Motion, saved files lower quality than live stream.

8JhN · 02-16-2018, 01:53 PM

Is it possible to save video without compression?

ffplay gives this information from stream:

Stream #0:0: Video: h264 (High), yuv420p, 1920x1080, 25 fps, 15 tbr, 90k tbn, 50 tbc

I've already set ffmpeg_variable_bitrate to 100, framerate to 25, width 1920 and height 1080. Saved files are not so good than live stream

I'm using FreeBSD, but I think that's irrelevant..

teckk · 02-16-2018, 04:50 PM

h264 is already really good compression.
How are you saving the stream? Are you reencoding it?
If you don't want the q changed then don't reencode it.

Quote:

Is it possible to save video without compression?

Yes, it will be huge.

You can always dump the stream unchanged to file

Code:

mplayer <url> -dumpsteam -dumpfile outfile.ts

Code:

ffmpeg -i <url> -c:a copy -c:v copy output.ts

Why don't you post what you are trying to do.

8JhN · 02-16-2018, 05:01 PM

I'm using Motion security camera software. Stream coming from IP-camera is already compressed.

This is from my config file:

# Codec to used by ffmpeg for the video compression.
# Timelapse mpegs are always made in mpeg1 format independent from this option.
# Supported formats are: mpeg1 (ffmpeg-0.4.8 only), mpeg4 (default), and msmpeg4.
# mpeg1 - gives you files with extension .mpg
# mpeg4 or msmpeg4 - gives you files with extension .avi
# msmpeg4 is recommended for use with Windows Media Player because
# it requires no installation of codec on the Windows client.
# swf - gives you a flash film with extension .swf
# flv - gives you a flash video with extension .flv
# ffv1 - FF video codec 1 for Lossless Encoding ( experimental )
# mov - QuickTime ( testing )
ffmpeg_video_codec mpeg4

I only need Motion save stream to hard disk. Here's default config.

teckk · 02-16-2018, 05:19 PM

How are you dumping the stream to file now? Are you reencoding it?
Are you playing the stream with ffplay? Then ffmpeg will dump it. or mplayer, mpv, vlc etc.

8JhN · 02-16-2018, 05:27 PM

I use ffplay only to watch stream. Motion saves streams itself using config file.

teckk · 02-17-2018, 08:12 AM

Quote:

I use ffplay only to watch stream.

Ok, is there something in posts 2 and 4 that doesn't work for you?

Edit:
When you say that you are watching the stream with ffplay, do you mean the stream from the camera, or the file after it has been downloaded to your HD? Stream means what is coming from the camera.

If you mean a file after it has already been made, and you don't like the quality, then you'll need to configure Motion to stop encoding in poor q and make a better q.

Or grab the stream coming from the camera, with v4l, or ffmpeg, and dump to file raw, then reencode to the format that you want.
Or encode to a good format on the fly.

Quote:

Stream coming from IP-camera is already compressed.

Does that mean that it is already encoded in to a format like x264?
Then you'll need to start there.
Looked at this
http://www.linux-projects.org/downlo...es/motion.conf
Looks like it uses v4l2 and ffmpeg.
You should be able access the cam, with v4l2 then, and encode the stream however you want.
Example:

Code:

ffmpeg -f v4l2 -s 320x240 -i /dev/video0 -c:v libx264 -b:v 300k out.avi
ffplay -f v4l2 -s 320x240 -i /dev/video0

Edit2:
Look at the man pages and docs for ffmpeg and v4l2
A better q will probably be

Code:

ffmpeg -f v4l2 -s 320x240 -i /dev/video0 -crf 18 -preset slow -s 640x480 output.mp4

Not sure if you can do that on the fly though. Depends on how good a processor that you have. You may want to dump raw then reencode later.

Edit3:
Sorry, I keep finding things in my noted that will help you out.

Code:

v4l2-ctl --list-formats-ext
v4l2-ctl --list-device
ffmpeg -f video4linux2 -list_formats all -i /dev/video0

ondoho · 02-17-2018, 03:00 PM

Quote:

Originally Posted by 8JhN

I've already set ffmpeg_variable_bitrate to 100

that is very little.
it is a little difficult to give proper advice since you cannot (?) show us any commands, or where you actually entered that setting.