av/revid/revid.go

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/*
NAME
revid.go
AUTHORS
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Saxon A. Nelson-Milton <saxon@ausocean.org>
Alan Noble <alan@ausocean.org>
Dan Kortschak <dan@ausocean.org>
Trek Hopton <trek@ausocean.org>
LICENSE
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revid 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
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
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for more details.
You should have received a copy of the GNU General Public License
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in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
// Package revid provides an API for reading, transcoding, and writing audio/video streams and files.
package revid
import (
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"errors"
"fmt"
"io"
"os/exec"
"strconv"
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"strings"
"sync"
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"time"
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"bitbucket.org/ausocean/av/codec/codecutil"
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"bitbucket.org/ausocean/av/codec/h264"
"bitbucket.org/ausocean/av/codec/h265"
"bitbucket.org/ausocean/av/codec/mjpeg"
"bitbucket.org/ausocean/av/codec/pcm"
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"bitbucket.org/ausocean/av/container/flv"
"bitbucket.org/ausocean/av/container/mts"
"bitbucket.org/ausocean/av/device"
"bitbucket.org/ausocean/av/device/alsa"
"bitbucket.org/ausocean/av/device/file"
"bitbucket.org/ausocean/av/device/geovision"
"bitbucket.org/ausocean/av/device/raspivid"
"bitbucket.org/ausocean/av/device/webcam"
"bitbucket.org/ausocean/av/revid/config"
"bitbucket.org/ausocean/iot/pi/netsender"
"bitbucket.org/ausocean/utils/ioext"
"bitbucket.org/ausocean/utils/logger"
"bitbucket.org/ausocean/utils/ring"
)
// Ring buffer defaults.
const (
// MTS ring buffer defaults.
defaultMTSRBSize = 1000
defaultMTSRBElementSize = 100000
defaultMTSRBWriteTimeout = 5
// RTMP ring buffer defaults.
defaultRTMPRBSize = 1000
defaultRTMPRBElementSize = 300000
defaultRTMPRBWriteTimeout = 5
)
// RTMP connection properties.
const (
rtmpConnectionMaxTries = 5
rtmpConnectionTimeout = 10
)
const pkg = "revid: "
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type Logger interface {
SetLevel(int8)
Log(level int8, message string, params ...interface{})
}
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// Revid provides methods to control a revid session; providing methods
// to start, stop and change the state of an instance using the Config struct.
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type Revid struct {
// config holds the Revid configuration.
// For historical reasons it also handles logging.
// FIXME(kortschak): The relationship of concerns
// in config/ns is weird.
cfg config.Config
// ns holds the netsender.Sender responsible for HTTP.
ns *netsender.Sender
// input will capture audio or video from which we can read data.
input device.AVDevice
// closeInput holds the cleanup function return from setupInput and is called
// in Revid.Stop().
closeInput func() error
// cmd is the exec'd process that may be used to produce
// the input stream.
// FIXME(kortschak): This should not exist. Replace this
// with a context.Context cancellation.
cmd *exec.Cmd
// lexTo, encoder and packer handle transcoding the input stream.
lexTo func(dest io.Writer, src io.Reader, delay time.Duration) error
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// encoders will hold the multiWriteCloser that writes to encoders from the lexer.
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encoders io.WriteCloser
// running is used to keep track of revid's running state between methods.
running bool
// mu is used to protect isRunning during concurrent use.
mu sync.Mutex
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// wg will be used to wait for any processing routines to finish.
wg sync.WaitGroup
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// err will channel errors from revid routines to the handle errors routine.
err chan error
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}
// New returns a pointer to a new Revid with the desired configuration, and/or
// an error if construction of the new instance was not successful.
func New(c config.Config, ns *netsender.Sender) (*Revid, error) {
r := Revid{ns: ns, err: make(chan error)}
err := r.setConfig(c)
if err != nil {
return nil, fmt.Errorf("could not set config, failed with error: %v", err)
}
r.cfg.Logger.SetLevel(c.LogLevel)
go r.handleErrors()
return &r, nil
}
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// Config returns a copy of revids current config.
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//
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// Config is not safe for concurrent use.
func (r *Revid) Config() config.Config {
return r.cfg
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}
// TODO(Saxon): put more thought into error severity and how to handle these.
func (r *Revid) handleErrors() {
for {
err := <-r.err
if err != nil {
r.cfg.Logger.Log(logger.Error, pkg+"async error", "error", err.Error())
}
}
}
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// Bitrate returns the result of the most recent bitrate check.
