mpg_common.c

Go to the documentation of this file.

/*
 * mpg_common.c: COMMON MPEG functions for replex
 *        
 *
 * Copyright (C) 2003 Marcus Metzler <mocm@metzlerbros.de>
 *                    Metzler Brothers Systementwicklung GbR
 * Changes to use MythTV logging
 * Copyright (C) 2011 Gavin Hurlbut <ghurlbut@mythtv.org>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * General Public License for more details.
 *
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 * Or, point your browser to http://www.gnu.org/copyleft/gpl.html
 *
 */

#include <stdio.h>
#include <string.h>
#include "element.h"
#include "pes.h"
#include "ts.h"

#include "mythlogging.h"

void show_buf(uint8_t *buf, int length)
{
        int i,j,r;
        uint8_t buffer[100];
        uint8_t temp[8];
        buffer[0] = '\0';

        for (i=0; i<length; i+=16){
                for (j=0; j < 8 && j+i<length; j++)
                {
                        sprintf(temp,"0x%02x ", (int)(buf[i+j]));
                        strcat(buffer, temp);
                }
                for (r=j; r<8; r++)                     
                        strcat(buffer, "     ");

                strcat(buffer, "  ");

                for (j=8; j < 16 && j+i<length; j++)
                {
                        sprintf(temp, "0x%02x ", (int)(buf[i+j]));
                        strcat(buffer, temp);
                }
                for (r=j; r<16; r++)                    
                        strcat(buffer, "     ");

                for (j=0; j < 16 && j+i<length; j++){
                        switch(buf[i+j]){
                        case '0'...'Z':
                        case 'a'...'z':
                                sprintf(temp, "%c", buf[i+j]);
                                break;
                        default:
                                sprintf(temp, ".");
                        }
                        strcat(buffer, temp);
                }
                LOG(VB_GENERAL, LOG_INFO, buffer);
        }
}



int find_mpg_header(uint8_t head, uint8_t *buf, int length)
{

        int c = 0;
        int found=0;

        if (length <0) return -1;

        while (found < 4 && c < length){
                switch(found){

                case 0:
                        if (buf[c] == 0x00) found = 1;
                        break;

                case 1:
                        if (buf[c] == 0x00) found = 2;
                        else found = 0;
                        break;
                        
                case 2:
                        if (buf[c] == 0x01) found = 3;
                        else if (buf[c] != 0x00) found = 0;
                        break;

                case 3:
                        if (buf[c] == head) return c-3;
                        else found = 0;
                        break;
                }
                c++;
        }
        return -1;
}


int find_any_header(uint8_t *head, uint8_t *buf, int length)
{

        int c = 0;
        int found=0;

        if (length <0) return -1;

        while (found < 4 && c < length){
                switch(found){

                case 0:
                        if (buf[c] == 0x00) found = 1;
                        break;

                case 1:
                        if (buf[c] == 0x00) found = 2;
                        else found = 0;
                        break;
                        
                case 2:
                        if (buf[c] == 0x01) found = 3;
                        else if (buf[c] != 0x00) found = 0;
                        break;

                case 3:
                        *head = buf[c];
                        return c-3;
                        break;
                }
                c++;
        }
        return -1;
}


uint64_t trans_pts_dts(uint8_t *pts)
{
        uint64_t wts;
        
        wts = ((uint64_t)((pts[0] & 0x0E) << 5) | 
               ((pts[1] & 0xFC) >> 2)) << 24; 
        wts |= (((pts[1] & 0x03) << 6) |
                ((pts[2] & 0xFC) >> 2)) << 16; 
        wts |= (((pts[2] & 0x02) << 6) |
                ((pts[3] & 0xFE) >> 1)) << 8;
        wts |= (((pts[3] & 0x01) << 7) |
                ((pts[4] & 0xFE) >> 1));

        wts = wts*300ULL;
        return wts;
}


int mring_peek( ringbuffer *rbuf, uint8_t *buf, unsigned int l, uint32_t off)
{
        int c = 0;

        if (ring_avail(rbuf)+off <= l)
                return -1;

        c = ring_peek(rbuf, buf, l, off);
        return c+off;
}



int ring_find_mpg_header(ringbuffer *rbuf, uint8_t head, int off, int le)
{

        int c = 0;
        int found = 0;

        c = off;
        while ( c-off < le){
                uint8_t b;
                if ( mring_peek(rbuf, &b, 1, c) <0) return -1;
                switch(found){

                case 0:
                        if (b == 0x00) found = 1;
                        break;

                case 1:
                        if (b == 0x00) found = 2;
                        else found = 0;
                        break;
                        
                case 2:
                        if (b == 0x01) found = 3;
                        else if (b != 0x00) found = 0;
                        break;

                case 3:
                        if (b == head) return c-3-off;
                        else found = 0;
                        break;
                }
                c++;
                
        }
        if (found) return -2;
        else return -1;
}


int ring_find_any_header(ringbuffer *rbuf, uint8_t *head, int off, int le)
{

        int c = 0;
        int found =0;

        c = off;
        while ( c-off < le){
                uint8_t b;
                if ( mring_peek(rbuf, &b, 1, c) <0){
                        return -1;
                }
                switch(found){

                case 0:
                        if (b == 0x00) found = 1;
                        break;

                case 1:
                        if (b == 0x00) found = 2;
                        else found = 0;
                        break;
                        
                case 2:
                        if (b == 0x01) found = 3;
                        else if (b != 0x00) found = 0;
                        break;

                case 3:
                        *head = b;
                        return c-3-off;
                        break;
                }
                c++;
        }
        if (found) return -2;
        else return -1;
}

---