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Better behaved buffering.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15494 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Adam Gashlin 2007-11-06 16:29:28 +00:00
parent 55398e934c
commit b848c683d6
1 changed files with 54 additions and 52 deletions
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100
apps/codecs/adx.c
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@ -6,7 +6,7 @@
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
*
* Copyright (C) 2006 Adam Gashlin (hcs)
* Copyright (C) 2006-2007 Adam Gashlin (hcs)
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
@ -15,7 +15,6 @@
* KIND, either express or implied.
*
****************************************************************************/
#include "codeclib.h"
#include "inttypes.h"
@ -42,7 +41,7 @@ enum codec_status codec_main(void)
int sampleswritten, i;
uint8_t *buf;
int32_t ch1_1, ch1_2, ch2_1, ch2_2; /* ADPCM history */
size_t n, bufsize;
size_t n;
int endofstream; /* end of stream flag */
uint32_t avgbytespersec;
int looping; /* looping flag */
@ -72,17 +71,15 @@ next_track:
codec_set_replaygain(ci->id3);
/* Read the entire file (or as much as possible) */
/* Get header */
DEBUGF("ADX: request initial buffer\n");
ci->configure(CODEC_SET_FILEBUF_WATERMARK, ci->filesize);
ci->seek_buffer(0);
buf = ci->request_buffer(&n, ci->filesize);
buf = ci->request_buffer(&n, 0x38);
if (!buf || n < 0x38) {
return CODEC_ERROR;
}
bufsize = n;
bufoff = 0;
DEBUGF("ADX: read size = %lx\n",(unsigned long)bufsize);
DEBUGF("ADX: read size = %lx\n",(unsigned long)n);
/* Get file header for starting offset, channel count */
@ -151,10 +148,13 @@ next_track:
}
/* advance to first frame */
/*ci->seek_buffer(chanstart);*/
DEBUGF("ADX: first frame at %lx\n",chanstart);
bufoff = chanstart;
/* get in position */
ci->seek_buffer(bufoff);
/* setup pcm buffer format */
ci->configure(DSP_SWITCH_FREQUENCY, ci->id3->frequency);
if (channels == 2) {
@ -180,7 +180,7 @@ next_track:
}
/* do we need to loop? */
if (bufoff >= end_adr-18*channels && looping) {
if (bufoff > end_adr-18*channels && looping) {
DEBUGF("ADX: loop!\n");
/* check for endless looping */
if (ci->global_settings->repeat_mode==REPEAT_ONE) {
@ -198,6 +198,7 @@ next_track:
}
}
bufoff = start_adr;
ci->seek_buffer(bufoff);
}
/* do we need to seek? */
@ -218,55 +219,40 @@ next_track:
bufoff-=end_adr-start_adr;
loop_count++;
}
ci->seek_buffer(bufoff);
ci->seek_complete();
}
if (bufoff>ci->filesize-channels*18) break; /* End of stream */
/* dance with the devil in the pale moonlight */
if ((bufoff > ci->curpos + (off_t)bufsize - channels*18) ||
bufoff < ci->curpos) {
DEBUGF("ADX: requesting another buffer at %lx size %lx\n",
bufoff,ci->filesize-bufoff);
ci->seek_buffer(bufoff);
buf = ci->request_buffer(&n, ci->filesize-bufoff);
bufsize = n;
DEBUGF("ADX: read size = %lx\n",(unsigned long)bufsize);
