Create Matroska audio/video from raw data

[felicemarra]

I successfully wrote the code to create a mp4 from a raw audio/video source

But if something happens during recording, I loose everything because mp4 is corrupted and unrecoverable.

So I need to write a mkv file but there something wrong with initialization. Can you help me?

I just changed format_name: 'mp4' to format_name: 'matroska' and filename from mp4 to mkv.
Note : the original code for mp4 is working well.

`
let encParamsVideo = {
name: 'h264_nvenc',
width: config.width,
height: config.height,
bit_rate: 20000000,
time_base: [1, 30],
framerate: [30, 1],
gop_size: 60,
max_b_frames: 0,
pix_fmt: 'yuv420p',
}

let encParamsAudio = {
    name: 'libfdk_aac',
    time_base: [1, 48000],
    sample_fmt: 's16',
    sample_rate: 48000,
    channels: 1,
    channel_layout: 'mono',
    profile: 'LC'
}

let encoderVideo = await beamcoder.encoder(encParamsVideo)
let encoderAudio = await beamcoder.encoder(encParamsAudio)

encoderAudio.priv_data = { vbr: 3 }

const muxer = beamcoder.muxer({ format_name: 'matroska', tune: 'film' })

muxer.interleaved = false

let vstr = muxer.newStream({
    name: 'h264_nvenc',
    time_base: [1, 90000],
    interleaved: false
})
Object.assign(vstr.codecpar, {
    width: config.width,
    height: config.height,
    format: 'yuv420p',
    bit_rate: 10000000
})

let astr = muxer.newStream({
    time_base: [1, 90000],
    name: 'aac',
    interleaved: true
})

Object.assign(astr.codecpar, {
    extradata: encoderAudio.extradata,
    name: 'aac',
    sample_rate: 48000,
    format: 'flt',
    frame_size: 1024,
    channels: 1,
    channel_layout: 'mono',

    bit_rate: 192000
})

await muxer.openIO({
    url: 'file:.\\record\\output_' + Date.now() + '.mkv'
})

await muxer.writeHeader()

`