-// Some mp3 related code for Sega/Mega CD.
-// Uses the Helix Fixed-point MP3 decoder
-
-// (c) Copyright 2007, Grazvydas "notaz" Ignotas
+/*
+ * Some mp3 related code for Sega/Mega CD.
+ * Uses the Helix Fixed-point MP3 decoder
+ * (C) notaz, 2007-2009
+ *
+ * This work is licensed under the terms of MAME license.
+ * See COPYING file in the top-level directory.
+ */
#include <stdio.h>
#include <string.h>
-#include "../../pico/pico_int.h"
-#include "../../pico/sound/mix.h"
+#include <pico/pico_int.h>
+#include <pico/sound/mix.h>
#include "helix/pub/mp3dec.h"
+#include "mp3.h"
#include "lprintf.h"
-static HMP3Decoder mp3dec = 0;
-static int mp3_buffer_offs = 0;
-
-
-static int find_sync_word(unsigned char *buf, int nBytes)
-{
- unsigned char *p, *pe;
-
- /* find byte-aligned syncword - need 12 (MPEG 1,2) or 11 (MPEG 2.5) matching bits */
- for (p = buf, pe = buf + nBytes - 4; p < pe; p++)
- {
- int pn;
- if (p[0] != 0xff) continue;
- pn = p[1];
- if ((pn & 0xf8) != 0xf8 || // currently must be MPEG1
- (pn & 6) == 0) { // invalid layer
- p++; continue;
- }
- pn = p[2];
- if ((pn & 0xf0) < 0x20 || (pn & 0xf0) == 0xf0 || // bitrates
- (pn & 0x0c) != 0) { // not 44kHz
- continue;
- }
-
- return p - buf;
- }
-
- return -1;
-}
-
-
-static int try_get_header(unsigned char *buff, MP3FrameInfo *fi)
-{
- int ret, offs1, offs = 0;
-
- while (1)
- {
- offs1 = find_sync_word(buff + offs, 2048 - offs);
- if (offs1 < 0) return -2;
- offs += offs1;
- if (2048 - offs < 4) return -3;
-
- // printf("trying header %08x\n", *(int *)(buff + offs));
-
- ret = MP3GetNextFrameInfo(mp3dec, fi, buff + offs);
- if (ret == 0 && fi->bitrate != 0) break;
- offs++;
- }
-
- return ret;
-}
-
-int mp3_get_bitrate(FILE *f, int len)
-{
- unsigned char buff[2048];
- MP3FrameInfo fi;
- int ret;
-
- memset(buff, 0, 2048);
-
- if (mp3dec) MP3FreeDecoder(mp3dec);
- mp3dec = MP3InitDecoder();
-
- fseek(f, 0, SEEK_SET);
- ret = fread(buff, 1, 2048, f);
- fseek(f, 0, SEEK_SET);
- if (ret <= 0) return -1;
-
- ret = try_get_header(buff, &fi);
- if (ret != 0 || fi.bitrate == 0) {
- // try to read somewhere around the middle
- fseek(f, len>>1, SEEK_SET);
- fread(buff, 1, 2048, f);
- fseek(f, 0, SEEK_SET);
- ret = try_get_header(buff, &fi);
- }
- if (ret != 0) return ret;
-
- // printf("bitrate: %i\n", fi.bitrate / 1000);
-
- return fi.bitrate / 1000;
-}
-
+static HMP3Decoder mp3dec;
+static unsigned char mp3_input_buffer[2 * 1024];
#ifdef __GP2X__
-
-#include "../gp2x/code940/940shared.h"
-
-extern _940_ctl_t *shared_ctl;
-extern unsigned char *mp3_mem;
-
-static int mp3_decode(void)
-{
- // tried copying this to cached mem, no improvement noticed
- int mp3_offs = shared_ctl->mp3_offs;
- unsigned char *readPtr = mp3_mem + mp3_offs;
- int bytesLeft = shared_ctl->mp3_len - mp3_offs;
- int offset; // frame offset from readPtr
- int retries = 0, err;
-
- if (bytesLeft <= 0) return 1; // EOF, nothing to do
-
-retry:
- offset = find_sync_word(readPtr, bytesLeft);
- if (offset < 0) {
- shared_ctl->mp3_offs = shared_ctl->mp3_len;
- return 1; // EOF
- }
- readPtr += offset;
- bytesLeft -= offset;
-
- err = MP3Decode(mp3dec, &readPtr, &bytesLeft, cdda_out_buffer, 0);
- if (err) {
- if (err == ERR_MP3_INDATA_UNDERFLOW) {
- shared_ctl->mp3_offs = shared_ctl->mp3_len; // EOF
- return 1;
- } else if (err <= -6 && err >= -12) {
- // ERR_MP3_INVALID_FRAMEHEADER, ERR_MP3_INVALID_*
- // just try to skip the offending frame..
- readPtr++;
- bytesLeft--;
- if (retries++ < 2) goto retry;
- else lprintf("mp3 decode failed with %i after %i retries\n", err, retries);
- }
- shared_ctl->mp3_errors++;
- shared_ctl->mp3_lasterr = err;
- }
- shared_ctl->mp3_offs = readPtr - mp3_mem;
- return 0;
-}
-
-void mp3_start_local(void)
-{
- // must re-init decoder for new track
- if (mp3dec) MP3FreeDecoder(mp3dec);
- mp3dec = MP3InitDecoder();
-
- mp3_buffer_offs = 0;
- mp3_decode();
-}
-
#define mp3_update mp3_update_local
+#define mp3_start_play mp3_start_play_local
+#endif
-#else // !__GP2X__
-
-static FILE *mp3_current_file = NULL;
-static int mp3_file_len = 0, mp3_file_pos = 0;
-static unsigned char mp3_input_buffer[2*1024];
-
-static int mp3_decode(void)
+int mp3dec_decode(FILE *f, int *file_pos, int file_len)
{
unsigned char *readPtr;
int bytesLeft;
int offset; // mp3 frame offset from readPtr
- int err;
+ int had_err;
+ int err = 0;
do
{
- if (mp3_file_pos >= mp3_file_len) return 1; // EOF, nothing to do
+ if (*file_pos >= file_len)
+ return 1; /* EOF, nothing to do */
- fseek(mp3_current_file, mp3_file_pos, SEEK_SET);
- bytesLeft = fread(mp3_input_buffer, 1, sizeof(mp3_input_buffer), mp3_current_file);
+ fseek(f, *file_pos, SEEK_SET);
+ bytesLeft = fread(mp3_input_buffer, 1, sizeof(mp3_input_buffer), f);
- offset = find_sync_word(mp3_input_buffer, bytesLeft);
+ offset = mp3_find_sync_word(mp3_input_buffer, bytesLeft);
if (offset < 0) {
- //lprintf("find_sync_word (%i/%i) err %i\n", mp3_file_pos, mp3_file_len, offset);
- mp3_file_pos = mp3_file_len;
+ lprintf("find_sync_word (%i/%i) err %i\n",
+ *file_pos, file_len, offset);
+ *file_pos = file_len;
return 1; // EOF
}
readPtr = mp3_input_buffer + offset;
bytesLeft -= offset;
+ had_err = err;
err = MP3Decode(mp3dec, &readPtr, &bytesLeft, cdda_out_buffer, 0);
if (err) {
- //lprintf("MP3Decode err (%i/%i) %i\n", mp3_file_pos, mp3_file_len, err);
- if (err == ERR_MP3_INDATA_UNDERFLOW) {
+ if (err == ERR_MP3_MAINDATA_UNDERFLOW && !had_err) {
+ // just need another frame
+ *file_pos += readPtr - mp3_input_buffer;
+ continue;
+ }
+ if (err == ERR_MP3_INDATA_UNDERFLOW && !had_err) {
if (offset == 0)
// something's really wrong here, frame had to fit
- mp3_file_pos = mp3_file_len;
+ *file_pos = file_len;
else
- mp3_file_pos += offset;
+ *file_pos += offset;
continue;
- } else if (err <= -6 && err >= -12) {
+ }
+ if (-12 <= err && err <= -6) {
// ERR_MP3_INVALID_FRAMEHEADER, ERR_MP3_INVALID_*
// just try to skip the offending frame..
