Merged in encoding (pull request #45)

encoding: remove in-bound chans

Approved-by: Alan Noble <anoble@gmail.com>
This commit is contained in:
kortschak 2018-08-23 04:31:38 +00:00
commit 90fac96048
18 changed files with 446 additions and 1000 deletions

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@ -1,288 +0,0 @@
/*
NAME
flv_generator.go
DESCRIPTION
See Readme.md
AUTHOR
Saxon Nelson-Milton <saxon@ausocean.org>
LICENSE
flv_generator.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package generator
import (
"time"
"bitbucket.org/ausocean/av/flv"
)
const (
inputChanLength = 500
outputChanLength = 500
audioSize = 18
videoHeaderSize = 16
)
// Data representing silent audio (required for youtube)
var (
dummyAudioTag1Data = []byte{
0x00, 0x12, 0x08, 0x56, 0xe5, 0x00,
}
dummyAudioTag2Data = []byte{
0x01, 0xdc, 0x00, 0x4c, 0x61, 0x76, 0x63, 0x35, 0x38,
0x2e, 0x36, 0x2e, 0x31, 0x30, 0x32, 0x00, 0x02, 0x30,
0x40, 0x0e,
}
)
// flvGenerator provides properties required for the generation of flv video
// from raw video data
type flvGenerator struct {
fps int
inputChan chan []byte
outputChan chan []byte
audio bool
video bool
lastTagSize int
header flv.Header
startTime time.Time
firstTag bool
isGenerating bool
}
// InputChan returns the input channel to the generator. This is where the
// raw data frames are entered into the generator
func (g *flvGenerator) InputChan() chan []byte {
return g.inputChan
}
// OutputChan retuns the output chan of the generator - this is where the
// flv packets (more specifically tags) are outputted.
func (g *flvGenerator) OutputChan() <-chan []byte {
return g.outputChan
}
// NewFlvGenerator retuns an instance of the flvGenerator struct
func NewFlvGenerator(audio, video bool, fps int) *flvGenerator {
return &flvGenerator{
fps: fps,
audio: audio,
video: video,
inputChan: make(chan []byte, inputChanLength),
outputChan: make(chan []byte, outputChanLength),
firstTag: true,
}
}
// Start begins the generation routine - i.e. if raw data is given to the input
// channel flv tags will be produced and available from the output channel.
func (g *flvGenerator) Start() {
g.isGenerating = true
go g.generate()
}
func (g *flvGenerator) Stop() {
g.isGenerating = false
}
// GenHeader generates the flv header and sends it down the output chan for use
// This will generally be called once at the start of file writing/transmission.
func (g *flvGenerator) GenHeader() {
header := flv.Header{
HasAudio: g.audio,
HasVideo: g.video,
}
g.outputChan <- header.Bytes()
}
// getNextTimestamp generates and returns the next timestamp based on current time
func (g *flvGenerator) getNextTimestamp() (timestamp uint32) {
if g.firstTag {
g.startTime = time.Now()
g.firstTag = false
return 0
}
return uint32(time.Now().Sub(g.startTime).Seconds() * float64(1000))
}
// http://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-H.264-200305-S!!PDF-E&type=items
// Table 7-1 NAL unit type codes
const (
nonIdrPic = 1
idrPic = 5
suppEnhInf = 6
seqParamSet = 7
paramSet = 8
)
// isKeyFrame returns true if the passed frame data represents that of a keyframe
// FIXME(kortschak): Clarify and document the logic of this functions.
func isKeyFrame(frame []byte) bool {
sc := frameScanner{buf: frame}
for {
b, ok := sc.readByte()
if !ok {
return false
}
for i := 1; b == 0x00 && i < 4; i++ {
b, ok = sc.readByte()
if !ok {
return false
}
if b != 0x01 || (i != 3 && i != 2) {
continue
}
b, ok = sc.readByte()
if !ok {
return false
}
switch nalTyp := b & 0x1f; nalTyp {
case idrPic, suppEnhInf:
return true
case nonIdrPic:
return false
}
}
}
return false
}
// isSequenceHeader returns true if the passed frame data represents that of a
// a sequence header.
// FIXME(kortschak): Clarify and document the logic of this functions.
func isSequenceHeader(frame []byte) bool {
sc := frameScanner{buf: frame}
for {
b, ok := sc.readByte()
if !ok {
return false
}
for i := 1; b == 0x00 && i != 4; i++ {
b, ok = sc.readByte()
if !ok {
return false
}
if b != 0x01 || (i != 2 && i != 3) {
continue
}
b, ok = sc.readByte()
if !ok {
return false
}
switch nalTyp := b & 0x1f; nalTyp {
case suppEnhInf, seqParamSet, paramSet:
return true
case nonIdrPic, idrPic:
return false
}
}
}
}
type frameScanner struct {
off int
buf []byte
}
func (s *frameScanner) readByte() (b byte, ok bool) {
if s.off >= len(s.buf) {
return 0, false
}
b = s.buf[s.off]
s.off++
return b, true
}
// generate takes in raw video data from the input chan and packetises it into
// flv tags, which are then passed to the output channel.
func (g *flvGenerator) generate() {
g.GenHeader()
var frameType byte
var packetType byte
for g.isGenerating {
select {
default:
time.Sleep(time.Duration(5) * time.Millisecond)
case frame := <-g.inputChan:
timeStamp := g.getNextTimestamp()
// Do we have video to send off?
if g.video {
if isKeyFrame(frame) {
frameType = flv.KeyFrameType
} else {
frameType = flv.InterFrameType
}
if isSequenceHeader(frame) {
packetType = flv.SequenceHeader
} else {
packetType = flv.AVCNALU
}
tag := flv.VideoTag{
TagType: uint8(flv.VideoTagType),
DataSize: uint32(len(frame)) + flv.DataHeaderLength,
Timestamp: timeStamp,
TimestampExtended: flv.NoTimestampExtension,
FrameType: frameType,
Codec: flv.H264,
PacketType: packetType,
CompositionTime: 0,
Data: frame,
PrevTagSize: uint32(videoHeaderSize + len(frame)),
}
g.outputChan <- tag.Bytes()
}
// Do we even have some audio to send off ?
if g.audio {
// Not sure why but we need two audio tags for dummy silent audio
// TODO: create constants or SoundSize and SoundType parameters
tag := flv.AudioTag{
TagType: uint8(flv.AudioTagType),
DataSize: 7,
Timestamp: timeStamp,
TimestampExtended: flv.NoTimestampExtension,
SoundFormat: flv.AACAudioFormat,
SoundRate: 3,
SoundSize: true,
SoundType: true,
Data: dummyAudioTag1Data,
PrevTagSize: uint32(audioSize),
}
g.outputChan <- tag.Bytes()
tag = flv.AudioTag{
TagType: uint8(flv.AudioTagType),
DataSize: 21,
Timestamp: timeStamp,
TimestampExtended: flv.NoTimestampExtension,
SoundFormat: flv.AACAudioFormat,
SoundRate: 3,
SoundSize: true,
SoundType: true,
Data: dummyAudioTag2Data,
PrevTagSize: uint32(22),
}
g.outputChan <- tag.Bytes()
}
}
}
}

