stv0g/tvheadend
1
0
Fork 0
Code Issues Pull requests Releases Wiki Activity

Initial support for AAC LATM (still not finished)

Browse source
This commit is contained in:
Andreas Öman 2009-08-10 17:18:17 +00:00
parent f8f80484c2
commit 9769156004
5 changed files with 317 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
Makefile
View file

@ -50,6 +50,7 @@ SRCS = src/main.c \
src/psi.c \
src/parsers.c \
src/parser_h264.c \
src/parser_latm.c \
src/tsdemux.c \
src/bitstream.c \
src/htsp.c \

191
src/parser_latm.c Normal file
View file

@ -0,0 +1,191 @@
/*
* LATM / AAC Parser
*
* Copyright (C) 2009 Andreas Öman
*
* Based on LATM Parser patch sent to ffmpeg-devel@
* copyright (c) 2009 Paul Kendall <paul@kcbbs.gen.nz>
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "tvhead.h"
#include "parsers.h"
#include "parser_latm.h"
#include "bitstream.h"
static const int mpeg4audio_sample_rates[16] = {
96000, 88200, 64000, 48000, 44100, 32000,
24000, 22050, 16000, 12000, 11025, 8000, 7350
};
typedef struct latm_private {
int configured;
int audio_mux_version_A;
int frame_length_type;
int sample_rate_index;
int channel_config;
} latm_private_t;
static uint32_t
latm_get_value(bitstream_t *bs)
{
return read_bits(bs, read_bits(bs, 2) * 8);
}
static void
read_audio_specific_config(latm_private_t *latm, bitstream_t *bs)
{
int aot;
aot = read_bits(bs, 5);
if(aot != 2)
return;
latm->sample_rate_index = read_bits(bs, 4);
if(latm->sample_rate_index == 0xf)
return;
latm->channel_config = read_bits(bs, 4);
skip_bits(bs, 1); //framelen_flag
if(read_bits1(bs)) { // depends_on_coder
skip_bits(bs, 14); // delay
}
skip_bits(bs, 1); // ext_flag
}
static void
read_stream_mux_config(latm_private_t *latm, bitstream_t *bs)
{
int audio_mux_version = read_bits(bs, 1);
latm->audio_mux_version_A = 0;
if(audio_mux_version) // audioMuxVersion
latm->audio_mux_version_A = read_bits(bs, 1);
if(!latm->audio_mux_version_A) {
if(audio_mux_version)
latm_get_value(bs); // taraFullness
read_bits(bs, 1); // allStreamSameTimeFraming = 1
read_bits(bs, 6); // numSubFrames = 0
read_bits(bs, 4); // numPrograms = 0
// for each program (which there is only on in DVB)
read_bits(bs, 3); // numLayer = 0
// for each layer (which there is only on in DVB)
if (!audio_mux_version)
read_audio_specific_config(latm, bs);
else {
uint32_t ascLen = latm_get_value(bs);
abort(); // ascLen -= read_audio_specific_config(filter, gb);
skip_bits(bs, ascLen);
}
// these are not needed... perhaps
latm->frame_length_type = read_bits(bs, 3);
switch(latm->frame_length_type) {
case 0:
read_bits(bs, 8);
break;
case 1:
read_bits(bs, 9);
break;
case 3:
case 4:
case 5:
read_bits(bs, 6); // celp_table_index
break;
case 6:
case 7:
read_bits(bs, 1); // hvxc_table_index
}
if (read_bits(bs, 1)) { // other data?
if (audio_mux_version)
latm_get_value(bs); // other_data_bits
else {
int esc;
do {
esc = read_bits(bs, 1);
read_bits(bs, 8);
} while (esc);
}
}
if (read_bits(bs, 1)) // crc present?
read_bits(bs, 8); // config_crc
}
}
/**
* Parse AAC LATM
*/
void
parse_latm_audio_mux_element(th_transport_t *t, th_stream_t *st, uint8_t *data,
int len)
{
latm_private_t *latm;
bitstream_t bs;
int slot_len, tmp;
init_bits(&bs, data, len);
if((latm = st->st_priv) == NULL)
latm = st->st_priv = calloc(1, sizeof(latm_private_t));
if(!read_bits1(&bs)) {
latm->configured = 1;
read_stream_mux_config(latm, &bs);
}
if(!latm->configured)
return;
if(latm->frame_length_type != 0)
return;
slot_len = 0;
do {
tmp = read_bits(&bs, 8);
slot_len += tmp;
} while (tmp == 255);
printf("TYPE = %d, muxslotlen = %d\n",
read_bits(&bs, 3), slot_len);
}

