Re: [Dvr-devel]dvr wishlist

[Dag B <co...@se...>]

Pierre Hébert wrote:
> 
> Hello Dag B,
> 
> Jingle bells, jingle bells, ... la la la lere

:-)

> > scheduled recording:
> > [year/month/day/hour/minute]
> > [length]
> > [repeat (hourly/daily/weekly/monthly append-name)]
> 
> What do you mean exactly by "append-name" ?

Bad name. But good intentions.
If you record from the same channel at the same time every week, it would be
nice to be able to write to a new file instead of overwriting the old one. So
part of the new filename needs to change every time. Using bits and pieces of
the date/time is probably most useful. Or a counter of some kind. You get the
idea.


> > [filename]
> > [segment size]
> > Optionally use cron to schedule/start recordings.
> > (It *is* the way to do it in unix, after all.)
> 
> Good news, I am actually working at this feature. In fact I am thinking at
> what I should do :
> - a GUI with completely detached "recording core" (a sort of frontend), with
> the ability to edit a sort of cron.
> - a GUI with integrated "recording core", and another command line tool with
> a cron

Your call! But notice that you don't know who owns the Xserver at some point
in the future. So you can't rely on being able to run anything X, unless you
know for a fact that you'll be logged in on the console. But this is
obvious...
Separating the recording core from the GUI may not be so simple with the
current code?

 
> > This of course requires a CLI version of dvr, as we don't know who owns the
> > Xserver at any point in time in the future, or if dvr is actually running.
> >
> > But a CLI (or non-interactive, non-X) version would be nice anyhow...
> > For example linked to motion detection software.
> 
> I am also working at that :-) But it is not as easy as it may seem, due to
> the V4L layer. This is, with avifile, the only obscure part of DVR :-(. It is
> taken from kwintv and I have to rewritte it myself.
> However I love to have CLI tools, as they are almost fully independent of any
> strange things. And work is in progress.

Great!

 
> > ability to encode using mp1e:
> > realtime mpeg1 videoencoding is just plain nice. Besides, it allows for
> > recording of teletext subtitles.
> 
> Hum... I don't know much about mp1e. I would need help and too much time for
> that. But why do you prefer mp1e to Divx, or Indeo ?

1. The subtitle argument above.
2. something (xine or libdivx or avifile or something else) is making divx
being played back way to fast in xine on my system. (Lousy argument, sorry)
3. The ability to record mpeg video would make dvr more "complete".
4. Divx will remain a 'hacker' thing forever. 
5. There is no native Linux Indeo codec.
6. mp1e can chop top and bottom on widescreen movies. (The ones with big
black fields at the top and bottom of your tv.)

> Subtitles can be stored in a ".sub" file and read later by an AVI player I
> think.
> 
> > If dvr uses avifile extensively, it
> > may be difficult to glue in a system() or execve() call?
> 
> Why ?

I am not a coder, so this was a wild guess.
mp1e isn't a library. It is a standalone executable. Other than that, it
appears to accept all normal parameters needed/used in dvr. 
But I have taken the liberty to add a QuickStart guide to mp1e below....

 
> > read channels/parameters from ~/.xawtv, if it exists.
> 
> Perhaps. Xawtv is my prefered TV software, however it is not really important
> for the moment. I put it on my TODO list and we'll see later.

Good. 

 
> > audio capture frequencies corresponding to what is possible
> > of the dsp in question. :-)
> > Current dvr gui only allows for 11025, 22050 and 44100 Hz samplerate.
> > My btaudio dsp-device supports 32k only.
> 
> It is easy to add 32k. I'll do it soon. Check CVS tomorrow.

Thanks!

 
> I would really like to work at all these things. Unfortunately I have to work
> to earn my life, and I don't have much time left. So be patient please...

I will.
Thanks again,


Dag B



mp1e QuickStart guide.

wget http://prdownloads.sourceforge.net/zapping/mp1e-1.9.1.tar.bz2
tar Ixvf mp1e-1.9.1.tar.bz2
cd mp1e-1.9.1
./configure
make
make install
rehash

My ~/.mp1erc looks like this (edit cpu/devices as needed):
----
mux_mode = video_and_audio
cpu = k7
verbose = 1
# motion = 8,24 # requires cpu power...
# filter = 7 # requires v4l2

capture_device = /dev/video
video_bit_rate = 3.5
frame_rate = 25 
image_size = 768x576

pcm_device = /dev/dsp
audio_bit_rate = 32
audio_mode = 2 
sampling_rate = 32
----

Recording like this:
mp1e -n 750 > foo.mpg

for 30 seconds (= 750 frames) of mpeg video.
Or hit Ctrl-C.

List of parameters:

       -a, --audio_mode 0 stereo | 2 dual_channel | 3 mono
       -b, --video_bit_rate float
       -c, --capture_device name
       -f, --frame_rate float
       -g, --gop_sequence string
       -h, --help
       -i, --config filename
       -l, --letterbox
       -m, --mux_mode 1 video | 2 audio | 3 video_and_audio
       -n, --num_frames n
       -p, --pcm_device name
       -r, --rec_source n,m
       -s, --image_size wxh
       -v, --verbose
       -w, --mono
       -x, --mixer_device
              -A, --anno string
       -B, --audio_bit_rate float
       -C, --cpu type
       -F, --filter n
       -G, --grab_size wxh
       -H, --frames_per_seq_header n
       -I, --vbi_device name
       -M, --mute 0 unmute | 1 mute | 2 ignore
       -P, --preview
       -R, --motion min,max
       -S, --sampling_rate float
       -T, --subtitle_pages [nnn,...]
       -V, --version
       -X, --mux 0 nirvana | 1 bypass | 2 mpeg1 | 3 mpeg2-ps | 4