_TYPE_H264, encoder.H264_PROFILE_MAIN, width, height)
    elif (venc_payload_type == K_PT_H265):
        chnAttr = ChnAttrStr(encoder.PAYLOAD_TYPE_H265, encoder.H265_PROFILE_MAIN, width, height)

    streamData = StreamData()

    # 创建编码器
    encoder.Create(venc_chn, chnAttr)

    # 开始编码
    encoder.Start(venc_chn)
    # 启动camera
    sensor.run()

    frame_count = 0
    print("save stream to file: ", file_name)

    with open(file_name, "wb") as fo:
        try:
            while True:
                os.exitpoint()
                encoder.GetStream(venc_chn, streamData) # 获取一帧码流

                for pack_idx in range(0, streamData.pack_cnt):
                    stream_data = uctypes.bytearray_at(streamData.data[pack_idx], streamData.data_size[pack_idx])
                    fo.write(stream_data) # 码流写文件
                    print("stream size: ", streamData.data_size[pack_idx], "stream type: ", streamData.stream_type[pack_idx])

                encoder.ReleaseStream(venc_chn, streamData) # 释放一帧码流

                frame_count += 1
                if frame_count >= 200:
                    break
        except KeyboardInterrupt as e:
            print("user stop: ", e)
        except BaseException as e:
            import sys
            sys.print_exception(e)

    # 停止camera
    sensor.stop()
    # 销毁camera和venc的绑定
    del link
    # 停止编码
    encoder.Stop(venc_chn)
    # 销毁编码器
    encoder.Destroy(venc_chn)
    # 清理buffer
    MediaManager.deinit()
    print("venc_test stop")

def stream_venc_test(file_name,width=1280, height=720):
    print("venc_test start")
    venc_chn = VENC_CHN_ID_0
    width = ALIGN_UP(width, 16)
    venc_payload_type = K_PT_H264

    # 判断文件类型
    suffix = file_name.split('.')[-1]
    if suffix == '264':
        venc_payload_type = K_PT_H264
    elif suffix == '265':
        venc_payload_type = K_PT_H265
    else:
        print("Unknown file extension")
        return

    # 初始化sensor
    sensor = Sensor()
    sensor.reset()
    # 设置camera 输出buffer
    # set chn0 output size
    sensor.set_framesize(width = width, height = height, alignment=12)
    # set chn0 output format
    sensor.set_pixformat(Sensor.YUV420SP)


    # 实例化video encoder
    encoder = Encoder()
    # 设置video encoder 输出buffer
    encoder.SetOutBufs(venc_chn, 8, width, height)

    # init media manager
    MediaManager.init()

    if (venc_payload_type == K_PT_H264):
        chnAttr = ChnAttrStr(encoder.PAYLOAD_TYPE_H264, encoder.H264_PROFILE_MAIN, width, height)
    elif (venc_payload_type == K_PT_H265):
        chnAttr = ChnAttrStr(encoder.PAYLOAD_TYPE_H265, encoder.H265_PROFILE_MAIN, width, height)

    streamData = StreamData()

    # 创建编码器
    encoder.Create(venc_chn, chnAttr)

    # 开始编码
    encoder.Start(venc_chn)
    # 启动camera
    sensor.run()

    frame_count = 0
    print("save stream to file: ", file_name)

    yuv420sp_img = None
    frame_info = k_video_frame_info()
    with open(file_name, "wb") as fo:
        try:
            while True:
                os.exitpoint()
                yuv420sp_img = sensor.snapshot(chn=CAM_CHN_ID_0)
                if (yuv420sp_img == -1):
                    continue

                frame_info.v_frame.width = yuv420sp_img.width()
                frame_info.v_frame.height = yuv420sp_img.height()
                frame_info.v_frame.pixel_format = Sensor.YUV420SP
                frame_info.pool_id = yuv420sp_img.poolid()
                frame_info.v_frame.phys_addr[0] = yuv420sp_img.phyaddr()
                #frame_info.v_frame.phys_addr[1] = yuv420sp_img.phyaddr(1)
                if (yuv420sp_img.width() == 800 and yuv420sp_img.height() == 480):
                    frame_info.v_frame.phys_addr[1] = frame_info.v_frame.phys_addr[0] + frame_info.v_frame.width*frame_info.v_frame.height + 1024
                elif (yuv420sp_img.width() == 1920 and yuv420sp_img.height() == 1080):
                    frame_info.v_frame.phys_addr[1] = frame_info.v_frame.phys_addr[0] + frame_info.v_frame.width*frame_info.v_frame.height + 3072
                elif (yuv420sp_img.width() == 640 and yuv420sp_img.height() == 360):
                    frame_info.v_frame.phys_addr[1] = frame_info.v_frame.phys_addr[0] + frame_info.v_frame.width*frame_info.v_frame.height + 3072
                else:
                    frame_info.v_frame.phys_addr[1] = frame_info.v_frame.phys_addr[0] + frame_info.v_frame.width*frame_info.v_frame.height


