能否提供一个使用CanMv编写的 摄像头输出到IDE显示，同时播放mp4视频的例程

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能否提供一个使用CanMv编写的 摄像头输出到IDE显示，同时播放mp4视频的例程

Lonly1
2 Answers

您好，我们近期会完善 MP4 接口。待这部分完善后，您可以参考相关demo。

sxp123451

您好，已公开kd_mp4系列更底层mp4控制接口，利用这些底层接口函数，您可以结合其他模块，完成更复杂的综合性示例。
以下是一个使用 kd_mp4 底层接口的 MP4 解复用示例。通过该示例，您可以解析 MP4 文件并提取其中的音视频数据。

# MP4 Demuxer Example
#
# This script demuxes an MP4 file, extracting video and audio streams.
# Supported video codecs: H.264, H.265
# Supported audio codecs: G.711A, G.711U

from media.media import *
from mpp.mp4_format import *
from mpp.mp4_format_struct import *
from media.pyaudio import *
import media.g711 as g711
from mpp.payload_struct import *
import media.vdecoder as vdecoder
from media.display import *
import uctypes
import time
import _thread
import os

def demuxer_mp4(filename):
    mp4_cfg = k_mp4_config_s()
    video_info = k_mp4_video_info_s()
    video_track = False
    audio_info = k_mp4_audio_info_s()
    audio_track = False
    mp4_handle = k_u64_ptr()

    mp4_cfg.config_type = K_MP4_CONFIG_DEMUXER
    mp4_cfg.muxer_config.file_name[:] = bytes(filename, 'utf-8')
    mp4_cfg.muxer_config.fmp4_flag = 0

    ret = kd_mp4_create(mp4_handle, mp4_cfg)
    if ret:
        raise OSError("kd_mp4_create failed:",filename)

    file_info = k_mp4_file_info_s()
    kd_mp4_get_file_info(mp4_handle.value, file_info)
    #print("=====file_info: track_num:",file_info.track_num,"duration:",file_info.duration)

    for i in range(file_info.track_num):
        track_info = k_mp4_track_info_s()
        ret = kd_mp4_get_track_by_index(mp4_handle.value, i, track_info)
        if (ret < 0):
            raise ValueError("kd_mp4_get_track_by_index failed")

        if (track_info.track_type == K_MP4_STREAM_VIDEO):
            if (track_info.video_info.codec_id == K_MP4_CODEC_ID_H264 or track_info.video_info.codec_id == K_MP4_CODEC_ID_H265):
                video_track = True
                video_info = track_info.video_info
                print("    codec_id: ", video_info.codec_id)
                print("    track_id: ", video_info.track_id)
                print("    width: ", video_info.width)
                print("    height: ", video_info.height)
            else:
                print("video not support codecid:",track_info.video_info.codec_id)
        elif (track_info.track_type == K_MP4_STREAM_AUDIO):
            if (track_info.audio_info.codec_id == K_MP4_CODEC_ID_G711A or track_info.audio_info.codec_id == K_MP4_CODEC_ID_G711U):
                audio_track = True
                audio_info = track_info.audio_info
                print("    codec_id: ", audio_info.codec_id)
                print("    track_id: ", audio_info.track_id)
                print("    channels: ", audio_info.channels)
                print("    sample_rate: ", audio_info.sample_rate)
                print("    bit_per_sample: ", audio_info.bit_per_sample)
                #audio_info.channels = 2
            else:
                print("audio not support codecid:",track_info.audio_info.codec_id)

    if (video_track == False):
        raise ValueError("video track not found")

    # 记录初始系统时间
    start_system_time = time.ticks_ms()
    # 记录初始视频时间戳
    start_video_timestamp = 0

    while (True):
        frame_data =  k_mp4_frame_data_s()
        ret = kd_mp4_get_frame(mp4_handle.value, frame_data)
        if (ret < 0):
            raise OSError("get frame data failed")

        if (frame_data.eof):
            break

        if (frame_data.codec_id == K_MP4_CODEC_ID_H264 or frame_data.codec_id == K_MP4_CODEC_ID_H265):
            data = uctypes.bytes_at(frame_data.data,frame_data.data_length)
            print("video frame_data.codec_id:",frame_data.codec_id,"data_length:",frame_data.data_length,"timestamp:",frame_data.time_stamp)

            # 计算视频时间戳经历的时长
            video_timestamp_elapsed = frame_data.time_stamp - start_video_timestamp
            # 计算系统时间戳经历的时长
            current_system_time = time.ticks_ms()
            system_time_elapsed = current_system_time - start_system_time

            # 如果系统时间戳经历的时长小于视频时间戳经历的时长，进行延时
            if system_time_elapsed < video_timestamp_elapsed:
                time.sleep_ms(video_timestamp_elapsed - system_time_elapsed)

        elif(frame_data.codec_id == K_MP4_CODEC_ID_G711A or frame_data.codec_id == K_MP4_CODEC_ID_G711U):
            data = uctypes.bytes_at(frame_data.data,frame_data.data_length)
            print("audio frame_data.codec_id:",frame_data.codec_id,"data_length:",frame_data.data_length,"timestamp:",frame_data.time_stamp)

    kd_mp4_destroy(mp4_handle.value)

if __name__ == "__main__":
    os.exitpoint(os.EXITPOINT_ENABLE)
    demuxer_mp4("/sdcard/examples/test.mp4")
sxp123451