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ffmpeg/libavformat/mmf.c

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/*
* Yamaha SMAF format
* Copyright (c) 2005 Vidar Madsen
*
* This library 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 of the License, or (at your option) any later version.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include "avi.h"
typedef struct {
offset_t atrpos, atsqpos, awapos;
offset_t data_size;
} MMFContext;
static int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
static int mmf_rate_code(int rate)
{
int i;
for(i = 0; i < 5; i++)
if(mmf_rates[i] == rate)
return i;
return -1;
}
static int mmf_rate(int code)
{
if((code < 0) || (code > 4))
return -1;
return mmf_rates[code];
}
#ifdef CONFIG_MUXERS
/* Copy of end_tag() from avienc.c, but for big-endian chunk size */
static void end_tag_be(ByteIOContext *pb, offset_t start)
{
offset_t pos;
pos = url_ftell(pb);
url_fseek(pb, start - 4, SEEK_SET);
put_be32(pb, (uint32_t)(pos - start));
url_fseek(pb, pos, SEEK_SET);
}
static int mmf_write_header(AVFormatContext *s)
{
MMFContext *mmf = s->priv_data;
ByteIOContext *pb = &s->pb;
offset_t pos;
int rate;
rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
if(rate < 0) {
av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n", s->streams[0]->codec->sample_rate);
return -1;
}
put_tag(pb, "MMMD");
put_be32(pb, 0);
pos = start_tag(pb, "CNTI");
put_byte(pb, 0); /* class */
put_byte(pb, 0); /* type */
put_byte(pb, 0); /* code type */
put_byte(pb, 0); /* status */
put_byte(pb, 0); /* counts */
put_tag(pb, "VN:libavcodec,"); /* metadata ("ST:songtitle,VN:version,...") */
end_tag_be(pb, pos);
put_buffer(pb, "ATR\x00", 4);
put_be32(pb, 0);
mmf->atrpos = url_ftell(pb);
put_byte(pb, 0); /* format type */
put_byte(pb, 0); /* sequence type */
put_byte(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
put_byte(pb, 0); /* wave base bit */
put_byte(pb, 2); /* time base d */
put_byte(pb, 2); /* time base g */
put_tag(pb, "Atsq");
put_be32(pb, 16);
mmf->atsqpos = url_ftell(pb);
/* Will be filled on close */
put_buffer(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
mmf->awapos = start_tag(pb, "Awa\x01");
av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
put_flush_packet(pb);
return 0;
}
static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
{
ByteIOContext *pb = &s->pb;
put_buffer(pb, pkt->data, pkt->size);
return 0;
}
/* Write a variable-length symbol */
static void put_varlength(ByteIOContext *pb, int val)
{
if(val < 128)
put_byte(pb, val);
else {
val -= 128;
put_byte(pb, 0x80 | val >> 7);
put_byte(pb, 0x7f & val);
}
}
static int mmf_write_trailer(AVFormatContext *s)
{
ByteIOContext *pb = &s->pb;
MMFContext *mmf = s->priv_data;
offset_t pos, size;
int gatetime;
if (!url_is_streamed(&s->pb)) {
/* Fill in length fields */
end_tag_be(pb, mmf->awapos);
end_tag_be(pb, mmf->atrpos);
end_tag_be(pb, 8);
pos = url_ftell(pb);
size = pos - mmf->awapos;
/* Fill Atsq chunk */
url_fseek(pb, mmf->atsqpos, SEEK_SET);
/* "play wav" */
put_byte(pb, 0); /* start time */
put_byte(pb, 1); /* (channel << 6) | wavenum */
gatetime = size * 500 / s->streams[0]->codec->sample_rate;
put_varlength(pb, gatetime); /* duration */
/* "nop" */
put_varlength(pb, gatetime); /* start time */
put_buffer(pb, "\xff\x00", 2); /* nop */
/* "end of sequence" */
put_buffer(pb, "\x00\x00\x00\x00", 4);
url_fseek(pb, pos, SEEK_SET);
put_flush_packet(pb);
}
return 0;
}
#endif //CONFIG_MUXERS
