/* the Music Player Daemon (MPD)
* (c)2003-2004 by Warren Dukes (shank@mercury.chem.pitt.edu)
* This project's homepage is: http://www.musicpd.org
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "mp3_decode.h"
#ifdef HAVE_MAD
#include "pcm_utils.h"
#ifdef USE_MPD_MAD
#include "libmad/mad.h"
#else
#include <mad.h>
#endif
#ifdef HAVE_ID3TAG
#ifdef USE_MPD_ID3TAG
#include "libid3tag/id3tag.h"
#else
#include <id3tag.h>
#endif
#endif
#include "playerData.h"
#include "log.h"
#include "utils.h"
#include "inputStream.h"
#include "outputBuffer.h"
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#define FRAMES_CUSHION 2000
#define READ_BUFFER_SIZE 40960
#define DECODE_SKIP -3
#define DECODE_BREAK -2
#define DECODE_CONT -1
#define DECODE_OK 0
/* this is stolen from mpg321! */
struct audio_dither {
mad_fixed_t error[3];
mad_fixed_t random;
};
unsigned long prng(unsigned long state) {
return (state * 0x0019660dL + 0x3c6ef35fL) & 0xffffffffL;
}
signed long audio_linear_dither(unsigned int bits, mad_fixed_t sample, struct audio_dither *dither) {
unsigned int scalebits;
mad_fixed_t output, mask, random;
enum {
MIN = -MAD_F_ONE,
MAX = MAD_F_ONE - 1
};
sample += dither->error[0] - dither->error[1] + dither->error[2];
dither->error[2] = dither->error[1];
dither->error[1] = dither->error[0] / 2;
output = sample + (1L << (MAD_F_FRACBITS + 1 - bits - 1));
scalebits = MAD_F_FRACBITS + 1 - bits;
mask = (1L << scalebits) - 1;
random = prng(dither->random);
output += (random & mask) - (dither->random & mask);
dither->random = random;
if (output > MAX) {
output = MAX;
if (sample > MAX)
sample = MAX;
}
else if (output < MIN) {
output = MIN;
if (sample < MIN)
sample = MIN;
}
output &= ~mask;
dither->error[0] = sample - output;
return output >> scalebits;
}
/* end of stolen stuff from mpg321 */
/* decoder stuff is based on madlld */
#define MP3_DATA_OUTPUT_BUFFER_SIZE 4096
typedef struct _mp3DecodeData {
struct mad_stream stream;
struct mad_frame frame;
struct mad_synth synth;
mad_timer_t timer;
unsigned char readBuffer[READ_BUFFER_SIZE];
char outputBuffer[MP3_DATA_OUTPUT_BUFFER_SIZE];
char * outputPtr;
char * outputBufferEnd;
float totalTime;
float elapsedTime;
int muteFrame;
long * frameOffset;
mad_timer_t * times;
long highestFrame;
long maxFrames;
long currentFrame;
int flush;
unsigned long bitRate;
InputStream inStream;
} mp3DecodeData;
int initMp3DecodeData(mp3DecodeData * data, char * file) {
int ret;
while(((ret = openInputStream(&(data->inStream),file))<0)) /*&&
data->inStream.error==EINTR);*/
if(ret<0) return -1;
data->outputPtr = data->outputBuffer;
data->outputBufferEnd = data->outputBuffer+MP3_DATA_OUTPUT_BUFFER_SIZE;
data->muteFrame = 0;
data->highestFrame = 0;
data->maxFrames = 0;
data->frameOffset = NULL;
data->times = NULL;
data->currentFrame = 0;
data->flush = 1;
mad_stream_init(&data->stream);
data->stream.options |= MAD_OPTION_IGNORECRC;
mad_frame_init(&data->frame);
mad_synth_init(&data->synth);
mad_timer_reset(&data->timer);
return 0;
}
int fillMp3InputBuffer(mp3DecodeData * data, long offset) {
size_t readSize;
