F5OEO-tstools/ps.c

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/*
* Utilities for reading program stream data.
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the MPEG TS, PS and ES tools.
*
* The Initial Developer of the Original Code is Amino Communications Ltd.
* Portions created by the Initial Developer are Copyright (C) 2008
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Amino Communications Ltd, Swavesey, Cambridge UK
*
* ***** END LICENSE BLOCK *****
*/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#ifdef _WIN32
#include <stddef.h>
#include <io.h>
#else // _WIN32
#include <unistd.h>
#endif // _WIN32
#include "compat.h"
#include "ps_fns.h"
#include "ts_fns.h"
#include "pes_fns.h"
#include "pidint_fns.h"
#include "misc_fns.h"
#define DEBUG 0
#define DEBUG_AC3 0
// How many bytes to look through for a pack header, before giving up
#define PACK_HEADER_SEARCH_DISTANCE 100000
// If we lose where we are, should we look for the next PS pack header?
// (instead of just giving up)
#define RECOVER_BROKEN_PS 1
// ============================================================
// PS to TS datastructures
// ============================================================
// Data we need to write PAT/PMT and otherwise manage our program streams
//
// DVD allows one video stream and up to 8 audio streams,
// but we're only interested in a single video and a single audio stream
struct program_data
{
// Information supplied by the user
u_int32 transport_stream_id;
u_int32 program_number;
u_int32 pmt_pid; // PID to use for the PMT
u_int32 pcr_pid; // PID to use for the PCR
u_int32 video_pid; // PID to use for our single stream of video
u_int32 audio_pid; // PID to use for our single stream of audio
int video_stream; // Which stream id our video is (-1 means use first)
int audio_stream; // Which stream id our audio is (-1 means use first)
int want_ac3; // True means audio_stream is private_1/AC3 substream
int audio_substream; // Which substream id if DVD and want_ac3
int video_type; // Is our video H.264, H.262, etc. (user must decide)
int is_dvd; // Is our data DVD program stream (ditto)
int output_dolby_as_dvb; // Output Dolby (AC-3) audio as DVB or ATSC?
// Information derived from the data
// PAT and PMT data
pidint_list_p prog_list;
pmt_p pmt;
};
// ============================================================
// Read ahead support
// ============================================================
/*
* Read some more data into our read-ahead buffer.
*
* Returns 0 if it succeeds, EOF if the end-of-file is read, otherwise
* 1 if some error occurs.
*/
static inline int get_more_data(PS_reader_p ps)
{
// Call `read` directly - we don't particularly mind if we get a "short"
// read, since we'll just catch up later on
#ifdef _WIN32
int len = _read(ps->input,&ps->data,PS_READ_AHEAD_SIZE);
#else
ssize_t len = read(ps->input,&ps->data,PS_READ_AHEAD_SIZE);
#endif
if (len == 0)
return EOF;
else if (len == -1)
{
fprintf(stderr,"### Error reading next bytes: %s\n",strerror(errno));
return 1;
}
ps->data_posn += ps->data_len; // length of the *last* buffer
ps->data_len = len;
ps->data_end = ps->data + len; // one beyond the last byte
ps->data_ptr = ps->data; // start at the beginning
return 0;
}
/*
* Build a program stream context attached to an input file. This handles
* read-ahead buffering for the PS.
*
* - `input` is the file stream to read from.
* - If `quiet`, then don't report on ignored bytes at the start of the file
* - `ps` is the new PS context
*
* Returns 0 if all goes well, 1 otherwise.
*/
extern int build_PS_reader(int input,
int quiet,
PS_reader_p *ps)
{
int err;
PS_reader_p new = malloc(SIZEOF_PS_READER);
if (new == NULL)
{
fprintf(stderr,"### Unable to allocate program stream read context\n");
return 1;
}
new->input = input;
new->data_posn = 0;
new->data_len = 0;
new->start = 0;
err = get_more_data(new);
if (err)
{
fprintf(stderr,"### Unable to start reading from new PS read context\n");
free(new);
return 1;
}
// And look for the first pack header
err = find_PS_pack_header_start(new,FALSE,PACK_HEADER_SEARCH_DISTANCE,
&(new->start));
if (err)
{
fprintf(stderr,"### File does not appear to be PS\n"
" Cannot find PS pack header in first %d bytes of file\n",
PACK_HEADER_SEARCH_DISTANCE);
free(new);
return 1;
}
// But we don't *really* want to have read its start yet
err = seek_using_PS_reader(new,new->start);
if (err)
{
fprintf(stderr,"### Error seeking to start of first pack header\n");
free(new);
return 1;
}
if (!quiet && new->start != 0)
fprintf(stderr,
"!!! PS file does not start with pack header\n"
" First PS pack header is at " OFFSET_T_FORMAT "\n",new->start);
*ps = new;
return 0;
}
/*
* Tidy up the PS read-ahead context after we've finished with it.
*
* Specifically:
*
* - free the datastructure
* - set `ps` to NULL
*
* Does not close the associated file.
*/
extern void free_PS_reader(PS_reader_p *ps)
{
if (*ps != NULL)
{
(*ps)->input = -1; // "forget" our input
free(*ps);
*ps = NULL;
}
}
/*
* Open a PS file for reading.
*
* - `name` is the name of the file. If this is NULL, then standard input
* is used.
* - If `quiet`, then don't report on ignored bytes at the start of the file
* - `ps` is the new PS context
*
* Returns 0 if all goes well, 1 otherwise.
*/
extern int open_PS_file(char *name,
int quiet,
PS_reader_p *ps)
{
int f;
if (name == NULL)
f = STDIN_FILENO;
else
{
f = open_binary_file(name,FALSE);
if (f == -1) return 1;
}
return build_PS_reader(f,quiet,ps);
}
/*
* Close a PS file, and free the reader context
*
* (Doesn't close the file if it was standard input)
*
* Returns 0 if all goes well, 1 otherwise.
*/
extern int close_PS_file(PS_reader_p *ps)
{
if ((*ps)->input != STDIN_FILENO)
{
int err = close_file((*ps)->input);
if (err) return 1;
}
free_PS_reader(ps);
return 0;
}
/*
* Given a program stream, attempt to determine if it holds H.262 or H.264
* data.
*
* Leaves the PS rewound to its "start".
*
* NOTE: It is probably better to use determine_PS_video_type().
*
* - `ps` is the program stream to check (assumed just to have been
* opened/built). This cannot be standard input, as it must be
* seekable.
* - `is_h264` is the result
*
* Returns 0 if all goes well, 1 if there was an error (including the
* stream not appearing to be either).
*/
extern int determine_if_PS_is_h264(PS_reader_p ps,
int *is_h264)
{
int err;
PES_reader_p reader;
// Try to decide what sort of data stream we have
// The simplest (albeit clumsy) way to do this is to use technology
// that already does this for us - i.e., build a temporary PES reader
// around our file
// It's then safe to build the temporary PES reader
err = build_PS_PES_reader(ps,FALSE,FALSE,&reader);
if (err)
{
fprintf(stderr,"### Error trying to determine PS stream type\n");
return 1;
}
// Which knows the file type
*is_h264 = reader->is_h264;
(void) free_PES_reader(&reader);
// And then make sure that our file position is where we think it should be
err = rewind_program_stream(ps);
if (err)
{
fprintf(stderr,"### Error rewinding PS file after determining its type\n");
return 1;
}
return 0;
}
/*
* Given a program stream, attempt to determine what type of video data it
* contains.
*
* Leaves the PS rewound to its "start".
*
* - `ps` is the program stream to check (assumed just to have been
* opened/built). This cannot be standard input, as it must be
* seekable.
