rockbox/firmware/mp3data.c
Linus Nielsen Feltzing 2c07e78efc Don't accidentally add Xing headers to CBR files
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@3419 a1c6a512-1295-4272-9138-f99709370657
2003-03-10 18:25:40 +00:00

698 lines
19 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Daniel Stenberg
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
/*
* Parts of this code has been stolen from the Ample project and was written
* by David Härdeman. It has since been extended and enhanced pretty much by
* all sorts of friendly Rockbox people.
*
* A nice reference for MPEG header info:
* http://rockbox.haxx.se/docs/mpeghdr.html
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include "debug.h"
#include "mp3data.h"
#include "file.h"
#define DEBUG_VERBOSE
#define BYTES2INT(b1,b2,b3,b4) (((b1 & 0xFF) << (3*8)) | \
((b2 & 0xFF) << (2*8)) | \
((b3 & 0xFF) << (1*8)) | \
((b4 & 0xFF) << (0*8)))
#define SYNC_MASK (0x7ff << 21)
#define VERSION_MASK (3 << 19)
#define LAYER_MASK (3 << 17)
#define PROTECTION_MASK (1 << 16)
#define BITRATE_MASK (0xf << 12)
#define SAMPLERATE_MASK (3 << 10)
#define PADDING_MASK (1 << 9)
#define PRIVATE_MASK (1 << 8)
#define CHANNELMODE_MASK (3 << 6)
#define MODE_EXT_MASK (3 << 4)
#define COPYRIGHT_MASK (1 << 3)
#define ORIGINAL_MASK (1 << 2)
#define EMPHASIS_MASK 3
/* Table of bitrates for MP3 files, all values in kilo.
* Indexed by version, layer and value of bit 15-12 in header.
*/
const int bitrate_table[2][3][16] =
{
{
{0,32,64,96,128,160,192,224,256,288,320,352,384,416,448,0},
{0,32,48,56, 64,80, 96, 112,128,160,192,224,256,320,384,0},
{0,32,40,48, 56,64, 80, 96, 112,128,160,192,224,256,320,0}
},
{
{0,32,48,56,64,80,96,112,128,144,160,176,192,224,256,0},
{0, 8,16,24,32,40,48, 56, 64, 80, 96,112,128,144,160,0},
{0, 8,16,24,32,40,48, 56, 64, 80, 96,112,128,144,160,0}
}
};
/* Table of samples per frame for MP3 files.
* Indexed by layer. Multiplied with 1000.
*/
const int bs[3] = {384000, 1152000, 1152000};
/* Table of sample frequency for MP3 files.
* Indexed by version and layer.
*/
const int freqtab[][4] =
{
{11025, 12000, 8000, 0}, /* MPEG version 2.5 */
{44100, 48000, 32000, 0}, /* MPEG Version 1 */
{22050, 24000, 16000, 0}, /* MPEG version 2 */
};
/* check if 'head' is a valid mp3 frame header */
static bool is_mp3frameheader(unsigned long head)
{
if ((head & SYNC_MASK) != (unsigned long)SYNC_MASK) /* bad sync? */
return false;
if ((head & VERSION_MASK) == (1 << 19)) /* bad version? */
return false;
if (!(head & LAYER_MASK)) /* no layer? */
return false;
if ((head & BITRATE_MASK) == BITRATE_MASK) /* bad bitrate? */
return false;
if (!(head & BITRATE_MASK)) /* no bitrate? */
return false;
if ((head & SAMPLERATE_MASK) == SAMPLERATE_MASK) /* bad sample rate? */
return false;
if (((head >> 19) & 1) == 1 &&
((head >> 17) & 3) == 3 &&
((head >> 16) & 1) == 1)
return false;
if ((head & 0xffff0000) == 0xfffe0000)
return false;
return true;
}
static bool mp3headerinfo(struct mp3info *info, unsigned long header)
{
int bittable = 0;
int bitindex;
int freqindex;
/* MPEG Audio Version */
switch(header & VERSION_MASK) {
case 0:
/* MPEG version 2.5 is not an official standard */
info->version = MPEG_VERSION2_5;
bittable = MPEG_VERSION2 - 1; /* use the V2 bit rate table */
break;
case (1 << 19):
return false;
case (2 << 19):
/* MPEG version 2 (ISO/IEC 13818-3) */
info->version = MPEG_VERSION2;
bittable = MPEG_VERSION2 - 1;
break;
case (3 << 19):
/* MPEG version 1 (ISO/IEC 11172-3) */
info->version = MPEG_VERSION1;
bittable = MPEG_VERSION1 - 1;
break;
}
switch(header & LAYER_MASK) {
case 0:
return false;
case (1 << 17):
info->layer = 2;
break;
case (2 << 17):
info->layer = 1;
