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Reorganise the wma_decode_superframe() function - split into a separate init and decode functions. Each call to the decode function now decodes a single frame (2048 samples) instead of an entire superframe (which typically contained about 7 or 8 frames and can in theory contain up to 16 frames). This allows us to replace the 256KB output buffer with a 8KB buffer, and also perform more yields in the main decoding loop.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@13833 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Dave Chapman 2007-07-09 17:24:00 +00:00
parent 01e8fce287
commit 88e32c2fc6
3 changed files with 104 additions and 65 deletions
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11
apps/codecs/libwma/wmadec.h
View file

@ -137,6 +137,11 @@ typedef struct WMADecodeContext
fixed64 lsp_pow_m_table1[(1 << LSP_POW_BITS)];
fixed64 lsp_pow_m_table2[(1 << LSP_POW_BITS)];
/* State of current superframe decoding */
int bit_offset;
int nb_frames;
int current_frame;
#ifdef TRACE
int frame_count;
@ -145,7 +150,9 @@ typedef struct WMADecodeContext
WMADecodeContext;
int wma_decode_init(WMADecodeContext* s, asf_waveformatex_t *wfx);
int wma_decode_superframe(WMADecodeContext* s,
void *data, int *data_size,
int wma_decode_superframe_init(WMADecodeContext* s,
uint8_t *buf, int buf_size);
int wma_decode_superframe_frame(WMADecodeContext* s,
int16_t *samples,
uint8_t *buf, int buf_size);
#endif

93
apps/codecs/libwma/wmadeci.c
View file

@ -935,6 +935,9 @@ int wma_decode_init(WMADecodeContext* s, asf_waveformatex_t *wfx)
init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
&coef_vlcs[coef_vlc_table * 2 + 1], 1);
s->last_superframe_len = 0;
s->last_bitoffset = 0;
return 0;
}
@ -1666,42 +1669,67 @@ static int wma_decode_frame(WMADecodeContext *s, int16_t *samples)
return 0;
}
int wma_decode_superframe(WMADecodeContext* s,
void *data, /*output*/
int *data_size,
/* Initialise the superframe decoding */
int wma_decode_superframe_init(WMADecodeContext* s,
uint8_t *buf, /*input*/
int buf_size)
{
//WMADecodeContext *s = avctx->priv_data;
int nb_frames, bit_offset, i, pos, len;
uint8_t *q;
int16_t *samples;
if (buf_size==0)
{
s->last_superframe_len = 0;
return 0;
}
samples = data;
s->current_frame = 0;
init_get_bits(&s->gb, buf, buf_size*8);
if (s->use_bit_reservoir)
{
/* read super frame header */
get_bits(&s->gb, 4); /* super frame index */
nb_frames = get_bits(&s->gb, 4) - 1;
s->nb_frames = get_bits(&s->gb, 4);
bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
if (s->last_superframe_len == 0)
s->nb_frames --;
else if (s->nb_frames == 0)
s->nb_frames++;
s->bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
} else {
s->nb_frames = 1;
}
return 1;
}
/* Decode a single frame in the current superframe - return -1 if
there was a decoding error, or the number of samples decoded.
*/
int wma_decode_superframe_frame(WMADecodeContext* s,
int16_t* samples, /*output*/
uint8_t *buf, /*input*/
int buf_size)
{
int pos, len;
uint8_t *q;
int done = 0;
if ((s->use_bit_reservoir) && (s->current_frame == 0))
{
if (s->last_superframe_len > 0)
{
/* add bit_offset bits to last frame */
if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
/* add s->bit_offset bits to last frame */
if ((s->last_superframe_len + ((s->bit_offset + 7) >> 3)) >
MAX_CODED_SUPERFRAME_SIZE)
{
goto fail;
}
q = s->last_superframe + s->last_superframe_len;
len = bit_offset;
len = s->bit_offset;
while (len > 0)
{
*q++ = (get_bits)(&s->gb, 8);
@ -1712,39 +1740,46 @@ int wma_decode_superframe(WMADecodeContext* s,
*q++ = (get_bits)(&s->gb, len) << (8 - len);
}
/* XXX: bit_offset bits into last frame */
/* XXX: s->bit_offset bits into last frame */
init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8);
/* skip unused bits */
if (s->last_bitoffset > 0)
skip_bits(&s->gb, s->last_bitoffset);
/* this frame is stored in the last superframe and in the
current one */
if (wma_decode_frame(s, samples) < 0)
{
goto fail;
}
samples += s->nb_channels * s->frame_len;
done = 1;
}
/* read each frame starting from bit_offset */
pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
/* read each frame starting from s->bit_offset */
pos = s->bit_offset + 4 + 4 + s->byte_offset_bits + 3;
init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8);
len = pos & 7;
if (len > 0)
skip_bits(&s->gb, len);
s->reset_block_lengths = 1;
for(i=0;i<nb_frames;++i)
}
/* If we haven't decoded a frame yet, do it now */
if (!done)
{
if (wma_decode_frame(s, samples) < 0)
{
goto fail;
}
samples += s->nb_channels * s->frame_len;
}
s->current_frame++;
if ((s->use_bit_reservoir) && (s->current_frame == s->nb_frames))
{
/* we copy the end of the frame in the last frame buffer */
pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
pos = get_bits_count(&s->gb) + ((s->bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
s->last_bitoffset = pos & 7;
pos >>= 3;
len = buf_size - pos;
@ -1755,21 +1790,11 @@ int wma_decode_superframe(WMADecodeContext* s,
s->last_superframe_len = len;
memcpy(s->last_superframe, buf + pos, len);
}
else
{
/* single frame decode */
if (wma_decode_frame(s, samples) < 0)
{
goto fail;
}
samples += s->nb_channels * s->frame_len;
}
*data_size = (int8_t *)samples - (int8_t *)data;
return s->block_align;
return s->frame_len;
fail:
/* when error, we reset the bit reservoir */
s->last_superframe_len = 0;
return -1;
}

