编程语言
首页 > 编程语言> > H264 SPS中得到宽高的代码(java)

H264 SPS中得到宽高的代码(java)

作者:互联网

数据需要去掉头,SPS测试数据 byte[] buffer = new byte[]{103, 66, -64, 12, -38, 5, 7, -56, 7, -124, 2} 得到结果宽320高240.

public class H264SpsParser {
    private final static String TAG = H264SpsParser.class.getCanonicalName();
    private final static int NAL_HEADER = 0;

    private static int nStartBit = 0;


    private static int Ue(byte[] pBuff, int nLen) {
        int nZeroNum = 0;
        while (nStartBit < nLen * 8) {
            if ((pBuff[nStartBit / 8] & (0x80 >> (nStartBit % 8))) != 0) {
                break;
            }
            nZeroNum++;
            nStartBit++;
        }
        nStartBit++;

        int dwRet = 0;
        for (int i = 0; i < nZeroNum; i++) {
            dwRet <<= 1;
            if ((pBuff[nStartBit / 8] & (0x80 >> (nStartBit % 8))) != 0) {
                dwRet += 1;
            }
            nStartBit++;
        }
        return (1 << nZeroNum) - 1 + dwRet;
    }

    private static int Se(byte[] pBuff, int nLen) {
        int UeVal = Ue(pBuff, nLen);
        double k = UeVal;
        int nValue = (int) Math.ceil(k / 2);
        if (UeVal % 2 == 0) {
            nValue = -nValue;
        }
        return nValue;
    }

    private static int u(int BitCount, byte[] buf) {
        int dwRet = 0;
        for (int i = 0; i < BitCount; i++) {
            dwRet <<= 1;
            if ((buf[nStartBit / 8] & (0x80 >> (nStartBit % 8))) != 0) {
                dwRet += 1;
            }
            nStartBit++;
        }
        return dwRet;
    }

    private static boolean h264_decode_seq_parameter_set(byte[] buf, int nLen, int[] size) {
        nStartBit = 0;
        int forbidden_zero_bit = u(1, buf);
        int nal_ref_idc = u(2, buf);
        int nal_unit_type = u(5, buf);
        if (nal_unit_type == 7) {
            int profile_idc = u(8, buf);
            int constraint_set0_flag = u(1, buf);//(buf[1] & 0x80)>>7;
            int constraint_set1_flag = u(1, buf);//(buf[1] & 0x40)>>6;
            int constraint_set2_flag = u(1, buf);//(buf[1] & 0x20)>>5;
            int constraint_set3_flag = u(1, buf);//(buf[1] & 0x10)>>4;
            int reserved_zero_4bits = u(4, buf);
            int level_idc = u(8, buf);

            int seq_parameter_set_id = Ue(buf, nLen);

            if (profile_idc == 100 || profile_idc == 110 ||
                    profile_idc == 122 || profile_idc == 144) {
                int chroma_format_idc = Ue(buf, nLen);
                if (chroma_format_idc == 3) {
                    int residual_colour_transform_flag = u(1, buf);
                }
                int bit_depth_luma_minus8 = Ue(buf, nLen);
                int bit_depth_chroma_minus8 = Ue(buf, nLen);
                int qpprime_y_zero_transform_bypass_flag = u(1, buf);
                int seq_scaling_matrix_present_flag = u(1, buf);

                int[] seq_scaling_list_present_flag = new int[8];
                if (seq_scaling_matrix_present_flag != 0) {
                    for (int i = 0; i < 8; i++) {
                        seq_scaling_list_present_flag[i] = u(1, buf);
                    }
                }
            }
            int log2_max_frame_num_minus4 = Ue(buf, nLen);
            int pic_order_cnt_type = Ue(buf, nLen);
            if (pic_order_cnt_type == 0) {
                int log2_max_pic_order_cnt_lsb_minus4 = Ue(buf, nLen);
            } else if (pic_order_cnt_type == 1) {
                int delta_pic_order_always_zero_flag = u(1, buf);
                int offset_for_non_ref_pic = Se(buf, nLen);
                int offset_for_top_to_bottom_field = Se(buf, nLen);
                int num_ref_frames_in_pic_order_cnt_cycle = Ue(buf, nLen);

