mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-13 18:55:08 +00:00
298 lines
7.6 KiB
C
298 lines
7.6 KiB
C
/*
|
|
* WAV encoder and decoder
|
|
* Copyright (c) 2001 Gerard Lantau.
|
|
*
|
|
* 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, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*/
|
|
#include "avformat.h"
|
|
#include "avi.h"
|
|
|
|
CodecTag codec_wav_tags[] = {
|
|
{ CODEC_ID_MP2, 0x50 },
|
|
{ CODEC_ID_MP3LAME, 0x55 },
|
|
{ CODEC_ID_AC3, 0x2000 },
|
|
{ CODEC_ID_PCM_S16LE, 0x01 },
|
|
{ CODEC_ID_PCM_U8, 0x01 }, /* must come after s16le in this list */
|
|
{ CODEC_ID_PCM_ALAW, 0x06 },
|
|
{ CODEC_ID_PCM_MULAW, 0x07 },
|
|
{ 0, 0 },
|
|
};
|
|
|
|
/* WAVEFORMATEX header */
|
|
/* returns the size or -1 on error */
|
|
int put_wav_header(ByteIOContext *pb, AVCodecContext *enc)
|
|
{
|
|
int tag, bps, blkalign, bytespersec;
|
|
int hdrsize = 18;
|
|
|
|
tag = codec_get_tag(codec_wav_tags, enc->codec_id);
|
|
if (tag == 0)
|
|
return -1;
|
|
put_le16(pb, tag);
|
|
put_le16(pb, enc->channels);
|
|
put_le32(pb, enc->sample_rate);
|
|
if (enc->codec_id == CODEC_ID_PCM_U8 ||
|
|
enc->codec_id == CODEC_ID_PCM_ALAW ||
|
|
enc->codec_id == CODEC_ID_PCM_MULAW) {
|
|
bps = 8;
|
|
} else if (enc->codec_id == CODEC_ID_MP2 || enc->codec_id == CODEC_ID_MP3LAME) {
|
|
bps = 0;
|
|
} else {
|
|
bps = 16;
|
|
}
|
|
|
|
if (enc->codec_id == CODEC_ID_MP2 || enc->codec_id == CODEC_ID_MP3LAME) {
|
|
blkalign = 1;
|
|
//blkalign = 144 * enc->bit_rate/enc->sample_rate;
|
|
} else
|
|
blkalign = enc->channels*bps >> 3;
|
|
if (enc->codec_id == CODEC_ID_PCM_U8 ||
|
|
enc->codec_id == CODEC_ID_PCM_S16LE) {
|
|
bytespersec = enc->sample_rate * blkalign;
|
|
} else {
|
|
bytespersec = enc->bit_rate / 8;
|
|
}
|
|
put_le32(pb, bytespersec); /* bytes per second */
|
|
put_le16(pb, blkalign); /* block align */
|
|
put_le16(pb, bps); /* bits per sample */
|
|
if (enc->codec_id == CODEC_ID_MP3LAME) {
|
|
put_le16(pb, 12); /* wav_extra_size */
|
|
hdrsize += 12;
|
|
put_le16(pb, 1); /* wID */
|
|
put_le32(pb, 2); /* fdwFlags */
|
|
put_le16(pb, 1152); /* nBlockSize */
|
|
put_le16(pb, 1); /* nFramesPerBlock */
|
|
put_le16(pb, 1393); /* nCodecDelay */
|
|
} else if (enc->codec_id == CODEC_ID_MP2) {
|
|
put_le16(pb, 22); /* wav_extra_size */
|
|
hdrsize += 22;
|
|
put_le16(pb, 2); /* fwHeadLayer */
|
|
put_le32(pb, enc->bit_rate); /* dwHeadBitrate */
|
|
put_le16(pb, enc->channels == 2 ? 1 : 8); /* fwHeadMode */
|
|
put_le16(pb, 0); /* fwHeadModeExt */
|
|
put_le16(pb, 1); /* wHeadEmphasis */
|
|
put_le16(pb, 16); /* fwHeadFlags */
|
|
put_le32(pb, 0); /* dwPTSLow */
|
|
put_le32(pb, 0); /* dwPTSHigh */
|
|
} else
|
|
put_le16(pb, 0); /* wav_extra_size */
|
|
|
|
return hdrsize;
|
|
}
|
|
|
|
int wav_codec_get_id(unsigned int tag, int bps)
|
|
{
|
|
int id;
|
|
id = codec_get_id(codec_wav_tags, tag);
|
|
if (id <= 0)
|
|
return id;
|
|
/* handle specific u8 codec */
|
|
if (id == CODEC_ID_PCM_S16LE && bps == 8)
|
|
id = CODEC_ID_PCM_U8;
|
|
return id;
|
|
}
|
|
|
|
typedef struct {
|
|
offset_t data;
|
|
} WAVContext;
|
|
|
|
static int wav_write_header(AVFormatContext *s)
|
|
{
|
|
WAVContext *wav;
|
|
ByteIOContext *pb = &s->pb;
|
|
offset_t fmt;
|
|
|
|
wav = malloc(sizeof(WAVContext));
|
|
if (!wav)
|
|
return -1;
|
|
memset(wav, 0, sizeof(WAVContext));
|
|
s->priv_data = wav;
|
|
|
|
put_tag(pb, "RIFF");
|
|
put_le32(pb, 0); /* file length */
|
|
put_tag(pb, "WAVE");
|
|
|
|
/* format header */
|
|
fmt = start_tag(pb, "fmt ");
|
|
if (put_wav_header(pb, &s->streams[0]->codec) < 0) {
|
|
free(wav);
|
|
return -1;
|
|
}
|
|
end_tag(pb, fmt);
|
|
|
|
/* data header */
