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/*****************************************************************
* gmerlin-avdecoder - a general purpose multimedia decoding library
*
* Copyright (c) 2001 - 2024 Members of the Gmerlin project
* http://github.com/bplaum
*
* 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
* 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/>.
* *****************************************************************/
#include <stdlib.h>
#include <string.h>
#include <config.h>
#include <avdec_private.h>
#include <parser.h>
#include <mpa_header.h>
#define HEADER_BYTES 4
typedef struct
{
bgav_mpa_header_t first_header;
} mpa_priv_t;
#if 0
static int parse_mpa(bgav_audio_parser_t * parser)
{
int i;
bgav_mpa_header_t h;
for(i = 0; i < parser->buf.len - HEADER_BYTES; i++)
{
if(bgav_mpa_header_decode(&h, parser->buf.buf + i))
{
if(parser->have_format)
{
gavl_audio_format_t fmt;
memset(&fmt, 0, sizeof(fmt));
bgav_mpa_header_get_format(&h, &fmt);
/* Sometimes we have bogus sync codes, which mess up the decoder */
if((fmt.samplerate != parser->s->data.audio.format->samplerate) ||
(fmt.num_channels != parser->s->data.audio.format->num_channels))
continue;
}
else
{
bgav_mpa_header_get_format(&h, parser->s->data.audio.format);
parser->have_format = 1;
if(parser->s->fourcc == BGAV_MK_FOURCC('m', 'p', 'g', 'a'))
{
switch(h.layer)
{
case 1:
parser->s->fourcc = BGAV_MK_FOURCC('.','m','p','1');
break;
case 2:
parser->s->fourcc = BGAV_MK_FOURCC('.','m','p','2');
break;
case 3:
parser->s->fourcc = BGAV_MK_FOURCC('.','m','p','3');
break;
}
}
if(!parser->s->container_bitrate)
parser->s->container_bitrate = h.bitrate;
return PARSER_HAVE_FORMAT;
}
bgav_audio_parser_set_frame(parser,
i, h.frame_bytes, h.samples_per_frame);
return PARSER_HAVE_FRAME;
}
}
return PARSER_NEED_DATA;
}
#endif
static int scan_header(bgav_packet_parser_t * parser, bgav_mpa_header_t * h)
{
int i;
for(i = parser->buf.pos; i < parser->buf.len - 4; i++)
{
if(bgav_mpa_header_decode(h, parser->buf.buf + i))
{
parser->buf.pos = i;
return 1;
}
}
return 0;
}
static int find_frame_boundary_mpa(bgav_packet_parser_t * parser, int * skip)
{
bgav_mpa_header_t h;
mpa_priv_t * priv = parser->priv;
if(parser->buf.pos + 4 >= parser->buf.len)
return 0; // Too little data
/* Not synchronized yet */
if(!priv->first_header.samples_per_frame)
{
if(scan_header(parser, &priv->first_header))
{
*skip = priv->first_header.frame_bytes;
return 1;
}
else
return 0;
}
while(scan_header(parser, &h))
{
if(bgav_mpa_header_equal(&h, &priv->first_header))
{
*skip = h.frame_bytes;
return 1;
}
else
{
/* Misdetected start code, try again */
parser->buf.pos += 4;
}
}
return 0;
}
static int parse_frame_mpa(bgav_packet_parser_t * parser, bgav_packet_t * pkt)
{
mpa_priv_t * priv = parser->priv;
if(!(parser->parser_flags & PARSER_HAS_HEADER))
bgav_mpa_header_get_format(&priv->first_header, parser->afmt);
pkt->duration = priv->first_header.samples_per_frame;
return 1;
}
static void cleanup_mpa(bgav_packet_parser_t * parser)
{
free(parser->priv);
}
#if 0
void reset_mpa(bgav_audio_parser_t * parser)
{
}
#endif
void bgav_packet_parser_init_mpeg(bgav_packet_parser_t * parser)
{
mpa_priv_t * priv;
priv = calloc(1, sizeof(*priv));
parser->priv = priv;
parser->cleanup = cleanup_mpa;
parser->find_frame_boundary = find_frame_boundary_mpa;
parser->parse_frame = parse_frame_mpa;
}
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