public inbox for linux-media@vger.kernel.org
 help / color / mirror / Atom feed
From: Bob Ingraham <bobi@brin.com>
To: linux-dvb@linuxtv.org, linux-media@vger.kernel.org
Subject: Weird TS Stream from DMX_SET_PES_FILTER
Date: Thu, 19 Mar 2009 16:38:04 -0600 (MDT)	[thread overview]
Message-ID: <1002969792.105131237502284915.JavaMail.root@email> (raw)
In-Reply-To: <1519873602.105111237502250958.JavaMail.root@email>

Hello,

I've been using the Linux DVB API to grab DBV-S MPEG2 video packets using a TechniSat S2 card.

But something seems odd about DMX_SET_PES_FILTER.

It returns a TS packets for my pid just fine, but by MPEG2 frames have no PES headers!  The raw compressed MPEG2 frames just immediately follow the TS/adapation-field headers directly.

When I wrote my TS packet decoder, I was expecting to have to decode PES headers after the TS header. But instead I found the raw compressed frames.

They decode fine (with ffmpeg's libavcodec mpeg2 decoder,) and they look fine when rendered using SDL.

But besides my own program, I can't get vlc or mplayer to decode this stream. Both vlc and mplayer sense a TS stream, but then they never render anything because, I suspect, that they can't find PES headers.

So, two questions:

1. Am I crazy or is DMX_SET_PES_FILTER returning a non-standard TS stream?

2. Is there a way to receive a compliant MPEG-TS (or MPEG2-PS,) stream?

3. Should I use DMX_SET_FILTER instead?

4. If so, what goes in the filter/mask members of the dmx_filter_t struct?


Thanks,
Bob

PS: I use the following to filter on my video stream pid (0x1344):

 struct dmx_pes_filter_params f;

 memset(&f, 0, sizeof(f));
 f.pid = (uint16_t) pid;
 f.input = DMX_IN_FRONTEND;
 f.output = DMX_OUT_TS_TAP;
 f.pes_type = DMX_PES_OTHER;
 f.flags   = DMX_IMMEDIATE_START;


       reply	other threads:[~2009-03-19 22:40 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1519873602.105111237502250958.JavaMail.root@email>
2009-03-19 22:38 ` Bob Ingraham [this message]
2009-03-20  9:09   ` [linux-dvb] Weird TS Stream from DMX_SET_PES_FILTER Brice Dubost

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1002969792.105131237502284915.JavaMail.root@email \
    --to=bobi@brin.com \
    --cc=linux-dvb@linuxtv.org \
    --cc=linux-media@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox