[FFmpeg-cvslog] r9670 - trunk/libavcodec/ac3dec.c
jbr
subversion
Sat Jul 14 18:04:40 CEST 2007
Author: jbr
Date: Sat Jul 14 18:04:40 2007
New Revision: 9670
Log:
AC-3 decoder, soc revision 72, Sep 7 04:20:00 2006 UTC by cloud9
fix short block imdct.
Modified:
trunk/libavcodec/ac3dec.c
Modified: trunk/libavcodec/ac3dec.c
==============================================================================
--- trunk/libavcodec/ac3dec.c (original)
+++ trunk/libavcodec/ac3dec.c Sat Jul 14 18:04:40 2007
@@ -1609,7 +1609,8 @@ static void do_imdct_256(AC3DecodeContex
{
int k;
float x1[128], x2[128];
- float *ptr;
+ float *o_ptr, *d_ptr, *w;
+ FFTComplex *ptr1, *ptr2;
for (k = 0; k < N / 4; k++) {
x1[k] = ctx->transform_coeffs[chindex][2 * k];
@@ -1619,10 +1620,23 @@ static void do_imdct_256(AC3DecodeContex
ff_imdct_calc(&ctx->imdct_256, ctx->tmp_output, x1, ctx->tmp_imdct);
ff_imdct_calc(&ctx->imdct_256, ctx->tmp_output + 256, x2, ctx->tmp_imdct);
- ptr = ctx->output[chindex];
- ctx->dsp.vector_fmul_add_add(ptr, ctx->tmp_output, ctx->window, ctx->delay[chindex], 384, BLOCK_SIZE, 1);
- ptr = ctx->delay[chindex];
- ctx->dsp.vector_fmul_reverse(ptr, ctx->tmp_output + 256, ctx->window, BLOCK_SIZE);
+ o_ptr = ctx->output[chindex];
+ d_ptr = ctx->delay[chindex];
+ ptr1 = (FFTComplex *)ctx->tmp_output;
+ ptr2 = (FFTComplex *)ctx->tmp_output + 256;
+ w = ctx->window;
+
+ for (k = 0; k < N / 8; k++)
+ {
+ o_ptr[2 * k] = -ptr1[k].im * w[2 * k] + d_ptr[2 * k] + 384.0;
+ o_ptr[2 * k + 1] = ptr1[N / 8 - k - 1].re * w[2 * k + 1] + 384.0;
+ o_ptr[N / 4 + 2 * k] = -ptr1[k].re * w[N / 4 + 2 * k] + d_ptr[N / 4 + 2 * k] + 384.0;
+ o_ptr[N / 4 + 2 * k + 1] = ptr1[N / 8 - k - 1].im * w[N / 4 + 2 * k + 1] + d_ptr[N / 4 + 2 * k + 1] + 384.0;
+ d_ptr[2 * k] = ptr2[k].re * w[k / 2 - 2 * k - 1];
+ d_ptr[2 * k + 1] = -ptr2[N / 8 - k - 1].im * w[N / 2 - 2 * k - 2];
+ d_ptr[N / 4 + 2 * k] = ptr2[k].im * w[N / 4 - 2 * k - 1];
+ d_ptr[N / 4 + 2 * k + 1] = -ptr2[N / 8 - k - 1].re * w[N / 4 - 2 * k - 2];
+ }
}
/* This function performs the imdct on 512 sample transform
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