mirror of https://bitbucket.org/ausocean/av.git
ADPCM: removed unneeded files and renamed files
This commit is contained in:
Trek H
parent
9939de26ac
commit
35d98f1a73
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@ -1,265 +0,0 @@
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package adpcm
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import (
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"encoding/binary"
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"fmt"
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"math"
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)
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// table of index changes
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var indexTable = []int16{
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-1, -1, -1, -1, 2, 4, 6, 8,
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-1, -1, -1, -1, 2, 4, 6, 8,
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}
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// quantize step size table
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var stepTable = []int16{
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7, 8, 9, 10, 11, 12, 13, 14,
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16, 17, 19, 21, 23, 25, 28, 31,
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34, 37, 41, 45, 50, 55, 60, 66,
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73, 80, 88, 97, 107, 118, 130, 143,
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157, 173, 190, 209, 230, 253, 279, 307,
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337, 371, 408, 449, 494, 544, 598, 658,
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724, 796, 876, 963, 1060, 1166, 1282, 1411,
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1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024,
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3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484,
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7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
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15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794,
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32767,
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}
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var (
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encPred int16
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encIndex int16
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decPred int16
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decIndex int16
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decStep int16 = 7
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pCount int
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pNum = 8
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)
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// EncodeSample takes a single 16 bit PCM sample and
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// returns a byte of which the last 4 bits are an encoded ADPCM nibble
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func EncodeSample(sample int16) byte {
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// find difference from predicted sample
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delta := sample - encPred
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// set sign bit and find absolute value of difference
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var nibble byte
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if delta < 0 {
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nibble = 8
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delta = -delta
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}
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step := stepTable[encIndex]
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diff := step >> 3
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var mask byte = 4
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// quantize delta down to four bits
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for i := 0; i < 3; i++ {
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if delta > step {
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nibble |= mask
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delta -= step
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diff += step
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}
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mask >>= 1
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step >>= 1
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}
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// adjust predicted sample based on calculated difference
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if nibble&8 != 0 {
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encPred -= diff
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} else {
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encPred += diff
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}
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// check for underflow and overflow
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if encPred < math.MinInt16 {
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encPred = math.MinInt16
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} else if encPred > math.MaxInt16 {
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encPred = math.MaxInt16
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}
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encIndex += indexTable[nibble&7]
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// check for underflow and overflow
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if encIndex < 0 {
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encIndex = 0
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} else if encIndex > int16(len(stepTable)-1) {
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encIndex = int16(len(stepTable) - 1)
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}
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return nibble
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}
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// DecodeSample takes a byte, the last 4 bits of which contain a single
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// 4 bit ADPCM nibble, and returns a 16 bit decoded PCM sample
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func DecodeSample(nibble byte) int16 {
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// compute predicted sample estimate (decPred):
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// calculate difference
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var diff int16
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if nibble&4 != 0 {
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diff += decStep
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}
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if nibble&2 != 0 {
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diff += decStep >> 1
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}
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if nibble&1 != 0 {
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diff += decStep >> 2
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}
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diff += decStep >> 3
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// account for sign bit
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if nibble&8 != 0 {
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diff = -diff
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}
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// adjust predicted sample based on calculated difference
