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-rw-r--r--test/test_tt.c205
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diff --git a/test/test_tt.c b/test/test_tt.c
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+/* test_tt.c - example of using PES filter for teletext output.
+ * c.f. ETSI EN-300-472
+ *
+ * usage: DEMUX=/dev/dvb/adapterX/demuxX test_tt PID
+ *
+ * Copyright (C) 2002 convergence GmbH
+ * Johannes Stezenbach <js@convergence.de> based on code by
+ * Ralph Metzler <ralph@convergence.de> and Marcus Metzler <marcus@convergence.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1
+ * 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
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser 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 <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+
+#include <linux/dvb/dmx.h>
+
+#include "hex_dump.h"
+
+#define MAX_PES_SIZE (4*1024)
+
+
+uint8_t reverse[] = {
+0x00,0x80,0x40,0xC0,0x20,0xA0,0x60,0xE0,0x10,0x90,0x50,0xD0,0x30,0xB0,0x70,0xF0,
+0x08,0x88,0x48,0xC8,0x28,0xA8,0x68,0xE8,0x18,0x98,0x58,0xD8,0x38,0xB8,0x78,0xF8,
+0x04,0x84,0x44,0xC4,0x24,0xA4,0x64,0xE4,0x14,0x94,0x54,0xD4,0x34,0xB4,0x74,0xF4,
+0x0C,0x8C,0x4C,0xCC,0x2C,0xAC,0x6C,0xEC,0x1C,0x9C,0x5C,0xDC,0x3C,0xBC,0x7C,0xFC,
+0x02,0x82,0x42,0xC2,0x22,0xA2,0x62,0xE2,0x12,0x92,0x52,0xD2,0x32,0xB2,0x72,0xF2,
+0x0A,0x8A,0x4A,0xCA,0x2A,0xAA,0x6A,0xEA,0x1A,0x9A,0x5A,0xDA,0x3A,0xBA,0x7A,0xFA,
+0x06,0x86,0x46,0xC6,0x26,0xA6,0x66,0xE6,0x16,0x96,0x56,0xD6,0x36,0xB6,0x76,0xF6,
+0x0E,0x8E,0x4E,0xCE,0x2E,0xAE,0x6E,0xEE,0x1E,0x9E,0x5E,0xDE,0x3E,0xBE,0x7E,0xFE,
+0x01,0x81,0x41,0xC1,0x21,0xA1,0x61,0xE1,0x11,0x91,0x51,0xD1,0x31,0xB1,0x71,0xF1,
+0x09,0x89,0x49,0xC9,0x29,0xA9,0x69,0xE9,0x19,0x99,0x59,0xD9,0x39,0xB9,0x79,0xF9,
+0x05,0x85,0x45,0xC5,0x25,0xA5,0x65,0xE5,0x15,0x95,0x55,0xD5,0x35,0xB5,0x75,0xF5,
+0x0D,0x8D,0x4D,0xCD,0x2D,0xAD,0x6D,0xED,0x1D,0x9D,0x5D,0xDD,0x3D,0xBD,0x7D,0xFD,
+0x03,0x83,0x43,0xC3,0x23,0xA3,0x63,0xE3,0x13,0x93,0x53,0xD3,0x33,0xB3,0x73,0xF3,
+0x0B,0x8B,0x4B,0xCB,0x2B,0xAB,0x6B,0xEB,0x1B,0x9B,0x5B,0xDB,0x3B,0xBB,0x7B,0xFB,
+0x07,0x87,0x47,0xC7,0x27,0xA7,0x67,0xE7,0x17,0x97,0x57,0xD7,0x37,0xB7,0x77,0xF7,
+0x0F,0x8F,0x4F,0xCF,0x2F,0xAF,0x6F,0xEF,0x1F,0x9F,0x5F,0xDF,0x3F,0xBF,0x7F,0xFF
+};
+
+
+
+void usage(void)
+{
+ fprintf(stderr, "usage: test_tt PID\n");
+ fprintf(stderr, " The default demux device used can be changed\n");
+ fprintf(stderr, " using the DEMUX environment variable\n");
+ exit(1);
+}
+
+void safe_read(int fd, void *buf, int count)
+{
+ int bytes;
+
+ do {
+ bytes = read(fd, buf, count);
+ if (bytes < 0) {
+ if (errno == EOVERFLOW)
