rockbox/lib/rbcodec/codecs/aac.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

308 lines
10 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 "libm4a/m4a.h"
#include "libfaad/common.h"
#include "libfaad/structs.h"
#include "libfaad/decoder.h"
CODEC_HEADER
/* The maximum buffer size handled by faad. 12 bytes are required by libfaad
* as headroom (see libfaad/bits.c). FAAD_BYTE_BUFFER_SIZE bytes are buffered
* for each frame. */
#define FAAD_BYTE_BUFFER_SIZE (2048-12)
/* 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_STEREO_MODE, STEREO_NONINTERLEAVED);
ci->configure(DSP_SET_SAMPLE_DEPTH, 29);
}
return CODEC_OK;
}
/* this is called for each file to process */
enum codec_status codec_run(void)
{
/* Note that when dealing with QuickTime/MPEG4 files, terminology is
* a bit confusing. Files with sound are split up in chunks, where
* each chunk contains one or more samples. Each sample in turn
* contains a number of "sound samples" (the kind you refer to with
* the sampling frequency).
*/
size_t n;
demux_res_t demux_res;
stream_t input_stream;
uint32_t sound_samples_done;
uint32_t elapsed_time;
int file_offset;
int framelength;
int lead_trim = 0;
unsigned int frame_samples;
unsigned int i;
unsigned char* buffer;
NeAACDecFrameInfo frame_info;
NeAACDecHandle decoder;
int err;
uint32_t seek_idx = 0;
uint32_t s = 0;
uint32_t sbr_fac = 1;
unsigned char c = 0;
void *ret;
enum codec_command_action action;
intptr_t param;
bool empty_first_frame = false;
/* Clean and initialize decoder structures */
memset(&demux_res , 0, sizeof(demux_res));
if (codec_init()) {
LOGF("FAAD: Codec init error\n");
return CODEC_ERROR;
}
action = CODEC_ACTION_NULL;
param = ci->id3->elapsed;
file_offset = ci->id3->offset;
ci->configure(DSP_SET_FREQUENCY, ci->id3->frequency);
codec_set_replaygain(ci->id3);
stream_create(&input_stream,ci);
ci->seek_buffer(ci->id3->first_frame_offset);
/* if qtmovie_read returns successfully, the stream is up to
* the movie data, which can be used directly by the decoder */
if (!qtmovie_read(&input_stream, &demux_res)) {
LOGF("FAAD: File init error\n");
return CODEC_ERROR;
}
/* initialise the sound converter */
decoder = NeAACDecOpen();
if (!decoder) {
LOGF("FAAD: Decode open error\n");
return CODEC_ERROR;
}
NeAACDecConfigurationPtr conf = NeAACDecGetCurrentConfiguration(decoder);
conf->outputFormat = FAAD_FMT_24BIT; /* irrelevant, we don't convert */
NeAACDecSetConfiguration(decoder, conf);
err = NeAACDecInit2(decoder, demux_res.codecdata, demux_res.codecdata_len, &s, &c);
if (err) {
LOGF("FAAD: DecInit: %d, %d\n", err, decoder->object_type);
return CODEC_ERROR;
}
#ifdef SBR_DEC
/* Check for need of special handling for seek/resume and elapsed time. */
if (ci->id3->needs_upsampling_correction) {
sbr_fac = 2;
} else {
sbr_fac = 1;
}
#endif
i = 0;
if (file_offset > 0) {
/* Resume the desired (byte) position. Important: When resuming SBR
* upsampling files the resulting sound_samples_done must be expanded
* by a factor of 2. This is done via using sbr_fac. */
if (m4a_seek_raw(&demux_res, &input_stream, file_offset,
&sound_samples_done, (int*) &i)) {
sound_samples_done *= sbr_fac;
} else {
sound_samples_done = 0;
}
NeAACDecPostSeekReset(decoder, i);
elapsed_time = (sound_samples_done * 10) /
(ci->id3->frequency / 100);
} else if (param) {
elapsed_time = param;
action = CODEC_ACTION_SEEK_TIME;
} else {
elapsed_time = 0;
sound_samples_done = 0;
}
ci->set_elapsed(elapsed_time);
if (i == 0)
{
lead_trim = ci->id3->lead_trim;
}
/* The main decoding loop */
while (i < demux_res.num_sample_byte_sizes) {
if (action == CODEC_ACTION_NULL)