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decPred += diff
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// check for overflow and underflow
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if decPred > math.MaxInt16 {
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decPred = math.MaxInt16
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} else if decPred < math.MinInt16 {
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decPred = math.MinInt16
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}
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// compute new step size:
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// adjust index into step size lookup table using nibble
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decIndex += indexTable[nibble]
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// check for overflow and underflow
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if decIndex < 0 {
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decIndex = 0
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} else if decIndex > int16(len(stepTable)-1) {
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decIndex = int16(len(stepTable) - 1)
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}
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// find new quantizer step size
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decStep = stepTable[decIndex]
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return decPred
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}
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func calcHead(sample []byte) ([]byte, error) {
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if len(sample) != 2 {
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return nil, fmt.Errorf("length of given byte array is: %v, expected: 2", len(sample))
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}
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intSample := int16(binary.LittleEndian.Uint16(sample))
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// if pCount < pNum {
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// fmt.Println("calcHead enc", intSample)
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// fmt.Println(encIndex, encPred)
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// }
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EncodeSample(intSample)
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head := make([]byte, 2)
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head[0] = sample[0]
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head[1] = sample[1]
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// if pCount < pNum {
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// fmt.Println("after calcHead enc")
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// fmt.Println(encIndex, encPred)
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// }
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head = append(head, byte(uint16(encIndex)))
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head = append(head, byte(0x00))
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return head, nil
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}
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func EncodeBlock(block []byte) ([]byte, error) {
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if len(block) != 1010 {
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return nil, fmt.Errorf("unsupported block size. Given: %v, expected: 1010, ie. 505 16-bit PCM samples", len(block))
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}
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result, err := calcHead(block[0:2])
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if err != nil {
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return nil, err
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}
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for i := 2; i < len(block); i++ {
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if (i+1)%4 == 0 {
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// var intsample int16
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// if pCount < pNum {
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// fmt.Println(block[2], block[3])
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// fmt.Println("first enc", block[i-1:i+1])
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// fmt.Println(encIndex, encPred)
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// }
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sample2 := EncodeSample(int16(binary.LittleEndian.Uint16(block[i-1 : i+1])))
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// if pCount < pNum {
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// intsample = int16(binary.LittleEndian.Uint16(block[i+1 : i+3]))
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// fmt.Println("second enc", int16(intsample))
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// fmt.Println(encIndex, encPred)
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// }
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sample := EncodeSample(int16(binary.LittleEndian.Uint16(block[i+1 : i+3])))
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// if pCount < pNum {
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// fmt.Println("after enc")
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// fmt.Println(encIndex, encPred)
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// fmt.Println()
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// }
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result = append(result, byte((sample<<4)|sample2))
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pCount++
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}
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}
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return result, nil
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}
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func DecodeBlock(block []byte) ([]byte, error) {
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if len(block) != 256 {
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return nil, fmt.Errorf("unsupported block size. Given: %v, expected: 256", len(block))
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}
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if pCount < pNum {
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fmt.Println("pre dec", block[0:8])
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fmt.Println(decIndex, decPred, decStep)
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}
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var result []byte
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decPred = int16(binary.LittleEndian.Uint16(block[0:2]))
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decIndex = int16(block[2])
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decStep = stepTable[decIndex]
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result = append(result, block[0:2]...)
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for i := 4; i < len(block); i++ {
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originalSample := block[i]
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secondSample := byte(originalSample >> 4)
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firstSample := byte((secondSample << 4) ^ originalSample)
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if pCount < pNum {
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fmt.Println("first dec", firstSample, originalSample, len(block))
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fmt.Println(decIndex, decPred, decStep)
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}
