AAC ADTS for AACObject ELD packets

Question

How to correctly configure AAC ADTS header to support AAC ELD in Android. I am able to configure for LC and Main.

As per the article below
https://wiki.multimedia.cx/index.php?title=ADTS

Profile take only two bits ( E 2 profile, the MPEG-4 Audio Object Type minus 1) but for profile value for AACObjectELD is 39 ie: 0010 0110

private void addADTStoPacket(byte[] packet, int packetLen) {
    int profile = 39; // 2 - AAC LC,  39 = MediaCodecInfo.CodecProfileLevel.AACObjectELD;
    int freqIdx = 8;  // 4 44.1KHz 8 16KHZ
    int chanCfg = 2;  //2 channel 

    // fill in ADTS data
    packet[0] = (byte)0xFF;
    packet[1] = (byte)0xF1;
    packet[2] = (byte)(((profile-1)<<6) + (freqIdx<<2) +(chanCfg>>2));
    packet[3] = (byte)(((chanCfg&3)<<6) + (packetLen>>11));
    packet[4] = (byte)((packetLen&0x7FF) >> 3);
    packet[5] = (byte)(((packetLen&7)<<5) + 0x1F);
    packet[6] = (byte)0xFC;
}

Kindly request your help.

Thanks in advance
Joseph

Answer 1

i'm sorry you can't do that. adts only support aac main/lc profile.

if yout want support aac-ld aac-eld.you must use mp4. the usual aac frame_size is 1024.960 is for radio brocasting,the aac-ld and eld is 960 480.