//
// TODO: get this working again.
func (r *Revid) Bitrate() int {
return -1
}
// reset swaps the current config of a Revid with the passed
// configuration; checking validity and returning errors if not valid. It then
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// sets up the data pipeline accordingly to this configuration.
func (r *Revid) reset(c config.Config) error {
err := r.setConfig(c)
if err != nil {
return err
}
r.cfg.Logger.SetLevel(c.LogLevel)
err = r.setupPipeline(
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func(dst io.WriteCloser, fps float64) (io.WriteCloser, error) {
var st int
var encOptions []func(*mts.Encoder) error
switch r.cfg.Input {
case config.InputRaspivid:
switch r.cfg.InputCodec {
case codecutil.H264:
st = mts.EncodeH264
case codecutil.MJPEG:
st = mts.EncodeMJPEG
encOptions = append(encOptions, mts.PacketBasedPSI(int(r.cfg.MinFrames)))
default:
panic("unknown input codec for raspivid input")
}
case config.InputFile, config.InputV4L:
st = mts.EncodeH264
case config.InputRTSP:
switch r.cfg.InputCodec {
case codecutil.H265:
st = mts.EncodeH265
case codecutil.H264:
st = mts.EncodeH264
case codecutil.MJPEG:
st = mts.EncodeMJPEG
encOptions = append(encOptions, mts.PacketBasedPSI(int(r.cfg.MinFrames)))
default:
panic("unknown input codec for RTSP input")
}
case config.InputAudio:
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st = mts.EncodeAudio
default:
panic("unknown input type")
}
return mts.NewEncoder(dst, float64(fps), st, encOptions...)
},
func(dst io.WriteCloser, fps int) (io.WriteCloser, error) {
return flv.NewEncoder(dst, true, true, fps)
},
ioext.MultiWriteCloser,
)
if err != nil {
return err
}
return nil
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}
// setConfig takes a config, checks it's validity and then replaces the current
// revid config.
func (r *Revid) setConfig(config config.Config) error {
r.cfg.Logger = config.Logger
err := config.Validate()
if err != nil {
return errors.New("Config struct is bad: " + err.Error())
}
r.cfg = config
return nil
}
// setupPipeline constructs the revid dataPipeline. Inputs, encoders and
// senders are created and linked based on the current revid config.
//
// mtsEnc and flvEnc will be called to obtain an mts encoder and flv encoder
// respectively. multiWriter will be used to create an ioext.multiWriteCloser
// so that encoders can write to multiple senders.
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func (r *Revid) setupPipeline(mtsEnc func(dst io.WriteCloser, rate float64) (io.WriteCloser, error), flvEnc func(dst io.WriteCloser, rate int) (io.WriteCloser, error), multiWriter func(...io.WriteCloser) io.WriteCloser) error {
// encoders will hold the encoders that are required for revid's current
// configuration.
var encoders []io.WriteCloser
// mtsSenders will hold the senders the require MPEGTS encoding, and flvSenders
// will hold senders that require FLV encoding.
var mtsSenders, flvSenders []io.WriteCloser
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// We will go through our outputs and create the corresponding senders to add
// to mtsSenders if the output requires MPEGTS encoding, or flvSenders if the
// output requires FLV encoding.
var w io.WriteCloser
for _, out := range r.cfg.Outputs {
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switch out {
case config.OutputHTTP:
w = newMtsSender(
newHttpSender(r.ns, r.cfg.Logger.Log),
r.cfg.Logger.Log,
ring.NewBuffer(r.cfg.MTSRBSize, r.cfg.MTSRBElementSize, time.Duration(r.cfg.MTSRBWriteTimeout)*time.Second),
r.cfg.ClipDuration,
)
mtsSenders = append(mtsSenders, w)
case config.OutputRTP:
w, err := newRtpSender(r.cfg.RTPAddress, r.cfg.Logger.Log, r.cfg.FrameRate)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"rtp connect error", "error", err.Error())
}
mtsSenders = append(mtsSenders, w)
case config.OutputFile:
w, err := newFileSender(r.cfg.OutputPath)
if err != nil {
return err
}
mtsSenders = append(mtsSenders, w)
case config.OutputRTMP:
w, err := newRtmpSender(
r.cfg.RTMPURL,
rtmpConnectionTimeout,
rtmpConnectionMaxTries,
ring.NewBuffer(r.cfg.RTMPRBSize, r.cfg.RTMPRBElementSize, time.Duration(r.cfg.RTMPRBWriteTimeout)*time.Second),
r.cfg.Logger.Log,
)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"rtmp connect error", "error", err.Error())
}
flvSenders = append(flvSenders, w)
}
}
// If we have some senders that require MPEGTS encoding then add an MPEGTS
// encoder to revid's encoder slice, and give this encoder the mtsSenders
// as a destination.
