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authorDimitri Sokolyuk <demon@dim13.org>2018-09-27 20:03:23 +0200
committerDimitri Sokolyuk <demon@dim13.org>2018-09-27 20:03:23 +0200
commit14bb08c1df8db9ec6c8a05520d4eee67971235d9 (patch)
treefc820e59c26ed4c5e87e65737909b47959f0faa5 /vendor/golang.org/x/image/vp8/quant.go
parent54eb169e8fc9bc0357139e7c259e977b184f8fbb (diff)
mod tidy
Diffstat (limited to 'vendor/golang.org/x/image/vp8/quant.go')
-rw-r--r--vendor/golang.org/x/image/vp8/quant.go98
1 files changed, 0 insertions, 98 deletions
diff --git a/vendor/golang.org/x/image/vp8/quant.go b/vendor/golang.org/x/image/vp8/quant.go
deleted file mode 100644
index da43616..0000000
--- a/vendor/golang.org/x/image/vp8/quant.go
+++ /dev/null
@@ -1,98 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package vp8
-
-// This file implements parsing the quantization factors.
-
-// quant are DC/AC quantization factors.
-type quant struct {
- y1 [2]uint16
- y2 [2]uint16
- uv [2]uint16
-}
-
-// clip clips x to the range [min, max] inclusive.
-func clip(x, min, max int32) int32 {
- if x < min {
- return min
- }
- if x > max {
- return max
- }
- return x
-}
-
-// parseQuant parses the quantization factors, as specified in section 9.6.
-func (d *Decoder) parseQuant() {
- baseQ0 := d.fp.readUint(uniformProb, 7)
- dqy1DC := d.fp.readOptionalInt(uniformProb, 4)
- const dqy1AC = 0
- dqy2DC := d.fp.readOptionalInt(uniformProb, 4)
- dqy2AC := d.fp.readOptionalInt(uniformProb, 4)
- dquvDC := d.fp.readOptionalInt(uniformProb, 4)
- dquvAC := d.fp.readOptionalInt(uniformProb, 4)
- for i := 0; i < nSegment; i++ {
- q := int32(baseQ0)
- if d.segmentHeader.useSegment {
- if d.segmentHeader.relativeDelta {
- q += int32(d.segmentHeader.quantizer[i])
- } else {
- q = int32(d.segmentHeader.quantizer[i])
- }
- }
- d.quant[i].y1[0] = dequantTableDC[clip(q+dqy1DC, 0, 127)]
- d.quant[i].y1[1] = dequantTableAC[clip(q+dqy1AC, 0, 127)]
- d.quant[i].y2[0] = dequantTableDC[clip(q+dqy2DC, 0, 127)] * 2
- d.quant[i].y2[1] = dequantTableAC[clip(q+dqy2AC, 0, 127)] * 155 / 100
- if d.quant[i].y2[1] < 8 {
- d.quant[i].y2[1] = 8
- }
- // The 117 is not a typo. The dequant_init function in the spec's Reference
- // Decoder Source Code (http://tools.ietf.org/html/rfc6386#section-9.6 Page 145)
- // says to clamp the LHS value at 132, which is equal to dequantTableDC[117].
- d.quant[i].uv[0] = dequantTableDC[clip(q+dquvDC, 0, 117)]
- d.quant[i].uv[1] = dequantTableAC[clip(q+dquvAC, 0, 127)]
- }
-}
-
-// The dequantization tables are specified in section 14.1.
-var (
- dequantTableDC = [128]uint16{
- 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,
- }
- dequantTableAC = [128]uint16{
- 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,
- }
-)