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@ -1,33 +0,0 @@
/*
NAME
RtpToTsConverter.go - provides utilities for the conversion of Rtp packets
to equivalent MpegTs packets.
DESCRIPTION
See Readme.md
AUTHOR
Saxon Nelson-Milton <saxon.milton@gmail.com>
LICENSE
RtpToTsConverter.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see [GNU licenses](http://www.gnu.org/licenses).
*/
package itut
func StartCode1() []byte { return []byte{0x00, 0x00, 0x01} }
func StartCode2() []byte { return []byte{0x00, 0x00, 0x00, 0x01} }
func AUD() []byte { return []byte{0x09, 0xF0} }

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@ -1,69 +0,0 @@
/*
NAME
MpegTs.go - provides a data structure intended to encapsulate the properties
of an MpegTs packet.
DESCRIPTION
See Readme.md
AUTHOR
Saxon Nelson-Milton <saxon.milton@gmail.com>
LICENSE
MpegTs.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see [GNU licenses](http://www.gnu.org/licenses).
*/
package mpegts
import "testing"
// Just ensure that we can create a byte slice with a mpegts packet correctly
func TestMpegTsToByteSlice(t *testing.T) {
payload := []byte{0x56, 0xA2, 0x78, 0x89, 0x67}
pcr := 100000 // => 100000
stuffing := make([]byte, 171)
for i := range stuffing {
stuffing[i] = 0xFF
}
tsPkt := MpegTsPacket{
PUSI: true,
PID: uint16(256),
AFC: byte(3),
AFL: 7 + 171,
CC: byte(6),
PCRF: true,
PCR: uint64(pcr),
Stuff: stuffing,
Payload: payload,
}
expectedOutput := []byte{0x47, 0x41, 0x00, 0x36, byte(178), 0x10}
for i := 40; i >= 0; i -= 8 {
expectedOutput = append(expectedOutput, byte(pcr>>uint(i)))
}
for i := 0; i < 171; i++ {
expectedOutput = append(expectedOutput, 0xFF)
}
expectedOutput = append(expectedOutput, payload...)
tsPktAsByteSlice, err := tsPkt.ToByteSlice()
if err != nil {
t.Errorf("Should not have got error!: %v", err)
}
for i := 0; i < 188; i++ {
if tsPktAsByteSlice[i] != expectedOutput[i] {
t.Errorf("Conversion to byte slice bad! Byte: %v Wanted: %v Got: %v", i, expectedOutput[i], tsPktAsByteSlice[i])
}
}
}