                int[] offset_for_ref_frame = new int[num_ref_frames_in_pic_order_cnt_cycle];
                for (int i = 0; i < num_ref_frames_in_pic_order_cnt_cycle; i++) {
                    offset_for_ref_frame[i] = Se(buf, nLen);
                }
            }
            int num_ref_frames = Ue(buf, nLen);
            int gaps_in_frame_num_value_allowed_flag = u(1, buf);
            int pic_width_in_mbs_minus1 = Ue(buf, nLen);
            int pic_height_in_map_units_minus1 = Ue(buf, nLen);

            size[0] = (pic_width_in_mbs_minus1 + 1) * 16;
            size[1] = (pic_height_in_map_units_minus1 + 1) * 16;

/*
        int frame_mbs_only_flag=u(1,buf,StartBit);
        if(!frame_mbs_only_flag)
            int mb_adaptive_frame_field_flag=u(1,buf,StartBit);

        int direct_8x8_inference_flag=u(1,buf,StartBit);
        int frame_cropping_flag=u(1,buf,StartBit);
        if(frame_cropping_flag)
        {
            int frame_crop_left_offset=Ue(buf,nLen,StartBit);
            int frame_crop_right_offset=Ue(buf,nLen,StartBit);
            int frame_crop_top_offset=Ue(buf,nLen,StartBit);
            int frame_crop_bottom_offset=Ue(buf,nLen,StartBit);
        }
        int vui_parameter_present_flag=u(1,buf,StartBit);
        if(vui_parameter_present_flag)
        {
            int aspect_ratio_info_present_flag=u(1,buf,StartBit);
            if(aspect_ratio_info_present_flag)
            {
                int aspect_ratio_idc=u(8,buf,StartBit);
                if(aspect_ratio_idc==255)
                {
                    int sar_width=u(16,buf,StartBit);
                    int sar_height=u(16,buf,StartBit);
                }
            }
            int overscan_info_present_flag=u(1,buf,StartBit);
            if(overscan_info_present_flag)
                int overscan_appropriate_flagu=u(1,buf,StartBit);
            int video_signal_type_present_flag=u(1,buf,StartBit);
            if(video_signal_type_present_flag)
            {
                int video_format=u(3,buf,StartBit);
                int video_full_range_flag=u(1,buf,StartBit);
                int colour_description_present_flag=u(1,buf,StartBit);
                if(colour_description_present_flag)
                {
                    int colour_primaries=u(8,buf,StartBit);
                    int transfer_characteristics=u(8,buf,StartBit);
                    int matrix_coefficients=u(8,buf,StartBit);
                }
            }
            int chroma_loc_info_present_flag=u(1,buf,StartBit);
            if(chroma_loc_info_present_flag)
            {
                int chroma_sample_loc_type_top_field=Ue(buf,nLen,StartBit);
                int chroma_sample_loc_type_bottom_field=Ue(buf,nLen,StartBit);
            }
            int timing_info_present_flag=u(1,buf,StartBit);

            if(timing_info_present_flag)
            {
                int num_units_in_tick=u(32,buf,StartBit);
                int time_scale=u(32,buf,StartBit);
                fps=time_scale/num_units_in_tick;
                int fixed_frame_rate_flag=u(1,buf,StartBit);
                if(fixed_frame_rate_flag)
                {
                    fps=fps/2;
                }
            }
        }
*/
            return true;
        }
        return false;
    }

    public static int[] getSizeFromSps(byte[] data) {
//        for (int i=0; i<data.length-4; i++)
//        {
            if (data[i]==0 && data[i+1]==0 && data[i+2]==0 && data[i+3]==1 && data[i+4]==0x67)
            {
                int[] size = new int[2];
                h264_decode_seq_parameter_set(data, data.length, size);
                Log.d(TAG, "Sps=("+size[0]+", "+size[1]+")");
                return size;
            }
//        }
        int[] size = new int[2];
        h264_decode_seq_parameter_set(data, data.length, size);
        Log.e(TAG, "Sps=(" + size[0] + ", " + size[1] + ")");
        return size;
    }

}

 

标签:java,StartBit,H264,SPS,nLen,int,flag,Ue,buf
来源: https://blog.csdn.net/xiaopangcame/article/details/114239161