transcode

Documentation

Index

• Variables
• type BitRate
• type CachingTranscoder
  • func NewCachingTranscoder(t Transcoder, cachePath string) *CachingTranscoder
  • func (t *CachingTranscoder) Transcode(ctx context.Context, profile Profile, in string, out io.Writer) error
• type FFmpegTranscoder
  • func NewFFmpegTranscoder() *FFmpegTranscoder
  • func (*FFmpegTranscoder) Transcode(ctx context.Context, profile Profile, in string, out io.Writer) error
• type NoneTranscoder
  • func NewNoneTranscoder() *NoneTranscoder
  • func (*NoneTranscoder) Transcode(_ context.Context, _ Profile, in string, out io.Writer) error
• type Profile
  • func NewProfile(mime string, suffix string, bitrate BitRate, exec string) Profile
  • func WithBitrate(p Profile, bitRate BitRate) Profile
  • func WithSeek(p Profile, seek time.Duration) Profile
  • func (p *Profile) BitRate() BitRate
  • func (p *Profile) MIME() string
  • func (p *Profile) Seek() time.Duration
  • func (p *Profile) Suffix() string
• type Transcoder

Variables

var (
	MP3    = NewProfile("audio/mpeg", "mp3", 128, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libmp3lame -f mp3 -`)
	MP3320 = NewProfile("audio/mpeg", "mp3", 320, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libmp3lame -f mp3 -`)
	MP3RG  = NewProfile("audio/mpeg", "mp3", 128, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libmp3lame -af "volume=replaygain=track:replaygain_preamp=6dB:replaygain_noclip=0, alimiter=level=disabled, asidedata=mode=delete:type=REPLAYGAIN" -metadata replaygain_album_gain= -metadata replaygain_album_peak= -metadata replaygain_track_gain= -metadata replaygain_track_peak= -metadata r128_album_gain= -metadata r128_track_gain= -f mp3 -`)

	Opus       = NewProfile("audio/ogg", "opus", 96, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libopus -vbr on -f opus -`)
	OpusRG     = NewProfile("audio/ogg", "opus", 96, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libopus -vbr on -af "volume=replaygain=track:replaygain_preamp=6dB:replaygain_noclip=0, alimiter=level=disabled, asidedata=mode=delete:type=REPLAYGAIN" -metadata replaygain_album_gain= -metadata replaygain_album_peak= -metadata replaygain_track_gain= -metadata replaygain_track_peak= -metadata r128_album_gain= -metadata r128_track_gain= -f opus -`)
	OpusRGLoud = NewProfile("audio/ogg", "opus", 96, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libopus -vbr on -af "aresample=96000:resampler=soxr, volume=replaygain=track:replaygain_preamp=15dB:replaygain_noclip=0, alimiter=level=disabled, asidedata=mode=delete:type=REPLAYGAIN" -metadata replaygain_album_gain= -metadata replaygain_album_peak= -metadata replaygain_track_gain= -metadata replaygain_track_peak= -metadata r128_album_gain= -metadata r128_track_gain= -f opus -`)

	Opus128       = NewProfile("audio/ogg", "opus", 128, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libopus -vbr on -f opus -`)
	Opus128RG     = NewProfile("audio/ogg", "opus", 128, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libopus -vbr on -af "volume=replaygain=track:replaygain_preamp=6dB:replaygain_noclip=0, alimiter=level=disabled, asidedata=mode=delete:type=REPLAYGAIN" -metadata replaygain_album_gain= -metadata replaygain_album_peak= -metadata replaygain_track_gain= -metadata replaygain_track_peak= -metadata r128_album_gain= -metadata r128_track_gain= -f opus -`)
	Opus128RGLoud = NewProfile("audio/ogg", "opus", 128, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libopus -vbr on -af "aresample=96000:resampler=soxr, volume=replaygain=track:replaygain_preamp=15dB:replaygain_noclip=0, alimiter=level=disabled, asidedata=mode=delete:type=REPLAYGAIN" -metadata replaygain_album_gain= -metadata replaygain_album_peak= -metadata replaygain_track_gain= -metadata replaygain_track_peak= -metadata r128_album_gain= -metadata r128_track_gain= -f opus -`)

	Opus192 = NewProfile("audio/ogg", "opus", 192, `ffmpeg -v 0 -i <file> -ss <seek> -map 0:a:0 -vn -b:a <bitrate> -c:a libopus -vbr on -f opus -`)

	PCM16le = NewProfile("audio/wav", "wav", 0, `ffmpeg -v 0 -i <file> -ss <seek> -c:a pcm_s16le -ac 2 -ar 48000 -f s16le -`)
)

Store as simple strings, since we may let the user provide their own profiles soon

var (
	ErrFFmpegKilled = fmt.Errorf("ffmpeg was killed early")
	ErrFFmpegExit   = fmt.Errorf("ffmpeg exited with non 0 status code")
)

var ErrNoProfileParts = fmt.Errorf("not enough profile parts")

var UserProfiles = map[string]Profile{
	"mp3":          MP3,
	"mp3_320":      MP3320,
	"mp3_rg":       MP3RG,
	"opus_car":     OpusRGLoud,
	"opus":         Opus,
	"opus_rg":      OpusRG,
	"opus_128_car": Opus128RGLoud,
	"opus_128":     Opus128,
	"opus_128_rg":  Opus128RG,
	"opus_192":     Opus192,
}

Types

type BitRate

type BitRate uint // kilobits/s

type CachingTranscoder

type CachingTranscoder struct {
	// contains filtered or unexported fields
}

func NewCachingTranscoder

func NewCachingTranscoder(t Transcoder, cachePath string) *CachingTranscoder

func (*CachingTranscoder) Transcode

func (t *CachingTranscoder) Transcode(ctx context.Context, profile Profile, in string, out io.Writer) error

type FFmpegTranscoder

type FFmpegTranscoder struct{}

func NewFFmpegTranscoder

func NewFFmpegTranscoder() *FFmpegTranscoder

func (*FFmpegTranscoder) Transcode

func (*FFmpegTranscoder) Transcode(ctx context.Context, profile Profile, in string, out io.Writer) error

type NoneTranscoder

type NoneTranscoder struct{}

func NewNoneTranscoder

func NewNoneTranscoder() *NoneTranscoder

func (*NoneTranscoder) Transcode

func (*NoneTranscoder) Transcode(_ context.Context, _ Profile, in string, out io.Writer) error

type Profile

type Profile struct {
	// contains filtered or unexported fields
}

func NewProfile

func NewProfile(mime string, suffix string, bitrate BitRate, exec string) Profile

func WithBitrate

func WithBitrate(p Profile, bitRate BitRate) Profile

func WithSeek

func WithSeek(p Profile, seek time.Duration) Profile

func (*Profile) BitRate

func (p *Profile) BitRate() BitRate

func (*Profile) MIME

func (p *Profile) MIME() string

func (*Profile) Seek

func (p *Profile) Seek() time.Duration

func (*Profile) Suffix

func (p *Profile) Suffix() string

type Transcoder

type Transcoder interface {
	Transcode(ctx context.Context, profile Profile, in string, out io.Writer) error
}