correct way to decode AAC?
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correct way to decode AAC?
 
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Hi, What is the correct way to decode aac audio from an mpeg TS? I have a pipeline like this: >gst-launch-1.0 -v filesrc location=multi.ts ! tsparse ! tsdemux program_number=17540 ! aacparse ! faad ! audioconvert ! audioresample ! audio/x-raw, rate=8000, channels=1 ! wavenc ! filesink location=cbbc.wav Setting pipeline to PAUSED ... Pipeline is PREROLLING ... /GstPipeline:pipeline0/MpegTSParse2:mpegtsparse2-0.GstPad:src: caps = video/mpegts, systemstream=(boolean)true, packetsize=(int)188 /GstPipeline:pipeline0/GstTSDemux:tsdemux0.GstPad:sink: caps = video/mpegts, systemstream=(boolean)true, packetsize=(int)188 WARNING: from element /GstPipeline:pipeline0/GstTSDemux:tsdemux0: Delayed linking failed. Additional debug info: ./grammar.y(506): gst_parse_no_more_pads (): /GstPipeline:pipeline0/GstTSDemux:tsdemux0: failed delayed linking some pad of GstTSDemux named tsdemux0 to some pad of GstAacParse named aacparse0 ^Chandling interrupt. Interrupt: Stopping pipeline ... ERROR: pipeline doesn't want to preroll. Setting pipeline to NULL ... Freeing pipeline ... So I tried just saving the raw AAC to a file and converting that as an experiment: >gst-launch-1.0 -v filesrc location=multi.ts ! tsparse ! tsdemux program_number=17540 ! audio/mpeg ! filesink location=cbbc.aac >mediainfo cbbc.aac General Complete name : cbbc.aac Format : LATM File size : 2.38 MiB Overall bit rate mode : Variable Audio Format : AAC Format/Info : Advanced Audio Codec Format profile : LC Bit rate mode : Variable Channel(s) : 2 channels Channel positions : Front: L R Sampling rate : 48.0 kHz Frame rate : 46.875 FPS (1024 spf) Compression mode : Lossy This audio file plays fine in for example VLC However I cannot decode it: >gst-launch-1.0 -v filesrc location=cbbc.aac ! aacparse ! faad ! audioconvert ! audioresample ! audio/x-raw, rate=8000, channels=1 ! wavenc ! filesink location=cbbc.wav Setting pipeline to PAUSED ... Pipeline is PREROLLING ... /GstPipeline:pipeline0/GstAacParse:aacparse0.GstPad:src: caps = audio/mpeg, framed=(boolean)true, mpegversion=(int)4, rate=(int)48000, channels=(int)2, stream-format=(string)loas ERROR: from element /GstPipeline:pipeline0/GstAacParse:aacparse0: Internal data stream error. Additional debug info: gstbaseparse.c(3608): gst_base_parse_loop (): /GstPipeline:pipeline0/GstAacParse:aacparse0: streaming stopped, reason not-negotiated (-4) ERROR: pipeline doesn't want to preroll. Setting pipeline to NULL ... What am I missing here? Regards, Bruce. Kantar Disclaimer _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
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Hi bruce,,
for audio decoding to wav format. Hope this example works for you(i have tested it ) gst-launch-1.0 filesrc location=out.aac ! queue ! aacparse ! faad ! audioconvert ! wavenc ! filesink location=file.wav ----- adi -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/ _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
adi
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RE: correct way to decode AAC?
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Hi,
That’s the same pipeline I'm using except you've added a queue. I tried it anyway in case queue are 'more magical than I think' but perhaps unsurprisingly it doesn't work for me. Could it be something to do with the format. Mediainfo claims the general format is: General Complete name : cbbc.aac Format : LATM File size : 2.38 MiB Overall bit rate mode : Variable Audio Format : AAC Format/Info : Advanced Audio Codec Format profile : LC Bit rate mode : Variable Channel(s) : 2 channels Channel positions : Front: L R Sampling rate : 48.0 kHz Frame rate : 46.875 FPS (1024 spf) Compression mode : Lossy What format did you test? Regards, Bruce. -----Original Message----- From: gstreamer-devel [mailto:[hidden email]] On Behalf Of new baby Sent: 22 May 2018 06:20 To: [hidden email] Subject: Re: correct way to decode AAC? Hi bruce,, for audio decoding to wav format. Hope this example works for you(i have tested it ) gst-launch-1.0 filesrc location=out.aac ! queue ! aacparse ! faad ! audioconvert ! wavenc ! filesink location=file.wav ----- adi -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/ _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
RE: correct way to decode AAC?