- mp3_file_pos += offset + 1;
+ *file_pos += offset + 1;
continue;
}
- mp3_file_pos = mp3_file_len;
+ lprintf("MP3Decode err (%i/%i) %i\n",
+ *file_pos, file_len, err);
+ *file_pos = file_len;
return 1;
}
- mp3_file_pos += readPtr - mp3_input_buffer;
+ *file_pos += readPtr - mp3_input_buffer;
}
while (0);
return 0;
}
-void mp3_start_play(FILE *f, int pos)
+int mp3dec_start(FILE *f, int fpos_start)
{
- mp3_file_len = mp3_file_pos = 0;
- mp3_current_file = NULL;
- mp3_buffer_offs = 0;
-
// must re-init decoder for new track
- if (mp3dec) MP3FreeDecoder(mp3dec);
+ if (mp3dec)
+ MP3FreeDecoder(mp3dec);
mp3dec = MP3InitDecoder();
- if (!(PicoOpt&POPT_EN_MCD_CDDA) || f == NULL) // cdda disabled or no file?
- return;
-
- //lprintf("mp3_start_play %p %i\n", f, pos);
-
- mp3_current_file = f;
- fseek(f, 0, SEEK_END);
- mp3_file_len = ftell(f);
-
- // seek..
- if (pos) {
- mp3_file_pos = (mp3_file_len << 6) >> 10;
- mp3_file_pos *= pos;
- mp3_file_pos >>= 6;
- }
-
- mp3_decode();
+ return (mp3dec == 0) ? -1 : 0;
}
-
-int mp3_get_offset(void)
-{
- unsigned int offs1024 = 0;
- int cdda_on;
-
- cdda_on = (PicoAHW & PAHW_MCD) && (PicoOpt&POPT_EN_MCD_CDDA) && !(Pico_mcd->s68k_regs[0x36] & 1) &&
- (Pico_mcd->scd.Status_CDC & 1) && mp3_current_file != NULL;
-
- if (cdda_on) {
- offs1024 = mp3_file_pos << 7;
- offs1024 /= mp3_file_len >> 3;
- }
- //lprintf("mp3_get_offset offs1024=%u (%i/%i)\n", offs1024, mp3_file_pos, mp3_file_len);
-
- return offs1024;
-}
-
-#endif // ifndef __GP2X__
-
-void mp3_update(int *buffer, int length, int stereo)
-{
- int length_mp3, shr = 0;
- void (*mix_samples)(int *dest_buf, short *mp3_buf, int count) = mix_16h_to_32;
-
-#ifndef __GP2X__
- if (mp3_current_file == NULL || mp3_file_pos >= mp3_file_len) return; // no file / EOF
-#endif
-
- length_mp3 = length;
- if (PsndRate == 22050) { mix_samples = mix_16h_to_32_s1; length_mp3 <<= 1; shr = 1; }
- else if (PsndRate == 11025) { mix_samples = mix_16h_to_32_s2; length_mp3 <<= 2; shr = 2; }
-
- if (1152 - mp3_buffer_offs >= length_mp3) {
- mix_samples(buffer, cdda_out_buffer + mp3_buffer_offs*2, length<<1);
-
- mp3_buffer_offs += length_mp3;
- } else {
- int ret, left = 1152 - mp3_buffer_offs;
-
- mix_samples(buffer, cdda_out_buffer + mp3_buffer_offs*2, (left>>shr)<<1);
- ret = mp3_decode();
- if (ret == 0) {
- mp3_buffer_offs = length_mp3 - left;
- mix_samples(buffer + ((left>>shr)<<1), cdda_out_buffer, (mp3_buffer_offs>>shr)<<1);
- } else
- mp3_buffer_offs = 0;
- }
-}
-
-
notaz.gp2x.de / picodrive.git / blobdiff