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Simplify: use a single history buffer for gain and a single one for 

speech instead of having two for each in the context.

Originally committed as revision 15307 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Vitor Sessak 2008-09-13 16:49:05 +00:00
parent a35acd7f8c
commit 111734de09
1 changed files with 25 additions and 22 deletions
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47
libavcodec/ra288.c
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@ -29,18 +29,21 @@ typedef struct {
float sp_lpc[36]; ///< LPC coefficients for speech data (spec: A)
float gain_lpc[10]; ///< LPC coefficients for gain (spec: GB)
float sp_hist[111]; ///< speech data history (spec: SB)
/** speech data history (spec: SB).
* Its first 70 coefficients are updated only at backward filtering.
*/
float sp_hist[111];
/// speech part of the gain autocorrelation (spec: REXP)
float sp_rec[37];
float gain_hist[38]; ///< log-gain history (spec: SBLG)
/** log-gain history (spec: SBLG).
* Its first 28 coefficients are updated only at backward filtering.
*/
float gain_hist[38];
/// recursive part of the gain autocorrelation (spec: REXPLG)
float gain_rec[11];
float sp_block[41]; ///< four blocks of speech data (spec: STTMP)
float gain_block[10]; ///< four blocks of gain data (spec: GSTATE)
} RA288Context;
static av_cold int ra288_decode_init(AVCodecContext *avctx)
@ -71,9 +74,10 @@ static void decode(RA288Context *ractx, float gain, int cb_coef)
int i, j;
double sumsum;
float sum, buffer[5];
float *block = ractx->sp_block + 36; // current block
float *block = ractx->sp_hist + 70 + 36; // current block
float *gain_block = ractx->gain_hist + 28;
memmove(ractx->sp_block, ractx->sp_block + 5, 36*sizeof(*ractx->sp_block));
memmove(ractx->sp_hist + 70, ractx->sp_hist + 75, 36*sizeof(*block));
for (i=0; i < 5; i++) {
block[i] = 0.;
@ -84,7 +88,7 @@ static void decode(RA288Context *ractx, float gain, int cb_coef)
/* block 46 of G.728 spec */
sum = 32.;
for (i=0; i < 10; i++)
sum -= ractx->gain_block[9-i] * ractx->gain_lpc[i];
sum -= gain_block[9-i] * ractx->gain_lpc[i];
/* block 47 of G.728 spec */
sum = av_clipf(sum, 0, 60);
@ -100,10 +104,9 @@ static void decode(RA288Context *ractx, float gain, int cb_coef)
sum = FFMAX(sum, 1);
/* shift and store */
memmove(ractx->gain_block, ractx->gain_block + 1,
9 * sizeof(*ractx->gain_block));
memmove(gain_block, gain_block + 1, 9 * sizeof(*gain_block));
ractx->gain_block[9] = 10 * log10(sum) - 32;
gain_block[9] = 10 * log10(sum) - 32;
for (i=1; i < 5; i++)
for (j=i-1; j >= 0; j--)
@ -128,14 +131,12 @@ static void convolve(float *tgt, const float *src, int len, int n)
* @param n input length
* @param non_rec number of non-recursive samples
* @param out filter output
* @param in pointer to the input of the filter
* @param hist Pointer to the input history of the filter, it is updated by
* this function.
* @param hist pointer to the input history of the filter
* @param out pointer to the non-recursive part of the output
* @param out2 pointer to the recursive part of the output
* @param window pointer to the windowing function table
*/
static void do_hybrid_window(int order, int n, int non_rec, const float *in,
static void do_hybrid_window(int order, int n, int non_rec,
float *out, float *hist, float *out2,
const float *window)
{
@ -144,10 +145,6 @@ static void do_hybrid_window(int order, int n, int non_rec, const float *in,
float buffer2[order + 1];
float work[order + n + non_rec];
/* update history */
memmove(hist , hist + n, (order + non_rec)*sizeof(*hist));
memcpy (hist + order + non_rec, in , n *sizeof(*hist));
apply_window(work, window, hist, order + n + non_rec);
convolve(buffer1, work + order , n , order);
@ -170,17 +167,23 @@ static void backward_filter(RA288Context *ractx)
float temp1[37]; // RTMP in the spec
float temp2[11]; // GPTPMP in the spec
do_hybrid_window(36, 40, 35, ractx->sp_block+1, temp1, ractx->sp_hist,
do_hybrid_window(36, 40, 35, temp1, ractx->sp_hist,
ractx->sp_rec, syn_window);
if (!compute_lpc_coefs(temp1, 36, ractx->sp_lpc, 0, 1, 1))
apply_window(ractx->sp_lpc, ractx->sp_lpc, syn_bw_tab, 36);
do_hybrid_window(10, 8, 20, ractx->gain_block+2, temp2, ractx->gain_hist,
do_hybrid_window(10, 8, 20, temp2, ractx->gain_hist,
ractx->gain_rec, gain_window);
if (!compute_lpc_coefs(temp2, 10, ractx->gain_lpc, 0, 1, 1))
apply_window(ractx->gain_lpc, ractx->gain_lpc, gain_bw_tab, 10);
memmove(ractx->gain_hist, ractx->gain_hist + 8,
28*sizeof(*ractx->gain_hist));
memmove(ractx->sp_hist , ractx->sp_hist + 40,
70*sizeof(*ractx->sp_hist ));
}
static int ra288_decode_frame(AVCodecContext * avctx, void *data,
@ -211,7 +214,7 @@ static int ra288_decode_frame(AVCodecContext * avctx, void *data,
decode(ractx, gain, cb_coef);
for (j=0; j < 5; j++)
*(out++) = 8 * ractx->sp_block[36 + j];
*(out++) = 8 * ractx->sp_hist[70 + 36 + j];
if ((i & 7) == 3)
backward_filter(ractx);