在Android程序中获取avc中的数据

在Android程序中获取avc中的数据，也就是AVCDecoderConfigurationRecord 。

你可以先录制一小段视频保存在sd卡中。

然后根据以下代码来获取数据。这样就可以根据不同的手机或者不同的分辨率来调整sps pps或者avc了

package com.ppmeet.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

/**
 * class name：MyDetect<BR>
 * class description：动态获取avc中的数据<BR>
 * PS： <BR>
 *
 * @version 1.00 2011/10/21
 * @author CODYY)peijiangping
 */
public class MyDetect {
    final static int MAX_HEADER_LENGTH = 128;
    public static int mdataPosition = 32;
    private static byte[] checkBuffer = new byte[1024 * 4];
    public static byte[] avcdata = null;

    public static boolean checkMP4_MOOV(String fileName) throws IOException {
        File fin = new File(fileName);
        if (fin.isFile()) {
            InputStream is = new FileInputStream(fin.getAbsolutePath());
            int pos;
            int fms = 0;
            boolean isOK;
            int n;
            while (true) {
                isOK = false;
                n = is.read(checkBuffer);
                if (n < 0) {
                    break;
                }
                for (pos = 0; pos < n; pos++) {
                    byte tmp = checkBuffer[pos];
                    switch (tmp) {
                    case (byte) 'a':
                        if (fms == 0)
                            fms = 1;
                        else
                            fms = 0;
                        break;

                    case (byte) 'v':
                        if (fms == 1)
                            fms = 2;
                        else
                            fms = 0;
                        break;
                    case (byte) 'c':
                        if (fms == 2)
                            fms = 3;
                        else
                            fms = 0;
                        break;
                    case (byte) 'C':
                        if (fms == 3)
                            fms = 4;
                        else
                            fms = 0;
                        break;
                    case (byte) 0x01:
                        if (fms == 4)
                            fms = 5;
                        else
                            fms = 0;
                        break;
                    default:
                        fms = 0;
                        break;
                    }
                    if (fms == 5) {
                        isOK = true;
                        break;
                    }
                }
                if (isOK) {
                    for (int i = 0; i < checkBuffer.length - pos; i++) {
                        checkBuffer[i] = checkBuffer[i + pos];
                    }
                    if (pos > checkBuffer.length - MAX_HEADER_LENGTH) {
                        is.read(checkBuffer, checkBuffer.length - pos,
                                MAX_HEADER_LENGTH);
                    }
                    getAVCData(checkBuffer);
                    return true;
                }
            }
        }
        return false;
    }

    private static byte[] getAVCData(byte[] avc) {
        int avcsize = 0;
        for (int index = 0; index < avc.length; index++) {
            for (int i = 0; i < avc.length; i++) {
                if (i > 31 && avc[i] == 0) {
                    avcsize = i;
                    break;
                }
            }
            avcdata = new byte[avcsize];
            System.arraycopy(avc, 0, avcdata, 0, avcsize);
        }
        return avcdata;
    }
}