7f971e0176
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@22211 a1c6a512-1295-4272-9138-f99709370657
512 lines
17 KiB
C
512 lines
17 KiB
C
/***************************************************************************
|
|
* __________ __ ___.
|
|
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
|
|
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
|
|
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
|
|
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
|
|
* \/ \/ \/ \/ \/
|
|
* $Id$
|
|
*
|
|
* Copyright (C) 2005 Dave Chapman
|
|
*
|
|
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
|
|
* KIND, either express or implied.
|
|
*
|
|
****************************************************************************/
|
|
|
|
#include "codeclib.h"
|
|
#include <codecs/libffmpegFLAC/decoder.h>
|
|
|
|
CODEC_HEADER
|
|
|
|
/* The output buffers containing the decoded samples (channels 0 and 1) */
|
|
int32_t decoded0[MAX_BLOCKSIZE] IBSS_ATTR_FLAC_DECODED0;
|
|
int32_t decoded1[MAX_BLOCKSIZE] IBSS_ATTR;
|
|
|
|
#define MAX_SUPPORTED_SEEKTABLE_SIZE 5000
|
|
|
|
/* Notes about seeking:
|
|
|
|
The full seek table consists of:
|
|
uint64_t sample (only 36 bits are used)
|
|
uint64_t offset
|
|
uint32_t blocksize
|
|
|
|
We also limit the sample and offset values to 32-bits - Rockbox doesn't
|
|
support files bigger than 2GB on FAT32 filesystems.
|
|
|
|
The reference FLAC encoder produces a seek table with points every
|
|
10 seconds, but this can be overridden by the user when encoding a file.
|
|
|
|
With the default settings, a typical 4 minute track will contain
|
|
24 seek points.
|
|
|
|
Taking the extreme case of a Rockbox supported file to be a 2GB (compressed)
|
|
16-bit/44.1KHz mono stream with a likely uncompressed size of 4GB:
|
|
Total duration is: 48694 seconds (about 810 minutes - 13.5 hours)
|
|
Total number of seek points: 4869
|
|
|
|
Therefore we limit the number of seek points to 5000. This is a
|
|
very extreme case, and requires 5000*8=40000 bytes of storage.
|
|
|
|
If we come across a FLAC file with more than this number of seekpoints, we
|
|
just use the first 5000.
|
|
|
|
*/
|
|
|
|
struct FLACseekpoints {
|
|
uint32_t sample;
|
|
uint32_t offset;
|
|
uint16_t blocksize;
|
|
};
|
|
|
|
struct FLACseekpoints seekpoints[MAX_SUPPORTED_SEEKTABLE_SIZE];
|
|
int nseekpoints;
|
|
|
|
static int8_t *bit_buffer;
|
|
static size_t buff_size;
|
|
|
|
static bool flac_init(FLACContext* fc, int first_frame_offset)
|
|
{
|
|
unsigned char buf[255];
|
|
bool found_streaminfo=false;
|
|
uint32_t seekpoint_hi,seekpoint_lo;
|
|
uint32_t offset_hi,offset_lo;
|
|
uint16_t blocksize;
|
|
int endofmetadata=0;
|
|
uint32_t blocklength;
|
|
|
|
ci->memset(fc,0,sizeof(FLACContext));
|
|
nseekpoints=0;
|
|
|
|
fc->sample_skip = 0;
|
|
|
|
/* Skip any foreign tags at start of file */
|
|
ci->seek_buffer(first_frame_offset);
|
|
|
|
fc->metadatalength = first_frame_offset;
|
|
|
|
if (ci->read_filebuf(buf, 4) < 4)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
if (ci->memcmp(buf,"fLaC",4) != 0)