action = ci->get_command(&param);
if (action == CODEC_ACTION_HALT)
break;
/* Deal with any pending seek requests */
if (action == CODEC_ACTION_SEEK_TIME) {
/* Seek to the desired time position. Important: When seeking in SBR
* upsampling files the seek_time must be divided by 2 when calling
* m4a_seek and the resulting sound_samples_done must be expanded
* by a factor 2. This is done via using sbr_fac. */
if (m4a_seek(&demux_res, &input_stream,
(param/10/sbr_fac)*(ci->id3->frequency/100),
&sound_samples_done, (int*) &i)) {
sound_samples_done *= sbr_fac;
elapsed_time = (sound_samples_done * 10) / (ci->id3->frequency / 100);
ci->set_elapsed(elapsed_time);
seek_idx = 0;
if (i == 0)
{
lead_trim = ci->id3->lead_trim;
}
}
NeAACDecPostSeekReset(decoder, i);
ci->seek_complete();
}
action = CODEC_ACTION_NULL;
/* There can be gaps between chunks, so skip ahead if needed. It
* doesn't seem to happen much, but it probably means that a
* "proper" file can have chunks out of order. Why one would want
* that an good question (but files with gaps do exist, so who
* knows?), so we don't support that - for now, at least.
*/
file_offset = m4a_check_sample_offset(&demux_res, i, &seek_idx);
if (file_offset > ci->curpos)
{
ci->advance_buffer(file_offset - ci->curpos);
}
else if (file_offset == 0)
{
LOGF("AAC: get_sample_offset error\n");
return CODEC_ERROR;
}
/* Request the required number of bytes from the input buffer */
buffer=ci->request_buffer(&n, FAAD_BYTE_BUFFER_SIZE);
/* Decode one block - returned samples will be host-endian */
ret = NeAACDecDecode(decoder, &frame_info, buffer, n);
/* NeAACDecDecode may sometimes return NULL without setting error. */
if (ret == NULL || frame_info.error > 0) {
LOGF("FAAD: decode error '%s'\n", NeAACDecGetErrorMessage(frame_info.error));
return CODEC_ERROR;
}
/* Advance codec buffer (no need to call set_offset because of this) */
ci->advance_buffer(frame_info.bytesconsumed);
/* Output the audio */
ci->yield();
frame_samples = frame_info.samples >> 1;
if (empty_first_frame)
{
/* Remove the first frame from lead_trim, under the assumption
* that it had the same size as this frame
*/
empty_first_frame = false;
lead_trim -= frame_samples;
if (lead_trim < 0)
{
lead_trim = 0;
}
}
/* Gather number of samples for the decoded frame. */
framelength = frame_samples - lead_trim;
if (i == demux_res.num_sample_byte_sizes - 1)
{
// Size of the last frame
const uint32_t sample_duration = (demux_res.num_time_to_samples > 0) ?
demux_res.time_to_sample[demux_res.num_time_to_samples - 1].sample_duration :
frame_samples;
/* Currently limited to at most one frame of tail_trim.
* Seems to be enough.
*/
if (ci->id3->tail_trim == 0 && sample_duration < frame_samples)
{
/* Subtract lead_trim just in case we decode a file with only
* one audio frame with actual data (lead_trim is usually zero
* here).
*/
framelength = sample_duration - lead_trim;
}
else
{
framelength -= ci->id3->tail_trim;
}
}
if (framelength > 0)
{
ci->pcmbuf_insert(&decoder->time_out[0][lead_trim],
&decoder->time_out[1][lead_trim],
framelength);
sound_samples_done += framelength;
/* Update the elapsed-time indicator */
elapsed_time = ((uint64_t) sound_samples_done * 1000) /
ci->id3->frequency;
ci->set_elapsed(elapsed_time);
}
if (lead_trim > 0)
{
/* frame_info.samples can be 0 for frame 0. We still want to
* remove it from lead_trim, so do that during frame 1.
*/
if (0 == i && 0 == frame_info.samples)
{
empty_first_frame = true;
}
lead_trim -= frame_samples;
if (lead_trim < 0)
{
lead_trim = 0;
}
}
++i;
}
LOGF("AAC: Decoded %lu samples\n", (unsigned long)sound_samples_done);
return CODEC_OK;
}