                encoder.SendFrame(venc_chn,frame_info)
                encoder.GetStream(venc_chn, streamData) # 获取一帧码流

                for pack_idx in range(0, streamData.pack_cnt):
                    stream_data = uctypes.bytearray_at(streamData.data[pack_idx], streamData.data_size[pack_idx])
                    fo.write(stream_data) # 码流写文件
                    print("stream size: ", streamData.data_size[pack_idx], "stream type: ", streamData.stream_type[pack_idx])

                encoder.ReleaseStream(venc_chn, streamData) # 释放一帧码流

                frame_count += 1
                if frame_count >= 200:
                    break
        except KeyboardInterrupt as e:
            print("user stop: ", e)
        except BaseException as e:
            import sys
            sys.print_exception(e)

    # 停止camera
    sensor.stop()
    # 停止编码
    encoder.Stop(venc_chn)
    # 销毁编码器
    encoder.Destroy(venc_chn)
    # 清理buffer
    MediaManager.deinit()
    print("venc_test stop")

if __name__ == "__main__":
    os.exitpoint(os.EXITPOINT_ENABLE)
    vi_bind_venc_test("/sdcard/examples/test.264",800,480)  # vi绑定venc示例
    #stream_venc_test("/sdcard/examples/test.264",800,480)  # venc编码数据流示例

提示

具体接口定义请参考 VENC

2.4 H264/H265解码

本示例程序用于在 CanMV 开发板进行 vdec 视频解码的功能展示。

# Video encode example
#
# Note: You will need an SD card to run this example.
#
# You can decode 264/265 and display them on the screen

from media.media import *
from mpp.payload_struct import *
import media.vdecoder as vdecoder
from media.display import *

import time, os

STREAM_SIZE = 40960
def vdec_test(file_name,width=1280,height=720):
    print("vdec_test start")
    vdec_chn = VENC_CHN_ID_0
    vdec_width =  ALIGN_UP(width, 16)
    vdec_height = height
    vdec = None
    vdec_payload_type = K_PT_H264

    #display_type = Display.VIRT
    display_type = Display.ST7701 #使用ST7701 LCD屏作为输出显示，最大分辨率800*480
    #display_type = Display.LT9611 #使用HDMI作为输出显示

    # 判断文件类型
    suffix = file_name.split('.')[-1]
    if suffix == '264':
        vdec_payload_type = K_PT_H264
    elif suffix == '265':
        vdec_payload_type = K_PT_H265
    else:
        print("Unknown file extension")
        return

    # 实例化video decoder
    #vdecoder.Decoder.vb_pool_config(4,6)
    vdec = vdecoder.Decoder(vdec_payload_type)

    # 初始化display
    if (display_type == Display.VIRT):
        Display.init(display_type,width = vdec_width, height = vdec_height,fps=30)
    else:
        Display.init(display_type,to_ide = True)

    #vb buffer初始化
    MediaManager.init()

    # 创建video decoder
    vdec.create()

    # vdec bind display
    bind_info = vdec.bind_info(width=vdec_width,height=vdec_height,chn=vdec.get_vdec_channel())
    Display.bind_layer(**bind_info, layer = Display.LAYER_VIDEO1)

    vdec.start()
    # 打开文件
    with open(file_name, "rb") as fi:
        while True:
            os.exitpoint()
            # 读取视频数据流
            data = fi.read(STREAM_SIZE)
            if not data:
                break
            # 解码数据流
            vdec.decode(data)

    # 停止video decoder
    vdec.stop()
    # 销毁video decoder
    vdec.destroy()
    time.sleep(1)

    # 关闭display
    Display.deinit()
    # 释放vb buffer
    MediaManager.deinit()

    print("vdec_test stop")


if __name__ == "__main__":
    os.exitpoint(os.EXITPOINT_ENABLE)
    vdec_test("/sdcard/examples/test.264",800,480) #解码264/265视频文件

