+++ /dev/null
-/*
- * extract_a52.c
- * Copyright (C) 2000-2002 Michel Lespinasse <walken@zoy.org>
- * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
- *
- * This file is part of a52dec, a free ATSC A-52 stream decoder.
- * See http://liba52.sourceforge.net/ for updates.
- *
- * a52dec 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.
- *
- * a52dec 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
- * GNU 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
- */
-
-#include "config.h"
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <getopt.h>
-#include <inttypes.h>
-
-#define BUFFER_SIZE 4096
-static uint8_t buffer[BUFFER_SIZE];
-static FILE * in_file;
-static int demux_track = 0x80;
-static int demux_pid = 0;
-
-static void print_usage (char ** argv)
-{
- fprintf (stderr, "usage: %s [-s <track>] [-t <pid>] <file>\n"
- "\t-s\tset track number (0-7 or 0x80-0x87)\n"
- "\t-t\tuse transport stream demultiplexer, pid 0x10-0x1ffe\n",
- argv[0]);
-
- exit (1);
-}
-
-static void handle_args (int argc, char ** argv)
-{
- int c;
- char * s;
-
- while ((c = getopt (argc, argv, "s:t:")) != -1)
- switch (c) {
- case 's':
- demux_track = strtol (optarg, &s, 16);
- if (demux_track < 0x80)
- demux_track += 0x80;
- if ((demux_track < 0x80) || (demux_track > 0x87) || (*s)) {
- fprintf (stderr, "Invalid track number: %s\n", optarg);
- print_usage (argv);
- }
- break;
-
- case 't':
- demux_pid = strtol (optarg, &s, 16);
- if ((demux_pid < 0x10) || (demux_pid > 0x1ffe) || (*s)) {
- fprintf (stderr, "Invalid pid: %s\n", optarg);
- print_usage (argv);
- }
- break;
-
- default:
- print_usage (argv);
- }
-
- if (optind < argc) {
- in_file = fopen (argv[optind], "rb");
- if (!in_file) {
- fprintf (stderr, "%s - couldnt open file %s\n", strerror (errno),
- argv[optind]);
- exit (1);
- }
- } else
- in_file = stdin;
-}
-
-#define DEMUX_PAYLOAD_START 1
-static int demux (uint8_t * buf, uint8_t * end, int flags)
-{
- static int mpeg1_skip_table[16] = {
- 0, 0, 4, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
- };
-
- /*
- * the demuxer keeps some state between calls:
- * if "state" = DEMUX_HEADER, then "head_buf" contains the first
- * "bytes" bytes from some header.
- * if "state" == DEMUX_DATA, then we need to copy "bytes" bytes
- * of ES data before the next header.
- * if "state" == DEMUX_SKIP, then we need to skip "bytes" bytes
- * of data before the next header.
- *
- * NEEDBYTES makes sure we have the requested number of bytes for a
- * header. If we dont, it copies what we have into head_buf and returns,
- * so that when we come back with more data we finish decoding this header.
- *
- * DONEBYTES updates "buf" to point after the header we just parsed.
- */
-
-#define DEMUX_HEADER 0
-#define DEMUX_DATA 1
-#define DEMUX_SKIP 2
- static int state = DEMUX_SKIP;
- static int state_bytes = 0;
- static uint8_t head_buf[268];
-
- uint8_t * header;
- int bytes;
- int len;
-
-#define NEEDBYTES(x) \
- do { \
- int missing; \
- \
- missing = (x) - bytes; \
- if (missing > 0) { \
- if (header == head_buf) { \
- if (missing <= end - buf) { \
- memcpy (header + bytes, buf, missing); \
- buf += missing; \
- bytes = (x); \
- } else { \
- memcpy (header + bytes, buf, end - buf); \
- state_bytes = bytes + end - buf; \
- return 0; \
- } \
- } else { \
- memcpy (head_buf, header, bytes); \
- state = DEMUX_HEADER; \
- state_bytes = bytes; \
- return 0; \
- } \
- } \
- } while (0)
-
-#define DONEBYTES(x) \
- do { \
- if (header != head_buf) \
- buf = header + (x); \
- } while (0)
-
- if (flags & DEMUX_PAYLOAD_START)
- goto payload_start;
- switch (state) {
- case DEMUX_HEADER:
- if (state_bytes > 0) {
- header = head_buf;
- bytes = state_bytes;
- goto continue_header;
- }
- break;
- case DEMUX_DATA:
- if (demux_pid || (state_bytes > end - buf)) {
- fwrite (buf, end - buf, 1, stdout);
- state_bytes -= end - buf;
- return 0;
- }
