lamemp3enc

lamemp3enc

Properties

gint bitrate Read / Write / Construct
gboolean cbr Read / Write / Construct
GstLameMP3EncEncodingEngineQuality encoding-engine-quality Read / Write / Construct
gboolean mono Read / Write / Construct
gfloat quality Read / Write / Construct
GstLameMP3EncTarget target Read / Write / Construct

Types and Values

struct GstLameMP3Enc

Object Hierarchy

    GObject
    ╰── GInitiallyUnowned
        ╰── GstObject
            ╰── GstElement
                ╰── GstAudioEncoder
                    ╰── GstLameMP3Enc

Implemented Interfaces

GstLameMP3Enc implements GstPreset.

Description

This element encodes raw integer audio into an MPEG-1 layer 3 (MP3) stream. Note that MP3 is not a free format, there are licensing and patent issues to take into consideration. See Ogg/Vorbis for a royalty free (and often higher quality) alternative.

Output sample rate

If no fixed output sample rate is negotiated on the element's src pad, the element will choose an optimal sample rate to resample to internally. For example, a 16-bit 44.1 KHz mono audio stream encoded at 48 kbit will get resampled to 32 KHz. Use filter caps on the src pad to force a particular sample rate.

Example pipelines

1
gst-launch-1.0 -v audiotestsrc wave=sine num-buffers=100 ! audioconvert ! lamemp3enc ! filesink location=sine.mp3
Encode a test sine signal to MP3.
1
gst-launch-1.0 -v autoaudiosrc ! audioconvert ! lamemp3enc target=bitrate bitrate=192 ! filesink location=alsasrc.mp3
Record from a sound card using ALSA and encode to MP3 with an average bitrate of 192kbps
1
gst-launch-1.0 -v filesrc location=music.wav ! decodebin ! audioconvert ! audioresample ! lamemp3enc target=quality quality=0 ! id3v2mux ! filesink location=music.mp3
Transcode from a .wav file to MP3 (the id3v2mux element is optional) with best VBR quality
1
gst-launch-1.0 -v cdda://5 ! audioconvert ! lamemp3enc target=bitrate cbr=true bitrate=192 ! filesink location=track5.mp3
Encode Audio CD track 5 to MP3 with a constant bitrate of 192kbps
1
gst-launch-1.0 -v audiotestsrc num-buffers=10 ! audio/x-raw,rate=44100,channels=1 ! lamemp3enc target=bitrate cbr=true bitrate=48 ! filesink location=test.mp3
Encode to a fixed sample rate

Synopsis

Element Information

plugin

lame

author

Sebastian Dröge <sebastian.droege@collabora.co.uk>

class

Codec/Encoder/Audio

Element Pads

name

sink

direction

sink

presence

always

details

audio/x-raw, format=(string)S16LE, layout=(string)interleaved, rate=(int){ 8000, 11025, 12000, 16000, 22050, 24000, 32000, 44100, 48000 }, channels=(int)1

audio/x-raw, format=(string)S16LE, layout=(string)interleaved, rate=(int){ 8000, 11025, 12000, 16000, 22050, 24000, 32000, 44100, 48000 }, channels=(int)2, channel-mask=(bitmask)0x0000000000000003

name

src

direction

source

presence

always

details

audio/mpeg, mpegversion=(int)1, layer=(int)3, rate=(int){ 8000, 11025, 12000, 16000, 22050, 24000, 32000, 44100, 48000 }, channels=(int)[ 1, 2 ]

Functions

Types and Values

struct GstLameMP3Enc

struct GstLameMP3Enc;

Opaque data structure.

Property Details

The “bitrate” property

  “bitrate”                  gint

Bitrate in kbit/sec (Only valid if target is bitrate, for CBR one of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 or 320).

Flags: Read / Write / Construct

Allowed values: [8,320]

Default value: 128


The “cbr” property

  “cbr”                      gboolean

Enforce constant bitrate encoding (Only valid if target is bitrate).

Flags: Read / Write / Construct

Default value: FALSE


The “encoding-engine-quality” property

  “encoding-engine-quality”  GstLameMP3EncEncodingEngineQuality

Quality/speed of the encoding engine, this does not affect the bitrate!.

Flags: Read / Write / Construct

Default value: Standard


The “mono” property

  “mono”                     gboolean

Enforce mono encoding.

Flags: Read / Write / Construct

Default value: FALSE


The “quality” property

  “quality”                  gfloat

VBR Quality from 0 to 10, 0 being the best (Only valid if target is quality).

Flags: Read / Write / Construct

Allowed values: [0,9.999]

Default value: 4


The “target” property

  “target”                   GstLameMP3EncTarget

Optimize for quality or bitrate.

Flags: Read / Write / Construct

Default value: Quality

See Also

lame, mad, vorbisenc