+ fprintf(stderr, "read error: buffer overflow (%d)\n",
+ EOVERFLOW);
+ else {
+ perror("read");
+ exit(1);
+ }
+ }
+ else if (bytes == 0) {
+ fprintf(stderr, "got EOF on demux!?\n");
+ exit(1);
+ }
+ } while (bytes < count);
+}
+
+void process_pes(int fd)
+{
+ uint8_t buf[MAX_PES_SIZE];
+ int i, plen, hlen, sid, lines, l;
+
+ /* search for start of next PES data block 0x000001bd */
+ for (;;) {
+ safe_read(fd, buf, 1);
+ if (buf[0] != 0) continue;
+ safe_read(fd, buf, 1);
+ if (buf[0] != 0) continue;
+ safe_read(fd, buf, 1);
+ if (buf[0] != 1) continue;
+ safe_read(fd, buf, 1);
+ if (buf[0] == 0xbd)
+ break;
+ }
+
+ safe_read(fd, buf, 5);
+ /* PES packet length */
+ plen = ((buf[0] << 8) | buf[1]) & 0xffff;
+
+ /* PES header data length */
+ hlen = buf[4];
+ if (hlen != 0x24) {
+ fprintf(stderr, "error: PES header data length != 0x24 (0x%02x)\n", hlen);
+ return;
+ }
+ /* skip rest of PES header */
+ safe_read(fd, buf, hlen);
+
+ /* read stream ID */
+ safe_read(fd, buf, 1);
+ sid = buf[0];
+ if (sid < 0x10 || sid > 0x1f) {
+ fprintf(stderr, "error: non-EBU stream ID 0x%02x\n", sid);
+ return;
+ }
+
+ /* number of VBI lines */
+ lines = (plen + 6) / 46 - 1;
+
+ /* read VBI data */
+ for (l = 0; l < lines; l++) {
+ safe_read(fd, buf, 46);
+ if (buf[1] != 44) {
+ fprintf(stderr, "error: VBI line has invalid length\n");
+ return;
+ }
+ /* bit twiddling */
+ for (i = 2; i < 46; i++)
+ buf[i] = reverse[buf[i]];
+ /* framing code, should be 11100100b */
+ if (buf[3] != 0x27) {
+ fprintf(stderr, "error: wrong framing code\n");
+ return;
+ }
+ /* remaining data needs to be hamming decoded, but we should
+ * be able to read some partial strings */
+ hex_dump(buf, 46);
+ printf("\n");
+ }
+}
+
+int set_filter(int fd, unsigned int pid)
+{
+ struct dmx_pes_filter_params f;
+
+ f.pid = (uint16_t) pid;
+ f.input = DMX_IN_FRONTEND;
+ f.output = DMX_OUT_TAP;
+ f.pes_type = DMX_PES_OTHER; /* DMX_PES_TELETEXT if you want vbi insertion */
+ f.flags = DMX_IMMEDIATE_START;
+ if (ioctl(fd, DMX_SET_PES_FILTER, &f) == -1) {
+ perror("ioctl DMX_SET_PES_FILTER");
+ return 1;
+ }
+ return 0;
+}
+
+
+int main(int argc, char *argv[])
+{
+ int dmxfd;
+ unsigned long pid;
+ char * dmxdev = "/dev/dvb/adapter0/demux0";
+
+ if (argc != 2)
+ usage();
+
+ pid = strtoul(argv[1], NULL, 0);
+ if (pid > 0x1fff)
+ usage();
+ if (getenv("DEMUX"))
+ dmxdev = getenv("DEMUX");
+ fprintf(stderr, "test_tt: using '%s'\n", dmxdev);
+ fprintf(stderr, " PID 0x%04lx\n", pid);
+
+ if ((dmxfd = open(dmxdev, O_RDWR)) < 0){
+ perror("open");
+ return 1;
+ }
+
+ if (set_filter(dmxfd, pid) != 0)
+ return 1;
+
+ for (;;) {
+ process_pes(dmxfd);
+ }
+
+ close(dmxfd);
+ return 0;
+}
+