rockbox/lib/rbcodec/codecs/nsf.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

141 lines
3.6 KiB
C

/* Ripped off from Game_Music_Emu 0.5.2. http://www.slack.net/~ant/ */
#define GME_NSF_TYPE
#include <codecs/lib/codeclib.h>
#include "libgme/nsf_emu.h"
CODEC_HEADER
/* Maximum number of bytes to process in one iteration */
#define CHUNK_SIZE (1024*2)
static int16_t samples[CHUNK_SIZE] IBSS_ATTR;
static struct Nsf_Emu nsf_emu;
/****************** rockbox interface ******************/
static void set_codec_track(int t, int multitrack) {
Nsf_start_track(&nsf_emu, t);
/* for REPEAT_ONE we disable track limits */
if (!ci->loop_track()) {
Track_set_fade(&nsf_emu, Track_length( &nsf_emu, t ) - 4000, 4000);
}
if (multitrack) ci->set_elapsed(t*1000); /* t is track no to display */
else ci->set_elapsed(0);
}
/* this is the codec entry point */
enum codec_status codec_main(enum codec_entry_call_reason reason)
{
if (reason == CODEC_LOAD) {
/* we only render 16 bits */
ci->configure(DSP_SET_SAMPLE_DEPTH, 16);
/* 44 Khz, Interleaved stereo */
ci->configure(DSP_SET_FREQUENCY, 44100);
ci->configure(DSP_SET_STEREO_MODE, STEREO_INTERLEAVED);
Nsf_init(&nsf_emu);
Nsf_set_sample_rate(&nsf_emu, 44100);
}
return CODEC_OK;
}
/* this is called for each file to process */
enum codec_status codec_run(void)
{
blargg_err_t err;
uint8_t *buf;
size_t n;
int track, is_multitrack;
uint32_t elapsed_time;
intptr_t param;
track = is_multitrack = 0;
elapsed_time = 0;
param = ci->id3->elapsed;
DEBUGF("NSF: next_track\n");
if (codec_init()) {
return CODEC_ERROR;
}
codec_set_replaygain(ci->id3);
/* Read the entire file */
DEBUGF("NSF: request file\n");
ci->seek_buffer(0);
buf = ci->request_buffer(&n, ci->filesize);
if (!buf || n < (size_t)ci->filesize) {
DEBUGF("NSF: file load failed\n");
return CODEC_ERROR;
}
if ((err = Nsf_load_mem(&nsf_emu, buf, ci->filesize))) {
DEBUGF("NSF: Nsf_load_mem failed (%s)\n", err);
return CODEC_ERROR;
}
/* Update internal track count */
if (nsf_emu.m3u.size > 0)
nsf_emu.track_count = nsf_emu.m3u.size;
if (nsf_emu.track_count > 1) is_multitrack = 1;
if (param) {
goto resume_start;
}
next_track:
set_codec_track(track, is_multitrack);
/* The main decoder loop */
while (1) {
enum codec_command_action action = ci->get_command(&param);
if (action == CODEC_ACTION_HALT)
break;
if (action == CODEC_ACTION_SEEK_TIME) {
resume_start:
if (is_multitrack) {
track = param/1000;
ci->seek_complete();
if (track >= nsf_emu.track_count) break;
goto next_track;
}
ci->set_elapsed(param);
elapsed_time = param;
Track_seek(&nsf_emu, param);
ci->seek_complete();
/* Set fade again */
if (!ci->loop_track()) {
Track_set_fade(&nsf_emu, Track_length( &nsf_emu, track ), 4000);
}
}
/* Generate audio buffer */
err = Nsf_play(&nsf_emu, CHUNK_SIZE, samples);
if (err || Track_ended(&nsf_emu)) {
track++;
if (track >= nsf_emu.track_count) break;
goto next_track;
}
ci->pcmbuf_insert(samples, NULL, CHUNK_SIZE >> 1);
/* Set elapsed time for one track files */
if (is_multitrack == 0) {
elapsed_time += (CHUNK_SIZE / 2) * 10 / 441;
ci->set_elapsed(elapsed_time);
}
}
return CODEC_OK;
}