|
|
{
|
|
return false;
|
|
}
|
|
fc->metadatalength += 4;
|
|
|
|
while (!endofmetadata) {
|
|
if (ci->read_filebuf(buf, 4) < 4)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
endofmetadata=(buf[0]&0x80);
|
|
blocklength = (buf[1] << 16) | (buf[2] << 8) | buf[3];
|
|
fc->metadatalength+=blocklength+4;
|
|
|
|
if ((buf[0] & 0x7f) == 0) /* 0 is the STREAMINFO block */
|
|
{
|
|
if (ci->read_filebuf(buf, blocklength) < blocklength) return false;
|
|
|
|
fc->filesize = ci->filesize;
|
|
fc->min_blocksize = (buf[0] << 8) | buf[1];
|
|
fc->max_blocksize = (buf[2] << 8) | buf[3];
|
|
fc->min_framesize = (buf[4] << 16) | (buf[5] << 8) | buf[6];
|
|
fc->max_framesize = (buf[7] << 16) | (buf[8] << 8) | buf[9];
|
|
fc->samplerate = (buf[10] << 12) | (buf[11] << 4)
|
|
| ((buf[12] & 0xf0) >> 4);
|
|
fc->channels = ((buf[12]&0x0e)>>1) + 1;
|
|
fc->bps = (((buf[12]&0x01) << 4) | ((buf[13]&0xf0)>>4) ) + 1;
|
|
|
|
/* totalsamples is a 36-bit field, but we assume <= 32 bits are
|
|
used */
|
|
fc->totalsamples = (buf[14] << 24) | (buf[15] << 16)
|
|
| (buf[16] << 8) | buf[17];
|
|
|
|
/* Calculate track length (in ms) and estimate the bitrate
|
|
(in kbit/s) */
|
|
fc->length = ((int64_t) fc->totalsamples * 1000) / fc->samplerate;
|
|
|
|
found_streaminfo=true;
|
|
} else if ((buf[0] & 0x7f) == 3) { /* 3 is the SEEKTABLE block */
|
|
while ((nseekpoints < MAX_SUPPORTED_SEEKTABLE_SIZE) &&
|
|
(blocklength >= 18)) {
|
|
if (ci->read_filebuf(buf,18) < 18) return false;
|
|
blocklength-=18;
|
|
|
|
seekpoint_hi=(buf[0] << 24) | (buf[1] << 16) |
|
|
(buf[2] << 8) | buf[3];
|
|
seekpoint_lo=(buf[4] << 24) | (buf[5] << 16) |
|
|
(buf[6] << 8) | buf[7];
|
|
offset_hi=(buf[8] << 24) | (buf[9] << 16) |
|
|
(buf[10] << 8) | buf[11];
|
|
offset_lo=(buf[12] << 24) | (buf[13] << 16) |
|
|
(buf[14] << 8) | buf[15];
|
|
|
|
blocksize=(buf[16] << 8) | buf[17];
|
|
|
|
/* Only store seekpoints where the high 32 bits are zero */
|
|
if ((seekpoint_hi == 0) && (seekpoint_lo != 0xffffffff) &&
|
|
(offset_hi == 0)) {
|
|
seekpoints[nseekpoints].sample=seekpoint_lo;
|
|
seekpoints[nseekpoints].offset=offset_lo;
|
|
seekpoints[nseekpoints].blocksize=blocksize;
|
|
nseekpoints++;
|
|
}
|
|
}
|
|
/* Skip any unread seekpoints */
|
|
if (blocklength > 0)
|
|
ci->advance_buffer(blocklength);
|
|
} else {
|
|
/* Skip to next metadata block */
|
|
ci->advance_buffer(blocklength);
|
|
}
|
|
}
|
|
|
|
if (found_streaminfo) {
|
|
fc->bitrate = ((int64_t) (fc->filesize-fc->metadatalength) * 8)
|
|
/ fc->length;
|
|
return true;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/* Synchronize to next frame in stream - adapted from libFLAC 1.1.3b2 */
|
|
static bool frame_sync(FLACContext* fc) {
|
|
unsigned int x = 0;
|
|
bool cached = false;
|
|
|
|
/* Make sure we're byte aligned. */
|
|
align_get_bits(&fc->gb);
|
|
|
|
while(1) {
|
|
if(fc->gb.size_in_bits - get_bits_count(&fc->gb) < 8) {
|
|
/* Error, end of bitstream, a valid stream should never reach here
|
|
* since the buffer should contain at least one frame header.