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@ -1,139 +0,0 @@
/*
NAME
h264.go
DESCRIPTION
See Readme.md
AUTHOR
Saxon Nelson-Milton <saxon@ausocean.org>
LICENSE
h264.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package parser
import (
"time"
"bitbucket.org/ausocean/av/itut"
)
const (
inputChanSize = 100000
outputBufferSize = 10000
)
// H264 provides properties and methods to allow for the parsing of a
// h264 stream - i.e. to allow extraction of the individual access units
type H264 struct {
inputBuffer []byte
isParsing bool
parserOutputChanRef chan []byte
userOutputChanRef chan []byte
inputChan chan byte
delay uint
}
// NewH264Parser returns an instance of the H264 struct
func NewH264Parser() (p *H264) {
p = new(H264)
p.isParsing = true
p.inputChan = make(chan byte, inputChanSize)
p.delay = 0
return
}
// Stop simply sets the isParsing flag to false to indicate to the parser that
// we don't want to interpret incoming data anymore - this will also make the
// parser jump out of the parse func
func (p *H264) Stop() {
p.isParsing = false
}
// Start starts the parse func as a goroutine so that incoming data is interpreted
func (p *H264) Start() {
p.isParsing = true
go p.parse()
}
// SetDelay sets a delay inbetween each buffer output. Useful if we're parsing
// a file but want to replicate the speed of incoming video frames from a
// camera
func (p *H264) SetDelay(delay uint) {
p.delay = delay
}
// InputChan returns a handle to the input channel of the parser
func (p *H264) InputChan() chan byte {
return p.inputChan
}
// OutputChan returns a handle to the output chan of the parser
func (p *H264) OutputChan() <-chan []byte {
return p.userOutputChanRef
}
// SetOutputChan sets the parser output chan to the passed output chan. This is
// useful if we want the parser output to go directly to a generator of some sort
// for packetization.
func (p *H264) SetOutputChan(o chan []byte) {
p.parserOutputChanRef = o
p.userOutputChanRef = o
}
// parse interprets an incoming h264 stream and extracts individual frames
// aka access units
func (p *H264) parse() {
outputBuffer := make([]byte, 0, outputBufferSize)
searchingForEnd := false
for p.isParsing {
var aByte uint8
if p.isParsing {
aByte = <-p.inputChan
} else {
return
}
outputBuffer = append(outputBuffer, aByte)
for i := 1; aByte == 0x00 && i != 4; i++ {
if p.isParsing {
aByte = <-p.inputChan
} else {
return
}
outputBuffer = append(outputBuffer, aByte)
if (aByte == 0x01 && i == 2) || (aByte == 0x01 && i == 3) {
if searchingForEnd {
output := append(append(itut.StartCode1(), itut.AUD()...), outputBuffer[:len(outputBuffer)-(i+1)]...)
time.Sleep(time.Duration(p.delay) * time.Millisecond)
p.parserOutputChanRef <- output
outputBuffer = outputBuffer[len(outputBuffer)-1-i:]
searchingForEnd = false
}
if p.isParsing {
aByte = <-p.inputChan
} else {
return
}
outputBuffer = append(outputBuffer, aByte)
if nalType := aByte & 0x1F; nalType == 1 || nalType == 5 || nalType == 8 || nalType == 7 {
searchingForEnd = true
}
}
}
}
}

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@ -1,87 +0,0 @@
/*
NAME
mjpeg.go
DESCRIPTION
See Readme.md
AUTHOR
Saxon Nelson-Milton <saxon@ausocean.org>
LICENSE
mjpeg.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package parser
const frameStartCode = 0xD8
type MJPEG struct {
inputBuffer []byte
isParsing bool
parserOutputChanRef chan []byte
userOutputChanRef chan []byte
inputChan chan byte
delay uint
}
func NewMJPEGParser(inputChanLen int) (p *MJPEG) {
p = new(MJPEG)
p.isParsing = true
p.inputChan = make(chan byte, inputChanLen)
return
}
func (p *MJPEG) Stop() {
p.isParsing = false
}
func (p *MJPEG) Start() {
go p.parse()
}
func (p *MJPEG) SetDelay(delay uint) {
p.delay = delay
}
func (p *MJPEG) InputChan() chan byte {
return p.inputChan
}
func (p *MJPEG) OutputChan() <-chan []byte {
return p.userOutputChanRef
}
func (p *MJPEG) SetOutputChan(o chan []byte) {
p.parserOutputChanRef = o
p.userOutputChanRef = o
}
func (p *MJPEG) parse() {
var outputBuffer []byte
for p.isParsing {
aByte := <-p.inputChan
outputBuffer = append(outputBuffer, aByte)
if aByte == 0xFF && len(outputBuffer) != 0 {
aByte := <-p.inputChan
outputBuffer = append(outputBuffer, aByte)
if aByte == frameStartCode {
p.parserOutputChanRef <- outputBuffer[:len(outputBuffer)-2]
outputBuffer = outputBuffer[len(outputBuffer)-2:]
}
}
}
}

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@ -1,50 +0,0 @@
/*
NAME
parser.go
DESCRIPTION
See Readme.md
AUTHOR
Saxon Nelson-Milton <saxon.milton@gmail.com>
LICENSE
parser.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licensesx).
*/
package parser
import (
"log"
"sync"
)
// h264 consts
const acceptedLength = 1000
var (
Info *log.Logger
mutex *sync.Mutex
)
type Parser interface {
Stop()
Start()
InputChan() chan byte
OutputChan() <-chan []byte
SetOutputChan(achan chan []byte)
SetDelay(delay uint)
}