break;
case (3 << 17):
info->layer = 0;
break;
}
info->protection = (header & PROTECTION_MASK)?true:false;
/* Bitrate */
bitindex = (header & 0xf000) >> 12;
info->bitrate = bitrate_table[bittable][info->layer][bitindex];
if(info->bitrate == 0)
return false;
/* Sampling frequency */
freqindex = (header & 0x0C00) >> 10;
info->frequency = freqtab[info->version][freqindex];
if(info->frequency == 0)
return false;
info->padding = (header & 0x0200)?1:0;
/* Calculate number of bytes, calculation depends on layer */
switch(info->layer) {
case 0:
info->frame_size = info->bitrate * 48000;
info->frame_size /=
freqtab[info->version][freqindex] << bittable;
break;
case 1:
case 2:
info->frame_size = info->bitrate * 144000;
info->frame_size /=
freqtab[info->version][freqindex] << bittable;
break;
default:
info->frame_size = 1;
}
info->frame_size += info->padding;
/* Calculate time per frame */
info->frame_time = bs[info->layer] /
(freqtab[info->version][freqindex] << bittable);
info->channel_mode = (header & 0xc0) >> 6;
info->mode_extension = (header & 0x30) >> 4;
info->emphasis = header & 3;
#ifdef DEBUG_VERBOSE
DEBUGF( "Header: %08x, Ver %d, lay %d, bitr %d, freq %d, "
"chmode %d, mode_ext %d, emph %d, bytes: %d time: %d\n",
header, info->version, info->layer, info->bitrate, info->frequency,
info->channel_mode, info->mode_extension,
info->emphasis, info->frame_size, info->frame_time);
#endif
return true;
}
unsigned long find_next_frame(int fd, int *offset, int max_offset, unsigned long last_header)
{
unsigned long header=0;
unsigned char tmp;
int i;
int pos = 0;
/* We remember the last header we found, to use as a template to see if
the header we find has the same frequency, layer etc */
last_header &= 0xffff0c00;
/* Fill up header with first 24 bits */
for(i = 0; i < 3; i++) {
header <<= 8;
if(!read(fd, &tmp, 1))
return 0;
header |= tmp;
pos++;
}
do {
header <<= 8;
if(!read(fd, &tmp, 1))
return 0;
header |= tmp;
pos++;
if(max_offset > 0 && pos > max_offset)
return 0;
} while(!is_mp3frameheader(header) ||
(last_header?((header & 0xffff0c00) != last_header):false));
*offset = pos - 4;
#ifdef DEBUG
if(*offset)
DEBUGF("Warning: skipping %d bytes of garbage\n", *offset);
#endif
return header;
}
#ifdef SIMULATOR
unsigned char mp3buf[0x100000];
unsigned char mp3end[1];
#else
extern unsigned char mp3buf[];
extern unsigned char mp3end[];
#endif
static int fnf_read_index;
static int fnf_buf_len;
static int buf_getbyte(int fd, unsigned char *c)
{
if(fnf_read_index < fnf_buf_len)
{
*c = mp3buf[fnf_read_index++];
return 1;
}
else
{
fnf_buf_len = read(fd, mp3buf, mp3end - mp3buf);
if(fnf_buf_len < 0)
return -1;
fnf_read_index = 0;
if(fnf_buf_len > 0)
{
*c = mp3buf[fnf_read_index++];
return 1;
}
else
return 0;
}
return 0;
}
static int buf_seek(int fd, int len)
{
fnf_read_index += len;
if(fnf_read_index > fnf_buf_len)
{
len = fnf_read_index - fnf_buf_len;
fnf_buf_len = read(fd, mp3buf, mp3end - mp3buf);
if(fnf_buf_len < 0)
return -1;
fnf_read_index = 0;
fnf_read_index += len;
}
if(fnf_read_index > fnf_buf_len)
{
return -1;
}
else
return 0;
}
static void buf_init(void)
{
fnf_buf_len = 0;
fnf_read_index = 0;
}
unsigned long buf_find_next_frame(int fd, int *offset, int max_offset,
unsigned long last_header)
{
unsigned long header=0;
unsigned char tmp;
int i;
int pos = 0;
/* We remember the last header we found, to use as a template to see if
the header we find has the same frequency, layer etc */
last_header &= 0xffff0c00;
/* Fill up header with first 24 bits */
for(i = 0; i < 3; i++) {
header <<= 8;
if(!buf_getbyte(fd, &tmp))
return 0;
header |= tmp;
pos++;
}
do {
header <<= 8;
if(!buf_getbyte(fd, &tmp))
return 0;
header |= tmp;
pos++;