|
|
*/
|
|
return false;
|
|
}
|
|
|
|
if(cached)
|
|
cached = false;
|
|
else
|
|
x = get_bits(&fc->gb, 8);
|
|
|
|
if(x == 0xff) { /* MAGIC NUMBER for first 8 frame sync bits. */
|
|
x = get_bits(&fc->gb, 8);
|
|
/* We have to check if we just read two 0xff's in a row; the second
|
|
* may actually be the beginning of the sync code.
|
|
*/
|
|
if(x == 0xff) { /* MAGIC NUMBER for first 8 frame sync bits. */
|
|
cached = true;
|
|
}
|
|
else if(x >> 2 == 0x3e) { /* MAGIC NUMBER for last 6 sync bits. */
|
|
/* Succesfully synced. */
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Advance and init bit buffer to the new frame. */
|
|
ci->advance_buffer((get_bits_count(&fc->gb)-16)>>3); /* consumed bytes */
|
|
bit_buffer = ci->request_buffer(&buff_size, MAX_FRAMESIZE+16);
|
|
init_get_bits(&fc->gb, bit_buffer, buff_size*8);
|
|
|
|
/* Decode the frame to verify the frame crc and
|
|
* fill fc with its metadata.
|
|
*/
|
|
if(flac_decode_frame(fc, decoded0, decoded1,
|
|
bit_buffer, buff_size, ci->yield) < 0) {
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/* Seek to sample - adapted from libFLAC 1.1.3b2+ */
|
|
static bool flac_seek(FLACContext* fc, uint32_t target_sample) {
|
|
off_t orig_pos = ci->curpos;
|
|
off_t pos = -1;
|
|
unsigned long lower_bound, upper_bound;
|
|
unsigned long lower_bound_sample, upper_bound_sample;
|
|
int i;
|
|
unsigned approx_bytes_per_frame;
|
|
uint32_t this_frame_sample = fc->samplenumber;
|
|
unsigned this_block_size = fc->blocksize;
|
|
bool needs_seek = true, first_seek = true;
|
|
|
|
/* We are just guessing here. */
|
|
if(fc->max_framesize > 0)
|
|
approx_bytes_per_frame = (fc->max_framesize + fc->min_framesize)/2 + 1;
|
|
/* Check if it's a known fixed-blocksize stream. */
|
|
else if(fc->min_blocksize == fc->max_blocksize && fc->min_blocksize > 0)
|
|
approx_bytes_per_frame = fc->min_blocksize*fc->channels*fc->bps/8 + 64;
|
|
else
|
|
approx_bytes_per_frame = 4608 * fc->channels * fc->bps/8 + 64;
|
|
|
|
/* Set an upper and lower bound on where in the stream we will search. */
|
|
lower_bound = fc->metadatalength;
|
|
lower_bound_sample = 0;
|
|
upper_bound = fc->filesize;
|
|
upper_bound_sample = fc->totalsamples>0 ? fc->totalsamples : target_sample;
|
|
|
|
/* Refine the bounds if we have a seektable with suitable points. */
|
|
if(nseekpoints > 0) {
|
|
/* Find the closest seek point <= target_sample, if it exists. */
|
|
for(i = nseekpoints-1; i >= 0; i--) {
|
|
if(seekpoints[i].sample <= target_sample)
|
|
break;
|
|
}
|
|
if(i >= 0) { /* i.e. we found a suitable seek point... */
|
|
lower_bound = fc->metadatalength + seekpoints[i].offset;
|
|
lower_bound_sample = seekpoints[i].sample;
|
|
}
|
|
|
|
/* Find the closest seek point > target_sample, if it exists. */
|
|
for(i = 0; i < nseekpoints; i++) {
|
|
if(seekpoints[i].sample > target_sample)
|
|
break;
|
|
}
|
|
if(i < nseekpoints) { /* i.e. we found a suitable seek point... */
|
|
upper_bound = fc->metadatalength + seekpoints[i].offset;
|
|
upper_bound_sample = seekpoints[i].sample;
|
|
}
|
|
}
|
|
|
|
while(1) {
|
|
/* Check if bounds are still ok. */
|
|
if(lower_bound_sample >= upper_bound_sample ||
|
|
lower_bound > upper_bound) {
|
|
return false;
|
|
}
|
|
|
|
/* Calculate new seek position */
|
|
if(needs_seek) {
|
|
pos = (off_t)(lower_bound +
|
|
(((target_sample - lower_bound_sample) *
|
|
(int64_t)(upper_bound - lower_bound)) /
|
|
(upper_bound_sample - lower_bound_sample)) -
|
|
approx_bytes_per_frame);
|
|
|
|
if(pos >= (off_t)upper_bound)
|
|
pos = (off_t)upper_bound-1;
|
|
if(pos < (off_t)lower_bound)
|
|
pos = (off_t)lower_bound;
|
|
}
|
|
|
|
if(!ci->seek_buffer(pos))
|
|
return false;
|
|
|
|
bit_buffer = ci->request_buffer(&buff_size, MAX_FRAMESIZE+16);
|
|
init_get_bits(&fc->gb, bit_buffer, buff_size*8);
|
|
|
|
/* Now we need to get a frame. It is possible for our seek
|
|
* to land in the middle of audio data that looks exactly like
|
|
* a frame header from a future version of an encoder. When
|
|
* that happens, frame_sync() will return false.
