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-rw-r--r--media/libvpx/vp8/common/quant_common.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/media/libvpx/vp8/common/quant_common.c b/media/libvpx/vp8/common/quant_common.c
new file mode 100644
index 000000000..05f921070
--- /dev/null
+++ b/media/libvpx/vp8/common/quant_common.c
@@ -0,0 +1,135 @@
+/*
+ * 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 "quant_common.h"
+
+static const int dc_qlookup[QINDEX_RANGE] =
+{
+ 4, 5, 6, 7, 8, 9, 10, 10, 11, 12, 13, 14, 15, 16, 17, 17,
+ 18, 19, 20, 20, 21, 21, 22, 22, 23, 23, 24, 25, 25, 26, 27, 28,
+ 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43,
+ 44, 45, 46, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,
+ 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
+ 75, 76, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,
+ 91, 93, 95, 96, 98, 100, 101, 102, 104, 106, 108, 110, 112, 114, 116, 118,
+ 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 143, 145, 148, 151, 154, 157,
+};
+
+static const int ac_qlookup[QINDEX_RANGE] =
+{
+ 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
+ 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
+ 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,
+ 52, 53, 54, 55, 56, 57, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76,
+ 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108,
+ 110, 112, 114, 116, 119, 122, 125, 128, 131, 134, 137, 140, 143, 146, 149, 152,
+ 155, 158, 161, 164, 167, 170, 173, 177, 181, 185, 189, 193, 197, 201, 205, 209,
+ 213, 217, 221, 225, 229, 234, 239, 245, 249, 254, 259, 264, 269, 274, 279, 284,
+};
+
+
+int vp8_dc_quant(int QIndex, int Delta)
+{
+ int retval;
+
+ QIndex = QIndex + Delta;
+
+ if (QIndex > 127)
+ QIndex = 127;
+ else if (QIndex < 0)
+ QIndex = 0;
+
+ retval = dc_qlookup[ QIndex ];
+ return retval;
+}
+
+int vp8_dc2quant(int QIndex, int Delta)
+{
+ int retval;
+
+ QIndex = QIndex + Delta;
+
+ if (QIndex > 127)
+ QIndex = 127;
+ else if (QIndex < 0)
+ QIndex = 0;
+
+ retval = dc_qlookup[ QIndex ] * 2;
+ return retval;
+
+}
+int vp8_dc_uv_quant(int QIndex, int Delta)
+{
+ int retval;
+
+ QIndex = QIndex + Delta;
+
+ if (QIndex > 127)
+ QIndex = 127;
+ else if (QIndex < 0)
+ QIndex = 0;
+
+ retval = dc_qlookup[ QIndex ];
+
+ if (retval > 132)
+ retval = 132;
+
+ return retval;
+}
+
+int vp8_ac_yquant(int QIndex)
+{
+ int retval;
+
+ if (QIndex > 127)
+ QIndex = 127;
+ else if (QIndex < 0)
+ QIndex = 0;
+
+ retval = ac_qlookup[ QIndex ];
+ return retval;
+}
+
+int vp8_ac2quant(int QIndex, int Delta)
+{
+ int retval;
+
+ QIndex = QIndex + Delta;
+
+ if (QIndex > 127)
+ QIndex = 127;
+ else if (QIndex < 0)
+ QIndex = 0;
+
+ /* For all x in [0..284], x*155/100 is bitwise equal to (x*101581) >> 16.
+ * The smallest precision for that is '(x*6349) >> 12' but 16 is a good
+ * word size. */
+ retval = (ac_qlookup[ QIndex ] * 101581) >> 16;
+
+ if (retval < 8)
+ retval = 8;
+
+ return retval;
+}
+int vp8_ac_uv_quant(int QIndex, int Delta)
+{
+ int retval;
+
+ QIndex = QIndex + Delta;
+
+ if (QIndex > 127)
+ QIndex = 127;
+ else if (QIndex < 0)
+ QIndex = 0;
+
+ retval = ac_qlookup[ QIndex ];
+ return retval;
+}