size_t remaining;
unsigned char * readStart;
if(offset>=0) {
seekInputStream(&(data->inStream),offset,SEEK_SET);
}
if(offset==-1 && (data->stream).next_frame!=NULL) {
remaining = (data->stream).bufend-(data->stream).next_frame;
memmove(data->readBuffer,(data->stream).next_frame,remaining);
readStart = (data->readBuffer)+remaining;
readSize = READ_BUFFER_SIZE-remaining;
}
else {
readSize = READ_BUFFER_SIZE;
readStart = data->readBuffer,
remaining = 0;
}
readSize = readFromInputStream(&(data->inStream),readStart,1,readSize);
if(readSize<=0) return -1;
mad_stream_buffer(&data->stream,data->readBuffer,readSize+remaining);
(data->stream).error = 0;
return 0;
}
int decodeNextFrameHeader(mp3DecodeData * data) {
if((data->stream).buffer==NULL || (data->stream).error==MAD_ERROR_BUFLEN) {
if(fillMp3InputBuffer(data,/*data->currentOffset*/-1) < 0) {
return DECODE_BREAK;
}
}
if(mad_header_decode(&data->frame.header,&data->stream)) {
#ifdef HAVE_ID3TAG
if((data->stream).error==MAD_ERROR_LOSTSYNC &&
(data->stream).this_frame)
{
signed long tagsize = id3_tag_query(
(data->stream).this_frame,
(data->stream).bufend-
(data->stream).this_frame);
if(tagsize>0) {
mad_stream_skip(&(data->stream),tagsize);
return DECODE_CONT;
}
}
#endif
if(MAD_RECOVERABLE((data->stream).error)) return DECODE_SKIP;
else {
if((data->stream).error==MAD_ERROR_BUFLEN) return DECODE_CONT;
else
{
ERROR("unrecoverable frame level error "
"(%s).\n",
mad_stream_errorstr(&data->stream));
data->flush = 0;
return DECODE_BREAK;
}
}
}
return DECODE_OK;
}
int decodeNextFrame(mp3DecodeData * data) {
if((data->stream).buffer==NULL || (data->stream).error==MAD_ERROR_BUFLEN) {
if(fillMp3InputBuffer(data,/*data->currentOffset*/-1) < 0) {
return DECODE_BREAK;
}
}
if(mad_frame_decode(&data->frame,&data->stream)) {
#ifdef HAVE_ID3TAG
if((data->stream).error==MAD_ERROR_LOSTSYNC) {
signed long tagsize = id3_tag_query(
(data->stream).this_frame,
(data->stream).bufend-
(data->stream).this_frame);
if(tagsize>0) {
mad_stream_skip(&(data->stream),tagsize);
return DECODE_CONT;
}
}
#endif
if(MAD_RECOVERABLE((data->stream).error)) return DECODE_SKIP;
else {
if((data->stream).error==MAD_ERROR_BUFLEN) return DECODE_CONT;
else
{
ERROR("unrecoverable frame level error "
"(%s).\n",
mad_stream_errorstr(&data->stream));
data->flush = 0;
return DECODE_BREAK;
}
}
}
return DECODE_OK;
}
/* xing stuff stolen from alsaplayer */
# define XING_MAGIC (('X' << 24) | ('i' << 16) | ('n' << 8) | 'g')
struct xing {
long flags; /* valid fields (see below) */
unsigned long frames; /* total number of frames */
unsigned long bytes; /* total number of bytes */
unsigned char toc[100]; /* 100-point seek table */
long scale; /* ?? */
};
enum {
XING_FRAMES = 0x00000001L,
XING_BYTES = 0x00000002L,
XING_TOC = 0x00000004L,
XING_SCALE = 0x00000008L
};
int parse_xing(struct xing *xing, struct mad_bitptr ptr, unsigned int bitlen)
{
if (bitlen < 64 || mad_bit_read(&ptr, 32) != XING_MAGIC) goto fail;
xing->flags = mad_bit_read(&ptr, 32);
bitlen -= 64;
if (xing->flags & XING_FRAMES) {
if (bitlen < 32) goto fail;
xing->frames = mad_bit_read(&ptr, 32);