* - `video_type` is the result. Calls determine_PES_video_type().
*
* Returns 0 if all goes well, 1 if there was an error (including the
* stream not appearing to be either).
*/
extern int determine_PS_video_type(PS_reader_p ps,
int *video_type)
{
int err;
PES_reader_p reader;
// Try to decide what sort of data stream we have
// The simplest (albeit clumsy) way to do this is to use technology
// that already does this for us - i.e., build a temporary PES reader
// around our file
// It's then safe to build the temporary PES reader
err = build_PS_PES_reader(ps,FALSE,FALSE,&reader);
if (err)
{
fprintf(stderr,"### Error trying to determine PS stream type\n");
return 1;
}
// Which thinks it knows the file type
*video_type = reader->video_type;
(void) free_PES_reader(&reader);
// And then make sure that our file position is where we think it should be
err = rewind_program_stream(ps);
if (err)
{
fprintf(stderr,"### Error rewinding PS file after determining its type\n");
return 1;
}
return 0;
}
/*
* Seek within the PS file.
*
* Note that if the intent is to *rewind* to the start of the PS data,
* then `rewind_program_stream` should be used instead, as offset 0 is
* not necessarily the same as the start of the program stream.
*
* - `ps` is the PS read-ahead context
* - `posn` is the file offset to seek to
*
* Return 0 if all goes well, 1 if something goes wrong
*/
extern int seek_using_PS_reader(PS_reader_p ps,
offset_t posn)
{
int err = seek_file(ps->input,posn);
if (err) return 1;
ps->data_posn = posn;
ps->data_len = 0;
return get_more_data(ps);
}
/*
* Rewind the PS context to the remembered "start of data"
*
* Returns 0 if all goes well, 1 if something goes wrong
*/
extern int rewind_program_stream(PS_reader_p ps)
{
return seek_using_PS_reader(ps,ps->start);
}
/*
* Retrieve the next N bytes from the program stream, into an existing array.
*
* - `ps` is the PS read-ahead context
* - `num_bytes` is how many bytes to read
* - `buffer` is the buffer to read them into
* - `posn` is the offset of said data in the file (NULL if the value is not
* wanted).
*
* Returns 0 if all goes well, EOF if end-of-file is encountered before all
* of the bytes have been read, 1 if some other error occurred.
*/
static int read_PS_bytes(PS_reader_p ps,
int num_bytes,
byte *buffer,
offset_t *posn)
{
int err;
int offset = 0;
int num_bytes_wanted = num_bytes;
int num_bytes_left = ps->data_end - ps->data_ptr;
if (posn != NULL)
*posn = ps->data_posn + (ps->data_ptr - ps->data);
for (;;)
{
if (num_bytes_left < num_bytes_wanted)
{
memcpy(&(buffer[offset]),ps->data_ptr,num_bytes_left);
offset += num_bytes_left;
num_bytes_wanted -= num_bytes_left;
err = get_more_data(ps);
if (err) return err;
num_bytes_left = ps->data_len;
}
else
{
memcpy(&(buffer[offset]),ps->data_ptr,num_bytes_wanted);
ps->data_ptr += num_bytes_wanted;
break;
}
}
return 0;
}
// ============================================================
// Primitives
// ============================================================
/*
* Print out a stream id in a manner consistent with the PS usages
* of the stream id values.
*/
extern void print_stream_id(FILE *stream,
byte stream_id)
{
byte number;
char *str = NULL;
switch (stream_id)
{
// H.222 Program stream specific codes
case 0xB9: str = "PS MPEG_program_end_code"; break;
case 0xBA: str = "PS Pack header start code"; break;
case 0xBB: str = "PS System header start code"; break;
case 0xBC: str = "PS Program stream map"; break;
case 0xFF: str = "PS Program stream directory"; break;
// Other "simple" values from H.222 Table 2-18, page 32
case 0xBD: str = "Private stream 1"; break;
case 0xBE: str = "Padding stream"; break;
case 0xBF: str = "Private stream 2"; break;
case 0xF0: str = "ECM stream"; break;
case 0xF1: str = "EMM stream"; break;
case 0xF2: str = "DSMCC stream"; break;
case 0xF3: str = "13522 stream"; break;
case 0xF4: str = "H.222.1 A stream"; break;
case 0xF5: str = "H.222.1 B stream"; break;
case 0xF6: str = "H.222.1 C stream"; break;
case 0xF7: str = "H.222.1 D stream"; break;
case 0xF8: str = "H.222.1 E stream"; break;
case 0xF9: str = "Ancillary stream"; break;
case 0x00: str = "H.262 Picture"; break;
case 0xB2: str = "H.262 User data"; break;
case 0xB3: str = "H.262 Sequence header"; break;
case 0xB4: str = "H.262 Sequence error"; break;
case 0xB5: str = "H.262 Extension"; break;
case 0xB7: str = "H.262 Sequence end"; break;
case 0xB8: str = "H.262 Group start"; break;
default: str = NULL; break;
}
if (str != NULL)
fprintf(stream,str);
else if (stream_id >= 0xC0 && stream_id <=0xDF)
{
number = stream_id & 0x1F;
fprintf(stream,"Audio stream 0x%02X",number);
}
else if (stream_id >= 0xE0 && stream_id <= 0xEF)
{
number = stream_id & 0x0F;
fprintf(stream,"Video stream 0x%X",number);
}
else if (stream_id >= 0xFC && stream_id <= 0xFE)
fprintf(stream,"Reserved data stream");
else
fprintf(stream,"Unrecognised stream id");
}
/*
* Look for the start (the first 4 bytes) of the next program stream packet.
*
* Assumes that (for some reason) alignment has been lost, and thus it is
* necessary to scan forwards to find the next 00 00 01 prefix.
*
* Otherwise equivalent to a call of `read_PS_packet_start`.
*
* - `ps` is the PS read-ahead context we're reading from
* - if `verbose`, then we want to explain what we're doing
* - if `max` is non-zero, then it is the maximum number of bytes
* to scan before giving up.
* - `posn` is the file offset of the start of the packet
* - `stream_id` is the identifying byte, after the 00 00 01 prefix. Note
* that this is set correctly if MPEG_program_end_code was read, and is
* 0 if an error occurred.
*
* Returns:
* * 0 if it succeeds,
* * EOF if EOF is read, or an MPEG_program_end_code is read, or
* * 1 if some error (including the first 3 bytes not being 00 00 01) occurs.
*/
extern int find_PS_packet_start(PS_reader_p ps,
int verbose,
u_int32 max,
offset_t *posn,
byte *stream_id)
{
int err;
byte prev1 = 0xff;
byte prev2 = 0xff;
byte prev3 = 0xff;
u_int32 count = 0;
*stream_id = 0;
for (;;)
{
byte *ptr;
for (ptr = ps->data_ptr; ptr < ps->data_end; ptr++)
{
if (prev3 == 0x00 && prev2 == 0x00 && prev1 == 0x01)
{
if (*ptr == 0xB9) // MPEG_program_end_code
{
if (verbose)
printf("Stopping at MPEG_program_end_code\n");
*stream_id = 0xB9;
return EOF;
}
else
{
*stream_id = *ptr;
*posn = ps->data_posn + (ptr - ps->data) - 3;
ps->data_ptr = ptr + 1;
return 0;
}
}
if (max > 0)
{
count ++;
if (count > max)
{
fprintf(stderr,"### No PS packet start found in %d bytes\n",max);
return 1;
}
}
prev3 = prev2;
prev2 = prev1;
prev1 = *ptr;
}
// We've run out of data - get some more
err = get_more_data(ps);
if (err) return err;
}
}
/*
* Look for the next PS pack header.
*
* Equivalent to calling `find_PS_packet_start` until `stream_id` is 0xBA
* (in other words, equivalent to having read the pack header start with
* `read_PS_packet_start`).
*
* If you want to call `read_PS_packet_start` to read this pack header start
* in again, then call ``seek_using_PS_reader(ps,posn)`` to reposition ready
* to read it.
*
* - `ps` is the PS read-ahead context we're reading from
* - if `verbose`, then the 00 00 01 XX sequences found will be logged
* to stderr, indicating the progress of our search
* - if `max` is non-zero, then it is the maximum number of bytes
* to scan before giving up.
* - `posn` is the file offset of the start of the packet found
*
* Returns:
* * 0 if it succeeds,
* * EOF if EOF is read, or an MPEG_program_end_code is read, or
* * 1 if some error (including the first 3 bytes not being 00 00 01) occurs.
*/
extern int find_PS_pack_header_start(PS_reader_p ps,
int verbose,
u_int32 max,
offset_t *posn)
{
int err;
byte stream_id = 0;
while (stream_id != 0xBA)
{
err = find_PS_packet_start(ps,verbose,max,posn,&stream_id);
if (err)
{
fprintf(stderr,"### Error looking for PS pack header (0xBA)\n");
return 1;
}
if (verbose)
{
fprintf(stderr," Found: stream id %02X at " OFFSET_T_FORMAT " (",
stream_id,*posn);
print_stream_id(stderr,stream_id);
fprintf(stderr,")\n");
}
}
return 0;
}
/*
* Read in (the rest of) a PS packet according to its length.
*
* Suitable for use reading PS PES packets and PS system header packets.
*
* NOTE that the `data` buffer in the `packet` is realloc'ed by this
* function. It is thus important to ensure that the `packet` datastructure
* contains a NULL pointer for said buffer before the first call of this
* function.
*
* - `ps` is the PS read-ahead context we're reading from
* - `stream_id` identifies what sort of packet it is
* - `packet` is the packet we're reading the PES packet into.
*
* Returns 0 if it succeeds, EOF if it unexpectedly reads end-of-file, and 1
* if some other error occurs. `packet->data` will be NULL if EOF is returned.
*/
extern int read_PS_packet_body(PS_reader_p ps,
byte stream_id,
PS_packet_p packet)
{
int err;
byte buf[2];
// First, the packet length
err = read_PS_bytes(ps,2,buf,NULL);
if (err)
{
fprintf(stderr,"### %s reading PS packet length\n",
(err==EOF?"Unexpected end of file":"Error"));
if (packet->data!=NULL) free(packet->data);
packet->data = NULL;
return err;
}
packet->packet_length = (buf[0] << 8) | buf[1];
#if DEBUG
printf("Packet length %d\n",packet->packet_length);
#endif
// Remember that the packet length is the length of data
// *after* the packet length field. Also, it is only allowed
// to be 0 within a Transport Stream, so it should never be 0 for us
// - but let's check anyway
if (packet->packet_length == 0)
{
fprintf(stderr,"### Packet has length 0 - not allowed in PS\n");
if (packet->data!=NULL) free(packet->data);
packet->data = NULL;
return 1;
}
// Since we are, in general, expecting to write the packet out again
// at some point, it is convenient to also store the leading bytes
#if 0 // XXX naughty stuff
packet->data = realloc(packet->data,packet->packet_length + 6 + 10);
#else
packet->data = realloc(packet->data,packet->packet_length + 6);
#endif
if (packet->data == NULL)
{
fprintf(stderr,"### Unable to allocate PS packet data buffer\n");
return 1;
}
packet->data_len = packet->packet_length + 6;
// So let us reestablish said leading bytes
packet->data[0] = 0;
packet->data[1] = 0;
packet->data[2] = 1;
packet->data[3] = stream_id;
packet->data[4] = buf[0];
packet->data[5] = buf[1];
// And now we can read in the rest of the packet's data
err = read_PS_bytes(ps,packet->packet_length,&(packet->data[6]),NULL);
if (err)
{
fprintf(stderr,"### %s reading rest of PS packet\n",
(err==EOF?"Unexpected end of file":"Error"));
if (packet->data!=NULL) free(packet->data);
packet->data = NULL;
return err;
}
#if 0 // XXX naughty stuff - add some trailing zero bytes
packet->data[packet->data_len + 0] = 0;
packet->data[packet->data_len + 1] = 0;
packet->data[packet->data_len + 2] = 0;
packet->data[packet->data_len + 3] = 0;
packet->data[packet->data_len + 4] = 0;
packet->data[packet->data_len + 5] = 0;
packet->data[packet->data_len + 6] = 0;
packet->data[packet->data_len + 7] = 0;
packet->data[packet->data_len + 8] = 0;
packet->data[packet->data_len + 9] = 0;
packet->packet_length += 10;
packet->data_len += 10;
#endif
return 0;
}
/*
* Read in the body of the pack header (but *not* the system header packets
* therein).
*
* - `ps` is the PS read-ahead context we're reading from
* - `hdr` is the packet we've read
*
* Returns 0 if it succeeds, EOF if it unexpectedly reads end-of-file, and
* 1 if some other error occurs.
*/
extern int read_PS_pack_header_body(PS_reader_p ps,
PS_pack_header_p hdr)
{
int err;
byte dummy[8]; // a 3 bit length means no more than 7 stuffing bytes
// Read just the first 8 bytes, in case it's an MPEG-1 pack header
err = read_PS_bytes(ps,8,hdr->data,NULL);
if (err)
{
fprintf(stderr,"### %s reading body of PS pack header\n",
(err==EOF?"Unexpected end of file":"Error"));
return err;
}
if ((hdr->data[0] & 0xF0) == 0x20)
{
#if DEBUG
printf("ISO/IEC 11171-1/MPEG-1 pack header\n");
print_data(stdout,"Pack header",hdr->data,8,8);
#endif
hdr->pack_stuffing_length = 0; // since it doesn't exist
hdr->scr =
(((u_int64)(hdr->data[0] & 0x09)) << 29) |
(((u_int64) hdr->data[1] ) << 22) |
(((u_int64)(hdr->data[2] & 0xFE)) << 14) |
(((u_int64) hdr->data[3] ) << 7) |
(((u_int64)(hdr->data[4] & 0xFE)) >> 1);
hdr->program_mux_rate =
(((u_int32)(hdr->data[5] & 0x7F)) << 15) |
(((u_int32) hdr->data[6] ) << 7) |
(((u_int32)(hdr->data[7] & 0xFE)) >> 1);
// In MPEG-1, SCR = NINT(SysClockFreq * t[i]) % 2**33
// where SysClockFreq = 90,000 Hz
//
// In H.222.0, SCR = SCRbase[i] * 300 + SCRext[i]
// = (((SysClockFreq * t[i]) DIV 300) % 2**33) * 300 +
// ((SysClockFreq * t[i]) DIV 1) % 300
// where SysClockFreq = 27,000,000 Hz
// Fudge these to match H.222.0 in case anyone tries to use them later on
hdr->scr = hdr->scr * 300;
hdr->scr_base = hdr->scr / 300;
hdr->scr_extn = 0; // i.e., hdr->scr % 300
}
else
{
#if DEBUG
printf("ISO/IEC 13818-1/H.222.0 pack header\n");
#endif
err = read_PS_bytes(ps,2,&(hdr->data[8]),NULL);
if (err)
{
fprintf(stderr,"### %s reading last 2 bytes of body of PS pack header\n",
(err==EOF?"Unexpected end of file":"Error"));
return err;
}
#if DEBUG
print_data(stdout,"Pack header",hdr->data,10,10);
#endif
hdr->scr_base =
(((u_int64)(hdr->data[0] & 0x38)) << 27) |
(((u_int64)(hdr->data[0] & 0x03)) << 28) |
(((u_int64) hdr->data[1] ) << 20) |
(((u_int64)(hdr->data[2] & 0xF8)) << 12) |
(((u_int64)(hdr->data[2] & 0x03)) << 13) |
(((u_int64) hdr->data[3] ) << 5) |
(((u_int64)(hdr->data[4] & 0xF8)) >> 3);
hdr->scr_extn =
(((u_int32)(hdr->data[4] & 0x03)) << 7) |
(((u_int32) hdr->data[5] ) >> 1);
hdr->scr = hdr->scr_base * 300 + hdr->scr_extn;
hdr->program_mux_rate =
(((u_int32)hdr->data[6] << 14)) |
(((u_int32)hdr->data[7] << 6)) |
(((u_int32)hdr->data[8] >> 2));
hdr->pack_stuffing_length = hdr->data[9] & 0x07;
}
#if DEBUG // XXX
printf("Pack header body: scr_base " LLU_FORMAT ", scr_extn %u, scr "
LLU_FORMAT ", mux rate %u, stuffing %d\n",
hdr->scr_base,hdr->scr_extn,hdr->scr,hdr->program_mux_rate,
hdr->pack_stuffing_length);
#endif
// And ignore that many stuffing bytes...
