diff --git a/libavcodec/dca.c b/libavcodec/dca.c index 9359d8fb7e..071042fcd6 100644 --- a/libavcodec/dca.c +++ b/libavcodec/dca.c @@ -159,6 +159,7 @@ typedef struct { float subband_samples_hist[DCA_PRIM_CHANNELS_MAX][DCA_SUBBANDS][4]; float subband_fir_hist[DCA_PRIM_CHANNELS_MAX][512]; float subband_fir_noidea[DCA_PRIM_CHANNELS_MAX][32]; + int hist_index[DCA_PRIM_CHANNELS_MAX]; int output; ///< type of output int bias; ///< output bias @@ -658,7 +659,7 @@ static void qmf_32_subbands(DCAContext * s, int chans, int i, j, k; float praXin[33], *raXin = &praXin[1]; - float *subband_fir_hist = s->subband_fir_hist[chans]; + int hist_index= s->hist_index[chans]; float *subband_fir_hist2 = s->subband_fir_noidea[chans]; int chindex = 0, subindex; @@ -673,6 +674,7 @@ static void qmf_32_subbands(DCAContext * s, int chans, /* Reconstructed channel sample index */ for (subindex = 0; subindex < 8; subindex++) { + float *subband_fir_hist = s->subband_fir_hist[chans] + hist_index; /* Load in one sample from each subband and clear inactive subbands */ for (i = 0; i < s->subband_activity[chans]; i++) raXin[i] = samples_in[i][subindex]; @@ -696,17 +698,21 @@ static void qmf_32_subbands(DCAContext * s, int chans, for (k = 31, i = 0; i < 32; i++, k--){ float a= subband_fir_hist2[i]; float b= 0; - for (j = 0; j < 512; j += 64){ + for (j = 0; j < 512-hist_index; j += 64){ a += prCoeff[i+j ]*( subband_fir_hist[i+j] - subband_fir_hist[j+k]); b += prCoeff[i+j+32]*(-subband_fir_hist[i+j] - subband_fir_hist[j+k]); } + for ( ; j < 512; j += 64){ + a += prCoeff[i+j ]*( subband_fir_hist[i+j-512] - subband_fir_hist[j+k-512]); + b += prCoeff[i+j+32]*(-subband_fir_hist[i+j-512] - subband_fir_hist[j+k-512]); + } samples_out[chindex++] = a * scale + bias; subband_fir_hist2[i] = b; } - /* Update working arrays */ - memmove(&subband_fir_hist[32], &subband_fir_hist[0], (512 - 32) * sizeof(float)); + hist_index = (hist_index-32)&511; } + s->hist_index[chans]= hist_index; } static void lfe_interpolation_fir(int decimation_select,