if len(mtsSenders) != 0 {
mw := multiWriter(mtsSenders...)
e, _ := mtsEnc(mw, r.cfg.WriteRate)
encoders = append(encoders, e)
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}
// If we have some senders that require FLV encoding then add an FLV
// encoder to revid's encoder slice, and give this encoder the flvSenders
// as a destination.
if len(flvSenders) != 0 {
mw := multiWriter(flvSenders...)
e, err := flvEnc(mw, int(r.cfg.FrameRate))
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if err != nil {
return err
}
encoders = append(encoders, e)
}
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r.encoders = multiWriter(encoders...)
switch r.cfg.Input {
case config.InputRaspivid:
r.input = raspivid.New(r.cfg.Logger)
switch r.cfg.InputCodec {
case codecutil.H264:
r.lexTo = h264.Lex
case codecutil.MJPEG:
r.lexTo = mjpeg.Lex
}
case config.InputV4L:
r.input = webcam.New(r.cfg.Logger)
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r.lexTo = h264.Lex
case config.InputFile:
r.input = file.New()
case config.InputRTSP:
r.input = geovision.New(r.cfg.Logger)
switch r.cfg.InputCodec {
case codecutil.H264:
r.lexTo = h264.NewExtractor().Extract
case codecutil.H265:
r.lexTo = h265.NewLexer(false).Lex
case codecutil.MJPEG:
panic("not implemented")
}
case config.InputAudio:
mts.Meta.Add("sampleRate", strconv.Itoa(r.cfg.SampleRate))
mts.Meta.Add("channels", strconv.Itoa(r.cfg.Channels))
mts.Meta.Add("period", fmt.Sprintf("%.6f", r.cfg.RecPeriod))
mts.Meta.Add("bitDepth", strconv.Itoa(r.cfg.BitDepth))
switch r.cfg.InputCodec {
case codecutil.PCM:
mts.Meta.Add("codec", "pcm")
case codecutil.ADPCM:
mts.Meta.Add("codec", "adpcm")
default:
r.cfg.Logger.Log(logger.Fatal, pkg+"no audio codec set in config")
}
r.input = alsa.New(r.cfg.Logger)
l, err := codecutil.NewByteLexer(pcm.DataSize(r.cfg.SampleRate, r.cfg.Channels, r.cfg.BitDepth, r.cfg.RecPeriod, r.cfg.InputCodec))
if err != nil {
return err
}
r.lexTo = l.Lex
}
// Configure the input device. We know that defaults are set, so no need to
// return error, but we should log.
err := r.input.Set(r.cfg)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"errors from configuring input device", "errors", err)
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}
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return nil
}
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// Start invokes a Revid to start processing video from a defined input
// and packetising (if theres packetization) to a defined output.
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//
// Start is safe for concurrent use.
func (r *Revid) Start() error {
if r.IsRunning() {
r.cfg.Logger.Log(logger.Warning, pkg+"start called, but revid already running")
return nil
}
r.mu.Lock()
defer r.mu.Unlock()
r.cfg.Logger.Log(logger.Info, pkg+"starting Revid")
err := r.reset(r.cfg)
if err != nil {
r.Stop()
return err
}
err = r.input.Start()
if err != nil {
return fmt.Errorf("could not start input device: %w", err)
}
r.wg.Add(1)
go r.processFrom(r.input, 0)
r.running = true
return nil
}
// Stop closes down the pipeline. This closes encoders and sender output routines,
// connections, and/or files.