if (hdr->pack_stuffing_length > 0)
{
err = read_PS_bytes(ps,hdr->pack_stuffing_length,dummy,NULL);
if (err)
{
fprintf(stderr,"### %s reading PS pack header stuffing bytes\n",
(err==EOF?"Unexpected end of file":"Error"));
return err;
}
}
return 0;
}
/*
* Clear the contents of a PS packet datastructure. Frees the internal
* `data` array.
*/
extern void clear_PS_packet(PS_packet_p packet)
{
if (packet->data != NULL)
{
free(packet->data);
packet->data = NULL;
packet->data_len = 0;
}
packet->packet_length = 0;
}
/*
* Tidy up and free a PS packet datastructure after we've finished with it.
*
* Empties the PS packet datastructure, frees it, and sets `unit` to NULL.
*
* If `unit` is already NULL, does nothing.
*/
extern void free_PS_packet(PS_packet_p *packet)
{
if (*packet == NULL)
return;
clear_PS_packet(*packet);
free(*packet);
*packet = NULL;
}
/*
* Read in the start (the first 4 bytes) of the next program stream packet.
*
* If the bytes read don't appear to be valid (i.e., they do not start with
* the 00 00 01 prefix), then the next pack header will be sought and read in.
*
* Note that sequences of 00 bytes before the 00 00 01 will be ignored.
*
* - `ps` is the PS read-ahead context we're reading from
* - if `verbose`, then we want to explain what we're doing
* - `posn` is the file offset of the start of the packet
* - `stream_id` is the identifying byte, after the 00 00 01 prefix. Note
* that this is set correctly if MPEG_program_end_code was read, and is
* 0 if an error occurred.
*
* Returns:
* * 0 if it succeeds,
* * EOF if EOF is read, or an MPEG_program_end_code is read,
* * 2 if the bytes read are not 00 00 01 `stream_id`, or
* * 1 if some other error occurs.
*/
extern int read_PS_packet_start(PS_reader_p ps,
int verbose,
offset_t *posn,
byte *stream_id)
{
int err;
byte buf[4];
*stream_id = 0;
err = read_PS_bytes(ps,4,buf,posn);
if (err == EOF)
return EOF;
else if (err)
{
fprintf(stderr,"### Error reading start of PS packet\n");
return 1;
}
// It's not uncommon to get a sequence of 00 bytes between packs
// (in particular, after an audio pack). We don't really want to grumble
// about such things, but just to cope
if (buf[0] == 0 && buf[1] == 0 && buf[2] == 0)
{
#if 0 // XXX
printf("// %02x %02x %02x %02x\n",buf[0],buf[1],buf[2],buf[3]);
#endif
while (buf[2] == 0) // we already know buf[0] and buf[1] are zero
{
buf[2] = buf[3];
err = read_PS_bytes(ps,1,&(buf[3]),posn);
if (err == EOF)
return EOF;
else if (err)
{
fprintf(stderr,"### Error skipping 00 bytes before start of PS packet\n");
return 1;
}
}
#if 0 // XXX
printf("\\\\ %02x %02x %02x %02x\n",buf[0],buf[1],buf[2],buf[3]);
#endif
}
if (buf[0] != 0 || buf[1] != 0 || buf[2] != 1)
{
fprintf(stderr,"!!! PS packet at " OFFSET_T_FORMAT " should start "
"00 00 01, but instead found %02X %02X %02X\n",
*posn,buf[0],buf[1],buf[2]);
#if RECOVER_BROKEN_PS
fprintf(stderr,"!!! Attempting to find next PS pack header\n");
err = find_PS_pack_header_start(ps,TRUE,0,posn);
if (err == EOF)
return EOF;
else if (err)
{
fprintf(stderr,"### Error trying to find start of next pack header\n");
return 1;
}
fprintf(stderr,"!!! Continuing with PS pack header at " OFFSET_T_FORMAT
"\n",*posn);
*stream_id = 0xBA;
return 0;
#else
return 2;
#endif
}
*stream_id = buf[3];
#if DEBUG
printf("Packet at " OFFSET_T_FORMAT ", stream id %02X (",*posn,*stream_id);
print_stream_id(stdout,*stream_id);
printf(")\n");
#endif
if (buf[3] == 0xB9) // MPEG_program_end_code
{
if (verbose)
printf("Stopping at MPEG_program_end_code\n");
return EOF;
}
else
return 0;
}
/* Determine the details of an AC3 stream, by looking at its start
*
* Naughtily assume that `data` is long enough...
*/
static inline void determine_ac3_details(byte *data, int verbose,
byte *bsmod, byte *acmod)
{
// The end of the syncinfo
int fscod = (data[4] & 0xC0) >> 6;
int frmsizecode = (data[4] & 0x3F);
// The start of the bit stream info
int bsid = (data[5] & 0xF8) >> 3;
*bsmod = (data[5] & 0x07);
*acmod = (data[6] & 0xC0) >> 6;
if (verbose)
{
printf(" fscod %x (sample rate %skHz)\n",fscod,
(fscod==0?"48":fscod==1?"44.1":fscod==2?"32":"??"));
printf(" frmsizecode %x\n",frmsizecode);
printf(" bsid %x (%s)\n",bsid,
(bsid==8?"standard":bsid==6?"A52a alternate":
bsid<8?"standard subset":"???"));
printf(" bsmod %x (%s)\n",*bsmod,BSMOD_STR(*bsmod,*acmod));
printf(" acmod %x (%s)\n",*acmod,ACMOD_STR(*acmod));
}
}
/*
* Inspect the given PS packet, and determine if it contains AC3 or DTS audio data.
*
* - `packet` is the packet's data, already established as private_data_1
* - `is_dvd` is true if the data should be interpreted as DVD data
* - if `verbose`, report on the details of what we find out
* - `substream_index` returns the substream's index, taken from the low
* nibble of the substream id, and adjusted to start at 0. This will be
* a value in the range 0-7 for DTS, AC3 and LPCM, and in the range 0-1F
* (0-31) for subpictures.
* - for AC3, `bsmod` and `acmod` return the appropriate quantities,
* otherwise they are 0.
*
* Returns one of the SUBSTREAM_* values.
