lamemp3enc: GStreamer Good Plugins 1.0 Plugins Reference Manual

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).