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Interolate excitation signal

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Vladimir Voroshilov 2009-06-05 02:12:31 +07:00 committed by Michael Niedermayer
parent 0a3337883f
commit f830d1b7da
1 changed files with 22 additions and 2 deletions
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24
libavcodec/g729dec.c
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@ -95,6 +95,10 @@ typedef struct {
typedef struct {
DSPContext dsp;
/// past excitation signal buffer
int16_t exc_base[2*SUBFRAME_SIZE+PITCH_DELAY_MAX+INTERPOL_LEN];
int16_t* exc; ///< start of past excitation data in buffer
int pitch_delay_int_prev; ///< integer part of previous subframe's pitch delay (4.1.3)
/// (2.13) LSP quantizer outputs
@ -113,6 +117,7 @@ typedef struct {
/// (14.1) gain code from previous subframe
int16_t gain_code;
int16_t was_periodic; ///< whether previous frame was declared as periodic or not (4.4)
uint16_t rand_value; ///< random number generator value (4.4.4)
int ma_predictor_prev; ///< switched MA predictor of LSP quantizer from last good frame
} G729Context;
@ -241,6 +246,8 @@ static av_cold int decoder_init(AVCodecContext * avctx)
ctx->lsp[1] = ctx->lsp_buf[1];
memcpy(ctx->lsp[0], lsp_init, 10 * sizeof(int16_t));
ctx->exc = &ctx->exc_base[PITCH_DELAY_MAX+INTERPOL_LEN];
/* random seed initialization */
ctx->rand_value = 21845;
@ -276,6 +283,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
int pitch_delay_int; // pitch delay, integer part
int pitch_delay_3x; // pitch delay, multiplied by 3
int16_t fc[SUBFRAME_SIZE]; // fixed-codebook vector
int is_periodic = 0; // whether one of the subframes is declared as periodic or not
if (*data_size < SUBFRAME_SIZE << 2) {
av_log(avctx, AV_LOG_ERROR, "Error processing packet: output buffer too small\n");
@ -422,10 +430,17 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
}
ff_acelp_update_past_gain(ctx->quant_energy, gain_corr_factor, 2, frame_erasure);
/* Routine requires rounding to lowest. */
ff_acelp_interpolate(ctx->exc + i * SUBFRAME_SIZE,
ctx->exc + i * SUBFRAME_SIZE - pitch_delay_3x / 3,
ff_acelp_interp_filter, 6,
(pitch_delay_3x % 3) << 1,
10, SUBFRAME_SIZE);
ff_acelp_weighted_vector_sum(ctx->exc + i * SUBFRAME_SIZE,
ctx->exc + i * SUBFRAME_SIZE, fc,
(!voicing && frame_erasure) ? 0 : ctx->gain_pitch,
( voicing && frame_erasure) ? 0 : ctx->gain_code,
(!ctx->was_periodic && frame_erasure) ? 0 : ctx->gain_pitch,
( ctx->was_periodic && frame_erasure) ? 0 : ctx->gain_code,
1 << 13, 14, SUBFRAME_SIZE);
if (frame_erasure)
@ -434,6 +449,11 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
ctx->pitch_delay_int_prev = pitch_delay_int;
}
ctx->was_periodic = is_periodic;
/* Save signal for use in next frame. */
memmove(ctx->exc_base, ctx->exc_base + 2 * SUBFRAME_SIZE, (PITCH_DELAY_MAX+INTERPOL_LEN)*sizeof(int16_t));
*data_size = SUBFRAME_SIZE << 2;
return buf_size;
}