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@ -1,127 +0,0 @@
/*
NAME
parser_test.go
DESCRIPTION
See Readme.md
AUTHOR
Saxon Nelson-Milton <saxon@ausocean.org>
LICENSE
parser_test.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package parser
import (
"fmt"
"io/ioutil"
"log"
"os"
"strconv"
"testing"
)
const (
mjpegInputFileName = "testInput/testInput.avi"
h264fName = "../../test/test-data/av/input/betterInput.h264"
nOfFrames = 4
outChanSize = 100
)
func TestH264Parser(t *testing.T) {
log.SetOutput(os.Stderr)
log.Println("Opening input file!")
inputFile, err := os.Open(h264fName)
if err != nil {
t.Errorf("Should not have got error opening file!")
return
}
log.Println("Reading data from file!")
data, err := ioutil.ReadAll(inputFile)
if err != nil {
t.Errorf("Should not have got read error!")
return
}
// Create 'parser' and start it up
log.Println("Creating parser!")
parser := NewH264Parser()
parser.SetOutputChan(make(chan []byte, outChanSize))
parser.Start()
for i, n := 0, 0; n <= nOfFrames; i++ {
select {
case parser.InputChan() <- data[i]:
case frame := <-parser.OutputChan():
path := fmt.Sprintf("testOutput/" + strconv.Itoa(n) + "h264_frame")
out, err := os.Create(path)
if err != nil {
t.Errorf("Unexpected error creating %q: %v", path, err)
return
}
out.Write(frame)
out.Close()
n++
default:
}
}
}
/*
func TestMJPEGParser(t *testing.T) {
log.Println("Opening input file!")
// Open the input file
inputFile, err := os.Open(testInputFileName)
if err != nil {
t.Errorf("Should not have got error opening file!")
}
log.Println("Getting file stats!")
stats, err := inputFile.Stat()
if err != nil {
t.Errorf("Could not get input file stats!")
return
}
log.Println("Creating space for file data!")
data := make([]byte, stats.Size())
_, err = inputFile.Read(data)
if err != nil {
t.Errorf("Should not have got read error!")
return
}
log.Println("Creating parser!")
parser := NewMJPEGParser(len(data) + 1)
parser.SetOutputChan(make(chan []byte, 10000))
parser.Start()
log.Printf("len(data): %v\n", len(data))
for i := range data {
parser.GetInputChan() <- data[i]
}
log.Println("Writing jpegs to files!")
for i := 0; len(parser.GetOutputChan()) > 0; i++ {
// Open a new output file
out, err := os.Create("testOutput/image" + strconv.Itoa(i) + ".jpeg")
if err != nil {
t.Errorf("Should not have got error creating output file!")
return
}
out.Write(<-parser.GetOutputChan())
out.Close()
}
}
*/

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@ -1,76 +0,0 @@
/*
NAME
MpegTs.go - provides a data structure intended to encapsulate the properties
of an MpegTs packet.
DESCRIPTION
See Readme.md
AUTHOR
Saxon Nelson-Milton <saxon.milton@gmail.com>
LICENSE
MpegTs.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package pes
import (
"testing"
)
const (
dataLength = 3 // bytes
)
func TestPesToByteSlice(t *testing.T) {
pesPkt := PESPacket{
StreamID: 0xE0, // StreamID
PDI: byte(2),
PTS: 100000,
HeaderLength: byte(10),
Stuff: []byte{0xFF, 0xFF},
Data: []byte{0xEA, 0x4B, 0x12},
}
pesExpectedOutput := []byte{
0x00, // packet start code prefix byte 1
0x00, // packet start code prefix byte 2
0x01, // packet start code prefix byte 3
0xE0, // stream ID
0x00, // PES Packet length byte 1
0x00, // PES packet length byte 2
0x80, // Marker bits,ScramblingControl, Priority, DAI, Copyright, Original
0x80, // PDI, ESCR, ESRate, DSMTrickMode, ACI, CRC, Ext
byte(10), // header length
0x21, // PCR byte 1
0x00, // pcr byte 2
0x07, // pcr byte 3
0x0D, // pcr byte 4
0x41, // pcr byte 5
0xFF, // Stuffing byte 1
0xFF, // stuffing byte 3
0xEA, // data byte 1
0x4B, // data byte 2
0x12, // data byte 3
}
pesPktAsByteSlice := pesPkt.ToByteSlice()
for ii := range pesPktAsByteSlice {
if pesPktAsByteSlice[ii] != pesExpectedOutput[ii] {
t.Errorf("Conversion to byte slice bad! Byte: %v Wanted: %v Got: %v",
ii, pesExpectedOutput[ii], pesPktAsByteSlice[ii])
}
}
}