bitlen -= 32;
}
if (xing->flags & XING_BYTES) {
if (bitlen < 32) goto fail;
xing->bytes = mad_bit_read(&ptr, 32);
bitlen -= 32;
}
if (xing->flags & XING_TOC) {
int i;
if (bitlen < 800) goto fail;
for (i = 0; i < 100; ++i) xing->toc[i] = mad_bit_read(&ptr, 8);
bitlen -= 800;
}
if (xing->flags & XING_SCALE) {
if (bitlen < 32) goto fail;
xing->scale = mad_bit_read(&ptr, 32);
bitlen -= 32;
}
return 1;
fail:
xing->flags = 0;
return 0;
}
int decodeFirstFrame(mp3DecodeData * data) {
struct xing xing;
int ret;
int skip;
memset(&xing,0,sizeof(struct xing));
xing.flags = 0;
while(1) {
skip = 0;
while((ret = decodeNextFrameHeader(data))==DECODE_CONT);
if(ret==DECODE_SKIP) skip = 1;
else if(ret==DECODE_BREAK) return -1;
while((ret = decodeNextFrame(data))==DECODE_CONT);
if(ret==DECODE_BREAK) return -1;
if(!skip && ret==DECODE_OK) break;
}
if(parse_xing(&xing,data->stream.anc_ptr,data->stream.anc_bitlen)) {
if(xing.flags & XING_FRAMES) {
mad_timer_t duration = data->frame.header.duration;
mad_timer_multiply(&duration,xing.frames);
data->muteFrame = 1;
data->totalTime = ((float)mad_timer_count(duration,
MAD_UNITS_MILLISECONDS))/1000;
data->maxFrames = xing.frames;
}
}
else {
size_t offset = data->inStream.offset;
mad_timer_t duration = data->frame.header.duration;
float frameTime = ((float)mad_timer_count(duration,
MAD_UNITS_MILLISECONDS))/1000;
if(data->stream.this_frame!=NULL) {
offset-= data->stream.bufend-data->stream.this_frame;
}
else {
offset-= data->stream.bufend-data->stream.buffer;
}
data->totalTime = ((data->inStream.size-offset)*8.0)/
(data->frame).header.bitrate;
data->maxFrames = data->totalTime/frameTime+FRAMES_CUSHION;
}
data->frameOffset = malloc(sizeof(long)*data->maxFrames);
data->times = malloc(sizeof(mad_timer_t)*data->maxFrames);
return 0;
}
void mp3DecodeDataFinalize(mp3DecodeData * data) {
mad_synth_finish(&data->synth);
mad_frame_finish(&data->frame);
mad_stream_finish(&data->stream);
while(closeInputStream(&(data->inStream))<0 &&
data->inStream.error==EINTR);
if(data->frameOffset) free(data->frameOffset);
if(data->times) free(data->times);
}
/* this is primarily used for getting total time for tags */
int getMp3TotalTime(char * file) {
mp3DecodeData data;
int ret;
if(initMp3DecodeData(&data,file)<0) return -1;
if(decodeFirstFrame(&data)<0) ret = -1;
else ret = data.totalTime+0.5;
mp3DecodeDataFinalize(&data);
return ret;
}
int openMp3(char * file, mp3DecodeData * data) {
if(initMp3DecodeData(data,file) < 0) {
ERROR("problems opening \"%s\"\n",file);
return -1;
}
if(decodeFirstFrame(data)<0) {
mp3DecodeDataFinalize(data);
return -1;
}
return 0;
}
int mp3Read(mp3DecodeData * data, OutputBuffer * cb, DecoderControl * dc) {
static int i;
static int ret;
static struct audio_dither dither;
static int skip;
if(data->currentFrame>=data->highestFrame &&
data->highestFrame<data->maxFrames)
{
mad_timer_add(&data->timer,(data->frame).header.duration);
data->bitRate = (data->frame).header.bitrate;
data->frameOffset[data->currentFrame] = data->inStream.offset;
if(data->stream.this_frame!=NULL) {