if ((off_t)bufsize < channels*18) {
/* if we can't get a full frame, just request a single
frame (should be able to fit it in the guard buffer) */
DEBUGF("ADX: requesting single frame at %lx\n",bufoff);
buf = ci->request_buffer(&n, channels*18);
bufsize=n;
DEBUGF("ADX: read size = %lx\n",(unsigned long)bufsize);
}
if (!buf) {
DEBUGF("ADX: couldn't get buffer at %lx size %lx\n",
bufoff,ci->filesize-bufoff);
return CODEC_ERROR;
}
buf-=bufoff;
}
if (bufsize == 0) break; /* End of stream */
sampleswritten=0;
while (
/* Is there data in the file buffer? */
((size_t)bufoff <= ci->curpos+bufsize-(18*channels)) &&
/* Is there data left in the file? */
(bufoff <= ci->filesize-(18*channels)) &&
/* Is there space in the output buffer? */
(sampleswritten <= WAV_CHUNK_SIZE-(32*channels)) &&
/* Should we be looping? */
((!looping) || bufoff < end_adr-18*channels)) {
/* decode 18 bytes to 32 samples (from bero) */
int32_t scale = ((buf[bufoff] << 8) | (buf[bufoff+1])) * BASE_VOL;
((!looping) || bufoff <= end_adr-18*channels))
{
/* decode first/only channel */
int32_t scale;
int32_t ch1_0, d;
/* fetch a frame */
buf = ci->request_buffer(&n, 18);
if (!buf || n!=18) {
DEBUGF("ADX: couldn't get buffer at %lx\n",
bufoff);
return CODEC_ERROR;
}
scale = (((buf[0] << 8) | (buf[1])) +1) * BASE_VOL;
for (i = 2; i < 18; i++)
{
d = (buf[bufoff+i] >> 4) & 15;
d = (buf[i] >> 4) & 15;
if (d & 8) d-= 16;
ch1_0 = (d*scale + 0x7298L*ch1_1 - 0x3350L*ch1_2) >> 14;
if (ch1_0 > 32767) ch1_0 = 32767;
@ -274,7 +260,8 @@ next_track:
samples[sampleswritten] = ch1_0;
sampleswritten+=channels;
ch1_2 = ch1_1; ch1_1 = ch1_0;
d = buf[bufoff+i] & 15;
d = buf[i] & 15;
if (d & 8) d -= 16;
ch1_0 = (d*scale + 0x7298L*ch1_1 - 0x3350L*ch1_2) >> 14;
if (ch1_0 > 32767) ch1_0 = 32767;
@ -284,16 +271,28 @@ next_track:
ch1_2 = ch1_1; ch1_1 = ch1_0;
}
bufoff+=18;
ci->advance_buffer(18);
if (channels == 2) {
int32_t scale = ((buf[bufoff] << 8)|(buf[bufoff+1]))*BASE_VOL;
/* decode second channel */
int32_t scale;
int32_t ch2_0, d;
buf = ci->request_buffer(&n, 18);
if (!buf || n!=18) {
DEBUGF("ADX: couldn't get buffer at %lx\n",
bufoff);
return CODEC_ERROR;
}
scale = (((buf[0] << 8)|(buf[1]))+1)*BASE_VOL;
sampleswritten-=63;
for (i = 2; i < 18; i++)
{
d = (buf[bufoff+i] >> 4) & 15;
d = (buf[i] >> 4) & 15;
if (d & 8) d-= 16;
ch2_0 = (d*scale + 0x7298L*ch2_1 - 0x3350L*ch2_2) >> 14;
if (ch2_0 > 32767) ch2_0 = 32767;
@ -301,7 +300,8 @@ next_track:
samples[sampleswritten] = ch2_0;
sampleswritten+=2;
ch2_2 = ch2_1; ch2_1 = ch2_0;
d = buf[bufoff+i] & 15;
d = buf[i] & 15;
if (d & 8) d -= 16;
ch2_0 = (d*scale + 0x7298L*ch2_1 - 0x3350L*ch2_2) >> 14;
if (ch2_0 > 32767) ch2_0 = 32767;
@ -311,8 +311,10 @@ next_track:
ch2_2 = ch2_1; ch2_1 = ch2_0;
}
bufoff+=18;
ci->advance_buffer(18);
sampleswritten--; /* go back to first channel's next sample */
}
if (fade_count>0) {
fade_count--;
for (i=0;i<(channels==1?32:64);i++) samples[sampleswritten-i-1]=