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author | Warren Dukes <warren.dukes@gmail.com> | 2004-02-23 23:41:20 +0000 |
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committer | Warren Dukes <warren.dukes@gmail.com> | 2004-02-23 23:41:20 +0000 |
commit | d35747a40c7dea12de95f78a4f283a45ef687597 (patch) | |
tree | 3a85f138e68c7ef3e5a9ece863ed7266ad1cd7ce /src/mp3_decode.c | |
download | mpd-d35747a40c7dea12de95f78a4f283a45ef687597.tar.gz mpd-d35747a40c7dea12de95f78a4f283a45ef687597.tar.xz mpd-d35747a40c7dea12de95f78a4f283a45ef687597.zip |
import from SF CVS
git-svn-id: https://svn.musicpd.org/mpd/trunk@1 09075e82-0dd4-0310-85a5-a0d7c8717e4f
Diffstat (limited to '')
-rw-r--r-- | src/mp3_decode.c | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/src/mp3_decode.c b/src/mp3_decode.c new file mode 100644 index 000000000..086e3be13 --- /dev/null +++ b/src/mp3_decode.c @@ -0,0 +1,512 @@ +/* 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 + */ + +#ifdef HAVE_MAD + +#include "mp3_decode.h" +#include "pcm_utils.h" +#ifdef USE_MPD_MAD +#include "libmad/mad.h" +#else +#include <mad.h> +#endif +#include "playerData.h" +#include "log.h" + +#include <stdio.h> +#include <string.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> + +#define FRAMES_CUSHION 2000 + +#define READ_BUFFER_SIZE 40960 + +#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 */ + +typedef struct _mp3DecodeData { + FILE * fp; + struct mad_stream stream; + struct mad_frame frame; + struct mad_synth synth; + mad_timer_t timer; + unsigned char readBuffer[READ_BUFFER_SIZE]; + char outputBuffer[CHUNK_SIZE]; + char * outputPtr; + char * outputBufferEnd; + float totalTime; + float elapsedTime; + int muteFrame; + long * frameOffset; + mad_timer_t * times; + long highestFrame; + long currentOffset; + long maxFrames; + long currentFrame; + int flush; + unsigned long bitRate; +} mp3DecodeData; + +void initMp3DecodeData(mp3DecodeData * data) { + data->outputPtr = data->outputBuffer; + data->outputBufferEnd = data->outputBuffer+CHUNK_SIZE; + data->muteFrame = 0; + data->currentOffset = 0; + data->highestFrame = 0; + data->maxFrames = 0; + data->frameOffset = NULL; + data->times = NULL; + data->currentFrame = 0; + data->flush = 1; + mad_stream_init(&data->stream); + mad_frame_init(&data->frame); + mad_synth_init(&data->synth); + mad_timer_reset(&data->timer); +} + +int fillMp3InputBuffer(mp3DecodeData * data, long offset) { + size_t readSize; + size_t remaining; + unsigned char * readStart; + + if(offset>=0) { + if(fseek(data->fp,offset,SEEK_SET)==0) { + data->currentOffset = offset; + } + } + + 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 = fread(readStart,1,readSize,data->fp); + if(readSize<=0) return -1; + + data->currentOffset+=readSize; + + 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)) { + if(MAD_RECOVERABLE((data->stream).error)) return DECODE_CONT; + 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)) { + if(MAD_RECOVERABLE((data->stream).error)) return DECODE_CONT; + 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 stat filestat; + struct xing xing; + int ret; + + memset(&xing,0,sizeof(struct xing)); + xing.flags = 0; + + while((ret = decodeNextFrameHeader(data))==DECODE_CONT); + if(ret!=DECODE_OK) return -1; + while((ret = decodeNextFrame(data))==DECODE_CONT); + if(ret!=DECODE_OK) return -1; + + 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 { + mad_timer_t duration = data->frame.header.duration; + float frameTime = ((float)mad_timer_count(duration, + MAD_UNITS_MILLISECONDS))/1000; + fstat(fileno(data->fp),&filestat); + data->totalTime = (filestat.st_size*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); + + if(data->fp) fclose(data->fp); + 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; + + while(!(data.fp = fopen(file,"r")) && errno==EINTR); + if(!data.fp) return -1; + + initMp3DecodeData(&data); + if(decodeFirstFrame(&data)<0) ret = -1; + else ret = data.totalTime; + mp3DecodeDataFinalize(&data); + + return ret; +} + +int openMp3(char * file, mp3DecodeData * data) { + if((data->fp = fopen(file,"r"))<=0) { + ERROR("problems opening \"%s\"\n",file); + return -1; + } + initMp3DecodeData(data); + if(decodeFirstFrame(data)<0) { + mp3DecodeDataFinalize(data); + return -1; + } + + return 0; +} + +int mp3ChildSendData(mp3DecodeData * data, Buffer * cb, DecoderControl * dc) { + while(cb->begin==cb->end && cb->wrap && !dc->stop && !dc->seek) + usleep(1000); + if(dc->stop) return -1; + /* just for now, so it doesn't hang */ + if(dc->seek) return 0; + /* be sure to remove this! */ + +#ifdef WORDS_BIGENDIAN + pcm_changeBufferEndianness(data->outputBuffer,CHUNK_SIZE,16); +#endif + memcpy(cb->chunks+cb->end*CHUNK_SIZE,data->outputBuffer,CHUNK_SIZE); + cb->chunkSize[cb->end] = data->outputPtr-data->outputBuffer; + cb->bitRate[cb->end] = data->bitRate/1000; + cb->times[cb->end] = data->elapsedTime; + + cb->end++; + if(cb->end>=BUFFERED_CHUNKS) { + cb->end = 0; + cb->wrap = 1; + } + + return 0; +} + +int mp3Read(mp3DecodeData * data, Buffer * cb, DecoderControl * dc) { + static int i; + static int ret; + static struct audio_dither dither; + + 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->currentOffset; + if(data->stream.this_frame!=NULL) { + data->frameOffset[data->currentFrame]+= + data->stream.this_frame- + data->stream.buffer; + } + 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 { + mad_synth_frame(&data->synth,&data->frame); + + for(i=0;i<(data->synth).pcm.length;i++) { + signed int sample; + + sample = (signed int) audio_linear_dither(16,(data->synth).pcm.samples[0][i],&dither); + *(data->outputPtr++) = sample&0xff; + *(data->outputPtr++) = sample>>8; + + if(MAD_NCHANNELS(&(data->frame).header)==2) { + sample = (signed int) audio_linear_dither(16,(data->synth).pcm.samples[1][i],&dither); + *(data->outputPtr++) = sample&0xff; + *(data->outputPtr++) = sample>>8; + } + + if(data->outputPtr==data->outputBufferEnd) { + if(mp3ChildSendData(data,cb,dc)<0) { + data->flush = 0; + return DECODE_BREAK; + } + data->outputPtr = data->outputBuffer; + if(dc->seek) break; + } + } + + if(dc->seek) { + long i = 0; + cb->wrap = 0; + cb->end = 0; + 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; + } + } + } + + if(data->muteFrame) { + while((ret=decodeNextFrameHeader(data))==DECODE_CONT); + } + else while((ret=decodeNextFrame(data))==DECODE_CONT); + + 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(Buffer * cb, AudioFormat * af, 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,af); + cb->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) { + mp3ChildSendData(&data,cb,dc); + } + + 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 |