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firstBytes := make([]byte, 2)
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binary.LittleEndian.PutUint16(firstBytes, uint16(DecodeSample(firstSample)))
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result = append(result, firstBytes...)
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if pCount < pNum {
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fmt.Println("second dec", secondSample)
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fmt.Println(decIndex, decPred, decStep)
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fmt.Println()
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}
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secondBytes := make([]byte, 2)
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binary.LittleEndian.PutUint16(secondBytes, uint16(DecodeSample(secondSample)))
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result = append(result, secondBytes...)
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pCount++
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}
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return result, nil
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}
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@ -1,70 +0,0 @@
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package main
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import (
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"flag"
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"fmt"
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"io/ioutil"
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"os"
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"github.com/bovarysme/adpcm"
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"github.com/go-audio/audio"
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"github.com/go-audio/wav"
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)
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func main() {
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var inPath string
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var nChannels int
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var rate int
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var bps int
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flag.StringVar(&inPath, "path", "out.adpcm", "file path of input data")
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flag.IntVar(&nChannels, "channels", 1, "number of channels in adpcm data")
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flag.IntVar(&rate, "rate", 8000, "number of channels in adpcm data")
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flag.IntVar(&bps, "bps", 16, "number of channels in adpcm data")
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flag.Parse()
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//read adpcm
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comp, err := ioutil.ReadFile(inPath)
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if err != nil {
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panic(err)
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}
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fmt.Println("Read ADPCM from " + inPath + ". First 8 bytes: ")
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for i := 0; i < len(comp) && i < 16; i++ {
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fmt.Print(comp[i], ", ")
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}
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fmt.Println()
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//decode adpcm
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var decoded []int
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deco := adpcm.NewDecoder(nChannels)
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deco.Decode(comp, &decoded)
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//encode wav and save to file
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finalWavPath := "decoded.wav"
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of, err := os.Create(finalWavPath)
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if err != nil {
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panic(err)
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}
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defer of.Close()
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sampleBytes := bps / 8
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// normal uncompressed WAV format
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wavformat := 1
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enc := wav.NewEncoder(of, rate, bps, nChannels, wavformat)
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format := &audio.Format{
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NumChannels: nChannels,
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SampleRate: rate,
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}
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intBuf := &audio.IntBuffer{Data: decoded, Format: format, SourceBitDepth: sampleBytes * 8}
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if err := enc.Write(intBuf); err != nil {
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panic(err)
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}
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if err := enc.Close(); err != nil {
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panic(err)
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}
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fmt.Printf("Saved audio to %s\n", finalWavPath)
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}
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@ -1,30 +0,0 @@
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package main
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import (
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"fmt"
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"bitbucket.org/ausocean/av/cmd/adpcmgo"
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)
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func main() {
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var input byte = 4
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sample := adpcmgo.DecodeSample(input)
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fmt.Println(sample)
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input = 5
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sample = adpcmgo.DecodeSample(input)
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fmt.Println(sample)
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input = 6
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sample = adpcmgo.DecodeSample(input)
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fmt.Println(sample)
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input = 16
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sample = adpcmgo.DecodeSample(input)
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fmt.Println(sample)
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input = 235
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sample = adpcmgo.DecodeSample(input)
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fmt.Println(sample)
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}
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@ -1,47 +0,0 @@
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package main
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import (
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"flag"
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"fmt"
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"io/ioutil"
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"bitbucket.org/ausocean/av/cmd/adpcmgo"
