com.github.xingshuangs.iot.protocol.mp4.model.Mp4AvcCBox Maven / Gradle / Ivy
package com.github.xingshuangs.iot.protocol.mp4.model;
import com.github.xingshuangs.iot.protocol.common.buff.ByteWriteBuff;
import com.github.xingshuangs.iot.protocol.mp4.enums.EMp4Type;
/**
* Sample Description Box(stbl-stsd)，存放解码必须的描述信息,其也是一个container box，对于H264码流来说其包含avc1子box
*
* @author xingshuang
*/
public class Mp4AvcCBox extends Mp4Box {
/**
* 1字节，版本
*/
private final int version;
/**
* 1字节profile
*/
private final int profile;
/**
* 1字节compat
*/
private final int profileCompat;
/**
* 1字节level
*/
private final int level;
/**
* 1字节nalu长度头字节数, 此位标识nalu去掉起始位后，前面多少位用来表示nalu长度，此字节前五位默认为1,
* 后三位值+1表示帧size占用的字节数，我们用4个字节来存储帧大小，所以这里为3，即为0xFC|0x03=0xFF
*/
private final int lengthSizeMinusOne;
/**
* 1字节sps个数，前3位预留，默认位1，后五位表示sps个数，我们只放了一个sps，因此为E0|01=E1
*/
private final int spsCount;
/**
* 2字节sps帧长度
*/
private final int spsLength;
/**
* sps内容
*/
private final byte[] sps;
/**
* 1字节pps个数
*/
private final int ppsCount;
/**
* 2字节pps帧长度
*/
private final int ppsLength;
/**
* pps内容
*/
private final byte[] pps;
public Mp4AvcCBox(Mp4TrackInfo trackInfo) {
this.mp4Type = EMp4Type.AVCC;
this.version = 1;
this.profile = trackInfo.getSps()[1];
this.profileCompat = trackInfo.getSps()[2];
this.level = trackInfo.getSps()[3];
this.lengthSizeMinusOne = 0xFF;
this.spsCount = 0xE1;
this.spsLength = trackInfo.getSps().length;
this.sps = trackInfo.getSps();
this.ppsCount = 1;
this.ppsLength = trackInfo.getPps().length;
this.pps = trackInfo.getPps();
}
@Override
public int byteArrayLength() {
return 19 + this.spsLength + this.ppsLength;
}
@Override
public byte[] toByteArray() {
int size = this.byteArrayLength();
return ByteWriteBuff.newInstance(size)
.putInteger(size)
.putBytes(this.mp4Type.getByteArray())
.putByte(this.version)
.putByte(this.profile)
.putByte(this.profileCompat)
.putByte(this.level)
.putByte(this.lengthSizeMinusOne)
.putByte(this.spsCount)
.putShort(this.spsLength)
.putBytes(this.sps)
.putByte(this.ppsCount)
.putShort(this.ppsLength)
.putBytes(this.pps)
.getData();
}
}