|
|
wav->data = start_tag(pb, "data");
|
|
|
|
put_flush_packet(pb);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int wav_write_packet(AVFormatContext *s, int stream_index_ptr,
|
|
UINT8 *buf, int size, int force_pts)
|
|
{
|
|
ByteIOContext *pb = &s->pb;
|
|
put_buffer(pb, buf, size);
|
|
return 0;
|
|
}
|
|
|
|
static int wav_write_trailer(AVFormatContext *s)
|
|
{
|
|
ByteIOContext *pb = &s->pb;
|
|
WAVContext *wav = s->priv_data;
|
|
offset_t file_size;
|
|
|
|
if (!url_is_streamed(&s->pb)) {
|
|
end_tag(pb, wav->data);
|
|
|
|
/* update file size */
|
|
file_size = url_ftell(pb);
|
|
url_fseek(pb, 4, SEEK_SET);
|
|
put_le32(pb, (UINT32)(file_size - 8));
|
|
url_fseek(pb, file_size, SEEK_SET);
|
|
|
|
put_flush_packet(pb);
|
|
}
|
|
|
|
free(wav);
|
|
return 0;
|
|
}
|
|
|
|
/* return the size of the found tag */
|
|
/* XXX: > 2GB ? */
|
|
static int find_tag(ByteIOContext *pb, UINT32 tag1)
|
|
{
|
|
unsigned int tag;
|
|
int size;
|
|
|
|
for(;;) {
|
|
if (url_feof(pb))
|
|
return -1;
|
|
tag = get_le32(pb);
|
|
size = get_le32(pb);
|
|
if (tag == tag1)
|
|
break;
|
|
url_fseek(pb, size, SEEK_CUR);
|
|
}
|
|
if (size < 0)
|
|
size = 0x7fffffff;
|
|
return size;
|
|
}
|
|
|
|
/* wav input */
|
|
static int wav_read_header(AVFormatContext *s,
|
|
AVFormatParameters *ap)
|
|
{
|
|
int size;
|
|
unsigned int tag;
|
|
ByteIOContext *pb = &s->pb;
|
|
unsigned int id, channels, rate, bit_rate, extra_size, bps;
|
|
AVStream *st;
|
|
|
|
/* check RIFF header */
|
|
tag = get_le32(pb);
|
|
|
|
if (tag != MKTAG('R', 'I', 'F', 'F'))
|
|
return -1;
|
|
get_le32(pb); /* file size */
|
|
tag = get_le32(pb);
|
|
if (tag != MKTAG('W', 'A', 'V', 'E'))
|
|
return -1;
|
|
|
|
/* parse fmt header */
|
|
size = find_tag(pb, MKTAG('f', 'm', 't', ' '));
|
|
if (size < 0)
|
|
return -1;
|
|
id = get_le16(pb);
|
|
channels = get_le16(pb);
|
|
rate = get_le32(pb);
|
|
bit_rate = get_le32(pb) * 8;
|
|
get_le16(pb); /* block align */
|
|
bps = get_le16(pb); /* bits per sample */
|
|
if (size >= 18) {
|
|
/* wav_extra_size */
|
|
extra_size = get_le16(pb);
|
|
/* skip unused data */
|
|
url_fseek(pb, size - 18, SEEK_CUR);
|
|
}
|
|
|
|
size = find_tag(pb, MKTAG('d', 'a', 't', 'a'));
|
|
if (size < 0)
|
|
return -1;
|
|
|
|
/* now we are ready: build format streams */
|
|
st = malloc(sizeof(AVStream));
|
|
if (!st)
|
|
return -1;
|
|
s->nb_streams = 1;
|
|
s->streams[0] = st;
|
|
|
|
st->id = 0;
|
|
|
|
st->codec.codec_type = CODEC_TYPE_AUDIO;
|
|
st->codec.codec_tag = id;
|
|
st->codec.codec_id = wav_codec_get_id(id, bps);
|
|
st->codec.channels = channels;
|
|
st->codec.sample_rate = rate;
|
|
return 0;
|
|
}
|
|
|
|
#define MAX_SIZE 4096
|
|
|
|
static int wav_read_packet(AVFormatContext *s,
|
|
AVPacket *pkt)
|
|
{
|
|
int packet_size, n, ret;
|
|
|
|
if (url_feof(&s->pb))
|
|
return -EIO;
|
|
packet_size = url_get_packet_size(&s->pb);
|
|
n = MAX_SIZE / packet_size;
|
|
if (n <= 0)
|
|
return n = 1;
|
|
if (av_new_packet(pkt, n * packet_size))
|
|
return -EIO;
|
|
pkt->stream_index = 0;
|
|
|
|
ret = get_buffer(&s->pb, pkt->data, pkt->size);
|
|
if (ret < 0)
|
|
av_free_packet(pkt);
|
|
/* note: we need to modify the packet size here to handle the last
|
|
packet */
|
|
pkt->size = ret;
|
|
return ret;
|
|
}
|
|
|
|
static int wav_read_close(AVFormatContext *s)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
AVFormat wav_format = {
|
|
"wav",
|
|
"wav format",
|
|
"audio/x-wav",
|
|
"wav",
|
|
CODEC_ID_PCM_S16LE,
|
|
CODEC_ID_NONE,
|
|
wav_write_header,
|
|
wav_write_packet,
|
|
wav_write_trailer,
|
|
|
|
wav_read_header,
|
|
wav_read_packet,
|
|
wav_read_close,
|
|
};
|