*/
extern int identify_private1_data(struct PS_packet *packet,
int is_dvd,
int verbose,
int *substream_index,
byte *bsmod,
byte *acmod)
{
// If this packet contains the start of a data packet, then
// try to determine if it is AC-3
int PES_header_data_length = packet->data[6+2];
int what = SUBSTREAM_OTHER;
byte *data;
#if 0 // Hmm - the data never does seem to have the pusi bit set
if (verbose)
{
int data_alignment_indicator = (packet->data[6] & 0x04);
if (data_alignment_indicator)
printf("*** Data aligned\n");
else
printf("--- Data not aligned\n");
printf("*** PES header data length 0x%x (%d)\n",
PES_header_data_length,PES_header_data_length);
}
#endif
*substream_index = 0;
*bsmod = 0;
*acmod = 0;
// This *should* be the start of the underlying packet
// Note that PES_header_data_length should not be 0 for
// non-video streams...
data = packet->data + 6 + 3 + PES_header_data_length;
// DVD data has some structure within private_stream_1
if (is_dvd)
{
int substream_id, frame_count, offset;
substream_id = data[0];
frame_count = data[1];
offset = (data[2] << 8) | data[3];
if (0x20 <= substream_id && substream_id <= 0x3F)
{
what = SUBSTREAM_SUBPICTURES;
*substream_index = substream_id - 0x20;
}
else if (0x80 <= substream_id && substream_id <= 0x87)
{
what = SUBSTREAM_AC3;
*substream_index = substream_id - 0x80;
}
else if (0x88 <= substream_id && substream_id <= 0x8F)
{
what = SUBSTREAM_DTS;
*substream_index = substream_id - 0x88;
}
else if (0xA0 <= substream_id && substream_id <= 0xA7)
{
what = SUBSTREAM_LPCM;
*substream_index = substream_id - 0xA0;
}
if (verbose)
{
printf(">>> substream_id %02x (%s index %d)\n",substream_id,
(what==SUBSTREAM_AC3?"AC3":
what==SUBSTREAM_DTS?"DTS":
what==SUBSTREAM_LPCM?"LPCM":
what==SUBSTREAM_SUBPICTURES?"subpictures":"???"),
*substream_index);
printf(">>> frame_count %02x (%d)\n",frame_count,frame_count);
printf(">>> offset %04x (%d)\n",offset,offset);
}
// For AC3 and DTS, it's easy to check that it *does* appear to be what it
// says, so let's do so
if (what == SUBSTREAM_AC3 || what == SUBSTREAM_DTS)
{
int packet_length = (packet->data[4] << 8) | packet->data[5];
byte *sub_data = data + 3 + offset;
// Roughly check if the offset looks plausible
// TODO: make this check more robust!
if (sub_data >= packet->data + packet_length) // leave off the + 6
{
// Looks like it's a silly offset, so probably NOT what we want
if (verbose)
printf("*** expected %s, but data at %p is beyond"
" packet->end at %p\n",(what==SUBSTREAM_DTS?"DTS":"AC3"),
sub_data,packet->data+6+packet_length);
what = SUBSTREAM_ERROR; // we definitely mustn't try to interpret it!
}
else if (what == SUBSTREAM_AC3 &&
!(sub_data[0] == 0x0B && sub_data[1] == 0x77))
{
printf("*** expected AC3 sync 0x0B77, but found 0x%02x%02x\n",
sub_data[0],sub_data[1]);
what = SUBSTREAM_ERROR;
}
else if (what == SUBSTREAM_DTS &&
!(sub_data[0] == 0x7F && sub_data[1] == 0xFE &&
sub_data[2] == 0x80 && sub_data[3] == 0x01))
{
printf("*** expected DTS sync 0x7FFE8001,"
" but found 0x%02x%02x%02x%02x\n",
sub_data[0],sub_data[1],sub_data[2],sub_data[3]);
what = SUBSTREAM_ERROR;
}
if (what == SUBSTREAM_AC3)
determine_ac3_details(sub_data,verbose,bsmod,acmod);
}
}
else
{
// For non-DVD data, we have to decide for ourselves what we've got
if (data[0] == 0x0B && data[1] == 0x77)
{
what = SUBSTREAM_AC3;
determine_ac3_details(data,verbose,bsmod,acmod);
}
else if (data[0] == 0x7F && data[1] == 0xFE &&
data[2] == 0x80 && data[3] == 0x01)
what = SUBSTREAM_DTS;
}
if (verbose)
{
switch (what)
{
case SUBSTREAM_AC3:
printf("*** Looks like AC3\n");
break;
case SUBSTREAM_DTS:
printf("*** Looks like DTS\n");
break;
case SUBSTREAM_LPCM:
printf("*** Looks like LPCM\n");
break;
case SUBSTREAM_SUBPICTURES:
printf("*** Looks like sub-pictures\n");
break;
case SUBSTREAM_OTHER:
printf("*** Other substream: %02x %02x %02x %02x\n",
data[0],data[1],data[2],data[3]);
break;
default:
printf("*** Error recognising substream: %02x %02x %02x %02x\n",
data[0],data[1],data[2],data[3]);
break;
}
}
return what;
}
// ============================================================
// PS to TS functions
// ============================================================
/*
* Write out a video packet
*
* - `output` is the transport stream we're writing to
* - `header` is the data from the PS pack header, including its SCR data
* - `stream_id` is the stream id of the PS packet we're writing
* - `packet` is the PS packet itself
* - `prog_data` is the programming information we're using
* - `num_video_ignored` will be be updated if we ignore this video packet
* - `num_video_written` will be updated if we don't
* - if `verbose` then we want to output diagnostic information
* - if `quiet` then we want to be as quiet as we can
*
* Returns 0 if all went well, 1 if something went wrong.
*/
static int write_video(TS_writer_p output,
struct PS_pack_header *header,
byte stream_id,
struct PS_packet *packet,
struct program_data *prog_data,
int *num_video_ignored,
int *num_video_written,
int verbose,
int quiet)
{
int err;
// Unless the user has requested a particular video stream, we want
// to use the first we find...
// (For DVD this should also be the only stream, since DVD only allows
// one video stream, but that's not for us to check.)
if (prog_data->video_stream == -1)
{
prog_data->video_stream = stream_id;
}
else if (stream_id != prog_data->video_stream)
{
static int ignored_stream[NUMBER_VIDEO_STREAMS] = {0};
int this_stream = stream_id & 0x0F;
if (!ignored_stream[this_stream])
{
ignored_stream[this_stream] = TRUE;
if (!quiet)
printf("Ignoring video stream 0x%x (%d)\n",this_stream,this_stream);
}
(*num_video_ignored) ++;
return 0;
}
if (*num_video_written == 0)
{
if (!quiet)
printf("Video: stream %d, PID 0x%03x, stream type 0x%02x\n"
" %s\n",
stream_id & 0x0F,prog_data->video_pid,prog_data->video_type,
H222_STREAM_TYPE_STR(prog_data->video_type));
err = add_stream_to_pmt(prog_data->pmt,prog_data->video_pid,
prog_data->video_type,0,NULL);
if (err) return 1;
prog_data->pmt->version_number ++;
// And it makes sense to write out our (updated) program
// information before we write out the first packet of
// the new video (!)
err = write_pat_and_pmt(output,
prog_data->transport_stream_id,
prog_data->prog_list,
prog_data->pmt_pid,
prog_data->pmt);
if (err)
{
fprintf(stderr,
"### Error writing TS program data before video packet\n");
return 1;
}
}
// This is our video stream - output it as such
err = write_PES_as_TS_PES_packet(output,packet->data,packet->data_len,
prog_data->video_pid,
DEFAULT_VIDEO_STREAM_ID,
TRUE,header->scr_base,header->scr_extn);
if (err) return 1;
(*num_video_written) ++;
if (verbose)
{
printf("v");
fflush(stdout);
}
return 0;
}
/*
* Write out the data for our DVD private_stream_1 audio packet
*
* - `output` is the transport stream we're writing to
* - `packet` is the PS packet itself
* - `prog_data` is the programming information we're using
*
* Returns 0 if all went well, 1 if something went wrong.
