Encoding and decoding of RAW RTSP video frames

Raghu Msrp raghu.msrp at gmail.com
Thu May 23 16:34:22 UTC 2019


Dear List,

I was interested to know if gstreamer rtsp can handle transmission of pure
RAW video frames to a client. To be more specific, my question here is, if
I transfer pure raw video frames with no encoding to a client using rtsp
protocol, do I still need to do decoding of frames? If yes, can someone in
the list explain the reason?

Secondly, in gstreamer, if I use raw encoding on video frames, what kind of
encoding is performed on the frames? Does it compress the frames to a
larger extent?

My understanding is if I encode the frame using h264 or vp8 or mpeg then
only I have to decode. Please correct my understanding if I am wrong.

On the raw frames, can I use rtsp gstreamer protocol to visualize without
decoding it. Is decoding mandatory?

Request the list to kindly clarify the above queries.


On Wed, May 22, 2019, 19:45 <gstreamer-devel-request at lists.freedesktop.org>
wrote:

> Send gstreamer-devel mailing list submissions to
>         gstreamer-devel at lists.freedesktop.org
>
> To subscribe or unsubscribe via the World Wide Web, visit
>         https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
> or, via email, send a message with subject or body 'help' to
>         gstreamer-devel-request at lists.freedesktop.org
>
> You can reach the person managing the list at
>         gstreamer-devel-owner at lists.freedesktop.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of gstreamer-devel digest..."
>
>
> Today's Topics:
>
>    1. Re: Sound volume is very low when playing mkv file (longkas)
>    2. Change RTSP Server source IP address (David Jaggard)
>    3. AW: Change RTSP Server source IP address (Thornton, Keith)
>    4. Re: Change RTSP Server source IP address (David Jaggard)
>    5. Re: Sound volume is very low when playing mkv file (longkas)
>    6. Re: Sound volume is very low when playing mkv file (Tim Müller)
>    7. Re: MPEG-TS the ongoing story (Russel Winder)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Wed, 22 May 2019 07:23:34 -0500 (CDT)
> From: longkas <longkas at gmail.com>
> To: gstreamer-devel at lists.freedesktop.org
> Subject: Re: Sound volume is very low when playing mkv file
> Message-ID: <1558527814965-0.post at n4.nabble.com>
> Content-Type: text/plain; charset=us-ascii
>
> I'm not sure if it is because the audio stream in the mkv has 6 channels,
> I'm
> using decodebin to translate streams, maybe I could combine it into 2
> channel audio streams, I need some help
>
>
> BR
>
>
>
> --
> Sent from: http://gstreamer-devel.966125.n4.nabble.com/
>
>
> ------------------------------
>
> Message: 2
> Date: Wed, 22 May 2019 14:08:52 +0100
> From: David Jaggard <davywj at gmail.com>
> To: Discussion of the development of and with GStreamer
>         <gstreamer-devel at lists.freedesktop.org>
> Subject: Change RTSP Server source IP address
> Message-ID:
>         <
> CAJAmR4ZOSjBpSeOKRc0fZ6A71uwgVXU4C9W1c2qFPtGhT-6_Rg at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
>
> Hello
>
> Using the example in the test-readme.c file of the RTSP server, how can I
> change the source IP address of the RTP packets to specific address on a
> multi-homed PC?
>
> At present it is choosing the first address.
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: <
> https://lists.freedesktop.org/archives/gstreamer-devel/attachments/20190522/b90779fe/attachment-0001.html
> >
>
> ------------------------------
>
> Message: 3
> Date: Wed, 22 May 2019 13:23:35 +0000
> From: "Thornton, Keith" <keith.thornton at zeiss.com>
> To: Discussion of the development of and with GStreamer
>         <gstreamer-devel at lists.freedesktop.org>
> Subject: AW: Change RTSP Server source IP address
> Message-ID: <7153D1686E3590498D57D986E0F83BA60ADCB889 at adeerl01sms004>
> Content-Type: text/plain; charset="utf-8"
>
> Hi,
> After calling gst_rtsp_server_new you can set the address with
> gst_rtsp_server_set_address otherwise it will use 127.0.0.1
>
> Von: gstreamer-devel <gstreamer-devel-bounces at lists.freedesktop.org> Im
> Auftrag von David Jaggard
> Gesendet: Mittwoch, 22. Mai 2019 15:09
> An: Discussion of the development of and with GStreamer <
> gstreamer-devel at lists.freedesktop.org>
> Betreff: Change RTSP Server source IP address
>
> Hello
>
> Using the example in the test-readme.c file of the RTSP server, how can I
> change the source IP address of the RTP packets to specific address on a
> multi-homed PC?
>
> At present it is choosing the first address.
>
>
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: <
> https://lists.freedesktop.org/archives/gstreamer-devel/attachments/20190522/7a369e10/attachment-0001.html
> >
>
> ------------------------------
>
> Message: 4
> Date: Wed, 22 May 2019 14:27:49 +0100
> From: David Jaggard <davywj at gmail.com>
> To: Discussion of the development of and with GStreamer
>         <gstreamer-devel at lists.freedesktop.org>
> Subject: Re: Change RTSP Server source IP address
> Message-ID:
>         <
> CAJAmR4aph0A0O2Q2ooFqX9+a7iUq7-qUTovKmJmWwm1kipiwug at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
>
> Hi Keith,
>
> Thanks for your reply. That sets the listen address of the RTSP server but
> doesn't change the src address of the RTP packets.
