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-rw-r--r--media/libvpx/vp8/common/idctllm.c205
1 files changed, 205 insertions, 0 deletions
diff --git a/media/libvpx/vp8/common/idctllm.c b/media/libvpx/vp8/common/idctllm.c
new file mode 100644
index 000000000..f5403c5aa
--- /dev/null
+++ b/media/libvpx/vp8/common/idctllm.c
@@ -0,0 +1,205 @@
+/*
+ * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "./vp8_rtcd.h"
+
+/****************************************************************************
+ * Notes:
+ *
+ * This implementation makes use of 16 bit fixed point verio of two multiply
+ * constants:
+ * 1. sqrt(2) * cos (pi/8)
+ * 2. sqrt(2) * sin (pi/8)
+ * Becuase the first constant is bigger than 1, to maintain the same 16 bit
+ * fixed point precision as the second one, we use a trick of
+ * x * a = x + x*(a-1)
+ * so
+ * x * sqrt(2) * cos (pi/8) = x + x * (sqrt(2) *cos(pi/8)-1).
+ **************************************************************************/
+static const int cospi8sqrt2minus1 = 20091;
+static const int sinpi8sqrt2 = 35468;
+
+void vp8_short_idct4x4llm_c(short *input, unsigned char *pred_ptr,
+ int pred_stride, unsigned char *dst_ptr,
+ int dst_stride)
+{
+ int i;
+ int r, c;
+ int a1, b1, c1, d1;
+ short output[16];
+ short *ip = input;
+ short *op = output;
+ int temp1, temp2;
+ int shortpitch = 4;
+
+ for (i = 0; i < 4; i++)
+ {
+ a1 = ip[0] + ip[8];
+ b1 = ip[0] - ip[8];
+
+ temp1 = (ip[4] * sinpi8sqrt2) >> 16;
+ temp2 = ip[12] + ((ip[12] * cospi8sqrt2minus1) >> 16);
+ c1 = temp1 - temp2;
+
+ temp1 = ip[4] + ((ip[4] * cospi8sqrt2minus1) >> 16);
+ temp2 = (ip[12] * sinpi8sqrt2) >> 16;
+ d1 = temp1 + temp2;
+
+ op[shortpitch*0] = a1 + d1;
+ op[shortpitch*3] = a1 - d1;
+
+ op[shortpitch*1] = b1 + c1;
+ op[shortpitch*2] = b1 - c1;
+
+ ip++;
+ op++;
+ }
+
+ ip = output;
+ op = output;
+
+ for (i = 0; i < 4; i++)
+ {
+ a1 = ip[0] + ip[2];
+ b1 = ip[0] - ip[2];
+
+ temp1 = (ip[1] * sinpi8sqrt2) >> 16;
+ temp2 = ip[3] + ((ip[3] * cospi8sqrt2minus1) >> 16);
+ c1 = temp1 - temp2;
+
+ temp1 = ip[1] + ((ip[1] * cospi8sqrt2minus1) >> 16);
+ temp2 = (ip[3] * sinpi8sqrt2) >> 16;
+ d1 = temp1 + temp2;
+
+
+ op[0] = (a1 + d1 + 4) >> 3;
+ op[3] = (a1 - d1 + 4) >> 3;
+
+ op[1] = (b1 + c1 + 4) >> 3;
+ op[2] = (b1 - c1 + 4) >> 3;
+
+ ip += shortpitch;
+ op += shortpitch;
+ }
+
+ ip = output;
+ for (r = 0; r < 4; r++)
+ {
+ for (c = 0; c < 4; c++)
+ {
+ int a = ip[c] + pred_ptr[c] ;
+
+ if (a < 0)
+ a = 0;
+
+ if (a > 255)
+ a = 255;
+
+ dst_ptr[c] = (unsigned char) a ;
+ }
+ ip += 4;
+ dst_ptr += dst_stride;
+ pred_ptr += pred_stride;
+ }
+}
+
+void vp8_dc_only_idct_add_c(short input_dc, unsigned char *pred_ptr,
+ int pred_stride, unsigned char *dst_ptr,
+ int dst_stride)
+{
+ int a1 = ((input_dc + 4) >> 3);
+ int r, c;
+
+ for (r = 0; r < 4; r++)
+ {
+ for (c = 0; c < 4; c++)
+ {
+ int a = a1 + pred_ptr[c] ;
+
+ if (a < 0)
+ a = 0;
+
+ if (a > 255)
+ a = 255;
+
+ dst_ptr[c] = (unsigned char) a ;
+ }
+
+ dst_ptr += dst_stride;
+ pred_ptr += pred_stride;
+ }
+
+}
+
+void vp8_short_inv_walsh4x4_c(short *input, short *mb_dqcoeff)
+{
+ short output[16];
+ int i;
+ int a1, b1, c1, d1;
+ int a2, b2, c2, d2;
+ short *ip = input;
+ short *op = output;
+
+ for (i = 0; i < 4; i++)
+ {
+ a1 = ip[0] + ip[12];
+ b1 = ip[4] + ip[8];
+ c1 = ip[4] - ip[8];
+ d1 = ip[0] - ip[12];
+
+ op[0] = a1 + b1;
+ op[4] = c1 + d1;
+ op[8] = a1 - b1;
+ op[12] = d1 - c1;
+ ip++;
+ op++;
+ }
+
+ ip = output;
+ op = output;
+
+ for (i = 0; i < 4; i++)
+ {
+ a1 = ip[0] + ip[3];
+ b1 = ip[1] + ip[2];
+ c1 = ip[1] - ip[2];
+ d1 = ip[0] - ip[3];
+
+ a2 = a1 + b1;
+ b2 = c1 + d1;
+ c2 = a1 - b1;
+ d2 = d1 - c1;
+
+ op[0] = (a2 + 3) >> 3;
+ op[1] = (b2 + 3) >> 3;
+ op[2] = (c2 + 3) >> 3;
+ op[3] = (d2 + 3) >> 3;
+
+ ip += 4;
+ op += 4;
+ }
+
+ for(i = 0; i < 16; i++)
+ {
+ mb_dqcoeff[i * 16] = output[i];
+ }
+}
+
+void vp8_short_inv_walsh4x4_1_c(short *input, short *mb_dqcoeff)
+{
+ int i;
+ int a1;
+
+ a1 = ((input[0] + 3) >> 3);
+ for(i = 0; i < 16; i++)
+ {
+ mb_dqcoeff[i * 16] = a1;
+ }
+}