data->frameOffset[data->currentFrame]-=
data->stream.bufend-
data->stream.this_frame;
}
else {
data->frameOffset[data->currentFrame]-=
data->stream.bufend-data->stream.buffer;
}
data->times[data->currentFrame] = data->timer;
data->highestFrame++;
}
else data->timer = data->times[data->currentFrame];
data->currentFrame++;
data->elapsedTime = ((float)mad_timer_count(data->timer,MAD_UNITS_MILLISECONDS))/1000;
if(data->muteFrame) {
if(!dc->seek) data->muteFrame = 0;
else if(dc->seekWhere<=data->elapsedTime) {
data->muteFrame = 0;
dc->seek = 0;
}
}
else {
long ret;
mad_synth_frame(&data->synth,&data->frame);
for(i=0;i<(data->synth).pcm.length;i++) {
mpd_sint16 * sample;
sample = (mpd_sint16 *)data->outputPtr;
*sample = (mpd_sint16) audio_linear_dither(16,
(data->synth).pcm.samples[0][i],
&dither);
data->outputPtr+=2;
if(MAD_NCHANNELS(&(data->frame).header)==2) {
sample = (mpd_sint16 *)data->outputPtr;
*sample = (mpd_sint16) audio_linear_dither(16,
(data->synth).pcm.samples[1][i],
&dither);
data->outputPtr+=2;
}
if(data->outputPtr==data->outputBufferEnd) {
ret = sendDataToOutputBuffer(cb,dc,
data->outputBuffer,
MP3_DATA_OUTPUT_BUFFER_SIZE,
data->elapsedTime,
data->bitRate/1000);
if(ret == OUTPUT_BUFFER_DC_STOP) {
return DECODE_BREAK;
}
data->outputPtr = data->outputBuffer;
if(ret == OUTPUT_BUFFER_DC_SEEK) break;
}
}
if(dc->seek) {
long i = 0;
cb->wrap = 0;
cb->end = cb->begin;
data->muteFrame = 1;
while(i<data->highestFrame && dc->seekWhere >
((float)mad_timer_count(data->times[i],
MAD_UNITS_MILLISECONDS))/1000)
{
i++;
}
if(i<data->highestFrame) {
data->currentFrame = i;
fillMp3InputBuffer(data,data->frameOffset[i]);
data->muteFrame = 0;
dc->seek = 0;
}
}
}
while(1) {
skip = 0;
while((ret = decodeNextFrameHeader(data))==DECODE_CONT);
if(ret==DECODE_SKIP) skip = 1;
else if(ret==DECODE_BREAK) break;
if(!data->muteFrame) {
while((ret = decodeNextFrame(data))==DECODE_CONT);
if(ret==DECODE_BREAK) break;
}
if(!skip && ret==DECODE_OK) break;
}
return ret;
}
void initAudioFormatFromMp3DecodeData(mp3DecodeData * data, AudioFormat * af) {
af->bits = 16;
af->sampleRate = (data->frame).header.samplerate;
af->channels = MAD_NCHANNELS(&(data->frame).header);
}
int mp3_decode(OutputBuffer * cb, DecoderControl * dc) {
mp3DecodeData data;
if(openMp3(dc->file,&data) < 0) {
ERROR("Input does not appear to be a mp3 bit stream.\n");
return -1;
}
initAudioFormatFromMp3DecodeData(&data, &(dc->audioFormat));
getOutputAudioFormat(&(dc->audioFormat), &(cb->audioFormat));
dc->totalTime = data.totalTime;
dc->start = 0;
dc->state = DECODE_STATE_DECODE;
while(mp3Read(&data,cb,dc)!=DECODE_BREAK);
/* send last little bit if not dc->stop */
if(data.outputPtr!=data.outputBuffer && data.flush) {
if(sendDataToOutputBuffer(cb,dc,data.outputBuffer,
data.outputPtr-data.outputBuffer,
data.elapsedTime,data.bitRate/1000) == 0)
{
flushOutputBuffer(cb);
}
}
mp3DecodeDataFinalize(&data);
if(dc->seek) dc->seek = 0;
if(dc->stop) {
dc->state = DECODE_STATE_STOP;
dc->stop = 0;
}
else dc->state = DECODE_STATE_STOP;
return 0;
}
#endif
/* vim:set shiftwidth=8 tabstop=8 expandtab: */