func FindDefaultChannelLayout(numberOfChannels int) (ChannelLayout, bool) {
cl := C.av_get_default_channel_layout(C.int(numberOfChannels))
if cl <= 0 {
return 0, false
}
return ChannelLayout(cl), true
}
func (m *Muxer) AddAudioStream(codecId uint32) bool {
codec := C.avcodec_find_encoder(codecId)
if codec == (*C.AVCodec)(null) {
return false
}
m.context.oformat.audio_codec = codecId
stream := C.avformat_new_stream(m.context, codec)
if stream == (*C.AVStream)(null) {
return false
}
m.audioStream = Stream{stream, 0}
c := m.audioStream.stream.codec
c.bit_rate = 48000
c.sample_fmt = C.AV_SAMPLE_FMT_S16
if C.check_sample_fmt(codec, c.sample_fmt) == 0 {
return false
}
c.channels = 1
c.channel_layout = C.uint64_t(C.av_get_default_channel_layout(c.channels))
c.sample_rate = 44100
m.audioStream.stream.time_base = C.AVRational{1, c.sample_rate}
c.time_base = m.audioStream.stream.time_base
if m.context.oformat.flags&C.AVFMT_GLOBALHEADER != 0 {
c.flags |= C.CODEC_FLAG_GLOBAL_HEADER
}
if codecId == C.AV_CODEC_ID_AAC {
m.fifo = C.av_audio_fifo_alloc(c.sample_fmt, c.channels, 1)
if m.fifo == (*C.AVAudioFifo)(null) {
return false
}
m.recl = append(m.recl, func() {
C.av_audio_fifo_free(m.fifo)
})
}
if C.avcodec_open2(c, (*C.AVCodec)(null), (**C.AVDictionary)(null)) < 0 {
return false
}
m.recl = append(m.recl, func() {
C.avcodec_close(c)
})
if c.codec.capabilities&C.CODEC_CAP_VARIABLE_FRAME_SIZE != 0 {
c.frame_size = 10000
}
return true
}