45
revid/revid.go Executable file → Normal file
View File

@ -38,9 +38,11 @@ import (
"strconv"
"time"
"bitbucket.org/ausocean/av/generator"
"bitbucket.org/ausocean/av/parse"
"bitbucket.org/ausocean/av/rtmp"
"bitbucket.org/ausocean/av/stream"
"bitbucket.org/ausocean/av/stream/flv"
"bitbucket.org/ausocean/av/stream/mts"
"bitbucket.org/ausocean/iot/pi/netsender"
"bitbucket.org/ausocean/utils/ring"
)
@ -88,7 +90,7 @@ type Revid struct {
ringBuffer *ring.Buffer
config Config
isRunning bool
generator generator.Generator
encoder stream.Encoder
parse func(dst io.Writer, src io.Reader, delay time.Duration) error
cmd *exec.Cmd
inputReader io.ReadCloser
@ -208,12 +210,12 @@ func (r *Revid) reset(config Config) error {
return nil
case Mpegts:
r.Log(Info, "Using MPEGTS packetisation")
frameRate, _ := strconv.Atoi(r.config.FrameRate)
r.generator = generator.NewTsGenerator(float64(frameRate))
frameRate, _ := strconv.ParseFloat(r.config.FrameRate, 64)
r.encoder = mts.NewEncoder(frameRate)
case Flv:
r.Log(Info, "Using FLV packetisation")
frameRate, _ := strconv.Atoi(r.config.FrameRate)
r.generator = generator.NewFlvGenerator(true, true, frameRate)
r.encoder = flv.NewEncoder(true, true, frameRate)
}
// We have packetization of some sort, so we want to send data to Generator
// to perform packetization
@ -255,8 +257,6 @@ func (r *Revid) Start() {
go r.outputClips()
r.Log(Info, "Starting clip packing routine")
go r.packClips()
r.Log(Info, "Starting packetisation generator")
r.generator.Start()
r.Log(Info, "Setting up input and receiving content")
go r.setupInput()
}
@ -271,11 +271,6 @@ func (r *Revid) Stop() {
r.Log(Info, "Stopping revid!")
r.isRunning = false
r.Log(Info, "Stopping generator!")
if r.generator != nil {
r.generator.Stop()
}
r.Log(Info, "Killing input proccess!")
// If a cmd process is running, we kill!
if r.cmd != nil && r.cmd.Process != nil {
@ -284,17 +279,20 @@ func (r *Revid) Stop() {
}
// getFrameNoPacketization gets a frame directly from the revid output chan
// as we don't need to go through the generator with no packetization settings
// as we don't need to go through the encoder with no packetization settings
func (r *Revid) getFrameNoPacketization() []byte {
return <-r.outputChan
}
// getFramePacketization gets a frame from the generators output chan - the
// the generator being an mpegts or flv generator depending on the config
// the encoder being an mpegts or flv encoder depending on the config
func (r *Revid) getFramePacketization() []byte {
return <-r.generator.OutputChan()
return <-r.encoder.Stream()
}
// TODO(kortschak): Factor this out to an io.Writer type and remove the Stream chans.
// Also add a no-op encoder that handles non-packeted data.
//
// packClips takes data segments; whether that be tsPackets or mjpeg frames and
// packs them into clips consisting of the amount frames specified in the config
func (r *Revid) packClips() {
@ -304,7 +302,7 @@ func (r *Revid) packClips() {
select {
// TODO: This is temporary, need to work out how to make this work
// for cases when there is not packetisation.
case frame := <-r.generator.OutputChan():
case frame := <-r.encoder.Stream():
lenOfFrame := len(frame)
if lenOfFrame > ringBufferElementSize {
r.Log(Warning, fmt.Sprintf("Frame was too big: %v bytes, getting another one!", lenOfFrame))
@ -475,7 +473,7 @@ func (r *Revid) startRaspivid() error {
r.inputReader = stdout
go func() {
r.Log(Info, "Reading camera data!")
r.parse(chunkWriter(r.generator.InputChan()), r.inputReader, 0)
r.parse(chunkWriter{r.encoder}, r.inputReader, 0)
r.Log(Info, "Not trying to read from camera anymore!")
}()
return nil
@ -498,14 +496,19 @@ func (r *Revid) setupInputForFile() error {
defer f.Close()
// TODO(kortschak): Maybe we want a context.Context-aware parser that we can stop.
return r.parse(chunkWriter(r.generator.InputChan()), f, delay)
return r.parse(chunkWriter{r.encoder}, f, delay)
}
// TODO(kortschak): Remove this type and revise the signature of
// the parsers to accept an stream.Encoder.
//
// chunkWriter is a shim between the new function-based approach
// and the old flow-based approach.
type chunkWriter chan []byte
type chunkWriter struct {
stream.Encoder
}
func (w chunkWriter) Write(b []byte) (int, error) {
w <- b
return len(b), nil
err := w.Encoder.Encode(b)
return len(b), err
}

View File

@ -1,6 +1,6 @@
/*
NAME
generator.go
encoding.go
DESCRIPTION
See Readme.md
@ -9,7 +9,7 @@ AUTHOR
Saxon Nelson-Milton <saxon@ausocean.org>
LICENSE
generator.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
encoding.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
@ -25,11 +25,9 @@ LICENSE
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package generator
package stream
type Generator interface {
InputChan() chan []byte
OutputChan() <-chan []byte
Start()
Stop()
type Encoder interface {
Encode([]byte) error
Stream() <-chan []byte
}