|
|
* But there is a remote possibility that it is properly
|
|
* synced at such a "future-codec frame", so to make sure,
|
|
* we wait to see several "unparseable" errors in a row before
|
|
* bailing out.
|
|
*/
|
|
{
|
|
unsigned unparseable_count;
|
|
bool got_a_frame = false;
|
|
for(unparseable_count = 0; !got_a_frame
|
|
&& unparseable_count < 10; unparseable_count++) {
|
|
if(frame_sync(fc))
|
|
got_a_frame = true;
|
|
}
|
|
if(!got_a_frame) {
|
|
ci->seek_buffer(orig_pos);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
this_frame_sample = fc->samplenumber;
|
|
this_block_size = fc->blocksize;
|
|
|
|
if(target_sample >= this_frame_sample
|
|
&& target_sample < this_frame_sample+this_block_size) {
|
|
/* Found the frame containing the target sample. */
|
|
fc->sample_skip = target_sample - this_frame_sample;
|
|
break;
|
|
}
|
|
|
|
if(this_frame_sample + this_block_size >= upper_bound_sample &&
|
|
!first_seek) {
|
|
if(pos == (off_t)lower_bound || !needs_seek) {
|
|
ci->seek_buffer(orig_pos);
|
|
return false;
|
|
}
|
|
/* Our last move backwards wasn't big enough, try again. */
|
|
approx_bytes_per_frame *= 2;
|
|
continue;
|
|
}
|
|
/* Allow one seek over upper bound,
|
|
* required for streams with unknown total samples.
|
|
*/
|
|
first_seek = false;
|
|
|
|
/* Make sure we are not seeking in a corrupted stream */
|
|
if(this_frame_sample < lower_bound_sample) {
|
|
ci->seek_buffer(orig_pos);
|
|
return false;
|
|
}
|
|
|
|
approx_bytes_per_frame = this_block_size*fc->channels*fc->bps/8 + 64;
|
|
|
|
/* We need to narrow the search. */
|
|
if(target_sample < this_frame_sample) {
|
|
upper_bound_sample = this_frame_sample;
|
|
upper_bound = ci->curpos;
|
|
}
|
|
else { /* Target is beyond this frame. */
|
|
/* We are close, continue in decoding next frames. */
|
|
if(target_sample < this_frame_sample + 4*this_block_size) {
|
|
pos = ci->curpos + fc->framesize;
|
|
needs_seek = false;
|
|
}
|
|
|
|
lower_bound_sample = this_frame_sample + this_block_size;
|
|
lower_bound = ci->curpos + fc->framesize;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/* Seek to file offset */
|
|
static bool flac_seek_offset(FLACContext* fc, uint32_t offset) {
|
|
unsigned unparseable_count;
|
|
bool got_a_frame = false;
|
|
|
|
if(!ci->seek_buffer(offset))
|
|
return false;
|
|
|
|
bit_buffer = ci->request_buffer(&buff_size, MAX_FRAMESIZE);
|
|
init_get_bits(&fc->gb, bit_buffer, buff_size*8);
|
|
|
|
for(unparseable_count = 0; !got_a_frame
|
|
&& unparseable_count < 10; unparseable_count++) {
|
|
if(frame_sync(fc))
|
|
got_a_frame = true;
|
|
}
|
|
|
|
if(!got_a_frame) {