- fwrite (buf, state_bytes, 1, stdout);
- buf += state_bytes;
- break;
- case DEMUX_SKIP:
- if (demux_pid || (state_bytes > end - buf)) {
- state_bytes -= end - buf;
- return 0;
- }
- buf += state_bytes;
- break;
- }
-
- while (1) {
- if (demux_pid) {
- state = DEMUX_SKIP;
- return 0;
- }
- payload_start:
- header = buf;
- bytes = end - buf;
- continue_header:
- NEEDBYTES (4);
- if (header[0] || header[1] || (header[2] != 1)) {
- if (demux_pid) {
- state = DEMUX_SKIP;
- return 0;
- } else if (header != head_buf) {
- buf++;
- goto payload_start;
- } else {
- header[0] = header[1];
- header[1] = header[2];
- header[2] = header[3];
- bytes = 3;
- goto continue_header;
- }
- }
- if (demux_pid && (header[3] != 0xbd)) {
- fprintf (stderr, "bad stream id %x\n", header[3]);
- exit (1);
- }
- switch (header[3]) {
- case 0xb9: /* program end code */
- /* DONEBYTES (4); */
- /* break; */
- return 1;
- case 0xba: /* pack header */
- NEEDBYTES (12);
- if ((header[4] & 0xc0) == 0x40) { /* mpeg2 */
- NEEDBYTES (14);
- len = 14 + (header[13] & 7);
- NEEDBYTES (len);
- DONEBYTES (len);
- /* header points to the mpeg2 pack header */
- } else if ((header[4] & 0xf0) == 0x20) { /* mpeg1 */
- DONEBYTES (12);
- /* header points to the mpeg1 pack header */
- } else {
- fprintf (stderr, "weird pack header\n");
- exit (1);
- }
- break;
- case 0xbd: /* private stream 1 */
- NEEDBYTES (7);
- if ((header[6] & 0xc0) == 0x80) { /* mpeg2 */
- NEEDBYTES (9);
- len = 10 + header[8];
- NEEDBYTES (len);
- /* header points to the mpeg2 pes header */
- } else { /* mpeg1 */
- len = 7;
- while ((header-1)[len] == 0xff) {
- len++;
- NEEDBYTES (len);
- if (len == 23) {
- fprintf (stderr, "too much stuffing\n");
- break;
- }
- }
- if (((header-1)[len] & 0xc0) == 0x40) {
- len += 2;
- NEEDBYTES (len);
- }
- len += mpeg1_skip_table[(header - 1)[len] >> 4] + 1;
- NEEDBYTES (len);
- /* header points to the mpeg1 pes header */
- }
- if ((!demux_pid) && ((header-1)[len] != demux_track)) {
- DONEBYTES (len);
- bytes = 6 + (header[4] << 8) + header[5] - len;
- if (bytes <= 0)
- continue;
- goto skip;
- }
- len += 3;
- NEEDBYTES (len);
- DONEBYTES (len);
- bytes = 6 + (header[4] << 8) + header[5] - len;
- if (demux_pid || (bytes > end - buf)) {
- fwrite (buf, end - buf, 1, stdout);
- state = DEMUX_DATA;
- state_bytes = bytes - (end - buf);
- return 0;
- } else if (bytes <= 0)
- continue;
- fwrite (buf, bytes, 1, stdout);
- buf += bytes;
- break;
- default:
- if (header[3] < 0xb9) {
- fprintf (stderr,
- "looks like a video stream, not system stream\n");
- exit (1);
- } else {
- NEEDBYTES (6);
- DONEBYTES (6);
- bytes = (header[4] << 8) + header[5];
- skip:
- if (bytes > end - buf) {
- state = DEMUX_SKIP;
- state_bytes = bytes - (end - buf);
- return 0;
- }
- buf += bytes;
- }
- }
- }
-}
-
-static void ps_loop (void)
-{
- uint8_t * end;
-
- do {
- end = buffer + fread (buffer, 1, BUFFER_SIZE, in_file);
- if (demux (buffer, end, 0))
- break; /* hit program_end_code */
- } while (end == buffer + BUFFER_SIZE);
-}
-
-static void ts_loop (void)
-{
-#define PACKETS (BUFFER_SIZE / 188)
- uint8_t * buf;
- uint8_t * data;
- uint8_t * end;
- int packets;
- int i;
- int pid;
-
- do {
- packets = fread (buffer, 188, PACKETS, in_file);
- for (i = 0; i < packets; i++) {
- buf = buffer + i * 188;
- end = buf + 188;
- if (buf[0] != 0x47) {
- fprintf (stderr, "bad sync byte\n");
- exit (1);
- }
- pid = ((buf[1] << 8) + buf[2]) & 0x1fff;
- if (pid != demux_pid)
- continue;
- data = buf + 4;
- if (buf[3] & 0x20) { /* buf contains an adaptation field */
- data = buf + 5 + buf[4];
- if (data > end)
- continue;
- }
- if (buf[3] & 0x10)
- demux (data, end, (buf[1] & 0x40) ? DEMUX_PAYLOAD_START : 0);
- }
- } while (packets == PACKETS);
-}
-
-int main (int argc, char ** argv)
-{
- handle_args (argc, argv);
-
- if (demux_pid)
- ts_loop ();
- else
- ps_loop ();
-
- return 0;
-}
projects / goodguy / history.git / blobdiff