260
stream/flv/encoder.go Normal file
View File

@ -0,0 +1,260 @@
/*
NAME
flv_generator.go
DESCRIPTION
See Readme.md
AUTHOR
Dan Kortschak <dan@ausocean.org>
Saxon Nelson-Milton <saxon@ausocean.org>
LICENSE
flv_generator.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package flv
import "time"
const (
inputChanLength = 500
outputChanLength = 500
audioSize = 18
videoHeaderSize = 16
)
// Data representing silent audio (required for youtube)
var (
dummyAudioTag1Data = []byte{
0x00, 0x12, 0x08, 0x56, 0xe5, 0x00,
}
dummyAudioTag2Data = []byte{
0x01, 0xdc, 0x00, 0x4c, 0x61, 0x76, 0x63, 0x35, 0x38,
0x2e, 0x36, 0x2e, 0x31, 0x30, 0x32, 0x00, 0x02, 0x30,
0x40, 0x0e,
}
)
// Encoder provides properties required for the generation of flv video
// from raw video data
type Encoder struct {
fps int
stream chan []byte
audio bool
video bool
lastTagSize int
header Header
startTime time.Time
firstTag bool
isGenerating bool
}
// NewEncoder retuns a new FLV encoder.
func NewEncoder(audio, video bool, fps int) *Encoder {
e := Encoder{
fps: fps,
audio: audio,
video: video,
stream: make(chan []byte, outputChanLength),
firstTag: true,
}
e.stream <- e.HeaderBytes()
return &e
}
// HeaderBytes returns the a
func (e *Encoder) HeaderBytes() []byte {
header := Header{
HasAudio: e.audio,
HasVideo: e.video,
}
return header.Bytes()
}
// Stream returns a channel of streaming packets.
func (e *Encoder) Stream() <-chan []byte {
return e.stream
}
// getNextTimestamp generates and returns the next timestamp based on current time
func (e *Encoder) getNextTimestamp() (timestamp uint32) {
if e.firstTag {
e.startTime = time.Now()
e.firstTag = false
return 0
}
return uint32(time.Now().Sub(e.startTime).Seconds() * float64(1000))
}
// http://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-H.264-200305-S!!PDF-E&type=items
// Table 7-1 NAL unit type codes
const (
nonIdrPic = 1
idrPic = 5
suppEnhInf = 6
seqParamSet = 7
paramSet = 8
)
// isKeyFrame returns true if the passed frame data represents that of a keyframe
// FIXME(kortschak): Clarify and document the logic of this functions.
func isKeyFrame(frame []byte) bool {
sc := frameScanner{buf: frame}
for {
b, ok := sc.readByte()
if !ok {
return false
}
for i := 1; b == 0x00 && i < 4; i++ {
b, ok = sc.readByte()
if !ok {
return false
}
if b != 0x01 || (i != 3 && i != 2) {
continue
}
b, ok = sc.readByte()
if !ok {
return false
}
switch nalTyp := b & 0x1f; nalTyp {
case idrPic, suppEnhInf:
return true
case nonIdrPic:
return false
}
}
}
return false
}
// isSequenceHeader returns true if the passed frame data represents that of a
// a sequence header.
// FIXME(kortschak): Clarify and document the logic of this functions.
func isSequenceHeader(frame []byte) bool {
sc := frameScanner{buf: frame}
for {
b, ok := sc.readByte()
if !ok {
return false
}
for i := 1; b == 0x00 && i != 4; i++ {
b, ok = sc.readByte()
if !ok {
return false
}
if b != 0x01 || (i != 2 && i != 3) {
continue
}
b, ok = sc.readByte()
if !ok {
return false
}
switch nalTyp := b & 0x1f; nalTyp {
case suppEnhInf, seqParamSet, paramSet:
return true
case nonIdrPic, idrPic:
return false
}
}
}
}
type frameScanner struct {
off int
buf []byte
}
func (s *frameScanner) readByte() (b byte, ok bool) {
if s.off >= len(s.buf) {
return 0, false
}
b = s.buf[s.off]
s.off++
return b, true
}
// generate takes in raw video data from the input chan and packetises it into
// flv tags, which are then passed to the output channel.
func (e *Encoder) Encode(frame []byte) error {
var frameType byte
var packetType byte
timeStamp := e.getNextTimestamp()
// Do we have video to send off?
if e.video {
if isKeyFrame(frame) {
frameType = KeyFrameType
} else {
frameType = InterFrameType
}
if isSequenceHeader(frame) {
packetType = SequenceHeader
} else {
packetType = AVCNALU
}
tag := VideoTag{
TagType: uint8(VideoTagType),
DataSize: uint32(len(frame)) + DataHeaderLength,
Timestamp: timeStamp,
TimestampExtended: NoTimestampExtension,
FrameType: frameType,
Codec: H264,
PacketType: packetType,
CompositionTime: 0,
Data: frame,
PrevTagSize: uint32(videoHeaderSize + len(frame)),
}
e.stream <- tag.Bytes()
}
// Do we even have some audio to send off ?
if e.audio {
// Not sure why but we need two audio tags for dummy silent audio
// TODO: create constants or SoundSize and SoundType parameters
tag := AudioTag{
TagType: uint8(AudioTagType),
DataSize: 7,
Timestamp: timeStamp,
TimestampExtended: NoTimestampExtension,
SoundFormat: AACAudioFormat,
SoundRate: 3,
SoundSize: true,
SoundType: true,
Data: dummyAudioTag1Data,
PrevTagSize: uint32(audioSize),
}
e.stream <- tag.Bytes()
tag = AudioTag{
TagType: uint8(AudioTagType),
DataSize: 21,
Timestamp: timeStamp,
TimestampExtended: NoTimestampExtension,
SoundFormat: AACAudioFormat,
SoundRate: 3,
SoundSize: true,
SoundType: true,
Data: dummyAudioTag2Data,
PrevTagSize: uint32(22),
}
e.stream <- tag.Bytes()
}
return nil
}