41
apps/codecs/wma.c
View file

@ -23,16 +23,15 @@
CODEC_HEADER
#define MAX_BLOCKSIZE 2048
/* The output buffer containing the decoded samples (channels 0 and 1)
BLOCK_MAX_SIZE is 2048 (samples) and MAX_CHANNELS is 2.
*/
/* The output buffers containing the decoded samples (channels 0 and 1) */
static uint16_t decoded[BLOCK_MAX_SIZE * MAX_CHANNELS];
/* NOTE: WMADecodeContext is 142688 bytes (on x86) */
static WMADecodeContext wmadec;
/* TODO: Check the size of this */
#define OUTBUF_SIZE 256*1024
enum asf_error_e {
ASF_ERROR_INTERNAL = -1, /* incorrect input to API calls */
ASF_ERROR_OUTOFMEM = -2, /* some malloc inside program failed */
@ -286,8 +285,8 @@ enum codec_status codec_main(void)
unsigned char* inbuffer;
size_t resume_offset;
size_t n;
int wmares, res, padding, outbufsize;
uint8_t* outbuf;
int i;
int wmares, res, padding;
/* Generic codec initialisation */
ci->configure(CODEC_SET_FILEBUF_WATERMARK, 1024*512);
@ -313,8 +312,6 @@ enum codec_status codec_main(void)
goto exit;
}
outbuf = codec_malloc(OUTBUF_SIZE);
/* Copy the format metadata we've stored in the id3 TOC field. This
saves us from parsing it again here. */
memcpy(&wfx, ci->id3->toc, sizeof(wfx));
@ -355,22 +352,32 @@ enum codec_status codec_main(void)
if (res > 0) {
inbuffer = ci->request_buffer(&n, res - padding);
wmares = wma_decode_superframe(&wmadec,
outbuf,&outbufsize,
wma_decode_superframe_init(&wmadec,
inbuffer,res - padding);
ci->advance_buffer(res);
for (i=0; i < wmadec.nb_frames; i++)
{
wmares = wma_decode_superframe_frame(&wmadec,
decoded,
inbuffer,res - padding);
if (wmares > 0) {
ci->pcmbuf_insert(outbuf, NULL, outbufsize / (wfx.channels * 2));
samplesdone += (outbufsize / (wfx.channels * 2));
DEBUGF("Decoded %d samples\n",(outbufsize / (wfx.channels * 2)));
ci->yield ();
if (wmares < 0)
{
LOGF("WMA decode error %d\n",wmares);
goto done;
} else if (wmares > 0) {
ci->pcmbuf_insert(decoded, NULL, wmares);
samplesdone += wmares;
elapsedtime = (samplesdone*10)/(wfx.rate/100);
ci->set_elapsed(elapsedtime);
}
ci->yield ();
}
ci->advance_buffer(res);
}
}
retval = CODEC_OK;