>
> On Wed, 22 May 2019 at 14:23, Thornton, Keith <keith.thornton at zeiss.com>
> wrote:
>
> > Hi,
> >
> > After calling gst_rtsp_server_new you can set the address with
> > gst_rtsp_server_set_address otherwise it will use 127.0.0.1
> >
> >
> >
> > *Von:* gstreamer-devel <gstreamer-devel-bounces at lists.freedesktop.org>
> *Im
> > Auftrag von *David Jaggard
> > *Gesendet:* Mittwoch, 22. Mai 2019 15:09
> > *An:* Discussion of the development of and with GStreamer <
> > gstreamer-devel at lists.freedesktop.org>
> > *Betreff:* Change RTSP Server source IP address
> >
> >
> >
> > Hello
> >
> >
> >
> > Using the example in the test-readme.c file of the RTSP server, how can I
> > change the source IP address of the RTP packets to specific address on a
> > multi-homed PC?
> >
> >
> >
> > At present it is choosing the first address.
> >
> >
> >
> >
> > _______________________________________________
> > gstreamer-devel mailing list
> > gstreamer-devel at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: <
> https://lists.freedesktop.org/archives/gstreamer-devel/attachments/20190522/7b8630e1/attachment-0001.html
> >
>
> ------------------------------
>
> Message: 5
> Date: Wed, 22 May 2019 08:50:28 -0500 (CDT)
> From: longkas <longkas at gmail.com>
> To: gstreamer-devel at lists.freedesktop.org
> Subject: Re: Sound volume is very low when playing mkv file
> Message-ID: <1558533028272-0.post at n4.nabble.com>
> Content-Type: text/plain; charset=us-ascii
>
> Ok, my research is to use volume element to raise the volume, and use
> audioconvert to downmix the 5.1 DTS audio to stereo, I dont know how to
> find
> the current volume though:
>
> gst-launch-1.0 -v filesrc location=g:/gtg.mkv ! decodebin !
> audio/x-raw,channels=6 \
>      ! audioconvert mix-matrix="<<(float)1.0, (float)0.0, (float)1.0,
> (float)1.0, (float)1.0, (float)0.0>, <(float)0.0, (float)1.0, (float)1.0,
> (float)1.0, (float)0.0,(float)1.0>>" !   audio/x-raw,channels=2  \
>     ! volume volume=10.0  ! autoaudiosink
>
>
>
>
>
> --
> Sent from: http://gstreamer-devel.966125.n4.nabble.com/
>
>
> ------------------------------
>
> Message: 6
> Date: Wed, 22 May 2019 15:00:29 +0100
> From: Tim Müller <tim at centricular.com>
> To: Discussion of the development of and with GStreamer
>         <gstreamer-devel at lists.freedesktop.org>
> Subject: Re: Sound volume is very low when playing mkv file
> Message-ID:
>         <748661b0e32dc2178225fa7a9ff0f4ca5a518717.camel at centricular.com>
> Content-Type: text/plain; charset="UTF-8"
>
> On Wed, 2019-05-22 at 07:23 -0500, longkas wrote:
>
> > I'm not sure if it is because the audio stream in the mkv has 6
> > channels, I'm using decodebin to translate streams, maybe I could
> > combine it into 2channel audio streams, I need some help
>
> What codec/format is the audio stream (gst-discoverer-1.0 -v file.mkv)?
>
> And what decoder is being used in your case? (see output of gst-play-
> 1.0 -v or gst-launch-1.0 -v)
>
> Is the decoder outputting 2 channels or 6 channels?
>
> It might be that this is caused by e.g. AC-3 audio being downmixed to 2
> channels improperly.
>
> Cheers
>  -Tim
> --
> Tim Müller, Centricular Ltd - http://www.centricular.com
>
>
>
> ------------------------------
>
> Message: 7
> Date: Wed, 22 May 2019 15:15:06 +0100
> From: Russel Winder <russel at winder.org.uk>
> To: Discussion of the development of and with GStreamer
>         <gstreamer-devel at lists.freedesktop.org>
> Subject: Re: MPEG-TS the ongoing story
> Message-ID:
>         <702b56ef5099a0db13a551d981ebe810d1dab8fb.camel at winder.org.uk>
> Content-Type: text/plain; charset="utf-8"
>
> On Wed, 2019-05-22 at 13:20 +0300, Sebastian Dröge wrote:
> > On Wed, 2019-05-22 at 10:32 +0100, Russel Winder wrote:
> > > I am wondering if I am missing something other than "it's never been
> > > needed before".
> >
> > That seems to be the case, yes. Please send a patch if you need it :)
>
> I am guessing then that I need to do the C thing for entry into the MPEG-TS
> library itself rather than just fill the gap in Rust in the MPEG-TS
> wrapper.
> And I promised myself never to do any C programming again. Oh well.
>
> Would changes get into GStreamer 1.16.1 or would it have to wait for
> 1.18.0?
>
> --
> Russel.
> ===========================================
> Dr Russel Winder      t: +44 20 7585 2200
> 41 Buckmaster Road    m: +44 7770 465 077
> London SW11 1EN, UK   w: www.russel.org.uk
>
> -------------- next part --------------
> A non-text attachment was scrubbed...
> Name: signature.asc
> Type: application/pgp-signature
> Size: 833 bytes
> Desc: This is a digitally signed message part
> URL: <
> https://lists.freedesktop.org/archives/gstreamer-devel/attachments/20190522/fc31217d/attachment.sig
> >
>
> ------------------------------
>
> Subject: Digest Footer
>
> _______________________________________________
> gstreamer-devel mailing list
> gstreamer-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
>
> ------------------------------
>
> End of gstreamer-devel Digest, Vol 100, Issue 73
> ************************************************
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/gstreamer-devel/attachments/20190523/9add9b17/attachment-0001.html>


More information about the gstreamer-devel mailing list