View File

@ -1,6 +1,6 @@
/*
NAME
mpegts_generator.go
encoder.go
DESCRIPTION
See Readme.md
@ -10,7 +10,7 @@ AUTHOR
Saxon Nelson-Milton <saxon@ausocean.org>
LICENSE
mpegts_generator.go is Copyright (C) 2017-2018 the Australian Ocean Lab (AusOcean)
encoder.go is Copyright (C) 2017-2018 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
@ -26,7 +26,7 @@ LICENSE
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package generator
package mts
import (
"encoding/binary"
@ -34,8 +34,7 @@ import (
"math/bits"
"time"
"bitbucket.org/ausocean/av/mpegts"
"bitbucket.org/ausocean/av/pes"
"bitbucket.org/ausocean/av/stream/mts/pes"
)
const psiPacketSize = 184
@ -155,10 +154,9 @@ const (
pcrFreq = 90000 // Hz
)
// tsGenerator encapsulates properties of an mpegts generator.
type tsGenerator struct {
outputChan chan []byte
nalInputChan chan []byte
// Encoder encapsulates properties of an mpegts generator.
type Encoder struct {
stream chan []byte
clock time.Duration
frameInterval time.Duration
@ -167,11 +165,10 @@ type tsGenerator struct {
continuity map[int]byte
}
// NewTsGenerator returns an instance of the tsGenerator struct
func NewTsGenerator(fps float64) (g *tsGenerator) {
return &tsGenerator{
outputChan: make(chan []byte, 1),
nalInputChan: make(chan []byte, 1),
// NewEncoder returns an Encoder with the specified frame rate.
func NewEncoder(fps float64) *Encoder {
return &Encoder{
stream: make(chan []byte, 1),
frameInterval: time.Duration(float64(time.Second) / fps),
ptsOffset: ptsOffset,
@ -184,24 +181,9 @@ func NewTsGenerator(fps float64) (g *tsGenerator) {
}
}
// Start is called when we would like generation to begin, i.e. we would like
// the generator to start taking input data and creating mpegts packets
func (g *tsGenerator) Start() {
go g.generate()
}
func (g *tsGenerator) Stop() {}
// InputChan returns a handle to the nalInputChan (inputChan) so that nal units
// can be passed to the generator and processed
func (g *tsGenerator) InputChan() chan []byte {
return g.nalInputChan
}
// OutputChan returns a handle to the generator output chan where the mpegts
// packets will show up once ready to go
func (g *tsGenerator) OutputChan() <-chan []byte {
return g.outputChan
// Stream returns a channel of streaming packets.
func (e *Encoder) Stream() <-chan []byte {
return e.stream
}
const (
@ -216,86 +198,84 @@ const (
// generate handles the incoming data and generates equivalent mpegts packets -
// sending them to the output channel
func (g *tsGenerator) generate() {
for {
nalu := <-g.nalInputChan
// Write PAT
patPkt := mpegts.Packet{
PUSI: true,
PID: patPid,
CC: g.ccFor(patPid),
AFC: hasPayload,
Payload: patTable,
}
g.outputChan <- patPkt.Bytes()
// Write PMT.
pmtPkt := mpegts.Packet{
PUSI: true,
PID: pmtPid,
CC: g.ccFor(pmtPid),
AFC: hasPayload,
Payload: pmtTable,
}
g.outputChan <- pmtPkt.Bytes()
// Prepare PES data.
pesPkt := pes.Packet{
StreamID: streamID,
PDI: hasPTS,
PTS: g.pts(),
Data: nalu,
HeaderLength: 5,
}
buf := pesPkt.Bytes()
pusi := true
for len(buf) != 0 {
pkt := mpegts.Packet{
PUSI: pusi,
PID: videoPid,
RAI: pusi,
CC: g.ccFor(videoPid),
AFC: hasAdaptationField | hasPayload,
PCRF: pusi,
}
n := pkt.FillPayload(buf)
buf = buf[n:]
if pusi {
// If the packet has a Payload Unit Start Indicator
// flag set then we need to write a PCR.
pkt.PCR = g.pcr()
pusi = false
}
g.outputChan <- pkt.Bytes()
}
g.tick()
func (e *Encoder) Encode(nalu []byte) error {
// Write PAT
patPkt := Packet{
PUSI: true,
PID: patPid,
CC: e.ccFor(patPid),
AFC: hasPayload,
Payload: patTable,
}
e.stream <- patPkt.Bytes()
// Write PMT.
pmtPkt := Packet{
PUSI: true,
PID: pmtPid,
CC: e.ccFor(pmtPid),
AFC: hasPayload,
Payload: pmtTable,
}
e.stream <- pmtPkt.Bytes()
// Prepare PES data.
pesPkt := pes.Packet{
StreamID: streamID,
PDI: hasPTS,
PTS: e.pts(),
Data: nalu,
HeaderLength: 5,
}
buf := pesPkt.Bytes()
pusi := true
for len(buf) != 0 {
pkt := Packet{
PUSI: pusi,
PID: videoPid,
RAI: pusi,
CC: e.ccFor(videoPid),
AFC: hasAdaptationField | hasPayload,
PCRF: pusi,
}
n := pkt.FillPayload(buf)
buf = buf[n:]
if pusi {
// If the packet has a Payload Unit Start Indicator
// flag set then we need to write a PCR.
pkt.PCR = e.pcr()
pusi = false
}
e.stream <- pkt.Bytes()
}
e.tick()
return nil
}
// tick advances the clock one frame interval.
func (g *tsGenerator) tick() {
g.clock += g.frameInterval
func (e *Encoder) tick() {
e.clock += e.frameInterval
}
// pts retuns the current presentation timestamp.
func (g *tsGenerator) pts() uint64 {
return uint64((g.clock + g.ptsOffset).Seconds() * pcrFreq)
func (e *Encoder) pts() uint64 {
return uint64((e.clock + e.ptsOffset).Seconds() * pcrFreq)
}
// pcr returns the current program clock reference.
func (g *tsGenerator) pcr() uint64 {
return uint64(g.clock.Seconds() * pcrFreq)
func (e *Encoder) pcr() uint64 {
return uint64(e.clock.Seconds() * pcrFreq)
}
// ccFor returns the next continuity counter for pid.
func (g *tsGenerator) ccFor(pid int) byte {
cc := g.continuity[pid]
func (e *Encoder) ccFor(pid int) byte {
cc := e.continuity[pid]
const continuityCounterMask = 0xf
g.continuity[pid] = (cc + 1) & continuityCounterMask
e.continuity[pid] = (cc + 1) & continuityCounterMask
return cc
}