|
|
ci->seek_buffer(fc->metadatalength);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/* this is the codec entry point */
|
|
enum codec_status codec_main(void)
|
|
{
|
|
int8_t *buf;
|
|
FLACContext fc;
|
|
uint32_t samplesdone = 0;
|
|
uint32_t elapsedtime;
|
|
size_t bytesleft;
|
|
int consumed;
|
|
int res;
|
|
int frame;
|
|
int retval;
|
|
|
|
/* Generic codec initialisation */
|
|
ci->configure(DSP_SET_SAMPLE_DEPTH, FLAC_OUTPUT_DEPTH-1);
|
|
|
|
next_track:
|
|
|
|
/* Need to save offset for later use (cleared indirectly by flac_init) */
|
|
samplesdone=ci->id3->offset;
|
|
|
|
if (codec_init()) {
|
|
LOGF("FLAC: Error initialising codec\n");
|
|
retval = CODEC_ERROR;
|
|
goto exit;
|
|
}
|
|
|
|
while (!*ci->taginfo_ready && !ci->stop_codec)
|
|
ci->sleep(1);
|
|
|
|
if (!flac_init(&fc,ci->id3->first_frame_offset)) {
|
|
LOGF("FLAC: Error initialising codec\n");
|
|
retval = CODEC_ERROR;
|
|
goto done;
|
|
}
|
|
|
|
ci->configure(DSP_SWITCH_FREQUENCY, ci->id3->frequency);
|
|
ci->configure(DSP_SET_STEREO_MODE, fc.channels == 1 ?
|
|
STEREO_MONO : STEREO_NONINTERLEAVED);
|
|
codec_set_replaygain(ci->id3);
|
|
|
|
if (samplesdone) {
|
|
flac_seek_offset(&fc, samplesdone);
|
|
samplesdone=0;
|
|
}
|
|
|
|
/* The main decoding loop */
|
|
frame=0;
|
|
buf = ci->request_buffer(&bytesleft, MAX_FRAMESIZE);
|
|
while (bytesleft) {
|
|
ci->yield();
|
|
if (ci->stop_codec || ci->new_track) {
|
|
break;
|
|
}
|
|
|
|
/* Deal with any pending seek requests */
|
|
if (ci->seek_time) {
|
|
if (flac_seek(&fc,(uint32_t)(((uint64_t)(ci->seek_time-1)
|
|
*ci->id3->frequency)/1000))) {
|
|
/* Refill the input buffer */
|
|
buf = ci->request_buffer(&bytesleft, MAX_FRAMESIZE);
|
|
}
|
|
ci->seek_complete();
|
|
}
|
|
|
|
if((res=flac_decode_frame(&fc,decoded0,decoded1,buf,
|
|
bytesleft,ci->yield)) < 0) {
|
|
LOGF("FLAC: Frame %d, error %d\n",frame,res);
|
|
retval = CODEC_ERROR;
|
|
goto done;
|
|
}
|
|
consumed=fc.gb.index/8;
|
|
frame++;
|
|
|
|
ci->yield();
|
|
ci->pcmbuf_insert(&decoded0[fc.sample_skip], &decoded1[fc.sample_skip],
|
|
fc.blocksize - fc.sample_skip);
|
|
|
|
fc.sample_skip = 0;
|
|
|
|
/* Update the elapsed-time indicator */
|
|
samplesdone=fc.samplenumber+fc.blocksize;
|
|
elapsedtime=(samplesdone*10)/(ci->id3->frequency/100);
|
|
ci->set_elapsed(elapsedtime);
|
|
|
|
ci->advance_buffer(consumed);
|
|
|
|
buf = ci->request_buffer(&bytesleft, MAX_FRAMESIZE);
|
|
}
|
|
retval = CODEC_OK;
|
|
|
|
done:
|
|
LOGF("FLAC: Decoded %ld samples\n",samplesdone);
|
|
|
|
if (ci->request_next_track())
|
|
goto next_track;
|
|
|
|
exit:
|
|
return retval;
|
|
}
|