rockbox/lib/rbcodec/codecs/ape.c
Michael Sevakis 31b7122867 Implement time-based resume and playback start.
This complements offset-based resume and playback start funcionality.
The implementation is global on both HWCODEC and SWCODEC.

Basically, if either the specified elapsed or offset are non-zero,
it indicates a mid-track resume.

To resume by time only, set elapsed to nonzero and offset to zero.
To resume by offset only, set offset to nonzero and elapsed to zero.

Which one the codec uses and which has priority is up to the codec;
however, using an elapsed time covers more cases:

* Codecs not able to use an offset such as VGM or other atomic
formats

* Starting playback at a nonzero elapsed time from a source that
contains no offset, such as a cuesheet

The change re-versions pretty much everything from tagcache to nvram.

Change-Id: Ic7aebb24e99a03ae99585c5e236eba960d163f38
Reviewed-on: http://gerrit.rockbox.org/516
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested: Michael Sevakis <jethead71@rockbox.org>
2014-03-10 04:12:30 +01:00

350 lines
11 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2007 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/demac/libdemac/demac.h>
CODEC_HEADER
#define BLOCKS_PER_LOOP 1024
#define MAX_CHANNELS 2
#define MAX_BYTESPERSAMPLE 3
/* Monkey's Audio files have one seekpoint per frame. The framesize
varies between 73728 and 1179648 samples.
At the smallest framesize, 30000 frames would be 50155 seconds of
audio - almost 14 hours. This should be enough for any file a user
would want to play in Rockbox, given the 2GB FAT filesize (and 4GB
seektable entry size) limit.
This means the seektable is 120000 bytes, but we have a lot of
spare room in the codec buffer - the APE codec itself is small.
*/
#define MAX_SEEKPOINTS 30000
static uint32_t seektablebuf[MAX_SEEKPOINTS];
#define INPUT_CHUNKSIZE (32*1024)
/* 1024*4 = 4096 bytes per channel */
static int32_t decoded0[BLOCKS_PER_LOOP] IBSS_ATTR;
static int32_t decoded1[BLOCKS_PER_LOOP] IBSS_ATTR;
#define MAX_SUPPORTED_SEEKTABLE_SIZE 5000
/* Given an ape_ctx and a sample to seek to, return the file position
to the frame containing that sample, and the number of samples to
skip in that frame.
*/
static bool ape_calc_seekpos(struct ape_ctx_t* ape_ctx,
uint32_t new_sample,
uint32_t* newframe,
uint32_t* filepos,
uint32_t* samplestoskip)
{
uint32_t n;
n = new_sample / ape_ctx->blocksperframe;
if (n >= ape_ctx->numseekpoints)
{
/* We don't have a seekpoint for that frame */
return false;
}
*newframe = n;
*filepos = ape_ctx->seektable[n];
*samplestoskip = new_sample - (n * ape_ctx->blocksperframe);
return true;
}
/* The resume offset is a value in bytes - we need to
turn it into a frame number and samplestoskip value */
static void ape_resume(struct ape_ctx_t* ape_ctx, size_t resume_offset,
uint32_t* currentframe, uint32_t* samplesdone,
uint32_t* samplestoskip, int* firstbyte)
{
off_t newfilepos;
int64_t framesize;
int64_t offset;
*currentframe = 0;
*samplesdone = 0;
*samplestoskip = 0;
while ((*currentframe < ape_ctx->totalframes) &&
(*currentframe < ape_ctx->numseekpoints) &&
(resume_offset > ape_ctx->seektable[*currentframe]))
{
++*currentframe;
*samplesdone += ape_ctx->blocksperframe;
}
if ((*currentframe > 0) &&
(ape_ctx->seektable[*currentframe] > resume_offset)) {
--*currentframe;
*samplesdone -= ape_ctx->blocksperframe;
}
newfilepos = ape_ctx->seektable[*currentframe];
/* APE's bytestream is weird... */
*firstbyte = 3 - (newfilepos & 3);
newfilepos &= ~3;
ci->seek_buffer(newfilepos);
/* We estimate where we were in the current frame, based on the
byte offset */
if (*currentframe < (ape_ctx->totalframes - 1)) {
framesize = ape_ctx->seektable[*currentframe+1] - ape_ctx->seektable[*currentframe];
offset = resume_offset - ape_ctx->seektable[*currentframe];
*samplestoskip = (offset * ape_ctx->blocksperframe) / framesize;
}
}
/* this is the codec entry point */
enum codec_status codec_main(enum codec_entry_call_reason reason)
{
if (reason == CODEC_LOAD) {
/* Generic codec initialisation */
ci->configure(DSP_SET_SAMPLE_DEPTH, APE_OUTPUT_DEPTH-1);
}
return CODEC_OK;
}
/* this is called for each file to process */
enum codec_status codec_run(void)
{
struct ape_ctx_t ape_ctx;
uint32_t samplesdone;
uint32_t elapsedtime;
size_t bytesleft;
uint32_t currentframe;
uint32_t newfilepos;
uint32_t samplestoskip;
int nblocks;
int bytesconsumed;
unsigned char* inbuffer;
uint32_t blockstodecode;
int res;
int firstbyte;
size_t resume_offset;
enum codec_command_action action;
intptr_t param;
