Converting raw audio to ogg with gstreamer - audio

Question

The following pipeline results in a 3kb .ogg file (I assume it's just an empty container):
gst-launch-1.0 --gst-debug=3 filesrc location=test.raw
! 'audio/x-raw, format=S16LE, channels=1, rate=32000'
! audioconvert
! vorbisenc
! oggmux
! filesink location=test.ogg
Here's the debug output:
Setting pipeline to PAUSED ...
Pipeline is PREROLLING ...
Redistribute latency...
0:00:00.048490941 813 0x556bf3625000 FIXME basesink gstbasesink.c:3077:gst_base_sink_default_event:<filesink0> stream-start event without group-id. Consider implementing group-id handling in the upstream elements
0:00:00.048541997 813 0x556bf3625000 WARN audioencoder gstaudioencoder.c:985:gst_audio_encoder_finish_frame:<vorbisenc0> Can't copy metadata because input buffer disappeared
Pipeline is PREROLLED ...
Setting pipeline to PLAYING ...
New clock: GstSystemClock
0:00:00.139954729 813 0x556bf3625000 WARN basesrc gstbasesrc.c:2400:gst_base_src_update_length:<filesrc0> processing at or past EOS
Got EOS from element "pipeline0".
Execution ended after 0:00:00.091883401
Setting pipeline to PAUSED ...
Setting pipeline to READY ...
Setting pipeline to NULL ...
Freeing pipeline ...
When I add this wav encode/decode, I get a good .ogg file:
gst-launch-1.0 --gst-debug=3 filesrc location=test.raw
! 'audio/x-raw, format=S16LE, channels=1, rate=32000'
! audioconvert
! wavenc
! wavparse
! audioconvert
! vorbisenc
! oggmux
! filesink location=test.ogg
debug output:
Setting pipeline to PAUSED ...
Pipeline is PREROLLING ...
Redistribute latency...
0:00:00.135676651 822 0x562b3cd64770 FIXME basesink gstbasesink.c:3077:gst_base_sink_default_event:<filesink0> stream-start event without group-id. Consider implementing group-id handling in the upstream elements
0:00:00.135718946 822 0x562b3cd64770 WARN audioencoder gstaudioencoder.c:985:gst_audio_encoder_finish_frame:<vorbisenc0> Can't copy metadata because input buffer disappeared
Pipeline is PREROLLED ...
Setting pipeline to PLAYING ...
New clock: GstSystemClock
0:00:00.219188746 822 0x562b3cd64770 WARN wavenc gstwavenc.c:795:gst_wavenc_write_toc:<wavenc0> have no toc
Got EOS from element "pipeline0".
Execution ended after 0:00:00.083921991
Setting pipeline to PAUSED ...
Setting pipeline to READY ...
Setting pipeline to NULL ...
Freeing pipeline ...
So my question is: what is the second pipeline, with wavenc ! wavparse, providing that the first is missing and is there a more straight-forward way to specify it or is the 2nd form actually the 'right' way to do it?

Answer 1

The first pipeline is fine as it works with the testaudiosrc (audio/x-raw-int)
I'm assuming your uncompressed audio file must be an uncompressed WAV file.
https://en.wikipedia.org/wiki/List_of_codecs#Audio_compression_formats
Wavenc may be preprocessing the LPCM and converting to something vorbisenc can use. I suspect the data width needs to be 32 or 64 for vorbisenc and that may be the showstopper.
PCM signed 16-bit little-endian (S16LE) >
audioconvert - Convert audio to different formats (in:audio/x-raw-int out:audio/x-raw-int)
wavenc - Encode raw audio into WAV (in:audio/x-raw-int out:audio/x-wav)
wavparse - Parse a .wav file into raw audio (in:audio/x-wav out:audio/x-raw-float width: { 32, 64 })
vorbisenc - Encodes audio in Vorbis format (in:audio/x-raw-float out:audio/x-vorbis)
gst-launch audiotestsrc num-buffers=50 \
! vorbisenc \
! oggmux \
! filesink location=test.ogg
play test.ogg
addendum: I downloaded your file and was able to confirm you were doing unrealized stream conversion from 16 to 32 bit. Vorbisenc only accepts a 32 bit width. To answer your original question, no, you do not need the wavparsing. Here is the efficient pipeline you were looking for, simplified for width conversion.
gst-launch --gst-debug=2 filesrc location=test.raw \
! audio/x-raw-int, width=16, channels=2, depth=16, rate=16000, endianness=1234, signed=true \
! audioconvert \
! audio/x-raw-float, width=32, channels=2, rate=16000, endianness=1234, signed=true \
! vorbisenc \
! oggmux \
! filesink location=test.ogg