*/
static int write_DVD_AC3_data(TS_writer_p output,
struct PS_packet *packet,
struct program_data *prog_data)
{
// DVD private_stream_1 is packaged as substreams - we need to unpack
// it before we output it
// Basically, looking at the substream offset:
// 0 means there is no first frame in this packet (i.e., the data
// is the middle/end of a frame
// 1 means the data *starts* with the first frame (to which any
// PTS applies)
// N means that the frame to which the PTS applies starts at
// offset N-1
int PES_header_data_length = packet->data[6+2];
byte *data = packet->data + 6 + 3 + PES_header_data_length;
int data_len = packet->data_len - 6 - 3 - PES_header_data_length;
//int substream_id = data[0];
int frame_count = data[1]; // frames starting in this packet
int offset = (data[2] << 8) | data[3];
// If there is no PTS in this packet, do we need to split, even
// if the offset is > 1? I'll assume not...
int got_pts;
u_int64 pts;
int PES_packet_length = (packet->data[4] << 8) | packet->data[5];
int err = find_PTS_in_PES(packet->data,packet->data_len,&got_pts,&pts);
if (err)
{
fprintf(stderr,"### Error looking for PTS in PES packet\n");
return 1;
}
#if DEBUG_AC3
printf(".. frame_count=%d, offset=%4d, got_pts=%d ",
frame_count,offset,got_pts);
if (frame_count > 0 && offset > 0)
{
if (data[offset+3]==0x0B && data[offset+4]==0x77)
printf("(frame is AC3)\n");
else
printf("(frame appears to start %02x %02x)\n",
data[offset+3],data[offset+4]);
}
#endif
if (frame_count == 0 || offset <= 1 || !got_pts)
{
// We can output the data from this packet "unsplit".
// However, first we need to create a new packet that does not
// contain the DVD substream header - this is most easily done
// by (a) copying the audio data bytes "down" over the header
// we want to lose, and (b) adjusting the various packet length
// fields appropriately
#if DEBUG_AC3
printf("move data down 4, leaving %4d\n",data_len-4);
#endif
(void) memmove(data,data+4,data_len-4); // 4 bytes of substream header
// After copying, need to remember to adjust the packet length
PES_packet_length -= 4; // still 4 bytes of substream header
packet->data[4] = (PES_packet_length & 0xFF00) >> 8;
packet->data[5] = (PES_packet_length & 0x00FF);
// And we then have something suitable for outputting as-is
err = write_PES_as_TS_PES_packet(output,packet->data,packet->data_len-4,
prog_data->audio_pid,
PRIVATE1_AUDIO_STREAM_ID,
FALSE,0,0);
if (err) return 1;
}
else
{
// We need to output the data *before* the "first" packet
// in a plain PES packet, by itself, and then output the
// packet to which the PTS applies as a separate PES packet.
#if DEBUG_AC3
printf("write first %4d bytes, then move data down %4d, leaving %4d\n",
offset-1,3+offset,data_len-3-offset);
#endif
// First, the part before the first packet...
err = write_ES_as_TS_PES_packet(output,data+4,offset-1,
prog_data->audio_pid,
PRIVATE1_AUDIO_STREAM_ID);
if (err) return 1;
// And we can then do the "move the data down" trick
// Remember that offset 1 means the first byte after the substream
// header, which we would normally expect to be offset 0...
(void) memmove(data,data+3+offset,data_len-3-offset);
// After copying, need to remember to adjust the packet length
PES_packet_length -= 3 + offset;
packet->data[4] = (PES_packet_length & 0xFF00) >> 8;
packet->data[5] = (PES_packet_length & 0x00FF);
// And we then have something suitable for outputting as-is
err = write_PES_as_TS_PES_packet(output,packet->data,
packet->data_len-3-offset,
prog_data->audio_pid,
PRIVATE1_AUDIO_STREAM_ID,
FALSE,0,0);
if (err) return 1;
}
return 0;
}
/*
* Write out an audio packet
*
* - `output` is the transport stream we're writing to
* - `stream_id` is the stream id of the PS packet we're writing
* - `packet` is the PS packet itself
* - `prog_data` is the programming information we're using
* - `num_audio_ignored` will be be updated if we ignore this audio packet
* - `num_audio_written` will be updated if we don't
* - if `verbose` then we want to output diagnostic information
* - if `quiet` then we want to be as quiet as we can
*
* Returns 0 if all went well, 1 if something went wrong.
*/
static int write_audio(TS_writer_p output,
byte stream_id,
struct PS_packet *packet,
struct program_data *prog_data,
int *num_audio_ignored,
int *num_audio_written,
int verbose,
int quiet)
{
int err;
int substream_index = -1;
byte bsmod = 0xFF;
byte asmod = 0xFF;
int is_h222_pes = IS_H222_PES(packet->data);
// For MPEG audio, unless the user has requested a particular audio stream,
// we want to use the first we find.
// For AC3, we only want audio from the requested substream
// (DVD allows up to 8 audio streams, but we're only outputting one.
//
// Note that we assume that any audio data using private stream 1 to
// transmit DVD-style audio packets will also be using PES (H.222.0)
// packeting - i.e., *not* using MPEG-1 packets. This allows the code
// to "dissect" DVD audio packets to be simpler, and seems a reasonable
// assumption.
if (prog_data->audio_stream == -1) // take the first audio stream we find...
