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ravs
6th May 2017, 11:43
I have a digital satellite receivers and use these to record TV stuff on external hard disk. And the few stuff I want to keep, I plan to encode using ffmpeg.

Some TV stations (like arte) broadcast in quite a good quality, but lots of "private channels" (commercial stations) often broadcast in less good quality.

I put together two sets for encoding with ffmpeg, they both have okay to inferior quality when encoding a good quality broadcast, and always inferior quality when encoding less good quality source.

Here are my sets so far:

time ffmpeg -v error -y -i INFILE -crf 35.0 -vcodec libx264 -preset slow -acodec libvo_aacenc -ar 48000 -ab 128k -coder 1 -flags +loop -vf yadif OUTFILE

and

ffmpeg -v error -y -flags +ilme+ildct -i INFILE -crf 35.0 -vcodec libx264 -preset slow -acodec libvo_aacenc -ar 48000 -ab 128k -coder 1 -flags +loop -mbd rd -trellis 2 -cmp 2 -subcmp 2 -g 100 OUTFILE


I hope I did choose the right sub-forum for my question, if not, please move the post.

sneaker_ger
6th May 2017, 11:54
I don't see any question.

stax76
6th May 2017, 12:11
In my experience ffmpeg creates async output for many TS files. How to you cut/trim the recordings?

ravs
6th May 2017, 12:37
In my experience ffmpeg creates async output for many TS files. How to you cut/trim the recordings?

I either use ffmpeg, or when there is more to cut, I use avidemux.

With avidemux: Saving as avi container for now, using copy/copy for both video and audio, since the mpeg-2 container results in a video without sound, have not figured out why that is...


I don't see any question.

The question is: both parameter-sets I use for ffmpeg have inferior quality, especially when the broadcast itself was not that good a quality, and I ask for ffmpeg parameters that would give me better encoding results.

lvqcl
6th May 2017, 14:02
BTW, libvo_aacenc is one of the worst audio encoders. Also it has been removed from FFMPEG more than a year ago.

raffriff42
7th May 2017, 01:27
okay to inferior quality when encoding a good quality broadcast, and always inferior quality when encoding less good quality source
...
-crf 35.0Please try -crf 22.0 more or less. Crf 35 is about the worst quality imaginable.

ravs
8th May 2017, 11:25
In my experience ffmpeg creates async output for many TS files. How to you cut/trim the recordings?

Usually I use avidemux, then ffmpeg for encoding. All presets I used from avidemux itself have been slow, and the quality, well... not satisfactory.

BTW, libvo_aacenc is one of the worst audio encoders. Also it has been removed from FFMPEG more than a year ago.

That explains a lot... I think my version of ffmpeg is outdated.
(Since my GLIBC of my Slackware based Linux is not the most recent, I cannot install the most recent versions of any software, and it has to be x86-64 as well)

Please try -crf 22.0 more or less. Crf 35 is about the worst quality imaginable.

Thanks, I read the readme / the ffmpeg info text file (the large one), but seems I still missed a lot. :o

ravs
19th May 2017, 14:58
Sorry for the late reply.

I did reply two times, but for some reasons these have not been posted. (It said an admin or moderator has to check my post)

So, here I try again:

How to you cut/trim the recordings?

avidemux. But I have issues with some commercials or initial broadcast I want to cut out.
At times I have to delete images cause the previous sound is laid over the images of the movie I want to keep. (It's because of the delay between image and sound, I presume)
Is there a way to fix that? Do I have to mute the sound each time there is such a cut?

Please try -crf 22.0 more or less. Crf 35 is about the worst quality imaginable.

Thanks, I use -crf 22.0 now and it's much better. :)