init

ffmpeg/ffmpeg.go

@@ -0,0 +1,120 @@
+package ffmpeg
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"os/exec"
+	"path"
+	"strconv"
+	"stream-poc2/model"
+)
+
+// EncodeChunk doesn't have the nicest function signature...
+func EncodeChunk(profileSettings model.VideoProfileSettings, nativeHeight int, preset string, origSegmentPath string, writer io.Writer) error {
+	ffmpegArgs := []string{
+		"-nostdin", "-hide_banner", "-loglevel", "error",
+	}
+
+	if profileSettings.Resolution.Height != nativeHeight {
+		// apply resize filter
+		ffmpegArgs = append(ffmpegArgs,
+			"-hwaccel", "cuda", "-hwaccel_output_format", "cuda",
+			"-i", origSegmentPath,
+			"-vf", fmt.Sprintf("scale_cuda=%d:%d", profileSettings.Resolution.Width, profileSettings.Resolution.Height),
+		)
+	} else {
+		// just load the segment
+		ffmpegArgs = append(ffmpegArgs,
+			"-i", origSegmentPath,
+		)
+	}
+
+	ffmpegArgs = append(ffmpegArgs,
+		"-copyts",
+		"-c:v", profileSettings.FFMpegCodec(),
+	)
+	if preset != "" {
+		ffmpegArgs = append(ffmpegArgs,
+			"-preset", preset,
+		)
+	}
+
+	ffmpegArgs = append(ffmpegArgs,
+		"-b:v", strconv.Itoa(profileSettings.AvgBitrate), "-maxrate", strconv.Itoa(profileSettings.MaxBitrate), "-bufsize", "1M",
+		"-an", // <- no audio
+		"-f", "mpegts", "-mpegts_copyts", "1",
+		"-",
+	)
+
+	log.Println("exec ffmpeg args: ", ffmpegArgs)
+
+	cmd := exec.Command("/usr/bin/ffmpeg", ffmpegArgs...)
+	cmd.Stdout = writer
+	cmd.Stderr = os.Stderr
+
+	err := cmd.Run()
+	if err != nil {
+		log.Println("Failed to run:", err)
+		return err
+	}
+
+	return nil
+}
+
+// MakeSegments has the ugliest function signature no the planet
+func MakeSegments(filepath, outdir string, audioStreams []model.AudioStream) (string, []string, error) {
+	segmentsVideoCSV := path.Join(outdir, "segments_video.csv")
+	segmentsAudioCSV := make([]string, len(audioStreams))
+
+	// do slicing
+	ffmpegArgs := []string{
+		"-nostdin", "-hide_banner", "-loglevel", "error",
+		"-i", filepath,
+		// video stream
+		"-c:v", "copy", "-an",
+		"-f", "ssegment", "-segment_format", "mpegts", "-segment_list", segmentsVideoCSV,
+		"-segment_list_type", "csv", "-segment_time", strconv.Itoa(SlicerTargetDurationSec), path.Join(outdir, "video", "s%d.ts"),
+	}
+
+	for i, audioStream := range audioStreams {
+		csvName := path.Join(outdir, fmt.Sprintf("segments_audio_%d.csv", audioStream.Index))
+		segmentsAudioCSV[i] = csvName
+
+		ffmpegArgs = append(ffmpegArgs,
+			// audio streams (encode to mp3)
+			"-vn", "-map", fmt.Sprintf("0:a:%d", i),
+		)
+
+		if audioStream.Codec != "mp3" {
+			// mp3 always works
+			// TODO: This does not update the stream info in the metadata !!!
+			log.Println("Transcoding audio to mp3 for stream ", audioStream.Index)
+			ffmpegArgs = append(ffmpegArgs,
+				"-c:a", "libmp3lame", "-q:a", "0",
+			)
+		} else {
+			log.Println("Not transcoding audio as it is already mp3 for stream ", audioStream.Index)
+			ffmpegArgs = append(ffmpegArgs,
+				"-c:a", "copy",
+			)
+		}
+
+		ffmpegArgs = append(ffmpegArgs,
+			"-f", "ssegment", "-segment_format", "mpegts", "-segment_list", csvName,
+			"-segment_list_type", "csv", "-segment_time", strconv.Itoa(SlicerTargetDurationSec), path.Join(outdir, "audio", strconv.Itoa(audioStream.Index), "s%d.ts"),
+		)
+	}
+
+	cmd := exec.Command("/usr/bin/ffmpeg", ffmpegArgs...)
+	cmd.Stderr = os.Stderr
+
+	err := cmd.Run()
+	if err != nil {
+		log.Println("failed to segment:", err)
+		return "", nil, err
+	}
+
+	return segmentsVideoCSV, segmentsAudioCSV, nil
+}