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)
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func main() {
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var inPath string
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flag.StringVar(&inPath, "path", "test.pcm", "file path of input data")
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flag.Parse()
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//read pcm
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pcm, err := ioutil.ReadFile(inPath)
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if err != nil {
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panic(err)
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}
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//encode adpcm
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var comp []byte
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start := 0
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for i := 0; i < len(pcm); i++ {
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if i%1010 == 1009 {
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block := pcm[start : i+1]
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encBlock, err := adpcmgo.EncodeBlock(block)
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if err != nil {
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//todo: use correct logging of error
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panic(err)
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}
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comp = append(comp, encBlock...)
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start = i + 1
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}
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}
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// save adpcm to file
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adpcmPath := "out.adpcm"
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err = ioutil.WriteFile(adpcmPath, comp, 0644)
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if err != nil {
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panic(err)
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}
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fmt.Println("Saved ADPCM to " + adpcmPath + ". First 8 bytes: ")
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for i := 0; i < len(comp) && i < 16; i++ {
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fmt.Print(comp[i], ", ")
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}
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fmt.Println()
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}
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@ -1,111 +0,0 @@
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package main
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import (
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"encoding/binary"
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"flag"
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"fmt"
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"io/ioutil"
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"os"
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"github.com/bovarysme/adpcm"
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"github.com/go-audio/audio"
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"github.com/go-audio/wav"
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"github.com/pkg/errors"
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)
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// This program is for compare data size of pcm and adpcm, it takes a wav file and compresses and encodes it to adpcm,
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// the adpcm byte array is stored as a file and then the adpcm is decoded and the result saved as final.wav
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func main() {
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//open wav
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var wavPath string
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flag.StringVar(&wavPath, "path", "before_compression.wav", "file path of input data")
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flag.Parse()
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f, err := os.Open(wavPath)
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if err != nil {
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panic(err)
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}
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defer f.Close()
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//decode wav
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dec := wav.NewDecoder(f)
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if !dec.IsValidFile() {
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panic(errors.Errorf("invalid WAV file %q", wavPath))
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}
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sampleRate, nchannels, bps := int(dec.SampleRate), int(dec.NumChans), int(dec.BitDepth)
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buf, err := dec.FullPCMBuffer()
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if err != nil {
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panic(err)
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}
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fmt.Println("Decoded wav. First 8 samples: ")
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for i := 0; i < len(buf.Data) && i < 8; i++ {
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fmt.Print(buf.Data[i], ", ")
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}
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fmt.Println()
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// save pcm to file
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var pcmBytes []byte
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for _, sample := range buf.Data {
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bs := make([]byte, 2)
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binary.LittleEndian.PutUint16(bs, uint16(sample))
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pcmBytes = append(pcmBytes, bs[0], bs[1])
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}
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pcmPath := "out.pcm"
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err = ioutil.WriteFile(pcmPath, pcmBytes, 0644)
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if err != nil {
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panic(err)
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}
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fmt.Println("Saved raw PCM to " + pcmPath + ". First 8 bytes: ")
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for i := 0; i < len(pcmBytes) && i < 8; i++ {
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fmt.Print(pcmBytes[i], ", ")
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}
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fmt.Println()
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//encode adpcm
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var comp []byte
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adpcm.Encode(buf.Data, &comp)
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// save adpcm to file
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adpcmPath := "out.adpcm"
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err = ioutil.WriteFile(adpcmPath, comp, 0644)
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if err != nil {
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panic(err)
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}