提示

具体接口定义请参考 VDEC

2.5 RTSP推流

这个示例演示了如何使用RTSP服务器将视频和音频流式传输到网络。

# Description: This example demonstrates how to stream video and audio to the network using the RTSP server.
#
# Note: You will need an SD card to run this example.
#
# You can run the rtsp server to stream video and audio to the network

from media.vencoder import *
from media.sensor import *
from media.media import *
import time, os
import _thread
import multimedia as mm
from time import *

class RtspServer:
    def __init__(self,session_name="test",port=8554,video_type = mm.multi_media_type.media_h264,enable_audio=False):
        self.session_name = session_name # session name
        self.video_type = video_type  # 视频类型264/265
        self.enable_audio = enable_audio # 是否启用音频
        self.port = port   #rtsp 端口号
        self.rtspserver = mm.rtsp_server() # 实例化rtsp server
        self.venc_chn = VENC_CHN_ID_0 #venc通道
        self.start_stream = False #是否启动推流线程
        self.runthread_over = False #推流线程是否结束

    def start(self):
        # 初始化推流
        self._init_stream()
        self.rtspserver.rtspserver_init(self.port)
        # 创建session
        self.rtspserver.rtspserver_createsession(self.session_name,self.video_type,self.enable_audio)
        # 启动rtsp server
        self.rtspserver.rtspserver_start()
        self._start_stream()

        # 启动推流线程
        self.start_stream = True
        _thread.start_new_thread(self._do_rtsp_stream,())


    def stop(self):
        if (self.start_stream == False):
            return
        # 等待推流线程退出
        self.start_stream = False
        while not self.runthread_over:
            sleep(0.1)
        self.runthread_over = False

        # 停止推流
        self._stop_stream()
        self.rtspserver.rtspserver_stop()
        #self.rtspserver.rtspserver_destroysession(self.session_name)
        self.rtspserver.rtspserver_deinit()

    def get_rtsp_url(self):
        return self.rtspserver.rtspserver_getrtspurl(self.session_name)

    def _init_stream(self):
        width = 1280
        height = 720
        width = ALIGN_UP(width, 16)
        # 初始化sensor
        self.sensor = Sensor()
        self.sensor.reset()
        self.sensor.set_framesize(width = width, height = height, alignment=12)
        self.sensor.set_pixformat(Sensor.YUV420SP)
        # 实例化video encoder
        self.encoder = Encoder()
        self.encoder.SetOutBufs(self.venc_chn, 8, width, height)
        # 绑定camera和venc
        self.link = MediaManager.link(self.sensor.bind_info()['src'], (VIDEO_ENCODE_MOD_ID, VENC_DEV_ID, self.venc_chn))
        # init media manager
        MediaManager.init()
        # 创建编码器
        chnAttr = ChnAttrStr(self.encoder.PAYLOAD_TYPE_H264, self.encoder.H264_PROFILE_MAIN, width, height)
        self.encoder.Create(self.venc_chn, chnAttr)

    def _start_stream(self):
        # 开始编码
        self.encoder.Start(self.venc_chn)
        # 启动camera
        self.sensor.run()

    def _stop_stream(self):
        # 停止camera
        self.sensor.stop()
        # 接绑定camera和venc
        del self.link
        # 停止编码
        self.encoder.Stop(self.venc_chn)
        self.encoder.Destroy(self.venc_chn)
        # 清理buffer
        MediaManager.deinit()

    def _do_rtsp_stream(self):
        try:
            streamData = StreamData()
            while self.start_stream:
                os.exitpoint()
                # 获取一帧码流
                self.encoder.GetStream(self.venc_chn, streamData)
                # 推流
                for pack_idx in range(0, streamData.pack_cnt):
                    stream_data = bytes(uctypes.bytearray_at(streamData.data[pack_idx], streamData.data_size[pack_idx]))
                    self.rtspserver.rtspserver_sendvideodata(self.session_name,stream_data, streamData.data_size[pack_idx],1000)
                    #print("stream size: ", streamData.data_size[pack_idx], "stream type: ", streamData.stream_type[pack_idx])
                # 释放一帧码流
                self.encoder.ReleaseStream(self.venc_chn, streamData)

        except BaseException as e:
            print(f"Exception {e}")
        finally:
            self.runthread_over = True
            # 停止rtsp server
            self.stop()

        self.runthread_over = True

if __name__ == "__main__":
    os.exitpoint(os.EXITPOINT_ENABLE)
    # 创建rtsp server对象
    rtspserver = RtspServer()
    # 启动rtsp server
    rtspserver.start()
    # 打印rtsp url
    print("rtsp server start:",rtspserver.get_rtsp_url())
    # 推流60s
    sleep(60)
    # 停止rtsp server
    rtspserver.stop()
    print("done")

提示

具体接口定义请参考 RTSP