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//
// Stop is safe for concurrent use.
func (r *Revid) Stop() {
if !r.IsRunning() {
r.cfg.Logger.Log(logger.Warning, pkg+"stop called but revid isn't running")
return
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}
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r.mu.Lock()
defer r.mu.Unlock()
err := r.input.Stop()
if err != nil {
r.cfg.Logger.Log(logger.Error, pkg+"could not stop input", "error", err.Error())
}
r.cfg.Logger.Log(logger.Info, pkg+"closing pipeline")
err = r.encoders.Close()
if err != nil {
r.cfg.Logger.Log(logger.Error, pkg+"failed to close pipeline", "error", err.Error())
}
r.cfg.Logger.Log(logger.Info, pkg+"closed pipeline")
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if r.cmd != nil && r.cmd.Process != nil {
r.cfg.Logger.Log(logger.Info, pkg+"killing input proccess")
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r.cmd.Process.Kill()
}
r.cfg.Logger.Log(logger.Info, pkg+"waiting for routines to close")
r.wg.Wait()
r.cfg.Logger.Log(logger.Info, pkg+"revid stopped")
r.running = false
}
func (r *Revid) IsRunning() bool {
r.mu.Lock()
defer r.mu.Unlock()
return r.running
}
// Update takes a map of variables and their values and edits the current config
// if the variables are recognised as valid parameters.
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//
// Update is safe for concurrent use.
func (r *Revid) Update(vars map[string]string) error {
if r.IsRunning() {
r.Stop()
}
r.mu.Lock()
defer r.mu.Unlock()
//look through the vars and update revid where needed
for key, value := range vars {
switch key {
case "Input":
v, ok := map[string]uint8{"raspivid": config.InputRaspivid, "rtsp": config.InputRTSP, "v4l": config.InputV4L}[strings.ToLower(value)]
if !ok {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid input var", "value", value)
break
}
r.cfg.Input = v
case "Saturation":
s, err := strconv.ParseInt(value, 10, 0)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid saturation param", "value", value)
break
}
r.cfg.Saturation = int(s)
case "Brightness":
b, err := strconv.ParseUint(value, 10, 0)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid brightness param", "value", value)
break
}
r.cfg.Brightness = uint(b)
case "Exposure":
r.cfg.Exposure = value
case "AutoWhiteBalance":
r.cfg.AutoWhiteBalance = value
case "InputCodec":
switch value {
case "H264":
r.cfg.InputCodec = codecutil.H264
case "MJPEG":
r.cfg.InputCodec = codecutil.MJPEG
default:
r.cfg.Logger.Log(logger.Warning, pkg+"invalid InputCodec variable value", "value", value)
}
case "Output":
outputs := strings.Split(value, ",")
r.cfg.Outputs = make([]uint8, len(outputs))
for i, output := range outputs {
switch output {
case "File":
r.cfg.Outputs[i] = config.OutputFile
case "Http":
r.cfg.Outputs[i] = config.OutputHTTP
case "Rtmp":
r.cfg.Outputs[i] = config.OutputRTMP
case "Rtp":
r.cfg.Outputs[i] = config.OutputRTP
default:
r.cfg.Logger.Log(logger.Warning, pkg+"invalid output param", "value", value)
continue
}
}
case "RtmpUrl":
r.cfg.RTMPURL = value
case "RtpAddress":
r.cfg.RTPAddress = value
case "Bitrate":
v, err := strconv.ParseUint(value, 10, 0)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid framerate param", "value", value)
break
}
r.cfg.Bitrate = uint(v)
case "OutputPath":
r.cfg.OutputPath = value
case "InputPath":
r.cfg.InputPath = value
case "Height":
h, err := strconv.ParseUint(value, 10, 0)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid height param", "value", value)
break
}
r.cfg.Height = uint(h)
case "Width":
w, err := strconv.ParseUint(value, 10, 0)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid width param", "value", value)
break
}
r.cfg.Width = uint(w)
case "FrameRate":
v, err := strconv.ParseUint(value, 10, 0)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid framerate param", "value", value)
break
}
r.cfg.FrameRate = uint(v)
case "Rotation":
v, err := strconv.ParseUint(value, 10, 0)
if err != nil || v > 359 {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid rotation param", "value", value)
break
}
r.cfg.Rotation = uint(v)
case "HttpAddress":
r.cfg.HTTPAddress = value
case "Quantization":
v, err := strconv.Atoi(value)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid quantization param", "value", v)
break
}
r.cfg.Quantization = uint(v)
case "MinFrames":
v, err := strconv.Atoi(value)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid MinFrames param", "value", value)
break
}
r.cfg.MinFrames = uint(v)
case "ClipDuration":
v, err := strconv.Atoi(value)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid ClipDuration param", "value", value)
break
}
r.cfg.ClipDuration = time.Duration(v) * time.Second
case "HorizontalFlip":
switch strings.ToLower(value) {
case "true":
r.cfg.FlipHorizontal = true
case "false":
r.cfg.FlipHorizontal = false
default:
r.cfg.Logger.Log(logger.Warning, pkg+"invalid HorizontalFlip param", "value", value)
}
case "VerticalFlip":
switch strings.ToLower(value) {
case "true":
r.cfg.FlipVertical = true
case "false":
r.cfg.FlipVertical = false
default:
r.cfg.Logger.Log(logger.Warning, pkg+"invalid VerticalFlip param", "value", value)
}
case "BurstPeriod":
v, err := strconv.ParseUint(value, 10, 0)
if err != nil {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid BurstPeriod param", "value", value)
break
}
r.cfg.BurstPeriod = uint(v)
case "Logging":
switch value {
case "Debug":
r.cfg.LogLevel = logger.Debug
case "Info":
r.cfg.LogLevel = logger.Info
case "Warning":
r.cfg.LogLevel = logger.Warning
case "Error":
r.cfg.LogLevel = logger.Error
case "Fatal":
r.cfg.LogLevel = logger.Fatal
default:
r.cfg.Logger.Log(logger.Warning, pkg+"invalid Logging param", "value", value)
}
case "RTMPRBSize":
v, err := strconv.Atoi(value)
if err != nil || v < 0 {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid RTMPRBSize var", "value", value)
break
}
r.cfg.RTMPRBSize = v
case "RTMPRBElementSize":
v, err := strconv.Atoi(value)
if err != nil || v < 0 {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid RTMPRBElementSize var", "value", value)
break
}
r.cfg.RTMPRBElementSize = v
case "RTMPRBWriteTimeout":
v, err := strconv.Atoi(value)
if err != nil || v <= 0 {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid RTMPRBWriteTimeout var", "value", value)
break
}
r.cfg.RTMPRBWriteTimeout = v
case "MTSRBSize":
v, err := strconv.Atoi(value)
if err != nil || v < 0 {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid MTSRBSize var", "value", value)
break
}
r.cfg.MTSRBSize = v
case "MTSRBElementSize":
v, err := strconv.Atoi(value)
if err != nil || v < 0 {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid MTSRBElementSize var", "value", value)
break
}
r.cfg.MTSRBElementSize = v
case "MTSRBWriteTimeout":
v, err := strconv.Atoi(value)
if err != nil || v <= 0 {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid MTSRBWriteTimeout var", "value", value)
break
}
r.cfg.MTSRBWriteTimeout = v
case "VBR":
v, ok := map[string]bool{"true": true, "false": false}[strings.ToLower(value)]
if !ok {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid VBR var", "value", value)
break
}
r.cfg.VBR = v
case "VBRQuality":
v, ok := map[string]config.Quality{"standard": config.QualityStandard, "fair": config.QualityFair, "good": config.QualityGood, "great": config.QualityGreat, "excellent": config.QualityExcellent}[strings.ToLower(value)]
if !ok {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid VBRQuality var", "value", value)
break
}
r.cfg.VBRQuality = v
case "VBRBitrate":
v, err := strconv.Atoi(value)
if err != nil || v <= 0 {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid VBRBitrate var", "value", value)
break
}
r.cfg.VBRBitrate = v
case "CameraChan":
v, err := strconv.Atoi(value)
if err != nil || (v != 1 && v != 2) {
r.cfg.Logger.Log(logger.Warning, pkg+"invalid CameraChan var", "value", value)
break
}
r.cfg.CameraChan = v
}
}
r.cfg.Logger.Log(logger.Info, pkg+"revid config changed", "config", fmt.Sprintf("%+v", r.cfg))
return nil
}
// processFrom is run as a routine to read from a input data source, lex and
// then send individual access units to revid's encoders.
func (r *Revid) processFrom(read io.Reader, delay time.Duration) {
r.err <- r.lexTo(r.encoders, read, delay)
r.cfg.Logger.Log(logger.Info, pkg+"finished lexing")
r.wg.Done()
}