if(max_offset > 0 && pos > max_offset)
return 0;
} while(!is_mp3frameheader(header) ||
(last_header?((header & 0xffff0c00) != last_header):false));
*offset = pos - 4;
#ifdef DEBUG
if(*offset)
DEBUGF("Warning: skipping %d bytes of garbage\n", *offset);
#endif
return header;
}
int get_mp3file_info(int fd, struct mp3info *info)
{
unsigned char frame[1024];
unsigned char *vbrheader;
unsigned long header;
int bytecount;
int num_offsets;
int frames_per_entry;
int i;
int offset;
int j;
int tmp;
header = find_next_frame(fd, &bytecount, 0x20000, 0);
/* Quit if we haven't found a valid header within 128K */
if(header == 0)
return -1;
memset(info, 0, sizeof(struct mp3info));
if(!mp3headerinfo(info, header))
return -2;
/* OK, we have found a frame. Let's see if it has a Xing header */
if(read(fd, frame, info->frame_size-4) < 0)
return -3;
/* calculate position of VBR header */
if ( info->version == MPEG_VERSION1 ) {
if (info->channel_mode == 3) /* mono */
vbrheader = frame + 17;
else
vbrheader = frame + 32;
}
else {
if (info->channel_mode == 3) /* mono */
vbrheader = frame + 9;
else
vbrheader = frame + 17;
}
if (vbrheader[0] == 'X' &&
vbrheader[1] == 'i' &&
vbrheader[2] == 'n' &&
vbrheader[3] == 'g')
{
int i = 8; /* Where to start parsing info */
DEBUGF("Xing header\n");
/* Remember where in the file the Xing header is */
info->vbr_header_pos = lseek(fd, 0, SEEK_CUR) - info->frame_size;
/* We want to skip the Xing frame when playing the stream */
bytecount += info->frame_size;
/* Now get the next frame to find out the real info about
the mp3 stream */
header = find_next_frame(fd, &tmp, 0x20000, 0);
if(header == 0)
return -4;
if(!mp3headerinfo(info, header))
return -5;
/* Yes, it is a VBR file */
info->is_vbr = true;
info->is_xing_vbr = true;
if(vbrheader[7] & VBR_FRAMES_FLAG) /* Is the frame count there? */
{
info->frame_count = BYTES2INT(vbrheader[i], vbrheader[i+1],
vbrheader[i+2], vbrheader[i+3]);
info->file_time = info->frame_count * info->frame_time;
i += 4;
}
if(vbrheader[7] & VBR_BYTES_FLAG) /* Is byte count there? */
{
info->byte_count = BYTES2INT(vbrheader[i], vbrheader[i+1],
vbrheader[i+2], vbrheader[i+3]);
i += 4;
}
if(info->file_time && info->byte_count)
info->bitrate = info->byte_count * 8 / info->file_time;
else
info->bitrate = 0;
if(vbrheader[7] & VBR_TOC_FLAG) /* Is table-of-contents there? */
{
memcpy( info->toc, vbrheader+i, 100 );
}
}
if (vbrheader[0] == 'V' &&
vbrheader[1] == 'B' &&
vbrheader[2] == 'R' &&
vbrheader[3] == 'I')
{
DEBUGF("VBRI header\n");
/* We want to skip the VBRI frame when playing the stream */
bytecount += info->frame_size;
/* Now get the next frame to find out the real info about
the mp3 stream */
header = find_next_frame(fd, &bytecount, 0x20000, 0);
if(header == 0)
return -6;
if(!mp3headerinfo(info, header))
return -7;
DEBUGF("%04x: %04x %04x ", 0, header >> 16, header & 0xffff);
for(i = 4;i < (int)sizeof(frame)-4;i+=2) {
if(i % 16 == 0) {
DEBUGF("\n%04x: ", i-4);
}
DEBUGF("%04x ", (frame[i-4] << 8) | frame[i-4+1]);
}
DEBUGF("\n");
/* Yes, it is a FhG VBR file */
info->is_vbr = true;
info->is_vbri_vbr = true;
info->has_toc = false; /* We don't parse the TOC (yet) */
info->byte_count = BYTES2INT(vbrheader[10], vbrheader[11],
vbrheader[12], vbrheader[13]);
info->frame_count = BYTES2INT(vbrheader[14], vbrheader[15],
vbrheader[16], vbrheader[17]);
info->file_time = info->frame_count * info->frame_time;
info->bitrate = info->byte_count * 8 / info->file_time;
/* We don't parse the TOC, since we don't yet know how to (FIXME) */
num_offsets = BYTES2INT(0, 0, vbrheader[18], vbrheader[19]);
frames_per_entry = BYTES2INT(0, 0, vbrheader[24], vbrheader[25]);
DEBUGF("Frame size (%dkpbs): %d bytes (0x%x)\n",