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In reply to this post by Adams, Bruce (KMLWG)
It looks like the avdec_aac_latm element was what I was looking for:
>$ gst-inspect-1.0 | grep aac On a related note is it possible to construct a single pipeline that supports both decodings as in: aac -> avdec_aac_latm --> wavenc -> faad -^ Is there an selectable/'or' element? as in the brackets below: gst-launch-1.0 wavenc name=y ! filesink location=file.wav \ filesrc location=out.aac name x. ! aacparse ! (faad | avdec_aac_latm) ! audioconvert ! .y or Something like: gst-launch-1.0 wavenc name=y ! filesink location=file.wav \ filesrc location=out.aac name x. ! aacparse ! avdec_aac_latm ! audioconvert ! .y which doesn't work - doubled to: gst-launch-1.0 wavenc name=y ! filesink location=file.wav \ filesrc location=out.aac name \ x. ! aacparse ! avdec_aac_latm ! audioconvert ! .y x. ! aacparse ! faad ! audioconvert ! .y I do have access to information that identifies the stream type (its in the program mapping table in a DVB MPEG-TS) but I'm curious to know whether a generic pipeline is possible in principle either from the command line or from code. Would it be a desirable patch to create an element combining both somehow (maybe a bin)? Or is it better to be creating the pipeline dynamically once the type has been identified which I think is the only solution without changing gstreamer. Regards, Bruce. -----Original Message----- From: Adams, Bruce (KMLWG) Sent: 22 May 2018 14:16 To: [hidden email] Subject: RE: correct way to decode AAC? Hi, That’s the same pipeline I'm using except you've added a queue. I tried it anyway in case queue are 'more magical than I think' but perhaps unsurprisingly it doesn't work for me. Could it be something to do with the format. Mediainfo claims the general format is: General Complete name : cbbc.aac Format : LATM File size : 2.38 MiB Overall bit rate mode : Variable Audio Format : AAC Format/Info : Advanced Audio Codec Format profile : LC Bit rate mode : Variable Channel(s) : 2 channels Channel positions : Front: L R Sampling rate : 48.0 kHz Frame rate : 46.875 FPS (1024 spf) Compression mode : Lossy What format did you test? Regards, Bruce. -----Original Message----- From: gstreamer-devel [mailto:[hidden email]] On Behalf Of new baby Sent: 22 May 2018 06:20 To: [hidden email] Subject: Re: correct way to decode AAC? Hi bruce,, for audio decoding to wav format. Hope this example works for you(i have tested it ) gst-launch-1.0 filesrc location=out.aac ! queue ! aacparse ! faad ! audioconvert ! wavenc ! filesink location=file.wav _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
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In reply to this post by Adams, Bruce (KMLWG)
Hi bruce,
*I suggest you convert to mp3 and then wav file.* 1) second approche (i have tested it ..) gst-launch-1.0 filesrc location=Transformers1080p.ts ! tsdemux name=demux demux. ! queue ! faad ! lamemp3enc quality=2 target=bitrate bitrate=192 cbr=true ! id3v2mux ! filesink location=file.mp3 gst-launch-1.0 filesrc location=file.mp3 ! queue ! decodebin ! audioconvert ! wavenc ! filesink location=file.wav 2) Format of my .aac file <http://gstreamer-devel.966125.n4.nabble.com/file/t378175/aac.png> ----- adi -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/ _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
adi
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from mediainfo ...the aac format is ADTS..i have extracted aac from .ts from
ffmpeg but do as .mp3 to .wav tested and working . General Complete name : E:\pocVR\VCS\VCS\Race3SalmanKhan720p.aac Format : ADTS Format/Info : Audio Data Transport Stream File size : 3.29 MiB Overall bit rate mode : Variable Audio Format : AAC Format/Info : Advanced Audio Codec Format version : Version 4 Format profile : LC Bit rate mode : Variable Channel(s) : 2 channels Channel positions : Front: L R Sampling rate : 44.1 kHz Frame rate : 43.066 FPS (1024 SPF) Compression mode : Lossy Stream size : 3.29 MiB (100%) ----- adi -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/ _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
adi
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Found the BEST way Directly convert .ts to .wav file like this ...
Hope it solves all your worries *gst-launch-1.0 filesrc location=Transformers1080p.ts ! queue ! decodebin ! audioconvert ! wavenc ! filesink location=file.wav * ----- adi -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/ _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
adi
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RE: correct way to decode AAC?
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What is the purpose of the queue in that pipeline?
-----Original Message----- From: gstreamer-devel [mailto:[hidden email]] On Behalf Of new baby Sent: 23 May 2018 12:54 To: [hidden email] Subject: RE: correct way to decode AAC? Found the BEST way Directly convert .ts to .wav file like this ... Hope it solves all your worries *gst-launch-1.0 filesrc location=Transformers1080p.ts ! queue ! decodebin ! audioconvert ! wavenc ! filesink location=file.wav * ----- adi -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/ _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
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its not mandatory, you can remove it and check .. i guess it will work too
without queue ----- adi -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/ _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
adi
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RE: correct way to decode AAC?
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In reply to this post by Adams, Bruce (KMLWG)
The decodebin element is perhaps a bit of overkill here.
Consider this pipeline: gst-launch-1.0 -v filesrc location=multi.ts ! tsparse ! tsdemux program_number=17540 ! decodebin ! audioconvert ! audioresample ! audio/x-raw, rate=8000, channels=1 ! wavenc ! filesink location=cbbc.wav I get the error: Missing element: H.264 decoder ERROR: from element /GstPipeline:pipeline0/GstDecodeBin:decodebin0: Your GStreamer installation is missing a plug-in. Additional debug info: gstdecodebin2.c(4592): gst_decode_bin_expose (): /GstPipeline:pipeline0/GstDecodeBin:decodebin0: There are patent issues with H264 but yes it would be nice to fix my install. My point though is that I don't care about the video in this pipeline. I really just want an "OR" element Try decoding using A or B E.g. Src = audio/mpeg Sink = audio/x-raw If src=AAC use avdec_aac If src=MPEG use faad Of course the decodebin element gives us that and more but is there a standard way of doing this or a case for something leaner? Regards, Bruce. -----Original Message----- From: gstreamer-devel [mailto:[hidden email]] On Behalf Of Adams, Bruce (KMLWG) Sent: 23 May 2018 12:57 To: Discussion of the development of and with GStreamer Subject: RE: correct way to decode AAC? What is the purpose of the queue in that pipeline? -----Original Message----- From: gstreamer-devel [mailto:[hidden email]] On Behalf Of new baby Sent: 23 May 2018 12:54 To: [hidden email] Subject: RE: correct way to decode AAC? Found the BEST way Directly convert .ts to .wav file like this ... Hope it solves all your worries *gst-launch-1.0 filesrc location=Transformers1080p.ts ! queue ! decodebin ! audioconvert ! wavenc ! filesink location=file.wav * ----- adi -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/ _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
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