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fmt.Println("Saved ADPCM to " + adpcmPath + ". First 8 bytes: ")
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for i := 0; i < len(comp) && i < 16; i++ {
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fmt.Print(comp[i], ", ")
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}
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fmt.Println()
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//decode adpcm
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var decoded []int
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deco := adpcm.NewDecoder(nchannels)
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deco.Decode(comp, &decoded)
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//encode wav and save to file
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finalWavPath := "final.wav"
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of, err := os.Create(finalWavPath)
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if err != nil {
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panic(err)
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}
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defer of.Close()
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sampleBytes := bps / 8
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// normal uncompressed WAV format
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wavformat := 1
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enc := wav.NewEncoder(of, sampleRate, bps, nchannels, wavformat)
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format := &audio.Format{
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NumChannels: nchannels,
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SampleRate: sampleRate,
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}
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intBuf := &audio.IntBuffer{Data: decoded, Format: format, SourceBitDepth: sampleBytes * 8}
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if err := enc.Write(intBuf); err != nil {
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panic(err)
|
||||
}
|
||||
|
||||
if err := enc.Close(); err != nil {
|
||||
panic(err)
|
||||
}
|
||||
fmt.Printf("Saved audio to %s\n", finalWavPath)
|
||||
|
||||
}
|
||||
|
|
@ -1,30 +0,0 @@
|
|||
package main
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
|
||||
"bitbucket.org/ausocean/av/cmd/adpcmgo"
|
||||
)
|
||||
|
||||
func main() {
|
||||
|
||||
input := -370
|
||||
nibble := adpcmgo.EncodeSample(input)
|
||||
fmt.Println(nibble)
|
||||
|
||||
input = 8
|
||||
nibble = adpcmgo.EncodeSample(input)
|
||||
fmt.Println(nibble)
|
||||
|
||||
input = 1
|
||||
nibble = adpcmgo.EncodeSample(input)
|
||||
fmt.Println(nibble)
|
||||
|
||||
input = 31793
|
||||
nibble = adpcmgo.EncodeSample(input)
|
||||
fmt.Println(nibble)
|
||||
|
||||
input = -7386
|
||||
nibble = adpcmgo.EncodeSample(input)
|
||||
fmt.Println(nibble)
|
||||
}
|
||||
|
|
@ -1,175 +0,0 @@
|
|||
package adpcmgo
|
||||
|
||||
import (
|
||||
"encoding/binary"
|
||||
"fmt"
|
||||
"math"
|
||||
)
|
||||
|
||||
// table of index changes
|
||||
var indexTable = []int16{
|
||||
-1, -1, -1, -1, 2, 4, 6, 8,
|
||||
-1, -1, -1, -1, 2, 4, 6, 8,
|
||||
}
|
||||
|
||||
// quantize step size table
|
||||
var stepTable = []int16{
|
||||
7, 8, 9, 10, 11, 12, 13, 14,
|
||||
16, 17, 19, 21, 23, 25, 28, 31,
|
||||
34, 37, 41, 45, 50, 55, 60, 66,
|
||||
73, 80, 88, 97, 107, 118, 130, 143,
|
||||
157, 173, 190, 209, 230, 253, 279, 307,
|
||||
337, 371, 408, 449, 494, 544, 598, 658,
|
||||
724, 796, 876, 963, 1060, 1166, 1282, 1411,
|
||||
1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024,
|
||||
3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484,
|
||||
7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
|
||||
15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794,
|
||||
32767,
|
||||
}
|
||||
|
||||
var (
|
||||
encPred int16
|
||||
encIndex int16
|
||||
decPred int16
|
||||
decIndex int16
|
||||
decStep int16 = 7
|
||||
)
|
||||
|
||||
// EncodeSample takes a single 16 bit PCM sample and
|
||||
// returns a byte of which the last 4 bits are an encoded ADPCM nibble
|
||||
func EncodeSample(sample int16) byte {
|
||||
|
||||
// find difference from predicted sample
|
||||
delta := sample - encPred
|
||||
|
||||
// set sign bit and find absolute value of difference
|
||||
var nibble byte
|
||||
if delta < 0 {
|
||||
nibble = 8
|
||||
delta = -delta
|
||||
}
|
||||
|
||||
step := stepTable[encIndex]
|
||||
diff := step >> 3
|
||||
var mask byte = 4
|
||||
|
||||
// quantize delta down to four bits
|
||||
for i := 0; i < 3; i++ {
|
||||
if delta > step {
|
||||
nibble |= mask
|
||||
delta -= step
|
||||
diff += step
|
||||
}
|
||||
mask >>= 1
|
||||
step >>= 1
|
||||
}
|
||||
|
||||
// adjust predicted sample based on calculated difference
|
||||
if nibble&8 != 0 {
|
||||
encPred -= diff
|
||||
} else {
|
||||
encPred += diff
|
||||
}
|
||||
|
||||
// check for underflow and overflow
|
||||
if encPred < math.MinInt16 {
|
||||
encPred = math.MinInt16
|
||||
} else if encPred > math.MaxInt16 {
|
||||
encPred = math.MaxInt16
|
||||
}
|
||||
|
||||
encIndex += indexTable[nibble&7]
|
||||
|
||||
// check for underflow and overflow
|
||||
if encIndex < 0 {
|
||||
encIndex = 0
|
||||
} else if encIndex > int16(len(stepTable)-1) {
|
||||
encIndex = int16(len(stepTable) - 1)
|
||||
}
|
||||
|
||||
return nibble
|
||||
}
|
||||
|
||||
// DecodeSample takes a byte, the last 4 bits of which contain a single
|
||||
// 4 bit ADPCM nibble, and returns a 16 bit decoded PCM sample
|
||||
func DecodeSample(nibble byte) int16 {
|
||||
|
||||
// compute predicted sample estimate (decPred):
|
||||
|
||||
// calculate difference
|
||||
var diff int16
|
||||
if nibble&4 != 0 {
|
||||
diff += decStep
|
||||
}
|
||||
if nibble&2 != 0 {
|
||||
diff += decStep >> 1
|
||||
}
|
||||
if nibble&1 != 0 {
|
||||
diff += decStep >> 2
|
||||
}
|
||||
diff += decStep >> 3
|
||||
// account for sign bit
|
||||
if nibble&8 != 0 {
|
||||
diff = -diff
|
||||
}
|
||||
// adjust predicted sample based on calculated difference
|
||||
decPred += diff
|
||||
|
||||
// check for overflow and underflow
|
||||
if decPred > math.MaxInt16 {
|
||||
decPred = math.MaxInt16
|
||||
} else if decPred < math.MinInt16 {
|
||||
decPred = math.MinInt16
|
||||
}
|
||||
|
||||
// compute new step size:
|
||||
|
||||
// adjust index into step size lookup table using nibble
|
||||
decIndex += indexTable[nibble]
|
||||
// check for overflow and underflow
|
||||
if decIndex < 0 {
|
||||
decIndex = 0
|
||||
} else if decIndex > int16(len(stepTable)-1) {
|
||||
decIndex = int16(len(stepTable) - 1)
|
||||
}
|
||||
// find new quantizer step size
|
||||
decStep = stepTable[decIndex]
|
||||
|
||||
return decPred
|
||||
}
|
||||
|
||||
func calcHead(sample []byte) []byte {
|
||||
fmt.Println(sample[0], sample[1])
|
||||
intSample := int16(binary.LittleEndian.Uint16(sample))
|
||||
|
||||
fmt.Println("before enc", intSample)
|
||||
|
||||
EncodeSample(intSample)
|
||||
head := sample
|
||||
|
||||
fmt.Println(encIndex)
|
||||
|
||||
head = append(head, byte(uint16(encIndex)))
|
||||
head = append(head, byte(0x00))
|
||||
return head
|
||||
}
|
||||
|
||||
func EncodeBlock(block []byte) ([]byte, error) {
|
||||
if len(block) != 1010 {
|
||||
return nil, fmt.Errorf("unsupported block size. Given: %v, expected: 1010, ie. 505 16-bit PCM samples", len(block))
|
||||
}
|
||||
|
||||
result := calcHead(block[0:2])
|
||||
|
||||
for i := 2; i < len(block); i++ {
|
||||
if (i+1)%4 == 0 {
|
||||
sample2 := EncodeSample(int16(binary.LittleEndian.Uint16(block[i-1 : i+1])))
|
||||
sample := EncodeSample(int16(binary.LittleEndian.Uint16(block[i+1 : i+3])))
|
||||
result = append(result, byte((sample<<4)|sample2))
|
||||
|
||||
}
|
||||
}
|
||||
|
||||
return result, nil
|
||||
}
|
||||
Loading…
Reference in New Issue