706 lines
15 KiB
Go
706 lines
15 KiB
Go
package go_vod
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import (
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"bufio"
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"fmt"
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"io"
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"log"
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"net/http"
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"os"
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"os/exec"
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"strconv"
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"strings"
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"sync"
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"syscall"
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"time"
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)
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const (
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ENCODER_COPY = "copy"
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ENCODER_X264 = "libx264"
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ENCODER_VAAPI = "h264_vaapi"
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ENCODER_NVENC = "h264_nvenc"
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QUALITY_MAX = "max"
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CODEC_H264 = "h264"
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)
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type Stream struct {
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c *Config
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m *Manager
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quality string
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order int
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height int
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width int
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bitrate int
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goal int
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mutex sync.Mutex
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chunks map[int]*Chunk
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seenChunks map[int]bool // only for stdout reader
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coder *exec.Cmd
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inactive int
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stop chan bool
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}
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func (s *Stream) Run() {
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// run every 5s
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t := time.NewTicker(5 * time.Second)
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defer t.Stop()
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s.stop = make(chan bool)
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for {
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select {
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case <-t.C:
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s.mutex.Lock()
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// Prune chunks
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for id := range s.chunks {
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if id < s.goal-s.c.GoalBufferMax {
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s.pruneChunk(id)
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}
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}
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s.inactive++
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// Nothing done for 2 minutes
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if s.inactive >= s.c.StreamIdleTime/5 && s.coder != nil {
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t.Stop()
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s.clear()
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}
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s.mutex.Unlock()
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case <-s.stop:
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t.Stop()
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s.mutex.Lock()
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s.clear()
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s.mutex.Unlock()
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return
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}
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}
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}
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func (s *Stream) clear() {
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log.Printf("%s-%s: stopping stream", s.m.id, s.quality)
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for _, chunk := range s.chunks {
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// Delete files
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s.pruneChunk(chunk.id)
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}
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s.chunks = make(map[int]*Chunk)
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s.seenChunks = make(map[int]bool)
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s.goal = 0
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if s.coder != nil {
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s.coder.Process.Kill()
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s.coder.Wait()
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s.coder = nil
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}
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}
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func (s *Stream) Stop() {
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select {
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case s.stop <- true:
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default:
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}
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}
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func (s *Stream) ServeList(w http.ResponseWriter, r *http.Request) error {
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WriteM3U8ContentType(w)
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w.Write([]byte("#EXTM3U\n"))
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w.Write([]byte("#EXT-X-VERSION:4\n"))
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w.Write([]byte("#EXT-X-MEDIA-SEQUENCE:0\n"))
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w.Write([]byte("#EXT-X-PLAYLIST-TYPE:VOD\n"))
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w.Write([]byte(fmt.Sprintf("#EXT-X-TARGETDURATION:%d\n", s.c.ChunkSize)))
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query := GetQueryString(r)
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duration := s.m.probe.Duration.Seconds()
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i := 0
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for duration > 0 {
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size := float64(s.c.ChunkSize)
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if duration < size {
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size = duration
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}
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w.Write([]byte(fmt.Sprintf("#EXTINF:%.3f, nodesc\n", size)))
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w.Write([]byte(fmt.Sprintf("%s-%06d.ts%s\n", s.quality, i, query)))
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duration -= float64(s.c.ChunkSize)
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i++
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}
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w.Write([]byte("#EXT-X-ENDLIST\n"))
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return nil
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}
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func (s *Stream) ServeChunk(w http.ResponseWriter, id int) error {
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s.mutex.Lock()
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defer s.mutex.Unlock()
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s.inactive = 0
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s.checkGoal(id)
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// Already have this chunk
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if chunk, ok := s.chunks[id]; ok {
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// Chunk is finished, just return it
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if chunk.done {
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s.returnChunk(w, chunk)
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return nil
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}
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// Still waiting on transcoder
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s.waitForChunk(w, chunk)
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return nil
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}
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// Will have this soon enough
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foundBehind := false
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for i := id - 1; i > id-s.c.LookBehind && i >= 0; i-- {
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if _, ok := s.chunks[i]; ok {
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foundBehind = true
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}
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}
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if foundBehind {
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// Make sure the chunk exists
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chunk := s.createChunk(id)
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// Wait for it
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s.waitForChunk(w, chunk)
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return nil
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}
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// Let's start over
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s.restartAtChunk(w, id)
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return nil
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}
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func (s *Stream) ServeFullVideo(w http.ResponseWriter, r *http.Request) error {
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args := s.transcodeArgs(0, false)
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if s.m.probe.CodecName == CODEC_H264 && s.quality == QUALITY_MAX {
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// try to just send the original file
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http.ServeFile(w, r, s.m.path)
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return nil
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}
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// Output mov
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args = append(args, []string{
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"-movflags", "frag_keyframe+empty_moov+faststart",
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"-f", "mp4", "pipe:1",
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}...)
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coder := exec.Command(s.c.FFmpeg, args...)
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log.Printf("%s-%s: %s", s.m.id, s.quality, strings.Join(coder.Args[:], " "))
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cmdStdOut, err := coder.StdoutPipe()
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if err != nil {
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log.Printf("FATAL: ffmpeg command stdout failed with %s\n", err)
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}
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cmdStdErr, err := coder.StderrPipe()
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if err != nil {
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log.Printf("FATAL: ffmpeg command stdout failed with %s\n", err)
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}
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err = coder.Start()
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if err != nil {
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log.Printf("FATAL: ffmpeg command failed with %s\n", err)
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}
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go s.monitorStderr(cmdStdErr)
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// Write to response
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defer cmdStdOut.Close()
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stdoutReader := bufio.NewReader(cmdStdOut)
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// Write mov headers
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w.Header().Set("Content-Type", "video/mp4")
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w.WriteHeader(http.StatusOK)
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flusher, ok := w.(http.Flusher)
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if !ok {
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http.Error(w, "Server does not support Flusher!",
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http.StatusInternalServerError)
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return nil
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}
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// Write data, flusing every 1MB
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buf := make([]byte, 1024*1024)
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for {
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n, err := stdoutReader.Read(buf)
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if err != nil {
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if err == io.EOF {
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break
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}
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log.Printf("FATAL: ffmpeg command failed with %s\n", err)
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break
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}
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_, err = w.Write(buf[:n])
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if err != nil {
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log.Printf("%s-%s: client closed connection", s.m.id, s.quality)
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log.Println(err)
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break
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}
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flusher.Flush()
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}
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// Terminate ffmpeg process
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coder.Process.Kill()
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coder.Wait()
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return nil
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}
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func (s *Stream) createChunk(id int) *Chunk {
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if c, ok := s.chunks[id]; ok {
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return c
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} else {
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s.chunks[id] = NewChunk(id)
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return s.chunks[id]
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}
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}
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func (s *Stream) pruneChunk(id int) {
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delete(s.chunks, id)
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// Remove file
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filename := s.getTsPath(id)
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os.Remove(filename)
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}
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func (s *Stream) returnChunk(w http.ResponseWriter, chunk *Chunk) {
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// This function is called with lock, but we don't need it
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s.mutex.Unlock()
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defer s.mutex.Lock()
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// Read file and write to response
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filename := s.getTsPath(chunk.id)
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f, err := os.Open(filename)
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if err != nil {
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log.Println(err)
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w.WriteHeader(http.StatusInternalServerError)
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return
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}
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defer f.Close()
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w.Header().Set("Content-Type", "video/MP2T")
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io.Copy(w, f)
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}
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func (s *Stream) waitForChunk(w http.ResponseWriter, chunk *Chunk) {
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if chunk.done {
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s.returnChunk(w, chunk)
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return
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}
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// Add our channel
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notif := make(chan bool)
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chunk.notifs = append(chunk.notifs, notif)
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t := time.NewTimer(10 * time.Second)
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coder := s.coder
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s.mutex.Unlock()
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select {
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case <-notif:
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t.Stop()
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case <-t.C:
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}
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s.mutex.Lock()
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// remove channel
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for i, c := range chunk.notifs {
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if c == notif {
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chunk.notifs = append(chunk.notifs[:i], chunk.notifs[i+1:]...)
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break
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}
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}
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// check for success
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if chunk.done {
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s.returnChunk(w, chunk)
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return
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}
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// Check if coder was changed
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if coder != s.coder {
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w.WriteHeader(http.StatusConflict)
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return
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}
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// Return timeout error
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w.WriteHeader(http.StatusRequestTimeout)
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}
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func (s *Stream) restartAtChunk(w http.ResponseWriter, id int) {
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// Stop current transcoder
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s.clear()
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chunk := s.createChunk(id) // create first chunk
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// Start the transcoder
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s.goal = id + s.c.GoalBufferMax
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s.transcode(id)
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s.waitForChunk(w, chunk) // this is also a request
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}
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// Get arguments to ffmpeg
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func (s *Stream) transcodeArgs(startAt float64, isHls bool) []string {
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args := []string{
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"-loglevel", "warning",
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}
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if startAt > 0 {
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args = append(args, []string{
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"-ss", fmt.Sprintf("%.6f", startAt),
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}...)
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}
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// encoder selection
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CV := ENCODER_X264
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// Check whether hwaccel should be used
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if s.c.VAAPI {
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CV = ENCODER_VAAPI
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extra := "-hwaccel vaapi -hwaccel_device /dev/dri/renderD128 -hwaccel_output_format vaapi"
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args = append(args, strings.Split(extra, " ")...)
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} else if s.c.NVENC {
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CV = ENCODER_NVENC
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extra := "-hwaccel cuda"
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args = append(args, strings.Split(extra, " ")...)
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}
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// Disable autorotation (see transpose comments below)
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if s.c.UseTranspose {
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args = append(args, []string{"-noautorotate"}...)
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}
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// Input specs
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args = append(args, []string{
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"-i", s.m.path, // Input file
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"-copyts", // So the "-to" refers to the original TS
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"-fflags", "+genpts",
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}...)
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// Filters
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format := "format=nv12"
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scaler := "scale"
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scalerArgs := make([]string, 0)
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scalerArgs = append(scalerArgs, "force_original_aspect_ratio=decrease")
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if CV == ENCODER_VAAPI {
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format = "format=nv12|vaapi,hwupload"
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scaler = "scale_vaapi"
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scalerArgs = append(scalerArgs, "format=nv12")
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} else if CV == ENCODER_NVENC {
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format = "format=nv12|cuda,hwupload"
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scaler = fmt.Sprintf("scale_%s", s.c.NVENCScale)
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// workaround to force scale_cuda to examine all input frames
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if s.c.NVENCScale == "cuda" {
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scalerArgs = append(scalerArgs, "passthrough=0")
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}
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}
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// Scale height and width if not max quality
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if s.quality != QUALITY_MAX {
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maxDim := s.height
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if s.width > s.height {
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maxDim = s.width
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}
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scalerArgs = append(scalerArgs, fmt.Sprintf("w=%d", maxDim))
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scalerArgs = append(scalerArgs, fmt.Sprintf("h=%d", maxDim))
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}
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// Apply filter
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if CV != ENCODER_COPY {
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filter := fmt.Sprintf("%s,%s=%s", format, scaler, strings.Join(scalerArgs, ":"))
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// Rotation is a mess: https://trac.ffmpeg.org/ticket/8329
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// 1/ -noautorotate copies the sidecar metadata to the output
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// 2/ autorotation doesn't seem to work with some types of HW (at least not with VAAPI)
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// 3/ autorotation doesn't work with HLS streams
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// 4/ VAAPI cannot transport on AMD GPUs
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// So: give the user to disable autorotation for HLS and use a manual transpose
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if isHls && s.c.UseTranspose {
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transposer := "transpose"
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if CV == ENCODER_VAAPI {
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transposer = "transpose_vaapi"
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} else if CV == ENCODER_NVENC {
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transposer = fmt.Sprintf("transpose_%s", s.c.NVENCScale)
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}
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if transposer != "transpose_cuda" { // does not exist
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if s.m.probe.Rotation == -90 {
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filter = fmt.Sprintf("%s,%s=1", filter, transposer)
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} else if s.m.probe.Rotation == 90 {
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filter = fmt.Sprintf("%s,%s=2", filter, transposer)
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} else if s.m.probe.Rotation == 180 || s.m.probe.Rotation == -180 {
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filter = fmt.Sprintf("%s,%s=1,%s=1", filter, transposer, transposer)
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}
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}
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}
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args = append(args, []string{"-vf", filter}...)
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args = append(args, []string{"-profile:v", "main"}...)
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}
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// Output specs for video
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args = append(args, []string{
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"-map", "0:v:0",
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"-c:v", CV,
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}...)
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// Device specific output args
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if CV == ENCODER_VAAPI {
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args = append(args, []string{"-global_quality", fmt.Sprintf("%d", s.c.QF)}...)
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if s.c.VAAPILowPower {
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args = append(args, []string{"-low_power", "1"}...)
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}
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} else if CV == ENCODER_NVENC {
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args = append(args, []string{
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"-preset", "p6",
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"-tune", "ll",
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"-rc", "vbr",
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"-rc-lookahead", "30",
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"-cq", fmt.Sprintf("%d", s.c.QF),
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}...)
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if s.c.NVENCTemporalAQ {
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args = append(args, []string{"-temporal-aq", "1"}...)
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}
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} else if CV == ENCODER_X264 {
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args = append(args, []string{
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"-preset", "faster",
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"-crf", fmt.Sprintf("%d", s.c.QF),
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}...)
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}
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// Audio output specs
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args = append(args, []string{
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"-map", "0:a:0?",
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"-c:a", "aac",
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"-ac", "1",
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}...)
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return args
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}
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func (s *Stream) transcode(startId int) {
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if startId > 0 {
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// Start one frame before
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// This ensures that the keyframes are aligned
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startId--
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}
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startAt := float64(startId * s.c.ChunkSize)
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args := s.transcodeArgs(startAt, true)
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// Segmenting specs
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args = append(args, []string{
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"-start_number", fmt.Sprintf("%d", startId),
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"-avoid_negative_ts", "disabled",
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"-f", "hls",
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"-hls_flags", "split_by_time",
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"-hls_time", fmt.Sprintf("%d", s.c.ChunkSize),
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"-hls_segment_type", "mpegts",
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"-hls_segment_filename", s.getTsPath(-1),
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}...)
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// Keyframe specs
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if s.c.UseGopSize && s.m.probe.FrameRate > 0 {
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// Fix GOP size
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args = append(args, []string{
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"-g", fmt.Sprintf("%d", s.c.ChunkSize*s.m.probe.FrameRate),
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"-keyint_min", fmt.Sprintf("%d", s.c.ChunkSize*s.m.probe.FrameRate),
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}...)
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} else {
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// Force keyframes every chunk
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args = append(args, []string{
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"-force_key_frames", fmt.Sprintf("expr:gte(t,n_forced*%d)", s.c.ChunkSize),
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}...)
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}
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// Output to stdout
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args = append(args, "-")
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// Start the process
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s.coder = exec.Command(s.c.FFmpeg, args...)
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// Log command, quoting the args as needed
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quotedArgs := make([]string, len(s.coder.Args))
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invalidChars := strings.Join([]string{" ", "=", ":", "\"", "\\", "\n", "\t"}, "")
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for i, arg := range s.coder.Args {
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if strings.ContainsAny(arg, invalidChars) {
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quotedArgs[i] = fmt.Sprintf("\"%s\"", arg)
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} else {
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quotedArgs[i] = arg
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}
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}
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log.Printf("%s-%s: %s", s.m.id, s.quality, strings.Join(quotedArgs[:], " "))
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cmdStdOut, err := s.coder.StdoutPipe()
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if err != nil {
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log.Printf("FATAL: ffmpeg command stdout failed with %s\n", err)
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}
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|
|
cmdStdErr, err := s.coder.StderrPipe()
|
|
if err != nil {
|
|
log.Printf("FATAL: ffmpeg command stdout failed with %s\n", err)
|
|
}
|
|
|
|
err = s.coder.Start()
|
|
if err != nil {
|
|
log.Printf("FATAL: ffmpeg command failed with %s\n", err)
|
|
}
|
|
|
|
go s.monitorTranscodeOutput(cmdStdOut, startAt)
|
|
go s.monitorStderr(cmdStdErr)
|
|
go s.monitorExit()
|
|
}
|
|
|
|
func (s *Stream) checkGoal(id int) {
|
|
goal := id + s.c.GoalBufferMin
|
|
if goal > s.goal {
|
|
s.goal = id + s.c.GoalBufferMax
|
|
|
|
// resume encoding
|
|
if s.coder != nil {
|
|
log.Printf("%s-%s: resuming transcoding", s.m.id, s.quality)
|
|
s.coder.Process.Signal(syscall.SIGCONT)
|
|
}
|
|
}
|
|
}
|
|
|
|
func (s *Stream) getTsPath(id int) string {
|
|
if id == -1 {
|
|
return fmt.Sprintf("%s/%s-%%06d.ts", s.m.tempDir, s.quality)
|
|
}
|
|
return fmt.Sprintf("%s/%s-%06d.ts", s.m.tempDir, s.quality, id)
|
|
}
|
|
|
|
// Separate goroutine
|
|
func (s *Stream) monitorTranscodeOutput(cmdStdOut io.ReadCloser, startAt float64) {
|
|
s.mutex.Lock()
|
|
coder := s.coder
|
|
s.mutex.Unlock()
|
|
|
|
defer cmdStdOut.Close()
|
|
stdoutReader := bufio.NewReader(cmdStdOut)
|
|
|
|
for {
|
|
if s.coder != coder {
|
|
break
|
|
}
|
|
|
|
line, err := stdoutReader.ReadBytes('\n')
|
|
if err == io.EOF {
|
|
if len(line) == 0 {
|
|
break
|
|
}
|
|
} else if err != nil {
|
|
log.Println(err)
|
|
break
|
|
} else {
|
|
line = line[:(len(line) - 1)]
|
|
}
|
|
|
|
l := string(line)
|
|
|
|
if strings.Contains(l, ".ts") {
|
|
// 1080p-000003.ts
|
|
idx := strings.Split(strings.Split(l, "-")[1], ".")[0]
|
|
id, err := strconv.Atoi(idx)
|
|
if err != nil {
|
|
log.Println("Error parsing chunk id")
|
|
}
|
|
|
|
if s.seenChunks[id] {
|
|
continue
|
|
}
|
|
s.seenChunks[id] = true
|
|
|
|
// Debug
|
|
log.Printf("%s-%s: recv %s", s.m.id, s.quality, l)
|
|
|
|
func() {
|
|
s.mutex.Lock()
|
|
defer s.mutex.Unlock()
|
|
|
|
// The coder has changed; do nothing
|
|
if s.coder != coder {
|
|
return
|
|
}
|
|
|
|
// Notify everyone
|
|
chunk := s.createChunk(id)
|
|
if chunk.done {
|
|
return
|
|
}
|
|
chunk.done = true
|
|
for _, n := range chunk.notifs {
|
|
n <- true
|
|
}
|
|
|
|
// Check goal satisfied
|
|
if id >= s.goal {
|
|
log.Printf("%s-%s: goal satisfied: %d", s.m.id, s.quality, s.goal)
|
|
s.coder.Process.Signal(syscall.SIGSTOP)
|
|
}
|
|
}()
|
|
}
|
|
}
|
|
}
|
|
|
|
func (s *Stream) monitorStderr(cmdStdErr io.ReadCloser) {
|
|
stderrReader := bufio.NewReader(cmdStdErr)
|
|
|
|
for {
|
|
line, err := stderrReader.ReadBytes('\n')
|
|
if err == io.EOF {
|
|
if len(line) == 0 {
|
|
break
|
|
}
|
|
} else if err != nil {
|
|
log.Println(err)
|
|
break
|
|
} else {
|
|
line = line[:(len(line) - 1)]
|
|
}
|
|
log.Println("ffmpeg-error:", string(line))
|
|
}
|
|
}
|
|
|
|
func (s *Stream) monitorExit() {
|
|
// Join the process
|
|
coder := s.coder
|
|
err := coder.Wait()
|
|
|
|
// Try to get exit status
|
|
if exitError, ok := err.(*exec.ExitError); ok {
|
|
exitcode := exitError.ExitCode()
|
|
log.Printf("%s-%s: ffmpeg exited with status: %d", s.m.id, s.quality, exitcode)
|
|
|
|
s.mutex.Lock()
|
|
defer s.mutex.Unlock()
|
|
|
|
// If error code is >0, there was an error in transcoding
|
|
if exitcode > 0 && s.coder == coder {
|
|
// Notify all outstanding chunks
|
|
for _, chunk := range s.chunks {
|
|
for _, n := range chunk.notifs {
|
|
n <- true
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|