diff --git a/libavcodec/g729data.h b/libavcodec/g729data.h index 1d64553f20..02d0b938af 100644 --- a/libavcodec/g729data.h +++ b/libavcodec/g729data.h @@ -268,6 +268,11 @@ static const int16_t cb_ma_predictor_sum[2][10] = { /* (0.15) */ {14585, 18333, 19772, 17344, 16426, 16459, 15155, 15220, 16043, 15708} }; +static const int16_t cb_ma_predictor_sum_inv[2][10] = { /* (3.12) */ + {17210, 15888, 16357, 16183, 16516, 15833, 15888, 15421, 14840, 15597}, + { 9202, 7320, 6788, 7738, 8170, 8154, 8856, 8818, 8366, 8544} +}; + /** * initial LSP coefficients belongs to virtual frame preceding the * first frame of the stream diff --git a/libavcodec/g729dec.c b/libavcodec/g729dec.c index 28dbad5903..08ce3a7212 100644 --- a/libavcodec/g729dec.c +++ b/libavcodec/g729dec.c @@ -90,6 +90,8 @@ typedef struct { int16_t lsfq[10]; ///< (2.13) quantized LSF coefficients from previous frame int16_t lsp_buf[2][10]; ///< (0.15) LSP coefficients (previous and current frames) (3.2.5) int16_t *lsp[2]; ///< pointers to lsp_buf + + int ma_predictor_prev; ///< switched MA predictor of LSP quantizer from last good frame } G729Context; static const G729FormatDescription format_g729_8k = { @@ -157,13 +159,26 @@ static void lsf_decode(int16_t* lsfq, int16_t* past_quantizer_outputs[MA_NP + 1] lsfq[i] = sum >> 15; } - /* Rotate past_quantizer_outputs. */ - memmove(past_quantizer_outputs + 1, past_quantizer_outputs, MA_NP * sizeof(int16_t*)); - past_quantizer_outputs[0] = quantizer_output; - ff_acelp_reorder_lsf(lsfq, LSFQ_DIFF_MIN, LSFQ_MIN, LSFQ_MAX, 10); } +static void lsf_restore_from_previous(int16_t* lsfq, + int16_t* past_quantizer_outputs[MA_NP + 1], + int ma_predictor_prev) +{ + int16_t* quantizer_output = past_quantizer_outputs[MA_NP]; + int i,k; + + for (i = 0; i < 10; i++) { + int tmp = lsfq[i] << 15; + + for (k = 0; k < MA_NP; k++) + tmp -= past_quantizer_outputs[k][i] * cb_ma_predictor[ma_predictor_prev][k][i]; + + quantizer_output[i] = ((tmp >> 15) * cb_ma_predictor_sum_inv[ma_predictor_prev][i]) >> 12; + } +} + static av_cold int decoder_init(AVCodecContext * avctx) { G729Context* ctx = avctx->priv_data; @@ -201,6 +216,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, int frame_erasure = 0; ///< frame erasure detected during decoding int bad_pitch = 0; ///< parity check failed int i; + int16_t *tmp; G729Context *ctx = avctx->priv_data; int16_t lp[2][11]; // (3.12) uint8_t ma_predictor; ///< switched MA predictor of LSP quantizer @@ -238,9 +254,20 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, quantizer_2nd_lo = get_bits(&gb, VQ_2ND_BITS); quantizer_2nd_hi = get_bits(&gb, VQ_2ND_BITS); + if(frame_erasure) + lsf_restore_from_previous(ctx->lsfq, ctx->past_quantizer_outputs, + ctx->ma_predictor_prev); + else { lsf_decode(ctx->lsfq, ctx->past_quantizer_outputs, ma_predictor, quantizer_1st, quantizer_2nd_lo, quantizer_2nd_hi); + ctx->ma_predictor_prev = ma_predictor; + } + + tmp = ctx->past_quantizer_outputs[MA_NP]; + memmove(ctx->past_quantizer_outputs + 1, ctx->past_quantizer_outputs, + MA_NP * sizeof(int16_t*)); + ctx->past_quantizer_outputs[0] = tmp; ff_acelp_lsf2lsp(ctx->lsp[1], ctx->lsfq, 10);