info->bitrate, info->frame_size, info->frame_size);
DEBUGF("Frame count: %x\n", info->frame_count);
DEBUGF("Byte count: %x\n", info->byte_count);
DEBUGF("Offsets: %d\n", num_offsets);
DEBUGF("Frames/entry: %d\n", frames_per_entry);
offset = 0;
for(i = 0;i < num_offsets;i++)
{
j = BYTES2INT(0, 0, vbrheader[26+i*2], vbrheader[27+i*2]);
offset += j;
DEBUGF("%03d: %x (%x)\n", i, offset - bytecount, j);
}
}
/* Is it a LAME Info frame? */
if (vbrheader[0] == 'I' &&
vbrheader[1] == 'n' &&
vbrheader[2] == 'f' &&
vbrheader[3] == 'o')
{
/* Make sure we skip this frame in playback */
bytecount += info->frame_size;
}
return bytecount;
}
/* This is an MP3 header, 128kbit/s, 44.1kHz, with silence */
static const unsigned char xing_frame_header[] = {
0xff, 0xfa, 0x90, 0x64, 0x86, 0x1f
};
static const char cooltext[] = "Rockbox rocks";
static void int2bytes(unsigned char *buf, int val)
{
buf[0] = (val >> 24) & 0xff;
buf[1] = (val >> 16) & 0xff;
buf[2] = (val >> 8) & 0xff;
buf[3] = val & 0xff;
}
int count_mp3_frames(int fd, int startpos, int filesize,
void (*progressfunc)(int))
{
unsigned long header = 0;
struct mp3info info;
int num_frames;
int bytes;
int cnt;
int progress_chunk = filesize / 50; /* Max is 50%, in 1% increments */
int progress_cnt = 0;
bool is_vbr = false;
int last_bitrate = 0;
if(lseek(fd, startpos, SEEK_SET) < 0)
return -1;
buf_init();
/* Find out the total number of frames */
num_frames = 0;
cnt = 0;
while((header = buf_find_next_frame(fd, &bytes, -1, header))) {
mp3headerinfo(&info, header);
/* See if this really is a VBR file */
if(last_bitrate && info.bitrate != last_bitrate)
{
is_vbr = true;
}
last_bitrate = info.bitrate;
buf_seek(fd, info.frame_size-4);
num_frames++;
if(progressfunc)
{
cnt += bytes + info.frame_size;
if(cnt > progress_chunk)
{
progress_cnt++;
progressfunc(progress_cnt);
cnt = 0;
}
}
}
DEBUGF("Total number of frames: %d\n", num_frames);
if(is_vbr)
return num_frames;
else
{
DEBUGF("Not a VBR file\n");
return 0;
}
}
int create_xing_header(int fd, int startpos, int filesize,
unsigned char *buf, int num_frames,
void (*progressfunc)(int), bool generate_toc)
{
unsigned long header = 0;
struct mp3info info;
int pos, last_pos;
int i, j;
int bytes;
int filepos;
int tocentry;
int x;
int index;
DEBUGF("create_xing_header()\n");
/* Create the frame header */
memset(buf, 0, 417);
memcpy(buf, xing_frame_header, 6);
lseek(fd, startpos, SEEK_SET);
buf_init();
buf[36] = 'X';
buf[36+1] = 'i';
buf[36+2] = 'n';
buf[36+3] = 'g';
int2bytes(&buf[36+4], (num_frames?VBR_FRAMES_FLAG:0 |
filesize?VBR_BYTES_FLAG:0 |
generate_toc?VBR_TOC_FLAG:0));
index = 36+8;
if(num_frames)
{
int2bytes(&buf[index], num_frames);
index += 4;
}
if(filesize)
{
int2bytes(&buf[index], filesize - startpos);
index += 4;
}
if(generate_toc)
{
/* Generate filepos table */
last_pos = 0;
filepos = 0;
header = 0;
x = 0;
for(i = 0;i < 100;i++) {
/* Calculate the absolute frame number for this seek point */
pos = i * num_frames / 100;
/* Advance from the last seek point to this one */
for(j = 0;j < pos - last_pos;j++)
{
DEBUGF("fpos: %x frame no: %x ", filepos, x++);
header = buf_find_next_frame(fd, &bytes, -1, header);
mp3headerinfo(&info, header);
buf_seek(fd, info.frame_size-4);
filepos += info.frame_size;
}
if(progressfunc)
{
progressfunc(50 + i/2);
}
tocentry = filepos * 256 / filesize;
DEBUGF("Pos %d: %d relpos: %d filepos: %x tocentry: %x\n",
i, pos, pos-last_pos, filepos, tocentry);
/* Fill in the TOC entry */
buf[index + i] = tocentry;
last_pos = pos;
}
}
memcpy(buf + index + 100, cooltext, sizeof(cooltext));
#ifdef DEBUG
for(i = 0;i < 417;i++)
{
if(i && !(i % 16))
DEBUGF("\n");
DEBUGF("%02x ", buf[i]);
}
#endif
return 0;
}