{
if (stream_id == PRIVATE1_AUDIO_STREAM_ID && is_h222_pes)
{
// Find out what type of data this is
int what = identify_private1_data(packet,prog_data->is_dvd,verbose,
&substream_index,&bsmod,&asmod);
if (what != SUBSTREAM_AC3)
{
// We're not interested in it
return 0;
}
prog_data->audio_stream = stream_id;
prog_data->audio_substream = substream_index; // only meaningful for DVD
}
else // some other ("normal") audio stream
prog_data->audio_stream = stream_id;
}
else if (stream_id != prog_data->audio_stream)
{
if (!quiet)
{
static int ignored_stream[NUMBER_AUDIO_STREAMS] = {0};
int this_stream = stream_id & 0x1F;
if (!ignored_stream[this_stream])
{
ignored_stream[this_stream] = TRUE;
printf("Ignoring audio stream 0x%x (%d)\n",this_stream,this_stream);
}
}
(*num_audio_ignored) ++;
return 0;
}
else if (prog_data->is_dvd &&
stream_id == PRIVATE1_AUDIO_STREAM_ID &&
prog_data->audio_stream == PRIVATE1_AUDIO_STREAM_ID &&
is_h222_pes)
{
// Check if this is the right substream
int what = identify_private1_data(packet,prog_data->is_dvd,verbose,
&substream_index,&bsmod,&asmod);
if (what != SUBSTREAM_AC3)
{
if (!quiet)
{
#define MAX_IGNORED_NON_AC3 10 // report the first 10 substreams we're ignoring
static u_int32 ignored_non_AC3[MAX_IGNORED_NON_AC3] = {0};
u_int32 lookfor = (what << 16) | substream_index;
int ii;
for (ii = 0; ii < MAX_IGNORED_NON_AC3; ii++)
{
if (ignored_non_AC3[ii] == lookfor)
break; // we've reported it before
else if (ignored_non_AC3[ii] == 0)
{
// We've not reported it before, and have room to remember it
ignored_non_AC3[ii] = lookfor;
printf("Ignoring %sprivate_stream_1 substream 0x%x (%d)"
" containing %s\n",
(SUBSTREAM_IS_AUDIO(what)?"":"non-audio "),
substream_index,substream_index,SUBSTREAM_STR(what));
break;
}
}
}
if (SUBSTREAM_IS_AUDIO(what))
(*num_audio_ignored) ++;
return 0;
}
else if (substream_index != prog_data->audio_substream)
{
if (!quiet)
{
static int ignored_ac3_substream[NUMBER_AC3_SUBSTREAMS] = {0};
if (!ignored_ac3_substream[substream_index])
{
ignored_ac3_substream[substream_index] = TRUE;
printf("Ignoring private_stream_1 substream 0x%x (%d) "
"containing AC3\n",substream_index,substream_index);
}
}
(*num_audio_ignored) ++;
return 0;
}
}
if (*num_audio_written == 0)
{
byte audio_stream_type;
if (stream_id == PRIVATE1_AUDIO_STREAM_ID)
{
if (prog_data->output_dolby_as_dvb)
audio_stream_type = DVB_DOLBY_AUDIO_STREAM_TYPE;
else
audio_stream_type = ATSC_DOLBY_AUDIO_STREAM_TYPE;
}
else
audio_stream_type = MPEG2_AUDIO_STREAM_TYPE;
if (!quiet)
{
if (stream_id == PRIVATE1_AUDIO_STREAM_ID)
{
printf("Audio: private stream 1,");
if (prog_data->is_dvd && is_h222_pes)
printf(" substream %d,",prog_data->audio_substream);
printf(" PID 0x%03x, AC-3 (Dolby)\n",prog_data->audio_pid);
printf(" %s\n audio coding mode %s\n",
BSMOD_STR(bsmod,asmod),ACMOD_STR(asmod));
}
else
{
printf("Audio: stream %d, PID 0x%03x, stream type 0x%02x = %s\n",
stream_id & 0x1F,prog_data->audio_pid,audio_stream_type,
H222_STREAM_TYPE_STR(audio_stream_type));
}
}
if (audio_stream_type == DVB_DOLBY_AUDIO_STREAM_TYPE)
{
byte desc[] = {0x6A, 0x01, 0x00};
int desc_len = 3;
err = add_stream_to_pmt(prog_data->pmt,prog_data->audio_pid,
audio_stream_type,desc_len,desc);
}
else if (audio_stream_type == ATSC_DOLBY_AUDIO_STREAM_TYPE)
{
byte desc[] = {0x05, 0x04, 0x41, 0x43, 0x2D, 0x33};
int desc_len = 6;
err = add_stream_to_pmt(prog_data->pmt,prog_data->audio_pid,
audio_stream_type,desc_len,desc);
}
else
err = add_stream_to_pmt(prog_data->pmt,prog_data->audio_pid,
audio_stream_type,0,NULL);
if (err) return 1;
prog_data->pmt->version_number ++;
// And it makes sense to write out our (updated) program
// information before we write out the first packet of
// the new audio
err = write_pat_and_pmt(output,
prog_data->transport_stream_id,
prog_data->prog_list,
prog_data->pmt_pid,
prog_data->pmt);
if (err)
{
fprintf(stderr,
"### Error writing TS program data before audio packet\n");
return 1;
}
}
if (prog_data->is_dvd && stream_id == PRIVATE1_AUDIO_STREAM_ID &&
is_h222_pes)
{
// Unpack the DVD substreams before outputting them
err = write_DVD_AC3_data(output,packet,prog_data);
if (err) return 1;
}
else
{
err = write_PES_as_TS_PES_packet(output,packet->data,packet->data_len,
prog_data->audio_pid,
(prog_data->want_ac3?
PRIVATE1_AUDIO_STREAM_ID:
DEFAULT_AUDIO_STREAM_ID),
FALSE,0,0);
if (err) return 1;
}
(*num_audio_written) ++;
if (verbose)
{
printf("a");
fflush(stdout);
}
return 0;
}
/*
* Read program stream and write transport stream
*
* - `ps` is the program stream
* - `output` is the transport stream
* - `pad_start` is the number of filler TS packets to start the output
* with.
* - `program_repeat` is how often (after how many PS packs) to repeat
* the program information (PAT/PMT)
* - `is_dvd` should be true if this input represents DVD data; i.e., with
* private_stream_1 used for AC-3/DTS/etc., and with substream headers
* therein.
* - `video_stream` indicates which video stream we want - i.e., the stream
* with id 0xE0 + <video_stream>. -1 means the first encountered.
* - `audio_stream` indicates which audio stream we want. If `want_ac3_audio`
* is false, then this will be the stream with id 0xC0 + <audio_stream>,
* or -1 for the first audio stream encountered.
* - if `want_ac3_audio` is true, then if `is_dvd` is true, then we want
* audio from private_stream_1 (0xBD) with substream id <audio_stream>,
* otherwise we ignore `audio_stream` and assume that all data in
* private_stream_1 is the audio we want.
* - `output_dolby_as_dvb` should be true if Dolby (AC-3) audio (if selected) should
* be output using the DVB stream type 0x06, false if using the ATSC stream
* type 0x81. This is ignored if the audio being output is not Dolby.
* - `pmt_pid` is the PID of the PMT to write
* - `pcr_pid` is the PID of the TS unit containing the PCR
* - `video_pid` is the PID for the video we write
* - `keep_audio` is true if the audio stream should be output, false if
* it should be ignored
* - `audio_pid` is the PID for the audio we write
* - if `max` is non-zero, then we want to stop reading after we've read
* `max` packs
* - if `verbose` then we want to output diagnostic information
* - if `quiet` then we want to be as quiet as we can
*
* Returns 0 if all went well, 1 if something went wrong.