if (codec_init()) {
LOGF("APE: Error initialising codec\n");
return CODEC_ERROR;
}
action = CODEC_ACTION_NULL;
param = 0;
/* Remember the resume position - when the codec is opened, the
playback engine will reset it. */
elapsedtime = ci->id3->elapsed;
resume_offset = ci->id3->offset;
ci->seek_buffer(0);
inbuffer = ci->request_buffer(&bytesleft, INPUT_CHUNKSIZE);
/* Read the file headers to populate the ape_ctx struct */
if (ape_parseheaderbuf(inbuffer,&ape_ctx) < 0) {
LOGF("APE: Error reading header\n");
return CODEC_ERROR;
}
/* Initialise the seektable for this file */
ape_ctx.seektable = seektablebuf;
ape_ctx.numseekpoints = MIN(MAX_SEEKPOINTS,ape_ctx.numseekpoints);
ci->advance_buffer(ape_ctx.seektablefilepos);
/* The seektable may be bigger than the guard buffer (32KB), so we
do a read() */
ci->read_filebuf(ape_ctx.seektable, ape_ctx.numseekpoints * sizeof(uint32_t));
#ifdef ROCKBOX_BIG_ENDIAN
/* Byte-swap the little-endian seekpoints */
{
uint32_t i;
for(i = 0; i < ape_ctx.numseekpoints; i++)
ape_ctx.seektable[i] = swap32(ape_ctx.seektable[i]);
}
#endif
/* Now advance the file position to the first frame */
ci->advance_buffer(ape_ctx.firstframe -
(ape_ctx.seektablefilepos +
ape_ctx.numseekpoints * sizeof(uint32_t)));
ci->configure(DSP_SET_FREQUENCY, ape_ctx.samplerate);
ci->configure(DSP_SET_STEREO_MODE, ape_ctx.channels == 1 ?
STEREO_MONO : STEREO_NONINTERLEAVED);
codec_set_replaygain(ci->id3);
/* The main decoding loop */
if (resume_offset) {
/* The resume offset is a value in bytes - we need to
turn it into a frame number and samplestoskip value */
ape_resume(&ape_ctx, resume_offset,
&currentframe, &samplesdone, &samplestoskip, &firstbyte);
elapsedtime = (samplesdone*10)/(ape_ctx.samplerate/100);
}
else {
currentframe = 0;
samplesdone = 0;
samplestoskip = 0;
firstbyte = 3; /* Take account of the little-endian 32-bit byte ordering */
if (elapsedtime) {
/* Resume by simulated seeking */
param = elapsedtime;
action = CODEC_ACTION_SEEK_TIME;
}
}
ci->set_elapsed(elapsedtime);
/* Initialise the buffer */
inbuffer = ci->request_buffer(&bytesleft, INPUT_CHUNKSIZE);
/* The main decoding loop - we decode the frames a small chunk at a time */
while (currentframe < ape_ctx.totalframes)
{
frame_start:
/* Calculate how many blocks there are in this frame */
if (currentframe == (ape_ctx.totalframes - 1))
nblocks = ape_ctx.finalframeblocks;
else
nblocks = ape_ctx.blocksperframe;
ape_ctx.currentframeblocks = nblocks;
/* Initialise the frame decoder */
init_frame_decoder(&ape_ctx, inbuffer, &firstbyte, &bytesconsumed);
ci->advance_buffer(bytesconsumed);
inbuffer = ci->request_buffer(&bytesleft, INPUT_CHUNKSIZE);
/* Decode the frame a chunk at a time */
while (nblocks > 0)
{
if (action == CODEC_ACTION_NULL)
action = ci->get_command(&param);
if (action != CODEC_ACTION_NULL) {
if (action == CODEC_ACTION_HALT)
goto done;
/* Deal with any pending seek requests */
if (action == CODEC_ACTION_SEEK_TIME)
{
if (ape_calc_seekpos(&ape_ctx,
(param/10) * (ci->id3->frequency/100),
&currentframe,
&newfilepos,
&samplestoskip))
{
samplesdone = currentframe * ape_ctx.blocksperframe;
/* APE's bytestream is weird... */
firstbyte = 3 - (newfilepos & 3);
newfilepos &= ~3;
ci->seek_buffer(newfilepos);
inbuffer = ci->request_buffer(&bytesleft,
INPUT_CHUNKSIZE);
elapsedtime = (samplesdone*10)/
(ape_ctx.samplerate/100);
ci->set_elapsed(elapsedtime);
ci->seek_complete();
action = CODEC_ACTION_NULL;
goto frame_start; /* Sorry... */
}
ci->seek_complete();
}
action = CODEC_ACTION_NULL;
}
blockstodecode = MIN(BLOCKS_PER_LOOP, nblocks);
if ((res = decode_chunk(&ape_ctx, inbuffer, &firstbyte,
&bytesconsumed,
decoded0, decoded1,
blockstodecode)) < 0)
{
/* Frame decoding error, abort */
LOGF("APE: Frame %lu, error %d\n",(unsigned long)currentframe,res);
return CODEC_ERROR;
}
ci->yield();
if (samplestoskip > 0) {
if (samplestoskip < blockstodecode) {
ci->pcmbuf_insert(decoded0 + samplestoskip,
decoded1 + samplestoskip,
blockstodecode - samplestoskip);
samplestoskip = 0;
} else {
samplestoskip -= blockstodecode;
}
} else {
ci->pcmbuf_insert(decoded0, decoded1, blockstodecode);
}
samplesdone += blockstodecode;
if (!samplestoskip) {
/* Update the elapsed-time indicator */
elapsedtime = (samplesdone*10)/(ape_ctx.samplerate/100);
ci->set_elapsed(elapsedtime);
}
ci->advance_buffer(bytesconsumed);
inbuffer = ci->request_buffer(&bytesleft, INPUT_CHUNKSIZE);
/* Decrement the block count */
nblocks -= blockstodecode;
}
currentframe++;
}
done:
LOGF("APE: Decoded %lu samples\n",(unsigned long)samplesdone);
return CODEC_OK;
}