View File

@ -1,6 +1,6 @@
/*
NAME
MpegTs.go - provides a data structure intended to encapsulate the properties
mpegts.go - provides a data structure intended to encapsulate the properties
of an MpegTs packet and also functions to allow manipulation of these packets.
DESCRIPTION
@ -10,7 +10,7 @@ AUTHOR
Saxon A. Nelson-Milton <saxon.milton@gmail.com>
LICENSE
MpegTs.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
mpegts.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
@ -26,7 +26,7 @@ LICENSE
along with revid in gpl.txt. If not, see [GNU licenses](http://www.gnu.org/licenses).
*/
package mpegts
package mts
const (
mpegTsSize = 188

View File

@ -0,0 +1,74 @@
/*
NAME
mpegts_test.go
DESCRIPTION
See Readme.md
AUTHOR
Dan Kortschak <dan@ausocean.org>
Saxon Nelson-Milton <saxon.milton@gmail.com>
LICENSE
mpegts_test.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package pes
import (
"reflect"
"testing"
)
const (
dataLength = 3 // bytes
)
func TestPesToByteSlice(t *testing.T) {
pkt := Packet{
StreamID: 0xE0, // StreamID
PDI: byte(2),
PTS: 100000,
HeaderLength: byte(10),
Stuff: []byte{0xFF, 0xFF},
Data: []byte{0xEA, 0x4B, 0x12},
}
got := pkt.Bytes()
want := []byte{
0x00, // packet start code prefix byte 1
0x00, // packet start code prefix byte 2
0x01, // packet start code prefix byte 3
0xE0, // stream ID
0x00, // PES Packet length byte 1
0x00, // PES packet length byte 2
0x80, // Marker bits,ScramblingControl, Priority, DAI, Copyright, Original
0x80, // PDI, ESCR, ESRate, DSMTrickMode, ACI, CRC, Ext
10, // header length
0x21, // PCR byte 1
0x00, // pcr byte 2
0x07, // pcr byte 3
0x0D, // pcr byte 4
0x41, // pcr byte 5
0xFF, // Stuffing byte 1
0xFF, // stuffing byte 3
0xEA, // data byte 1
0x4B, // data byte 2
0x12, // data byte 3
}
if !reflect.DeepEqual(got, want) {
t.Errorf("unexpected packet encoding:\ngot: %#v\nwant:%#v", got, want)
}
}