*/
static int _ps_to_ts(PS_reader_p ps,
TS_writer_p output,
struct program_data *prog_data,
int pad_start,
int program_repeat,
int keep_audio,
int max,
int verbose,
int quiet)
{
int ii, err;
offset_t posn = 0; // The location in the input file of the current packet
int count = 0; // Number of PS packets
byte stream_id; // The packet's stream id
int end_of_file = FALSE;
// Summary data
int num_packs = 0;
int num_audio_written = 0;
int num_video_written = 0;
int num_video_ignored = 0;
int num_audio_ignored = 0;
struct PS_packet packet = {0};
struct PS_pack_header header = {0};
// Start off our output with some null packets - this is in case the
// reader needs some time to work out its byte alignment before it starts
// looking for 0x47 bytes
for (ii=0; ii<pad_start; ii++)
{
err = write_TS_null_packet(output);
if (err) return 1;
}
if (!quiet)
printf("Writing transport stream id 1, PMT PID 0x%02x, PCR PID 0x%02x\n",
prog_data->pmt_pid,prog_data->pcr_pid);
// Read the start of the first packet (we confidently expect this
// to be a pack header)
err = read_PS_packet_start(ps,verbose,&posn,&stream_id);
if (err == EOF)
{
fprintf(stderr,"### Error reading first pack header\n");
fprintf(stderr," Unexpected end of PS at start of stream\n");
return 1;
}
else if (err)
{
fprintf(stderr,"### Error reading first pack header\n");
return 1;
}
count ++;
if (stream_id != 0xba)
{
fprintf(stderr,"### Program stream does not start with pack header\n");
fprintf(stderr," First packet has stream id %02X (",stream_id);
print_stream_id(stderr,stream_id);
fprintf(stderr,")\n");
return 1;
}
// But given that, we can now happily loop reading in packs
// I *think* using this macro makes the code marginally more readable,
// and it helps emphasise that the code *is* identical each time
#define READ_NEXT_PS_PACKET_START \
err = read_PS_packet_start(ps,FALSE,&posn,&stream_id); \
if (err == EOF) \
{ \
end_of_file = TRUE; \
break; \
} \
else if (err) \
return 1; \
count ++;
for (;;)
{
int num_system_headers = 0;
if (max > 0 && num_packs >= max)
{
if (verbose)
printf("Stopping after %d packs\n",num_packs);
return 0;
}
num_packs ++;
// Write out our program data every so often, to give the reader
// a chance to resynchronise with our program stream
if (num_packs % program_repeat == 0)
{
if (verbose)
{
printf("PGM");
fflush(stdout);
}
err = write_pat_and_pmt(output,
prog_data->transport_stream_id,
prog_data->prog_list,
prog_data->pmt_pid,
prog_data->pmt);
if (err)
{
fprintf(stderr,"### Error writing out TS program data\n");
return 1;
}
}
err = read_PS_pack_header_body(ps,&header);
if (err)
{
fprintf(stderr,
"### Error reading data for pack header starting at "
OFFSET_T_FORMAT "\n",posn);
return 1;
}
// Look at the start of the next packet
READ_NEXT_PS_PACKET_START;
// If it's a system header, ignore it
if (stream_id == 0xbb)
{
err = read_PS_packet_body(ps,stream_id,&packet);
if (err)
{
fprintf(stderr,
"### Error reading system header starting at "
OFFSET_T_FORMAT "\n",posn);
return 1;
}
num_system_headers ++;
READ_NEXT_PS_PACKET_START;
}
if (end_of_file)
break;
// Then read the data packets
while (stream_id != 0xba) // i.e., until the start of the next pack
{
err = read_PS_packet_body(ps,stream_id,&packet);
if (err)
{
fprintf(stderr,"### Error reading PS packet starting at "
OFFSET_T_FORMAT "\n",posn);
return 1;
}
if (IS_AUDIO_STREAM_ID(stream_id))
{
if (keep_audio)
{
err = write_audio(output,stream_id,&packet,prog_data,
&num_audio_ignored,&num_audio_written,
verbose,quiet);
if (err)
{
fprintf(stderr,"### Error writing audio packet at "
OFFSET_T_FORMAT " to TS\n",posn);
return 1;
}
}
}
else if (IS_VIDEO_STREAM_ID(stream_id))
{
err = write_video(output,&header,stream_id,&packet,prog_data,
&num_video_ignored,&num_video_written,verbose,quiet);
if (err)
{
fprintf(stderr,"### Error writing video packet at " OFFSET_T_FORMAT
" to TS\n",posn);
return 1;
}
}
else if (verbose)
{
// For the moment, we ignore program stream map (0xBC) and
// program stream directory (0xFF), and indeed everything else
}
READ_NEXT_PS_PACKET_START;
}
if (end_of_file)
break;
}
clear_PS_packet(&packet);
if (verbose) printf("\n");
if (!quiet)
{
printf("Packets (total): %6d\n",count);
printf("Packs: %6d\n",num_packs);
printf("Video packets written: %6d\n",num_video_written);
printf("Audio packets written: %6d\n",num_audio_written);
if (num_video_ignored > 0)
printf("Video packets ignored: %6d\n",num_video_ignored);
if (num_audio_ignored > 0)
printf("Audio packets ignored: %6d\n",num_audio_ignored);
}
return 0;
}
/*
* Read program stream and write transport stream
*
* - `ps` is the program stream
* - `output` is the transport stream
* - `pad_start` is the number of filler TS packets to start the output
* with.
* - `program_repeat` is how often (after how many PS packs) to repeat
* the program information (PAT/PMT)
* - `video_type` indicates what type of video is being transferred. It should
* be VIDEO_H264, VIDEO_H262, etc.
* - `is_dvd` should be true if this input represents DVD data; i.e., with
* private_stream_1 used for AC-3/DTS/etc., and with substream headers
* therein.
* - `video_stream` indicates which video stream we want - i.e., the stream
* with id 0xE0 + <video_stream>. -1 means the first encountered.
* - `audio_stream` indicates which audio stream we want. If `want_ac3_audio`
* is false, then this will be the stream with id 0xC0 + <audio_stream>,
* or -1 for the first audio stream encountered.
* - if `want_ac3_audio` is true, then if `is_dvd` is true, then we want
* audio from private_stream_1 (0xBD) with substream id <audio_stream>,
* otherwise we ignore `audio_stream` and assume that all data in
* private_stream_1 is the audio we want.
* - `output_dolby_as_dvb` should be true if Dolby (AC-3) audio (if selected) should
* be output using the DVB stream type 0x06, false if using the ATSC stream
* type 0x81. This is ignored if the audio being output is not Dolby.
* - `pmt_pid` is the PID of the PMT to write
* - `pcr_pid` is the PID of the TS unit containing the PCR
* - `video_pid` is the PID for the video we write
* - `keep_audio` is true if the audio stream should be output, false if
* it should be ignored
* - `audio_pid` is the PID for the audio we write
* - if `max` is non-zero, then we want to stop reading after we've read
* `max` packs
* - if `verbose` then we want to output diagnostic information
* - if `quiet` then we want to be as quiet as we can
*
* Returns 0 if all went well, 1 if something went wrong.
*/
extern int ps_to_ts(PS_reader_p ps,
TS_writer_p output,
int pad_start,
int program_repeat,
int video_type,
int is_dvd,
int video_stream,
int audio_stream,
int want_ac3_audio,
int output_dolby_as_dvb,
u_int32 pmt_pid,
u_int32 pcr_pid,
u_int32 video_pid,
int keep_audio,
u_int32 audio_pid,
int max,
int verbose,
int quiet)
{
int err;
struct program_data prog_data = {0};
prog_data.transport_stream_id = 1;
prog_data.program_number = 1;
prog_data.pmt_pid = pmt_pid;
prog_data.pcr_pid = pcr_pid;
prog_data.video_pid = video_pid;
prog_data.audio_pid = audio_pid;
prog_data.video_type = video_type;
prog_data.output_dolby_as_dvb = output_dolby_as_dvb;
prog_data.video_stream = video_stream;
prog_data.want_ac3 = want_ac3_audio;
prog_data.is_dvd = is_dvd;
if (want_ac3_audio)
{
prog_data.audio_stream = PRIVATE1_AUDIO_STREAM_ID;
if (is_dvd)
prog_data.audio_substream = audio_stream;
else
prog_data.audio_substream = -1; // use the first we find
}
else
prog_data.audio_stream = audio_stream;
// We have one program - we'll make it program 1
#define PROGRAM_NUMBER 1
err = build_pidint_list(&prog_data.prog_list);
if (err) return 1;
err = append_to_pidint_list(prog_data.prog_list,pmt_pid,PROGRAM_NUMBER);
if (err)
{
free_pidint_list(&prog_data.prog_list);
return 1;
}
prog_data.pmt = build_pmt(PROGRAM_NUMBER,0,pcr_pid);
if (err)
{
free_pidint_list(&prog_data.prog_list);
return 1;
}
err = _ps_to_ts(ps,output,&prog_data,pad_start,program_repeat,keep_audio,
max,verbose,quiet);
if (err)
{
free_pidint_list(&prog_data.prog_list);
free_pmt(&prog_data.pmt);
return 1;
}
free_pidint_list(&prog_data.prog_list);
free_pmt(&prog_data.pmt);
return 0;
}
// Local Variables:
// tab-width: 8
// indent-tabs-mode: nil
// c-basic-offset: 2
// End:
// vim: set tabstop=8 shiftwidth=2 expandtab: