Files
go2tv/soapcalls/utils/transcode.go
2024-12-27 16:47:08 +02:00

73 lines
1.4 KiB
Go

//go:build !windows
// +build !windows
package utils
import (
"errors"
"fmt"
"io"
"os/exec"
"strconv"
)
var (
ErrInvalidInput = errors.New("invalid ffmpeg input")
)
// ServeTranscodedStream passes an input file or io.Reader to ffmpeg and writes the output directly
// to our io.Writer.
func ServeTranscodedStream(w io.Writer, input interface{}, ff *exec.Cmd, ffmpegPath, subs string, seekSeconds int) error {
// Pipe streaming is not great as explained here
// https://video.stackexchange.com/questions/34087/ffmpeg-fails-on-pipe-to-pipe-video-decoding.
// That's why if we have the option to pass the file directly to ffmpeg, we should.
var in string
switch f := input.(type) {
case string:
in = f
case io.Reader:
in = "pipe:0"
default:
return ErrInvalidInput
}
if ff != nil && ff.Process != nil {
_ = ff.Process.Kill()
}
vf := "format=yuv420p"
charenc, err := getCharDet(subs)
if err == nil {
vf = fmt.Sprintf("subtitles='%s':charenc=%s,format=yuv420p", subs, charenc)
if charenc == "UTF-8" {
vf = fmt.Sprintf("subtitles='%s',format=yuv420p", subs)
}
}
cmd := exec.Command(
ffmpegPath,
"-re",
"-ss", strconv.Itoa(seekSeconds),
"-copyts",
"-i", in,
"-vcodec", "h264",
"-acodec", "aac",
"-ac", "2",
"-vf", vf,
"-preset", "ultrafast",
"-movflags", "+faststart",
"-f", "mpegts",
"pipe:1",
)
*ff = *cmd
if in == "pipe:0" {
ff.Stdin = input.(io.Reader)
}
ff.Stdout = w
return ff.Run()
}