26
src/parser_latm.h Normal file
View file

@ -0,0 +1,26 @@
/*
* Packet parsing functions
* Copyright (C) 2007 Andreas Öman
*
* 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 3 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 General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef PARSER_LATM_H_
#define PARSER_LATM_H_
void
parse_latm_audio_mux_element(th_transport_t *t, th_stream_t *st, uint8_t *data,
int len);
#endif /* PARSER_LATM_H_ */

98
src/parsers.c
View file

@ -28,6 +28,7 @@
#include "tvhead.h"
#include "parsers.h"
#include "parser_h264.h"
#include "parser_latm.h"
#include "bitstream.h"
#include "packet.h"
#include "transports.h"
@ -85,6 +86,9 @@ static void parse_video(th_transport_t *t, th_stream_t *st, uint8_t *data,
static void parse_audio(th_transport_t *t, th_stream_t *st, uint8_t *data,
int len, int start, aparser_t *vp);
static void parse_aac(th_transport_t *t, th_stream_t *st, uint8_t *data,
int len, int start);
static void parse_mpegaudio(th_transport_t *t, th_stream_t *st, th_pkt_t *pkt);
static void parse_ac3(th_transport_t *t, th_stream_t *st, th_pkt_t *pkt);
@ -137,6 +141,11 @@ parse_raw_mpeg(th_transport_t *t, th_stream_t *st, uint8_t *data,
case SCT_AC3:
parse_audio(t, st, data, len, start, parse_ac3);
break;
case SCT_AAC:
if(0) // not yet
parse_aac(t, st, data, len, start);
break;
default:
break;
@ -144,6 +153,95 @@ parse_raw_mpeg(th_transport_t *t, th_stream_t *st, uint8_t *data,
}
/**
* Parse AAC LATM
*/
static void
parse_aac(th_transport_t *t, th_stream_t *st, uint8_t *data,
int len, int start)
{
int l, muxlen, p;
if(start) {
int i;
if(0)for(i = 0; i < st->st_buffer_ptr - 2; i++) {
if(st->st_buffer[i] == 0x56 && (st->st_buffer[i + 1] & 0xe0) == 0xe0) {
muxlen = (st->st_buffer[i + 1] & 0x1f) << 8 |
st->st_buffer[i + 2];
printf("AAC Sync at %8d: %8d bytes, next at %d\n", i, muxlen + 3,
i + muxlen + 3);
}
}
/* Payload unit start */
st->st_parser_state = 1;
st->st_buffer_ptr = 0;
st->st_parser_ptr = 0;
}
if(st->st_parser_state == 0)
return;
if(st->st_buffer == NULL) {
st->st_buffer_size = 4000;
st->st_buffer = malloc(st->st_buffer_size);
}
if(st->st_buffer_ptr + len >= st->st_buffer_size) {
st->st_buffer_size += len * 4;
st->st_buffer = realloc(st->st_buffer, st->st_buffer_size);
}
memcpy(st->st_buffer + st->st_buffer_ptr, data, len);
st->st_buffer_ptr += len;
if(st->st_parser_ptr == 0) {
int hlen;
if(st->st_buffer_ptr < 9)
return;
hlen = parse_pes_header(t, st, st->st_buffer + 6, st->st_buffer_ptr - 6);
if(hlen < 0)
return;
st->st_parser_ptr += 6 + hlen;
}
p = st->st_parser_ptr;
while((l = st->st_buffer_ptr - p) > 3) {
if(st->st_buffer[p] == 0x56 && (st->st_buffer[p + 1] & 0xe0) == 0xe0) {
muxlen = (st->st_buffer[p + 1] & 0x1f) << 8 |
st->st_buffer[p + 2];
if(l < muxlen + 3)
break;
parse_latm_audio_mux_element(t, st, st->st_buffer + p + 3, muxlen);
p += muxlen + 3;
} else {
printf("skip\n");
p++;
}
}
st->st_parser_ptr = p;
}
/**
* Generic video parser
*

1
src/tvhead.h
View file

@ -274,6 +274,7 @@ typedef struct th_stream {
uint32_t st_startcode;
uint32_t st_startcode_offset;
int st_parser_state;
int st_parser_ptr;
void *st_priv; /* Parser private data */
struct th_pkt *st_curpkt;