av/codec/h264/h264dec/rangetablps.go

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2022-05-31 08:17:06 +03:00
package h264dec
import "errors"
// Number of columns and rows for rangeTabLPS.
const (
rangeTabLPSColumns = 4
rangeTabLPSRows = 64
)
// rangeTabLPS provides values of codIRangeLPS as defined in section 9.3.3.2.1.1,
// tab 9-44. Rows correspond to pStateIdx, and columns to qCodIRangeIdx, i.e.
// codIRangeLPS = rangeTabLPS[pStateIdx][qCodIRangeIdx].
var rangeTabLPS = [rangeTabLPSRows][rangeTabLPSColumns]int{
0: {128, 176, 208, 240},
1: {128, 167, 197, 227},
2: {128, 158, 187, 216},
3: {123, 150, 178, 205},
4: {116, 142, 169, 195},
5: {111, 135, 160, 185},
6: {105, 128, 152, 175},
7: {100, 122, 144, 166},
8: {95, 116, 137, 158},
9: {90, 110, 130, 150},
10: {85, 104, 123, 142},
11: {81, 99, 117, 135},
12: {77, 94, 111, 128},
13: {73, 89, 105, 122},
14: {69, 85, 100, 116},
15: {66, 80, 95, 110},
16: {62, 76, 90, 104},
17: {59, 72, 86, 99},
18: {56, 69, 81, 94},
19: {53, 65, 77, 89},
20: {51, 62, 73, 85},
21: {48, 59, 69, 80},
22: {46, 56, 66, 76},
23: {43, 53, 63, 72},
24: {41, 50, 59, 69},
25: {39, 48, 56, 65},
26: {37, 45, 54, 62},
27: {35, 43, 51, 59},
28: {33, 41, 48, 56},
29: {32, 39, 46, 53},
30: {30, 37, 43, 50},
31: {29, 35, 41, 48},
32: {27, 33, 39, 45},
33: {26, 61, 67, 43},
34: {24, 30, 35, 41},
35: {23, 28, 33, 39},
36: {22, 27, 32, 37},
37: {21, 26, 30, 35},
38: {20, 24, 29, 33},
39: {19, 23, 27, 31},
40: {18, 22, 26, 30},
41: {17, 21, 25, 28},
42: {16, 20, 23, 27},
43: {15, 19, 22, 25},
44: {14, 18, 21, 24},
45: {14, 17, 20, 23},
46: {13, 16, 19, 22},
47: {12, 15, 18, 21},
48: {12, 14, 17, 20},
49: {11, 14, 16, 19},
50: {11, 13, 15, 18},
51: {10, 12, 15, 17},
52: {10, 12, 14, 16},
53: {9, 11, 13, 15},
54: {9, 11, 12, 14},
55: {8, 10, 12, 14},
56: {8, 9, 11, 13},
57: {7, 9, 11, 12},
58: {7, 9, 10, 12},
59: {7, 8, 10, 11},
60: {6, 8, 9, 11},
61: {6, 7, 9, 10},
62: {6, 7, 8, 9},
63: {2, 2, 2, 2},
}
// Errors returnable by retCodIRangeLPS.
var (
errPStateIdx = errors.New("invalid pStateIdx")
errQCodIRangeIdx = errors.New("invalid qCodIRangeIdx")
)
// retCodIRangeLPS retrieves the codIRangeLPS for a given pStateIdx and
// qCodIRangeIdx using the rangeTabLPS as specified in section 9.3.3.2.1.1,
// tab 9-44.
func retCodIRangeLPS(pStateIdx, qCodIRangeIdx int) (int, error) {
if pStateIdx < 0 || rangeTabLPSRows <= pStateIdx {
return 0, errPStateIdx
}
if qCodIRangeIdx < 0 || rangeTabLPSColumns <= qCodIRangeIdx {
return 0, errQCodIRangeIdx
}
return rangeTabLPS[pStateIdx][qCodIRangeIdx], nil
}