static int mmf_probe(AVProbeData *p)
{
/* check file header */
if (p->buf_size <= 32)
return 0;
if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
p->buf[2] == 'M' && p->buf[3] == 'D' &&
p->buf[8] == 'C' && p->buf[9] == 'N' &&
p->buf[10] == 'T' && p->buf[11] == 'I')
return AVPROBE_SCORE_MAX;
else
return 0;
}
/* mmf input */
static int mmf_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
MMFContext *mmf = s->priv_data;
unsigned int tag;
ByteIOContext *pb = &s->pb;
AVStream *st;
offset_t file_size, size;
int rate, params;
tag = get_le32(pb);
if (tag != MKTAG('M', 'M', 'M', 'D'))
return -1;
file_size = get_be32(pb);
/* Skip some unused chunks that may or may not be present */
for(;; url_fseek(pb, size, SEEK_CUR)) {
tag = get_le32(pb);
size = get_be32(pb);
if(tag == MKTAG('C','N','T','I')) continue;
if(tag == MKTAG('O','P','D','A')) continue;
break;
}
/* Tag = "ATRx", where "x" = track number */
if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
return -1;
}
if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
return -1;
}
get_byte(pb); /* format type */
get_byte(pb); /* sequence type */
params = get_byte(pb); /* (channel << 7) | (format << 4) | rate */
rate = mmf_rate(params & 0x0f);
if(rate < 0) {
av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
return -1;
}
get_byte(pb); /* wave base bit */
get_byte(pb); /* time base d */
get_byte(pb); /* time base g */
/* Skip some unused chunks that may or may not be present */
for(;; url_fseek(pb, size, SEEK_CUR)) {
tag = get_le32(pb);
size = get_be32(pb);
if(tag == MKTAG('A','t','s','q')) continue;
if(tag == MKTAG('A','s','p','I')) continue;
break;
}
/* Make sure it's followed by an Awa chunk, aka wave data */
if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
return -1;
}
mmf->data_size = size;
st = av_new_stream(s, 0);
if (!st)
return AVERROR_NOMEM;
st->codec->codec_type = CODEC_TYPE_AUDIO;
st->codec->codec_id = CODEC_ID_ADPCM_YAMAHA;
st->codec->sample_rate = rate;
st->codec->channels = 1;
st->codec->bits_per_sample = 4;
st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_sample;
av_set_pts_info(st, 64, 1, st->codec->sample_rate);
return 0;
}
#define MAX_SIZE 4096
static int mmf_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
MMFContext *mmf = s->priv_data;
AVStream *st;
int ret, size;
if (url_feof(&s->pb))
return AVERROR_IO;
st = s->streams[0];
size = MAX_SIZE;
if(size > mmf->data_size)
size = mmf->data_size;
if(!size)
return AVERROR_IO;
if (av_new_packet(pkt, size))
return AVERROR_IO;
pkt->stream_index = 0;
ret = get_buffer(&s->pb, pkt->data, pkt->size);
if (ret < 0)
av_free_packet(pkt);
mmf->data_size -= ret;
pkt->size = ret;
return ret;
}
static int mmf_read_close(AVFormatContext *s)
{
return 0;
}
static int mmf_read_seek(AVFormatContext *s,
int stream_index, int64_t timestamp, int flags)
{
return pcm_read_seek(s, stream_index, timestamp, flags);
}
static AVInputFormat mmf_iformat = {
"mmf",
"mmf format",
sizeof(MMFContext),
mmf_probe,
mmf_read_header,
mmf_read_packet,
mmf_read_close,
mmf_read_seek,
};
#ifdef CONFIG_MUXERS
static AVOutputFormat mmf_oformat = {
"mmf",
"mmf format",
"application/vnd.smaf",
"mmf",
sizeof(MMFContext),
CODEC_ID_ADPCM_YAMAHA,
CODEC_ID_NONE,
mmf_write_header,
mmf_write_packet,
mmf_write_trailer,
};
#endif //CONFIG_MUXERS
int ff_mmf_init(void)
{
av_register_input_format(&mmf_iformat);
#ifdef CONFIG_MUXERS
av_register_output_format(&mmf_oformat);
#endif //CONFIG_MUXERS
return 0;
}
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